Acta Pharmaceutica Sinica B

Targeting SARS-CoV-2 main protease for the discovery of a broad-spectrum COVID-19 inhibitor by intensive multi-tiered validation

Acta Pharmaceutica Sinica B. 2025, 15(11): 5789-5802.

SARS-CoV-2 and its emerging variants continue to pose a significant global public health threat. The SARS-CoV-2 main protease (Mpro) is a critical target for the development of antiviral agents that can inhibit viral replication and transcription. In this study, we identified chebulagic acid (CHLA), isolated from Terminalia chebula Retz., as a potent non-peptidomimetic and non-covalent Mpro inhibitor. CHLA exhibited intermolecular interactions and provided significant protection to Vero E6 cells against a range of SARS-CoV-2 variants, including the wild-type, Delta, Omicron BA.1.1, BA.2.3, BA.4, and BA.5, with EC₅₀ values below 2 μmol/L. Moreover, in vivo studies confirmed the antiviral efficacy of CHLA in K18-hACE2 mice. Notably, CHLA bound to a unique groove at the interface between Mpro domains I and II, which was revealed by the high-resolution crystal structure (1.4 Å) of the Mpro–CHLA complex, shrinking the substrate binding pocket of Mpro and inducing Mpro aggregation. CHLA was proposed to act as an allosteric inhibitor. Pharmacokinetic profiling and safety assessments underscore CHLA's potential as a promising broad-spectrum antiviral candidate. These findings report a novel binding site on Mpro and identify antiviral activity of CHLA, providing a robust framework for lead compounds discovery and elucidating the underlying molecular mechanisms of inhibition.

Engineered Escherichia coli Nissle 1917 targeted delivery of extracellular PD-L1-mFc fragment for treating inflammatory bowel disease

Yuhong Wang, Lin Hu, Lei Wang, Chonghai Zhang, Wenhao Shen, Hongli Yang, Min Li, Xin Zhang, Mengmeng Xu, Muxing Zhang, Kai Yang, Xiaopeng Tian

Acta Pharmaceutica Sinica B. 2025, 15(11): 6019-6033.

Inflammatory bowel disease (IBD) is an autoimmune disorder involving complex immune regulation, where balancing localized and systemic immunosuppression is a key challenge. This study aimed to enhance the therapeutic efficacy by engineering the probiotic Escherichia coli Nissle 1917 (EcN). We removed endogenous plasmids pMUT1 and pMUT2 from wild-type EcN and expressed the mPD-L1 (19‒238 aa)-mFc fusion protein on the bacterial surface using a cytolysin A (ClyA) fragment. This modification stabilized mPD-L1 (19‒238 aa) protein expression and promoted its recruitment to outer membrane vesicles (OMVs). The engineered strain, EcNΔpMUT₁/₂-ClyA-mPD-L1-mFc (EcN-ePD-L1-mFc), features conditional ePD-L1-mFc expression under the araBAD promoter, enhancing gut-targeted release and reducing systemic side effects. This strain improved treatment targeting and efficiency by enabling direct ePD-L1-mFc interaction with immune cells at inflammation sites. OMVs from this strain induced Treg proliferation, inhibited effector T cell proliferation in vitro, and significantly improved intestinal inflammation and colonic epithelial barrier repair in vivo. Additionally, the bacterium restored intestinal microbiota balance, increasing Lactobacillaceae and reducing Bacteroides. This study highlights the engineered bacterium’s potential for targeted intestinal immune modulation and offers a novel local IBD treatment approach with promising clinical prospects.

Microneedle-facilitated Portulaca oleracea L.-derived nanovesicles ameliorate atopic dermatitis by modulating macrophage M1/M2 polarization and inhibiting NF-κB and STING signaling pathways

Acta Pharmaceutica Sinica B. 2025, 15(11): 5966-5987.

Clinical management of atopic dermatitis (AD) is challenged by its susceptibility to recurrence, side effects, and high costs. We found that Portulaca oleracea L.-derived nanovesicles (PDNV) exert anti-inflammatory effects by modulating macrophage M1/M2 polarization. These effects were achieved through pathways including inhibition of nuclear factor-κB (NF-κB) and stimulator of interferon genes (STING) protein expression in diseased tissues, demonstrating their potential to ameliorate AD symptoms. To increase the transdermal permeation of PDNV, dissolvable microneedles composed primarily of hyaluronic acid (HA) were developed as an adjunctive means of delivery. Meanwhile, polysaccharides of Portulaca oleracea L., which were synergistic with PDNV, were used as microneedle constituent materials to enhance the mechanical properties and physical stability of HA. This new means of delivery significantly improves the treatment of AD and also provides new options for the efficient utilization of plant extracellular vesicles and the treatment of AD. In addition, transcriptomic analysis of PDNV showed that the mRNAs of Portulaca oleracea L. are closest to those of ferns, which may shed light on related evolutionary and plant species identification studies.

From single-thread delivery to cascading therapy: The promise of nanoCRISPR in solid tumors

Acta Pharmaceutica Sinica B. 2025, 15(11): 6089-6090.

CRTAC1 derived from senescent FLSs induces chondrocyte mitochondrial dysfunction via modulating NRF2/SIRT3 axis in osteoarthritis progression

Xiang Chen, Wang Gong, Pan Zhang, Chengzhi Wang, Bin Liu, Xiaoyan Shao, Yi He, Na Liu, Jiaquan Lin, Jianghui Qin, Qing Jiang, Baosheng Guo

Acta Pharmaceutica Sinica B. 2025, 15(11): 5803-5816.

Osteoarthritis (OA), the most prevalent joint disease of late life, is closely linked to cellular senescence. Previously, we found that the senescence of fibroblast-like synoviocytes (FLS) played an essential role in the degradation of cartilage. In this work, single-cell sequencing data further demonstrated that cartilage acidic protein 1 (CRTAC1) is a critical secreted factor of senescent FLS, which suppresses mitophagy and induces mitochondrial dysfunction by regulating SIRT3 expression. In vivo, deletion of SIRT3 in chondrocytes accelerated cartilage degradation and aggravated the progression of OA. Oppositely, intra-articular injection of adeno-associated virus expressing SIRT3 effectively alleviated OA progression in mice. Mechanistically, we demonstrated that elevated CRTAC1 could bind with NRF2 in chondrocytes, which subsequently suppresses the transcription of SIRT3 in vitro. In addition, SIRT3 reduction could promote the acetylation of FOXO3a and result in mitochondrial dysfunction, which finally contributes to the degradation of chondrocytes. To conclude, this work revealed the critical role and underlying mechanism of senescent FLSs-derived CRTAC1 in OA progression, which provided a potential strategy for the OA therapy.

DNAzyme targeting RIP3 suppresses NLRP3-mediated necroinflammation for the treatment of inflammatory diseases

Jiaxin Jia, Hugang Zhang, Guangxu Fang, Yang Li, Kai Wen, Hanyu Liu, Haobo Han, Quanshun Li

Acta Pharmaceutica Sinica B. 2025, 15(11): 5908-5932.

Necroptosis, a form of programmed cell death, initiates a series of biological responses and further culminates in necroinflammatory processes, consequently limiting the efficacy of cytokine antagonists in treating inflammatory diseases. To address this issue, DNAzyme R3-Dz specifically targeting receptor-interacting protein kinase 3 (RIP3) mRNA, a necrosome component, has been successfully developed and studied to elucidate the mechanism in cleaving its target mRNA. Then a polyamidoamine (PAMAM) derivative was constructed through the modification of nucleobase analog (termed AP) to achieve the R3-Dz delivery to macrophages. The AP/R3-Dz nanoparticles effectively downregulated the RIP3 expression, leading to subsequent decrease in the levels of reactive oxygen species (ROS) and damage-associated molecular patterns (DAMPs), ultimately inhibiting the necroinflammatory processes mediated by the NOD-like receptor family pyrin domain-containing 3 (NLRP3). Finally, AP/R3-Dz nanoparticles and their combination with the NLRP3 inhibitor MCC950 suppressed the necrotic phenotype and ameliorated the disease progression in diverse models, including gouty arthritis, autoimmune hepatitis and rheumatoid arthritis. In summary, the AP/R3-Dz nanoparticles in combination with MCC950 have been demonstrated to achieve the intervention in necroptosis and inflammation by dual disruption of the intricate feedback loop of necroinflammation and thus have promising potential in the treatment of inflammatory diseases.

A self-cascade nanoCRISPR prompts transcellular penetration to potentiate gene editing and tumor killing

Chao Liu, Yangsong Xu, Ning Wang, Hongyu Liu, Xi Yang, Shiyao Zhou, Dongxue Huang, Yingjie Li, Yanjie You, Qinjie Wu, Changyang Gong

Acta Pharmaceutica Sinica B. 2025, 15(11): 5933-5944.

CRISPR/Cas9-based therapeutics face significant challenges in penetrating the dense microenvironment of solid tumors, resulting in insufficient gene editing and compromised treatment efficacy. Current nanostrategies, which mainly focus on the paracellular pathway attempted to improve gene editing performance, whereas their efficiency remains uneven in the heterogenous extracellular matrix. Here, the nanoCRISPR system is prepared with self-cascading mechanisms for gene editing-mediated robust apoptosis and transcellular penetration. NanoCRISPR unlocks its self-cascade capability within the matrix metallopeptidase 2-enriched tumor microenvironment, initiating the transcellular penetration. By facilitating cellular uptake, nanoCRISPR triggers robust apoptosis in edited malignancies, promoting further transcellular penetration and amplifying gene editing in neighboring tumor cells. Benefiting from self-cascade between robust apoptosis and transcellular penetration, nanoCRISPR demonstrates continuous gene transfection/tumor killing performance (transfection/apoptosis efficiency: 1st round: 85%/84.2%; 2nd round: 48%/27%) and homogeneous penetration. In xenograft tumor-bearing mice, nanoCRISPR treatment achieves remarkable anti-tumor efficacy (∼83%) and significant survival benefits with minimal toxicity. This strategy presents a promising paradigm emphasizing transcellular penetration to enhance the effectiveness of CRISPR-based antitumor therapeutics.

Protein degradation-based anti-infective drug research

Acta Pharmaceutica Sinica B. 2025, 15(11): 6076-6081.

Orally deliverable biomimetic nucleic acid therapies for targeted treatment of atherosclerosis

Acta Pharmaceutica Sinica B. 2025, 15(11): 6052-6069.

Accumulating evidence has demonstrated that nucleic acid-based therapies are promising for atherosclerosis. However, nearly all nucleic acid delivery systems developed for atherosclerosis necessitate injection, which results in rapid elimination and poor patient compliance. Consequently, oral delivery strategies capable of targeting atherosclerotic plaques are imperative for nucleic acid therapeutics. Herein we report the development of yeast-derived capsules (YCs) packaging an antisense oligonucleotide (AM33) targeting microRNA-33 (miR-33) for the oral treatment of atherosclerosis. YCs provide stability for AM33, preventing its premature release in the gastrointestinal tract. AM33-containing YCs, defined as YAM33, showed high transfection in macrophages, thus promoting cholesterol efflux and inhibiting foam cell formation by regulating the target genes/proteins of miR-33. Orally delivered YAM33 effectively accumulated within atherosclerotic plaques in ApoE⁻/⁻ mice, primarily by transepithelial absorption via M cells in Peyer's patches and subsequent translocation via macrophages through the lymphatic system. Inhibition of miR-33 by oral YAM33 significantly delayed the progression of atherosclerosis. Moreover, oral treatment with YCs co-delivering AM33 and atorvastatin afforded significantly enhanced anti-atherosclerotic effects. Our findings suggest that yeast-based microcapsules represent an effective carrier for oral delivery of nucleic acids, either alone or in combination with existing drugs, offering a promising approach for precision therapy of atherosclerotic diseases.

Amino acid restriction in obesity management: Inducing energy discharge

Acta Pharmaceutica Sinica B. 2025, 15(11): 6073-6075.