Antiviral drug research and development is an important research direction in the current and future biomedical field. The research and development of antiviral drugs not only requires the application of new strategies and new technologies, but also requires the complementary advantages and close cooperation of project teams. Based on the latest progress in this field and the author's drug research practice, this paper summarizes the underlying logic, innovative thinking and research paradigm of antiviral medicinal chemistry.

At present, brain disease has become a "killer" in the field of general health, and the existence of blood-brain barrier has become one of the challenges in drug delivery into the brain. According to studies, cell membrane coating technique can endow nanoparticles with the characteristics of immune escape, long circulation, targeted delivery, and so on. Therefore, membrane biomimetic nanoparticles have been widely used in the field of disease treatment. Among them, the cell membrane derived from immune cells, tumor cells, and stem cells can cross the blood-brain barrier through the transcellular pathway and cell bypass pathway, which is used to prepare biomimetic membrane nanoparticles to break through the blood-brain barrier to achieve the treatment of brain diseases. What's more, the brain targeted ability of biomimetic nanoparticles would be further enhanced by modifying the cell membrane with peptides. This paper introduces the preparation methods of membrane biomimetic nanoparticles, expounds in detail the way that cell membrane coated nanoparticles break through the blood-brain barrier and achieve efficient intracerebral drug delivery. It also summarizes the prospects and challenges of this novel drug delivery system in the treatment of brain diseases, providing a reference for the research of membrane biomimetic nanoparticles in the treatment of brain diseases.

After entering the body from the drug delivery site, antitumor nanomedicines need to cross a series of physiopathological barriers to reach the target site of action to effectively exert antitumor therapeutic effects. The ligand modification strategy is a classic method to enhance the efficiency of nanomedicine delivery in vivo, but the contradiction between the single ligand modification strategy, which is characterized by unity and stage, and the in vivo delivery process, which is characterized by versatility and whole-process characteristics, determines that nanomedicines modified by a single ligand alone cannot satisfy the target efficacy requirements. Therefore, the use of multiligand combinatorial modification strategies by virtue of nanomedicine surface area advantages is key to advancing the next generation of smart nanomedicines. In this paper, on the basis of summarizing and classifying the commonly used functional ligands for in vivo delivery, the advantages and research progress of multiligand combination modification of antitumor nanomedicines are discussed with special focus, and the multiligand combination modification is classified as synergistic and complementary according to the combination of the ligands, which is of great significance to ensure that antitumor nanomedicines can overcome the multiple physiopathological barriers to achieve precise delivery.

Rare diseases still lack effective treatments, and the development of drugs for rare diseases (known as orphan drugs) is an urgent medical problem. As natural active ingredients in living organisms, some biomacromolecule drugs have good biocompatibility, low immunogenicity, and high targeting. They have become one of the most promising fields in drug research and development in the 21st century. However, there are still many obstacles in terms of in vivo delivery. In view of the unique advantages of nanocarriers prepared from polymers, lipids, organic biomimetic and inorganic materials in drug delivery, researchers are committed to building an efficient delivery system with versatility and synergy to solve the bottleneck issues in treating rare diseases with biomacromolecule drugs. Therefore, this article reviews the research progress of nanocarrier delivering proteins, peptides and nucleic acids in the field of rare disease treatment in the past ten years, which provides ideas for researches on biomacromolecule drug nanosystems in the field of treatment of rare diseases.

Amorphous solid dispersion (ASD) is one of the most effective formulation approaches to enhance the water solubility and oral bioavailability of poorly water-soluble drugs. However, maintenance of physical stability of amorphous drug is one of the main challenges in the development of ASD. Crystallization is a process of nucleation and crystal growth. The nucleation is the key factor that influences the physical stability of the ASD. However, a theoretical framework to describe the way to inhibit the nucleation of amorphous drug is not yet available. We reviewed the methods and theories of nucleation for amorphous drug. Meanwhile, we also summarized the research progress on the mechanism of additives influence on nucleation and environmental factors on nucleation. This review aims to enhance the better understanding mechanism of nucleation of amorphous drug and controlling over the crystal nucleation during the ASD formulation development.

Biomacromolecule drugs have been increasingly used in clinical practice due to their distinct advantages, including precise targeting, small dose, high safety and activity. However, owing to their high molecular weight, strong hydrophilicity, and poor stability in the gastrointestinal tract, the oral bioavailability of the biomacromolecule drugs remains extremely poor. As a novel and innovative technology for active drug delivery, gastrointestinal microneedles hold immense potential in the oral delivery of biomacromolecule drugs because of their low-invasive nature and high permeation enhancement effects. This review primarily summarizes the actuating force, design strategies, fabrication techniques, and applications of gastrointestinal microneedles for the oral delivery of biomacromolecule drugs. Additionally, the challenges and further perspectives in the development this technology are presented, aiming to promote the subsequent research and clinical translation of gastrointestinal microneedles, and to provide a new efficient and safe strategy for oral delivery of biomacromolecule drugs.

Misuse of pyrrolizidine alkaloid (PA)-containing herbs is the major cause of hepatic sinusoidal obstruction syndrome (HSOS) in China. And diuretics are among the most commonly used medications for the treatment of PA-induced HSOS in clinical practice. As a traditional diuretic in traditional Chinese medicine, the diuretic mechanism of Alismatis Rhizoma (AR) has not been fully clarified, and there is no report on AR ameliorating PA-induced HSOS from a diuretic point of view. Therefore, this study aims to investigate the therapeutic potential of alisol B 23-acetate (AB23A) against acute liver injury induced by senecionine (a representative toxic PA) in mice, and to further elucidate its effect on impaired water-liquid balance in mice exposed to PA. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine (Registration number: PZSHUTCM220808017). Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. Model of mice was induced by a single oral exposure of senecioine (50 mg·kg^-1) (SEN group), and AB23A (40 mg·kg^-1) intervention group (AB23A+SEN group), solvent control group (Ctrl group) and AB23A control group (AB23A group) were set up. The results showed that AB23A could significantly attenuate the levels of serum biochemical indices of liver functions in senecioine-induced acute liver injury mice, as evident by alleviated hepatocyte necrosis and hepatic sinusoidal stasis. AB23A also improved kidney function of mice exposed to senecionine, fascinated urinary excretion and repaired electrolyte disorders, as well as decreased content of senecioine metabolites. Further, the protein and mRNA expression of genes related to the water balance pathway were measured. AB23A could significantly down-regulate the elevated protein and mRNA expression levels of aquaporin 2 (AQP2) and angiotensin Ⅱ type 1 receptor, and inhibit the transport of AQP2 to the apical plasma membrane induced by senecionine exposure. AB23A also significantly decreased serum levels of angiotensin Ⅱ. In vitro studies further confirmed that AB23A regulates AQP2 expression in renal inner medullary collecting duct cells 3 (IMCD3). These data indicate that AB23A regulates the expression of AQP2 in renal medulla, thereby affecting its water reabsorption in mice with senecionine-induced acute liver injury. This work achieves a better understanding of the diuretic effect of AR, and provides experimental foundation and theoretical basis for the treatment of PA-induced acute liver injury by AR in clinics.

Nicotinic acetylcholine receptors (nAChRs) belong to ligand-gated ion channel receptors, of which α7 nAChR subtype is widely distributed in the cerebral cortex, thalamus, hippocampus, and also identified in microglia, macrophages, bone marrow cells, etc. Previous studies revealed that α7 nAChR is closely related to the function of the cholinergic anti-inflammatory pathway, and is a vital target for drug development of Alzheimer's disease and schizophrenia. The establishment of a stable α7 nAChR in vitro drug screening system is crucial for the efficient screening of novel drugs targeting this target. Recombinant expression of different subtypes of nAChRs on Xenopus laevis oocyte membranes and current detected by two-electrode voltage clamp (TEVC) is an advanced and complex model for novel drug screening. Molecular chaperones can assist the assembly of some nAChR subunits to form functional receptors, providing a stable expression model for the screening of compounds targeting this receptor. In this study, a molecular chaperone gene of α7 nAChR, transmembrane protein 35A (Tmem35a), was isolated and cloned from rats. We constructed the recombinant expression vector and obtained the cRNA of Tmem35a by in vitro transcription technique. Two cRNAs (Tmem35a and α7) were mixed and injected into X. laevis oocytes for expression. Then, the effects of this molecular chaperone on the current expression and pharmacological properties of α7 nAChR were evaluated by the TEVC. The results revealed that TMEM35A, also known as novel acetylcholine receptor chaperone (NACHO) could effectively increase the expression of α7 nAChR protein on oocyte membranes, and the amount of α7 nAChR protein was increased about 1-fold. The peak current induced by agonist acetylcholine (ACh) was increased about 10-fold. After injection of Tmem35a cRNA, the median effect concentration (EC₅₀) value of α7 nAChR to agonist ACh is 228.5 μmol·L^-1, which shows almost no difference from native α7 nAChR (EC₅₀: 223.3 μmol·L^-1), indicating the preservation of the normal properties of α7 nAChR. The results of this investigation indicate that the molecular chaperone NACHO effectively assists the heterologous expression of α7 nAChR in X. laevis oocytes, which provides a model for screening the potency of lead compounds targeting α7 nAChR. All animal experiments in this study were reviewed and approved by the Ethics Committee of Guangxi University (approval number: GXU-2023-0249).

N-type voltage-gated calcium (Ca²⁺) channels (N-type VGCC, Ca_V2.2) mediate Ca²⁺ influx in response to action potential at the presynaptic terminal, and play an important role in synaptogenesis, neurotransmitter release and nociceptive signal transduction. It is a new target for the development of drugs for the treatment of neuralgia (chronic pain) and other major diseases. Due to the difficulty of calcium channel expression in vitro and the detection of channel current, there is a great lack of new drug screening models. In this study, we established and optimized the electrophysiological drug screening model using Xenopus laevis oocytes for the recombinant expression of Ca_V2.2 in vitro (this study were reviewed and approved by the Ethics Committee of Guangxi University, approval number: GXU-2023-0249). Firstly, the linear plasmids encoding cDNA of major subunit α1B and auxiliary subunits α2δ1 and β3 of rat Ca_V2.2 were used as templates for in vitro transcription to generate their related mRNA (cRNA), after which three kinds of cRNA were injected into Xenopus laevis oocytes at the mass ratio of 2∶1∶1 for expression. The two-electrode voltage clamp (TEVC) technique was used to detect the inward current produced by Ca_V2.2. At the same time, the expression conditions of Ca_V2.2 were optimized, and its gating function was characterized from the aspects of channel activation and inactivation. The results showed that 3-5 days after cRNA microinjection, stable Ca_V2.2-mediated barium ion (Ba²⁺) currents were successfully detected. The interference of endogenous potassium channels and Ca²⁺-activated chloride channels can be eliminated by tetraethylammonium hydroxide (TEAOH) and 1, 2-bis(2-aminophenoxy)ethane-N, N, N', N'-tetraacetic acid tetrakis (BAPTA-AM) treatment. The maximum potential for Ca_V2.2 activation is 0 mV, and the current reverses to be outward when the membrane potential is greater than +50 mV. By fitting the steady-state activation and inactivation curves, the half-maximal activation potential and half-maximal inactivation potential of Ca_V2.2 are identified as -15.9 and -60.2 mV. In this study, a stable Ca_V2.2 expression system was established based on Xenopus laevis oocytes. The in vitro expression system can provide a new way for the screening of Ca_V2.2 active compounds or lead drugs.

In this study, we investigated the anti-inflammatory effect and mechanism of tilianin in lipopolysaccharide (LPS)-induced RAW264.7 cells. The cell viability was detected by cell counting kit-8 (CCK-8) assay. The content of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) were detected by enzyme-linked immuno sorbent assay (ELISA) kits. The content of nitric oxide (NO) was assayed by Griess reagent method. The level of intracellular reactive oxygen species (ROS) was detected by 2', 7'-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescent probe. The protein levels of Toll like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (Myd88), nuclear factors κB p65 (NF-κB p65), phosphorylated nuclear factor κB p65 (p-NF-κB p65), nuclear factor κB inhibitory protein α (ⅠκBα) and phosphorylation nuclear factor κB inhibitory protein α (p-ⅠκBα) were detected by Western blot. The mRNA and protein levels of NLRP3, pro-IL-1β, pro-IL-18 and pro-caspase-1 were detected by qRT-PCR and Western blot. Immunofluorescence staining was used to detect the nuclear translocation of NF-κB p65. The effect of tilianin on the TLR4/Myd88/NF-κB signaling pathway was further validated by using the TLR4 signaling inhibitor restatorvid (TAK242). The results showed that tilianin significantly reduced the levels of TNF-α, IL-6 and NO in the supernatant of RAW264.7 cells and decreased the content of intracellular ROS. Tilianin reduced the levels of TLR4, Myd88, p-NF-κB p65 and p-ⅠκBα protein and nuclear translocation of NF-κB p65. Tilianin could reduce the protein levels of NLRP3, pro-IL-1β, pro-IL-18 and pro-caspase-1. Tilianin significantly inhibited the mRNA levels of NLRP3 and pro-IL-1β. The above research results indicated that tilianin could significantly alleviate the LPS-induced inflammatory response in RAW264.7 cells and its mechanism might be related to downregulate the TLR4/Myd88/NF-κB signaling pathway to inhibit NLRP3 inflammasome.