Antioxidants reduce TGF‐beta2‐induced gene expressions in human optic nerve head astrocytes

Abstract

ABSTRACT.Purpose: The goal of the present study was to investigate whether the antioxidants vitamin E, vitamin C and vitamin B1 can reduce the transforming growth factor-beta2 (TGF-b2)-induced gene expressions in cultured human optic nerve head (ONH) astrocytes. Methods: Cultured human ONH astrocytes were pretreated with different concentrations of vitamin E, vitamin C and vitamin B1 and then exposed to 1.0 ng ⁄ ml TGF-b2 for 24 hr. Expression of the heat shock proteins Hsp27 and aB-crystallin, the extracellular matrix (ECM) component fibronectin and the ECM-modulating protein connective tissue growth factor (CTGF) was detected by immunohistochemistry or real-time PCR analysis. Results: TGF-b2 increased the expression of Hsp27, aB-crystallin, fibronectin and CTGF in human ONH astrocytes. Pretreatment with different concentrations of vitamin E, vitamin C and vitamin B1 reduced the TGF-b2-stimulated gene expressions. Conclusion: In cultured human ONH astrocytes, the TGF-b2-stimulated gene expressions could be reduced by pretreatment with vitamin E, vitamin C and vitamin B1. Therefore, the use of antioxidants in glaucomatous optic neuropathy might be a promising approach to prevent TGF-b2-induced cellular changes in ONH astrocytes.

Glia–neuron interactions in the mammalian retina

“…Gene expression dependent on TGF-b2 activation in astrocytes cultured from the optic nerve head is reduced after antioxidant treatment, indicating that antioxidants may have a place in the treatment of neurodegenerative diseases like glaucoma (Yu and Welge-Lussen, 2013). Astrocytes undergo morphological changes related to the damage produced in RGCs (Lye- Barthel et al, 2013).…”

Crystallins and neuroinflammation: The glial side of the story

“…Analogous to microglia, α-crystallin expression increases during or following activation of astrocytes suggesting a role for the chaperones in regulating the function of reactive astrocytes in response to stress including pro-inflammatory signals. Expression of α-crystallins, as well as other heat shock chaperones, can be induced in astrocytes by cytokines including TNF-α, TGF-β2, and several members of the interleukin family[25–27]. Induced expression by pro-inflammatory cytokines, in conjunction with their upregulation in diabetic retinopathy and MS suggests an important role for α-crystallins in the ongoing activation of astrocytes during chronic, pathological neuroinflammation.…”