The aim of this study was to investigate the molecular mechanisms by which hypoxia affects the biological behavior of yak PASMCs, the changes in the histological structure of yak and cattle lungs, and the relationships and regulatory roles that exist regarding the differences in the distribution and expression of PDK1 and its hypoxia-associated factors screened for their role in the adaptation of yak lungs to the plateau hypoxic environment. The results showed that, at the level of transcriptome sequencing, the molecular regulatory mechanisms of the HIF-1 signaling pathway, glucose metabolism pathway, and related factors (HK2/PGK1/ENO1/ENO3/ALDOC/ALDOA) may be closely related to the adaptation of yaks to the hypoxic environment of the plateau; at the tissue level, the presence of filled alveoli and semi-filled alveoli, thicker alveolar septa and basement membranes, a large number of erythrocytes, capillary distribution, and collagen fibers accounted for all levels of fine bronchioles in the lungs of yaks as compared to cattle. A higher percentage of goblet cells was found in the fine bronchioles of yaks, and PDK1, HIF-1α, and VEGF were predominantly distributed and expressed in the monolayers of ciliated columnar epithelium in the branches of the terminal fine bronchioles of yak and cattle lungs, with a small amount of it distributed in the alveolar septa; at the molecular level, the differences in PDK1 mRNA relative expression in the lungs of adult yaks and cattle were not significant (p > 0.05), the differences in HIF-1α and VEGF mRNA relative expression were significant (p < 0.05), and the expression of PDK1 and HIF-1α proteins in adult yaks was stronger than that in adult cattle. PDK1 and HIF-1α proteins were more strongly expressed in adult yaks than in adult cattle, and the difference was highly significant (p < 0.01); the relative expression of VEGF proteins was not significantly different between adult yaks and cattle (p > 0.05). The possible regulatory relationship between the above results and the adaptation of yak lungs to the plateau hypoxic environment paves the way for the regulatory mechanisms of PDK1, HIF-1α, and VEGF, and provides basic information for studying the mechanism of hypoxic adaptation of yaks in the plateau. At the same time, it provides a reference for human hypoxia adaptation and a target for the prevention and treatment of plateau diseases in humans and plateau animals.

Madin–Darby Canine Kidney (MDCK) cells are a key cell line for influenza vaccine production, due to their high viral yield and low mutation resistance. In our laboratory, we established a tertiary cell bank (called M60) using a standard MDCK cell line imported from American Type Culture Collection (ATCC) in the USA. Due to their controversial tumourigenicity, we domesticated non-tumourigenic MDCK cells (named CL23) for influenza vaccine production via monoclonal screening in the early stage of this study, and the screened CL23 cells were characterised based on their low proliferative capacity, which had certain limitations in terms of expanding their production during cell resuscitation. It was thus our objective to enhance the proliferation efficiency of MDCK cells for influenza vaccine production following cell resuscitation, with a view to improving the production of non-tumourigenic MDCK cells for vaccines and enhancing the production of influenza virus lysate vaccines from MDCK cells through genetic intervention. We concentrated on the protein thrombosponin-1 (THBS1), which was markedly differentiated in the proteomics data of the two MDCK cells. By integrating this finding with related studies, we were able to ascertain that THBS1 exerts a significant influence on the level of cell proliferation and apoptosis. Consequently, our objective was to investigate the impact of THBS1 expression on MDCK cell apoptosis by verifying the differences in THBS1 expression between the two MDCK cells and by interfering with THBS1 expression in the MDCK cells. We found that the knockdown of THBS1 significantly increased the proliferation and apoptosis of CL23 cells without causing significant changes in cell migration and invasion, and its overexpression significantly decreased the proliferation of M60 cells and increased cell migration, invasion, and apoptosis. In addition, the TGF-β/Smad pathway target genes transforming growth factor-β1 (TGF-β1), mothers against decapentaplegic homolog 2 (Smad2), and mothers against decapentaplegic homolog 3 (Smad3), were significantly down-regulated in CL23 cells after THBS1 knockdown and up-regulated in M60 cells after overexpression, with consistent expression identified at both the mRNA and protein levels. The treatment of cells with TGF-β activators and inhibitors further demonstrated that THBS1 regulated MDCK cell proliferation and apoptosis through the TGF-β/Smad signalling pathway. Finally, we found that THBS1 also regulated H1N1 influenza virus replication. These findings enable a comprehensive understanding of the regulatory mechanisms of THBS1 regarding MDCK cell proliferation and apoptosis functions and the effects of influenza virus replication.

Veterinary practice faces rising antimicrobial resistance, driving interest in plant-derived alternatives. Purslane (Portulaca oleracea L.), a medicinal edible herb with antimicrobial, anti-inflammatory, and immunomodulatory properties, is a promising candidate. This narrative review synthesizes 160 studies into a unified framework linking chemical composition (flavonoids, alkaloids, polysaccharides, organic acids), pharmacological activities (12 major effects), and veterinary applications. Mechanistically, polysaccharides act as immunomodulators via the TLR4/MyD88 pathway; flavonoids (quercetin, kaempferol) exert antioxidant/anti-inflammatory effects through NF-κB/MAPK inhibition and Nrf2 activation; organic acid extracts show potent anti-MRSA activity (MIC 0.5–1.0 mg/mL); and alkaloids enhance insulin secretion. In vivo, dietary purslane at 2–3% improves broiler growth performance and feed conversion, while supplementation enriches omega-3 fatty acids in eggs and meat. However, translational barriers persist, including limited pharmacokinetic data, lack of large-scale field trials, and insufficient safety and residue-depletion information for food-producing animals. We outline future priorities, including species-specific pharmacokinetic studies, field efficacy trials, and quality-control standards, positioning purslane as a mechanism-rich, antibiotic-sparing candidate for further investigation in veterinary therapeutics and functional feed additives.