Chao Cui, Shuai Gao, Jingfei Shi, Kai Wang. Gut and Liver -0001;0:. https://doi.org/10.5009/gnl240539

Silk protein, as a natural polymer material with unique structures and properties, exhibits tremendous potential in the biomedical field. Given the limited production and restricted properties of natural silk proteins, molecular biotechnology has been extensively applied in silk protein genetic engineering to produce novel silk proteins with specific properties. This review outlines the roles of major model organisms, such as silkworms and spiders, in silk protein production, and provides a detailed introduction to the applications of gene editing technologies (eg, CRISPR-Cas9), transgenic expression technologies, and synthetic biology techniques in silk protein genetic engineering. By analyzing the genetic factors influencing silk protein expression, this review further elaborates on the innovative applications of silk proteins in drug delivery systems, tissue engineering and regenerative medicine (eg, skin, bone, cartilage, and vascular repair), as well as antibacterial immune strategies. Notably, modified silk proteins expressed by transgenic silkworms demonstrate significant advantages in enhancing drug bioavailability and promoting cell proliferation and differentiation. In conclusion, silk protein gene engineering, through continuous innovations in molecular biotechnology, has provided an effective pathway for the production of high-performance silk protein materials. The extensive applications of these modified silk proteins in the biomedical field have not only expanded the functionality of silk proteins but also offered new approaches to address medical challenges. In the future, the development of silk protein gene engineering will further rely on interdisciplinary integration to promote in-depth research and the expansion of industrial applications of silk proteins.

Myocardial ischemia‒reperfusion injury is a severe cardiovascular disease, and its treatment and prevention are crucial for improving patient prognosis and reducing the economic burden. This study aimed to explore the impact of hydrogen (H₂) on hypoxia/reoxygenation (H/R) injury in H9c2 cells (derived from rat embryonic heart tissue) induced by hydrogen peroxide (H₂O₂) and to elucidate its underlying mechanism. An H/R injury model was established in H9c2 cells via exposure to 15 μM H₂O₂ for 3 hours, followed by incubation in a 5% CO₂ atmosphere at 37°C for 24 hours. Then, the cells were treated with H₂ (50%) for 6, 12 or 24 hours. The results demonstrated that H9c2 cells exposed to H₂O₂ and subjected to H/R injury presented a marked decrease in the cell survival rate, accompanied by severe morphological alterations, such as curling and wrinkling, and elevated lactate dehydrogenase levels. Notably, H₂ mitigated H/R injury induced by H₂O₂ in a time-dependent manner, improving the morphological damage observed in H9c2 cells and decreasing lactate dehydrogenase levels. Compared with the model group, treatment with H₂ increased the activities of antioxidant enzymes, including catalase, superoxide dismutase, and glutathione peroxidase, while concurrently reducing the level of malondialdehyde, an indicator of cellular damage. Furthermore, H₂ treatment downregulated the expression of inflammatory cytokines and inflammatory-related factors, specifically interleukin-6, high-mobility group box 1, tumor necrosis factor-alpha, and Toll-like receptor 4, in H9c2 cells post-H/R injury. Furthermore, H₂ treatment resulted in a marked decrease in the expression levels of proteins associated with the Wnt/C-X3-C-motif receptor 1 signaling pathway, such as β-catenin, glycogen synthase kinase-3 beta, adenomatous polyposis coli, and Wnt and C-X3-C-motif receptor 1. This observation suggests a potential mechanism for its protective effects against H/R injury. Therefore, H₂ exerts a protective effect against H/R injury in H9c2 cells induced by H₂O₂, potentially by inhibiting the activated Wnt/C-X3-C-motif receptor 1 signaling pathway. This inhibition, in turn, prevents the generation of oxidative stress, inflammatory cytokines, and inflammation-associated factors.

This review systematically elucidates the molecular mechanisms and therapeutic potential of nuclear factor erythroid 2-related factor (Nrf) family members in the cardiovascular system. As critical components of the CNC-bZIP transcription factor family, the Nrf family (including Nrf-2/NFE2L2, Nrf-1/NFE2L1, and Nrf-3/NFE2L3) orchestrates antioxidant response element (ARE)-dependent gene expression networks, playing pivotal roles in maintaining redox homeostasis, modulating inflammatory responses, improving mitochondrial function, and regulating programmed cell death (apoptosis, autophagy, and pyroptosis). Clinical data have demonstrated that in patients with myocardial infarction, the expression of Nrf-3 gene is significantly upregulated in myocardial cells within the infarcted area. Its high expression is associated with increased in-hospital mortality during the acute phase and accelerated progression of ventricular remodeling. Knockout of the Nrf-3 gene can reduce the acute-phase mortality of myocardial infarction, improve ventricular remodeling, and enhance cardiac function. Additionally, a crossover trial involving 19 participants showed that after 2 months of administration of olive oil by-product pâté tablets, the plasma Nrf-2 level in the subjects increased by 88.9% with concurrent improvement in cardiovascular risk factors. Collectively, these findings confirm the impact of the Nrf family on cardiovascular prognosis and its potential for intervention. Furthermore, we comprehensively analyze the regulatory functions of Nrf members in major cardiovascular pathologies, including myocardial ischemia-reperfusion injury, atherosclerotic plaque formation/stabilization, and heart failure progression. Based on recent advances, we also discuss innovative therapeutic strategies targeting the Nrf pathway, encompassing pharmacological activators, gene/epigenetic therapies, combinatorial approaches, and lifestyle interventions, thereby providing a theoretical framework and novel perspectives for the precision medicine of cardiovascular diseases.