A Nanoparticle Delivery of Plasmid Encoding Hepatocyte Growth Factor for Gene Therapy of Silicosis in Mice.

PURPOSE: Silicosis is a serious occupational disease that is characterized by pulmonary infiltrates and fibrosis and is often refractory to current treatments. New therapeutic strategies for silicosis are needed. Hepatocyte growth factor (HGF) is a latent anti-inflammatory and anti-fibrotic growth factor. METHODS: We prepared a polyethyleneimine-polyethylene glycol/pHGF/hyaluronic acid (PEG-PEI/pHGF/HA) nanomaterials loaded with plasmid DNA encoding HGF gene to increase its transfection efficiency. The characterization, including DNA entrapment efficiency, morphology, particle size, and zeta-potential of PEG-PEI/pHGF/HA was studied. And a PEG-PEI/pHGF/HA (N/P=30:1) nanoparticle with low toxicity and high transfection efficiency was used in treatment for silicosis in mice. RESULTS: The results showed that the human HGF expression in the lungs of the mice was increased, and the inflammatory cell infiltration and fibrous collagen deposition was significantly reduced. CONCLUSION: Therefore, PEG-PEI/pHGF/HA nanoparticle warrant further investigation and may be a potential therapeutic strategy for silicosis.

Local Multiple-site Injections of a Plasmid Encoding Human MnSOD Mitigate Radiation-induced Skin Injury by Inhibiting Ferroptosis.

BACKGROUND: Most patients who undergo radiotherapy develop radiation skin injury, for which effective treatment is urgently needed. MnSOD defends against reactive oxygen species (ROS) damage and may be valuable for treating radiation-induced injury. Here, we (i) investigated the therapeutic and preventive effects of local multiple-site injections of a plasmid, encoding human MnSOD, on radiation-induced skin injury in rats and (ii) explored the mechanism underlying the protective effects of pMnSOD. METHODS: The recombinant plasmid (pMnSOD) was constructed with human cytomegalovirus (CMV) promoter and pUC-ori. The protective effects of pMnSOD against 20-Gy X-ray irradiation were evaluated in human keratinocytes (HaCaT cells) by determining cell viability, ROS levels, and ferroptosisrelated gene expression. In therapeutic treatment, rats received local multiple-site injections of pMnSOD on days 12, 19, and 21 after 40-Gy γ-ray irradiation. In preventive treatment, rats received pMnSOD injections on day -3 pre-irradiation and on day 4 post-irradiation. The skin injuries were evaluated based on the injury score and pathological examination, and ferroptosis-related gene expression was determined. RESULTS: In irradiated HaCaT cells, pMnSOD transfection resulted in an increased SOD2 expression, reduced intracellular ROS levels, and increased cell viability. Moreover, GPX4 and SLC7A11 expression was significantly upregulated, and erastin-induced ferroptosis was inhibited in HaCaT cells. In the therapeutic and prevention treatment experiments, pMnSOD administration produced local SOD protein expression and evidently promoted the healing of radiation-induced skin injury. In the therapeutic treatment experiments, the injury score in the high-dose pMnSOD group was significantly lower than in the PBS group on day 33 post-irradiation (1.50 vs. 2.80, P < 0.05). In the prevention treatment experiments, the skin injury scores were much lower in the pMnSOD administration groups than in the PBS group from day 21 to day 34. GPX4, SLC7A11, and Bcl-2 were upregulated in irradiated skin tissues after pMnSOD treatment, while ACSL4 was downregulated. CONCLUSION: The present study provides evidence that the protective effects of MnSOD in irradiated HaCaT cells may be related to the inhibition of ferroptosis. The multi-site injections of pMnSOD had clear therapeutic and preventive effects on radiation-induced skin injury in rats. pMnSOD may have therapeutic value for the treatment of radiation-induced skin injury.

A recombinant plasmid encoding human hepatocyte growth factor promotes healing of combined radiation-trauma skin injury involved in regulating Nrf2 pathway in mice.

Combined radiation-trauma skin injury represents a severe and intractable condition that urgently requires effective therapeutic interventions. In this context, hepatocyte growth factor (HGF), a multifunctional growth factor with regulating cell survival, angiogenesis, anti-inflammation and antioxidation, may be valuable for the treatment of combined radiation-trauma injury. This study investigated the protective effects of a recombinant plasmid encoding human HGF (pHGF) on irradiated human immortalized keratinocytes (HaCaT) cells in vitro, and its capability to promote the healing of combined radiation-trauma injuries in mice. The pHGF radioprotection on irradiated HaCaT cells in vitro was assessed by cell viability, the expression of Nrf2, Bcl-2 and Bax, as well as the secretion of inflammatory cytokines. In vivo therapeutic treatment, the irradiated mice with full-thickness skin wounds received pHGF local injection. The injuries were appraised based on relative wound area, pathology, immunohistochemical detection, terminal deoxynucleotidyl transferase dUTP nick end labelling assay and cytokine content. The transfection of pHGF increased the cell viability and Nrf2 expression in irradiated HaCaT cells. pHGF also significantly upregulated Bcl-2 expression, decreased the Bax/Bcl-2 ratio and inhibited the expression of interleukin-1ß and tumor necrosis factor-α in irradiated cells. Local pHGF injection in vivo caused high HGF protein expression and noticeable accelerated healing of combined radiation-trauma injury. Moreover, pHGF administration upregulated Nrf2, vascular endothelial growth factor, Bcl-2 expression, downregulated Bax expression and mitigated inflammatory response. In conclusion, the protective effect of pHGF may be related to inhibiting apoptosis and inflammation involving by upregulating Nrf2. Local pHGF injection distinctly promoted the healing of combined radiation-trauma injury and demonstrates potential as a gene therapy intervention for combined radiation-trauma injury in clinic.

Social equity perception and public mental health: a Chinese study with panel data.

BACKGROUND: Mental health is a vital part of an individual's overall health and well-being, and the relationship between society and individuals has always been a focus of academic and public attention. However, the effect of social equity perceptions on individual mental health remains unclear. METHODS: Data were collected from 8,922 survey respondents with an average age of 47.533 years from the China Labor-force Dynamics Survey 2016 and 2018. The Center for Epidemiological Studies Depression scale was used to assess mental health. A two-way fixed effects regression model was used to determine the association between social equity perception and individual mental health. RESULTS: Individuals with higher perceptions of social equity were more likely to report better mental health ([Formula: see text] = -0.944, p < 0.01). Happiness, life satisfaction, and social trust partially play mediating roles in the relationship between social equity perception and individual mental health, while education and age play moderating roles. CONCLUSION: Social equity perception is a vital factor that affects mental health. Public policies should focus on helping less educated and older people improve their social equity perception to improve their mental health.