NBHA Reduces Acrolein-Induced Changes in ARPE-19 Cells: Possible Involvement of TGFβ

Abstract

Purpose Acrolein, a toxic, reactive aldehyde formed metabolically and environmentally, has been implicated in the damage to and dysfunction of the retinal pigment epithelium (RPE) that accompanies age-related macular degeneration (AMD). Our purpose was to investigate the potential of acrolein to influence the release of transforming growth factor beta-2 (TGFβ2) and vascular endothelial growth factor (VEGF), to assess the ability of N-benzylhydroxylamine (NBHA) to prevent the effect of acrolein on cytokine release and reduction of viable cells, and to explore the pathway by which acrolein might be causing the increase of VEGF. Materials and Methods Confluent ARPE-19 cells were treated with acrolein and/or NBHA. They were also pretreated with SIS3, a specific inhibitor of SMAD 3, and ZM39923, a JAK3 inhibitor, before being treated with acrolein. Viable cells were counted; ELISA was used to measure the TGFβ2 and/or VEGF in the conditioned media. Results Acrolein was shown to reduce the number of viable ARPE-19 cells and to upregulate the release of the proangiogenic cytokines TGFβ2 and VEGF. Co-treatment with 200 μM NBHA significantly reduced the effects of acrolein on viable cell number and TGFβ2 release. Pretreatment of the cells with SIS3 partially blocked the action of acrolein on decreased viable cell number and VEGF upregulation, suggesting that part of the effects of acrolein are mediated by the increased levels of TGFβ and its signaling. Conclusions Our results suggest that the action of acrolein on the reduction of viability and VEGF increase by ARPE-19 cells is partially mediated by TGFβ2. By reducing the effects of acrolein, NBHA and SIS3 could be potential pharmacological agents in the prevention and progression of acrolein-induced damage to the RPE that relates to AMD.

A Possible Role of Acrolein in Diabetic Retinopathy: Involvement of a VEGF/TGFβ Signaling Pathway of the Retinal Pigment Epithelium in Hyperglycemia

“…Furthermore, we found that acrolein increased levels of VEGF and TGFβ2 in the cell media of ARPE-19 cells, that the increase of TGFβ2 could be partially blocked by NBHA, and the increase in VEGF could be partially blocked by NBHA and the TGFβ pathway blocker SIS3 supporting the hypothesis that acrolein exerts its effects through modulation of the TGFβ pathway. 29 We now demonstrate that acrolein has a greater effect on reducing ARPE-19 cells in higher than in normal glucose levels and that this reduction in cell number can be modulated by co-administration of NBHA (sequestering the acrolein) which reduced the effects of the glucose concentration difference in cell viability. This is most likely due to the enhanced oxidizing effect of the higher glucose levels and is not unexpected considering the increased mitochondrial potential associated with hyperglycemia as evidenced by the work of Du et al 55 and Brownlee et al 56 Acrolein disrupted TGFβ and VEGF regulation by the remaining cells, causing each cell to contribute more of each cytokine to the CM, and this, too, could be mitigated by co-treatment with NBHA.…”

“…28 Our previous studies in normal glucose conditions concluded that NBHA and SIS3 are capable of reducing acrolein-mediated RPE cell death. 29 We also reported that the action of acrolein in the reduction of cell viability and the increase of VEGF are partially mediated by TGFβ2. 29 Acrolein, itself, though associated with diabetes complications and retinal degeneration in age-related macular degeneration has not been studied in the eyes of subjects with diabetes.…”

“…29 We also reported that the action of acrolein in the reduction of cell viability and the increase of VEGF are partially mediated by TGFβ2. 29 Acrolein, itself, though associated with diabetes complications and retinal degeneration in age-related macular degeneration has not been studied in the eyes of subjects with diabetes. We studied in vitro , using ARPE-19 cells cultured in low and high glucose media, the effect of acrolein on the production of TGFβ and VEGF, the ability of NBHA to prevent these effects of acrolein on cytokine release, its effect on cell viability, and explored the pathways by which acrolein causes an increase in VEGF synthesis.…”

Chemical Modification of Ginsenoside on Cell Viability and Cytokine Secretion

“…An over accumulation of glucose and/or fructose damages blood capillaries in the retina with fluid and lipids leakage to the macula, the region of the retina with high visual acuity. The fluid accumulation results in the swelling (or edema) of the macula, which blurs vision [10]. …”

Acrolein scavengers, cysteamine and <i>N</i>-benzylhydroxylamine, reduces the mouse liver damage after acetaminophen overdose

“…In this study, we determined the involvement of acrolein and examined two putative acrolein scavengers, a thiol compound cysteamine (CystE) and a hydroxylamine N -benzylhydroxylamine (NBHA), to identify novel therapeutic options for liver injury [17, 19]. Thiol and hydroxylamine trap aldehyde and decrease its toxicity [18].…”