Renmin Hospital of Wuhan University

Covalent inhibitors have re-emerged as powerful therapeutic agents, offering the ability to modulate "undruggable" proteins including oncogenic drivers that have eluded traditional drug discovery efforts. Expanding the repertoire of electrophilic moieties remains a critical frontier in covalent drug discovery. Here, we report a Rh(I)-catalyzed cycloisomerization of N-allyl bicyclo[1.1.0]butane amides (BCB amides) to access the 5-methylene-3-azabicyclo[5.1.0]octan-4-one (MABO) scaffold via strain-release reactivity. Both N-allyl BCB amides and MABOs can react with nucleophiles, highlighting their potential as electrophilic moieties for covalent drug design. Kinetic assays against glutathione revealed that selected N-allyl BCB amides and MABOs exhibit half-lives comparable to that of (±)-sotorasib, whose enantiomerically pure form received FDA approval as an anticancer drug. Biological evaluation in human-derived head and neck squamous cell carcinoma (HNSCC) models identified specific BCB amides and MABO compounds capable of modulating cancer cell growth. The toxicity of the compounds was evaluated by flow cytometry in human peripheral blood mononuclear cells (PBMCs) and by monitoring LDH release in the monocytic cell line THP-1, both under basal and activated conditions. Together, these findings suggest that BCB amides and MABOs represent promising classes of electrophilic scaffolds for covalent drug discovery.

Innate immune responses must be coordinated with the cellular metabolic state. The intracellular pattern recognition receptor NOD1 detects bacterial peptidoglycans and initiates signaling from cellular membranes, a process regulated by ZDHHC5-mediated palmitoylation. Using biochemical analyses and immune-competent cell models, we show that AMP-activated protein kinase (AMPK) integrates metabolic cues into NOD1 signaling by regulating ZDHHC5. AMPK phosphorylates ZDHHC5 at Ser296 and Ser380, weakens its association with Golga7B, and promotes its displacement from the plasma membrane, thereby reducing NOD1 palmitoylation, membrane localization, and downstream signaling. Conversely, stimulation with the NOD1 agonist C12-iE-DAP suppresses AMPK activity, stabilizing ZDHHC5 at the membrane and sustaining NOD1 activation. These findings define a reciprocal regulatory circuit linking metabolic stress sensing and innate immune signaling, and illustrate how metabolic pathways govern the spatial control of pattern recognition receptors in innate immunity.

Endocrine and metabolic diseases exhibit considerable diversity, with clinical manifestations affecting virtually all body systems. Consequently, teaching in this field is highly specialized, posing significant challenges for students to master. It is worthwhile to discuss approaches to improving the teaching quality in endocrinology and metabolism. This study investigates the impact of integrating clinical pathway with representative cases studies on resident education in the department of endocrinology and metabolism. From January 2021 to January 2022, a total of 87 residents who received standardized training in the department of endocrinology and metabolism at our hospital were randomly assigned to either the traditional teaching method group or the clinical pathway combined with case-based teaching group. Upon joining the department, all students training in teaching methodologies, and their professional knowledge was systematically assessed and evaluated. At the conclusion of the four-week training program, students underwent a comprehensive reassessment, evaluation, and survey. This study demonstrated that, compared with the traditional teaching method, the integration of clinical pathway and case-based teaching significantly improved students’ theoretical examination scores (p < 0.001) and Mini-CEX assessment scores (p < 0.001), as well as enhanced trainees’ overall satisfaction with their instructors (p < 0.01). Additionally, students in the group integrating clinical pathway and case-based teaching methods reported higher satisfaction with the teaching approach compared to those in the traditional teaching group (p = 0.000). Furthermore, the integration of clinical pathway and case-based teaching method has significantly enhanced students’ satisfaction with instruction (χ2 = 7.85, p = 0.005). It is suggested that the integration of clinical pathway with case-based teaching appears to be more beneficial and effective than traditional teaching method in enhancing the academic performance and clinical competencies of residents undergoing standardized training, while also yielding higher levels of students’ satisfaction.

1,4-Dinitrosopiperazine (DNP), a nitrite-derived compound widely found in Cantonese-style salted fish, induces malignant transformation of nasopharyngeal epithelial cells, but its tissue specificity and carcinogenic mechanisms remain unclear. In this study, tree shrews were used to investigate the tissue specificity and carcinogenic mechanisms of DNP. A pathological atlas of tree shrew nasopharyngeal tissue was constructed via anatomical and pathological examination. Pharmacokinetics and tissue affinity were assessed through single-dose administration, quantifying blood/tissue distribution via liquid chromatography-tandem mass spectrometry‌ (LC‒MS/MS). Chronic intervention was established via 12-month DNP exposure, with micro positron emission tomography/computed tomography (PET-CT) imaging and pathology confirming malignant transformation. Network toxicology analyzed DNP-associated head/neck carcinomas, followed by qPCR validation of key mechanisms. A three-dimensional reconstruction model and tissue atlas of the tree shrew nasopharynx were developed. LC-MS/MS analysis revealed peak DNP accumulation in the nasopharynx at 24 h post-injection (with significantly higher retention compared to other tissues), followed by complete systemic clearance within 72 h. After 12-month chronic DNP intervention, microPET/CT imaging and pathological examination confirmed precancerous lesions or malignant transformation in nasopharyngeal tissues of all tree shrews. Network toxicology highlighted cytochrome P450 (CYP450) enzyme activation as closely associated with malignant progression, with CYP19A1 (HR = 1.52) and CYP2D6 (HR = 0.745) expression showing significant prognostic relevance. qPCR validation demonstrated marked CYP19A1 upregulation and CYP2D6 downregulation in animal nasopharyngeal tissues, indicating their role as key pathogenic biomarkers. These findings confirm DNP’s selective nasopharyngeal accumulation drives carcinogenesis via CYP450 activation, with CYP19A1 overexpression and CYP2D6 suppression may serve as key pathogenic biomarkers and potential regulatory factors in DNP-induced malignant nasopharyngeal transformation.

Acute lung injury (ALI) is a clinically prevalent condition characterized by excessive inflammatory activation leading to tissue damage, with high mortality rates. USP19, a deubiquitinase (DUB) known to play critical roles in skeletal muscle atrophy, antiviral responses, and stabilization of transmembrane endoplasmic reticulum-associated degradation (ERAD) substrates, has not been previously investigated in ALI pathogenesis. In this study, we established both in vivo (lipopolysaccharide (LPS)-challenged C57BL/6j mice) and in vitro (LPS-stimulated HULEC-5a cells) to simulate acute lung injury (ALI), demonstrating significant downregulation of USP19 expression during ALI progression. Functional studies revealed that genetic ablation of USP19 in mice exacerbated LPS-induced acute lung injury, manifesting as enhanced pulmonary tissue damage, increased vascular permeability, amplified inflammatory responses, and elevated cellular apoptosis. In HULEC-5a cells, USP19 overexpression attenuated LPS-induced cellular damage, inflammatory activation and apoptosis, while USP19 knockdown exacerbated these effects. These findings were recapitulated in USP19-knockout mouse lung microvascular endothelial cells. Mechanistically, we identified that USP19 exerts its protective effects by suppressing TAK1 phosphorylation, thereby inhibiting activation of the downstream JNK/p38 signaling pathway. These findings not only elucidate USP19 as a novel negative regulator of ALI through modulation of the TAK1-JNK/p38 axis, but also provide potential therapeutic targets and conceptual advances for ALI treatment strategies.