Inhibition of TGF-β2-induced migration and epithelial-mesenchymal transition in ARPE-19 by sulforaphane

Vitamin D and Sulforaphane Decrease Inflammatory Oxidative Stress and Restore the Markers of Epithelial Integrity in an In Vitro Model of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is strictly linked to chronic oxidative stress, inflammation, loss of epithelial barrier integrity, and often with abnormal new blood vessel development. In this study, the retinal epithelial cell line ARPE-19 was treated with pro-inflammatory transforming growth factor-beta (TGF-β) to investigate the activity of vitamin D (VD) and sulforaphane (SF) in abating the consequences of oxidative stress and inflammation. The administration of VD and SF lowered reactive oxygen species (ROS) levels, and abated the related expression of the pro-inflammatory cytokines interleukin-6 and interleukin-8 induced by TGF-β. We evaluated mitochondrial respiration as a source of ROS production, and we discovered that the increased transcription of respiratory elements triggered by TGF-β was prevented by VD and SF. In this model of inflamed epithelium, the treatment with VD and SF also reduced the secretion of VEGF, a key angiogenic factor, and restored the markers of epithelial integrity. Remarkably, all the observed biological effects were potentiated by the co-stimulation with the two compounds and were not mediated by VD receptor expression but rather by the ERK 1/2 pathway. Altogether, the results of this study reveal the powerful synergistic anti-inflammatory activity of SF and VD and lay the foundation for future clinical assessment of their efficacy in AMD.

17β-estradiol inhibits TGF-β-induced collagen gel contraction mediated by human Tenon fibroblasts via Smads and MAPK signaling pathways

AIM

To investigate the impact of 17β-estradiol on the collagen gels contraction (CGC) and inflammation induced by transforming growth factor (TGF)-β in human Tenon fibroblasts (HTFs).

METHODS

HTFs were three-dimensionally cultivated in type I collagen-generated gels with or without TGF-β (5 ng/mL), 17β-estradiol (12.5 to 100 µmol/L), or progesterone (12.5 to 100 µmol/L). Then, the collagen gel diameter was determined to assess the contraction, and the development of stress fibers was analyzed using immunofluorescence staining. Immunoblot and gelatin zymography assays were used to analyze matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) being released into culture supernatants. Enzyme-linked immunosorbent assay (ELISA) and reverse transcription-quantitative polymerase chain reaction (RT-PCR) were used to detect interleukin (IL)-6, monocyte chemoattractant proteins (MCP)-1, and vascular endothelial growth factor (VEGF) in HTFs at the translational and transcriptional levels. The phosphorylation levels of Sma- and Mad-related proteins (Smads), mitogen-activated protein kinases (MAPKs), and protein kinase B (AKT) were measured by immunoblotting. Statistical analysis was performed using either the Tukey-Kramer test or Student's unpaired t-test to compare the various treatments.

RESULTS

The CGC caused by TGF-β in HTFs was significantly inhibited by 17β-estradiol (25 to 100 µmol/L), and a statistically significant difference was observed when comparing the normal control group with 17β-estradiol concentrations exceeding 25 µmol/L (P<0.05). The suppressive impact of 17β-estradiol became evident 24h after administration and peaked at 72h (P<0.05), whereas progesterone had no impact. Moreover, 17β-estradiol attenuated the formation of stress fibers, and the production of MMP-3 and MMP-1 in HTFs stimulated by TGF-β. The expression of MCP-1, IL-6, and VEGF mRNA and protein in HTFs were suppressed by 100 µmol/L 17β-estradiol (P<0.01). Additionally, the phosphorylation of Smad2 Smad3, p38, and extracellular signal-regulated kinase (ERK) were downregulated (P <0.01).

CONCLUSION

17β-estradiol significantly inhibits the CGC and inflammation caused by TGF-β in HTFs. This inhibition is likely related to the suppression of stress fibers, inhibition of MMPs, and attenuation of Smads and MAPK (ERK and p38) signaling. 17β-estradiol may have potential clinical benefits in preventing scar development and inflammation in the conjunctiva.

Study on the Correlation between the Levels of HtrA3 and TGF-β2 in Late Pregnancy and Preeclampsia

Preeclampsia (PE) is a common and proprietary complication during pregnancy. The correlation was found between the levels of HtrA3 and TGF-β 2 and preeclampsia (PE). This study aimed to detect the HtrA3 and TGF-β2 in different parts of the third trimester (maternal serum, placenta). The 102 pregnant women who were eligible for enrollment in the obstetric examination at Tengzhou Maternity and Child Health Hospital from June 2020 to December 2020 were selected as the research objects. 28 cases diagnosed with PE were set up as the observation group 1, and 24 cases diagnosed with severe PE were set up as the observation group 2. Select 50 normal pregnant women as the control group and research the expressions of HtrA3 and TGF-β2 in maternal blood and placental tissues of patients with PE. ELISA was used to measure the concentration of HtrA3 and TGF-β2 in maternal blood. The distribution of HtrA3 and TGF-β2 in the placenta was observed by immunohistochemical techniques (IHC) and mean optical density value (MOD). S/D was measured by using color Doppler ultrasonic. The concentration of HtrA3 and TGF-β2 in the maternal blood and placenta tissue was higher in severe PE compared with PE and normotensive pregnancy, respectively (P < 0.05). There is a negative correlation between the level of HtrA3 and TGF-β2 and the birthweight of newborns both in maternal plasma and placenta tissue in preeclampsia and positive correlation between HtrA3 and TGF-β2 levels and S/D. HtrA3 and TGF-β2 may correlate with severity of PE and their neonatal adverse outcomes.