Three sesquiterpenoids and nine iridoids were isolated from the roots and rhizomes of Valeriana jatamansi by various chromatographic methods. Their structures were identified by physicochemical properties, NMR and MS data. Among them, valeriananoid G (1) was a new patchoulol-type sesquiterpenoid, and compound 3 was isolated from the genus Valeriana for the first time. Compounds 3 and 10 exhibited significant inhibitory effects on nitric oxide production induced by lipopolysaccharide in RAW 264.7 macrophages, with IC₅₀ values of 19.00 and 3.66 μmol·L^-1, respectively. In addition, compounds 4, 6 and 12 showed anti-influenza virus activity with IC₅₀ values of 51.75, 51.40 and 102.08 μmol·L^-1, respectively.

Numerous in vitro studies have shown that most pyrrolizidine alkaloids (PAs) are hepatotoxic after being metabolically activated by cytochrome P450 (CYP) 3A4. However, the key role of CYP3A4 has not been confirmed in vivo. Therefore, the CYP3A4 chemical inhibitor ritonavir was employed in this work and the effect of ritonavir on Gynura japonica-induced liver injury in rats was investigated. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine. Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. Acute liver injury was induced by a single gavage of Gynura japonica extracts (GJE, 8 g·kg^-1); rats in the protection group were gavaged with ritonavir (RIT, 30 mg·kg^-1) 1 h before GJE treatment. The results show that RIT could significantly attenuate GJE-induced liver injury in rats. Rats in the protection group showed decreased serum activities for alanine aminotransferase and aspartate aminotransferase, as well as lower total bile acids. In addition, the infiltration of inflammatory cells, sinusoidal hemorrhage, and hepatic necrosis in GJE-treated rats were markedly attenuated in the protection group. The content of pyrrole-protein adducts (PPAs), a recommended biomarker for PA-induced hepatotoxicity in clinics, was determined at 10 min to 24 h after GJE treatment. The content of 13 bile acids was also quantified. RIT treatment reduced the content of PPAs in serum dramatically and restored the impaired bile acid homeostasis caused by GJE. These studies indicate that RIT attenuated Gynura japonica-induced liver injury in rats, which was closely related to the inhibition of the metabolic activation of PAs and the regulation of bile acid metabolism. These results provide a better understanding of the relationship between CYP3A4 and PA-induced toxicity. This work will also be helpful in developing effective treatments for PA-induced liver injury and making a reasonable evaluation of the safety of drugs containing PAs in clinic.

To simultaneously determine the contents of p-coumaric acid, chlorogenic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, caffeic acid and ferulic acid in Imperatae Rhizoma concentrated granules, an ultra-high performance liquid chromatography (UPLC) with two internal references method (TIRM) was established and validated. Chromatographic separation was achieved on a ZORBAX RRHD Eclipse Plus C18 column (2.1 mm×100 mm, 1.8 μm) using 1.7 mmol·L^-1 oxalic acid in water and methanol as mobile phase. The flow rate was 0.4 mL·min^-1 and the column temperature was set as 35℃. The relative correction factors (RCFs) of caffeic acid and ferulic acid using p-coumaric acid as internal reference were calculated and the RCFs of 4-caffeoylquinic acid and 5-caffeoylquinic acid were calculated using chlorogenic acid as the internal reference. The TIRM was fully validated for linearity, accuracy, repeatability, stability and recovery so that it could be compared with the external standard method (ESM). The RCFs of 5-caffeoylquinic acid, 4-caffeoylquinic acid, caffeic acid, and ferulic acid were 1.069, 1.022, 1.368, and 1.493, respectively. The TIRM and ESM were used to determine the contents of six ingredients in Imperatae Rhizoma concentrated granules from different manufacturers and the variation between results was within acceptable limits. In conclusion, the newly established TIRM allowed simultaneous determination of six ingredients (p-coumaric acid, chlorogenic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, caffeic acid, ferulic acid) in Imperatae Rhizoma concentrated granules, providing support for the quality control of this traditional Chinese medicine.

Vaccination is an effective way to reduce the morbidity and mortality of infectious diseases. As a needle-free transcutaneous immunization (NF-TCI) vaccination technology, microneedles (MNs), composed of multiple micro-needles orderly attached to a substrate, can overcome the problems of low immune efficiency, poor compliance and waste of resources that exists in the conventional vaccination by injection, thus becoming a research hotspot in biomedicine. The microneedle vaccine can directly break through the stratum corneum barrier of the skin without touching nerves and blood vessels in the dermis, and effectively delivers the vaccine to the immune cells in the skin tissue to initiate the immune response of the body, thus triggering strong humoral and cellular immune processes. Vaccine delivery via the MNs system possesses the advantages of high safety, satisfying immune effect and practical economy, and shows great prospect in the prevention and treatment of infectious diseases and antineoplastic therapy. This article reviews the development background of MNs in transcutaneous immunization, the types of vaccine delivery, the factors affecting the immune effect, the problems to be solved and development direction in the future.

The development of nanotechnology has made it possible to develop safe, efficient, precise and controllable drug delivery system (DDS). Among them, organic or inorganic synthetic nanocarriers have been widely reported and used for the delivery of tumor therapeutic agents. However, some of carriers have several problems, such as easily eliminated by the body's immune system, difficult to preparation or poor safety in vivo. In recent years, with the development of biomedicine, biomimetic technology based biomembrane-mediated nanodrug delivery has organically integrated the low immunogenicity of natural biomembrane, cancer targeting, and the controllable and multifunctional of smart nanocarrier design. It will achieve a new breakthrough of nanotechnology in cancer targeted therapy. Based on the recent advances of cell membrane-derived biomimetic nanotechnology and the nanomedicine in the field of cancer therapy, this review discusses the three aspects including the experimental basis of cell membrane-derived biomimetic nanotechnology, the classification of biomimetic nanodrug delivery platforms, and the application in cancer targeted therapy. Therefore, the review will provide reference for the design of smart drug delivery system and its development in cancer targeted treatment.

Chemoimmunotherapy has attracted much attention as an emerging therapy pattern for the treatment of cancers. Exploring effective drug combination schemes and reasonable delivery methods remained the key issue in current research. Herein, we designed sorafenib (SF) and anti-Tim-3 monoclonal antibody (Tim-3 mAb) co-loaded MMP2-responsive mesoporous silica nanoparticles (ST-MSNs) for combined chemoimmunotherapy of hepatocellular carcinoma (HCC). The shell of ST-MSNs was fabricated by Tim-3 mAb through matrix metalloproteinase 2 (MMP2) sensitive peptides as "gatekeepers" to prevent drug release during the blood circulation. In tumor microenvironment, the high levels of MMP2 caused the responsive shedding of Tim-3 mAb, leading to the triggerred release of SF and Tim-3 mAb. Then, SF could be delivered to tumor cells and Tim-3 mAb could be delivered to T cells, respectively. In vivo tumor inhibition study results demonstrated that ST-MSNs can significantly enhance synergistic antitumor activity compared with sequential administration of free SF solution and Tim-3 mAb solution. Meanwhile, the expression of antitumor cytokines IFN-γ, IL-12 and the percentage of CD3⁺CD4⁺ cells, CD3⁺CD8⁺ cells in tumors were upregulated after the administration of ST-MSNs, demonstrating good immunomodulatory ability. In addition, within the dosage range, the ST-MSNs had low cytotoxicity and hemolysis, and no obvious tissue toxicity was observed. All animal experiments were performed in line with national regulations and approved by the Animal Experiments Ethical Committee of Shandong University. In conclusion, this study provided a promising drug combination of chemoimmunotherapy with good application prospects for clinical HCC treatment, and exhibited a potential drug carrier for clinical chemoimmunotherapy.

In recent years, immunotherapy has made great progress in clinical cancer therapy. However, the poor tumor specificity, low intra-tumoral penetration, and low cellular uptake in the systemic delivery of immunotherapeutic drugs lead to low efficacy and poor safety, limiting the development of immunotherapy. Active tumor-targeting nano drug delivery systems (aNDDS) can enhance the concentration of drugs in target cells through the interaction between surface-conjugated antibodies or ligands and the receptors on target cell membranes, providing a viable strategy for specific and efficient drug delivery. In addition, some specific types of cell membranes with the natural targeting ability have been exploited for the construction of biomimetic nanocarriers to improve the drug delivery efficiency. In view of the many advantages of active tumor-targeting nanocarriers, researchers also have designed a series of aNDDS for promoting antitumor immune responses and proved that they improved the efficacy and safety of immunotherapy. In this review, we summarize the recent progress on aNDDS for improving the tumor immunotherapy and look forward to the main challenges and future directions in this field.

Polydopamine (PDA) is a novel type of polymer synthesized inspired by adhesion proteins in mussels. It has been widely used in tumor-targeting drug delivery systems due to its natural advantages such as good biocompatibility, excellent photothermal conversion performance, adhesion, high chemical reactivity and multiple drug release response mechanisms. This review summarizes the applications of PDA-based tumor-targeting drug delivery in recent years, hoping to provide references for designing a more reasonable and effective PDA-based multifunctional collaborative tumor therapy platform.

Nanotechnology has shown broad application prospects in the diagnosis and treatment of cancer. Currently, nearly 80 cancer nanomedicines are under clinical investigation, and many have been approved with enhanced anti-tumor efficacy and decreased side effects. However, the presence of various barriers in related basic research, process control and clinical trials lead to extremely low translation rate. From the perspective of clinical commercialization, we summarized the progress, clinical status, challenges and opportunities of cancer nanomedicine, and presented a cutting-edge prospect on the rational design of nanomedicine and clinical trial strategies.

As a basic amino acid, histidine has a pK_a close to the acidity of the tumor microenvironment, thus the charge and solubility of histidine are able to vary as the pH changes. Under a neutral environment, histidine is not charged and exhibits hydrophobic properties, while it can be protonated and becomes hydrophilic when exposed to mildly acidic pH, such as tumor microenvironment. Therefore, histidine is widely used in the design of drug delivery systems to target the mildly acidic pH of tumor microenvironment. This article reviews the recent progresses of histidine-based tumor-targeting drug delivery systems, and summarizes the principles on promoting internalization and tuning drug release by taking advantage of histidine. Finally, we point out the common issues on histidine application and illustrate its future prospects.