Top

BMC Ophthalmology

Published in:

01-12-2020 | Diabetic Retinopathy | Research article

The expression and significance of mTORC1 in diabetic retinopathy

Authors: Yanli Liu, Yarong Zheng, Yekai Zhou, Yi Liu, Mengxuan Xie, Wenjing Meng, Meixia An

Published in: BMC Ophthalmology | Issue 1/2020

Abstract

Background

To investigate the expression and significance of mechanistic target of rapamycin complex 1(mTORC1) in diabetic retinopathy (DR), and to find new targets and new methods for the treatment of DR.

Methods

A DR rat model was prepared by general feeding combined with intraperitoneal injection of 10% streptozotocin (60 mg/kg). The rats were randomly divided into a control group (NDM group) and a diabetes group (DM group). Three months later, the degrees of retinopathy was determined using hematoxylin and eosin staining, and the levels of p-S6, VEGF, and PEDF proteins were detected by immunohistochemistry and western blotting. Human retinal capillary endothelial cells (HRCECs) were cultured in high glucose (HG) conditions, then treated with rapamycin or transfected with siTSC1.The protein levels of p-S6 were assessed by western blotting. The 5-ethynyl-2′-deoxyuridine assay was used to detect cell proliferation, and the Transwell assay was used to detect cell migration.

Results

A DM rat model was successfully developed. The expressions of p-S6 and VEGF proteins were significantly increased in the DM group (p < 0.05), and the expression of PEDF protein was significantly decreased compared with the NDM group (p < 0.05). In vitro, the p-S6 protein, as well as cell proliferation and migration, in HG induced HRCECs were increased (p < 0.05) compared with the control (normal glucose) group (p < 0.05). After transfection with siTSC1 to activate mTORC1, the expression of p-S6, as well as cell proliferation and migration, were increased. In contrast, rapamycin decreased p-S6 expression, as well as proliferation and migration, in HG induced HRCECs compared to the control group (p < 0.05).

Conclusion

mTORC1 plays an important role in DR. After activation, mTORC1 induced expression of the p-S6 protein, regulated the expressions of VEGF and PEDF proteins, and changed the proliferation and migration of endothelial cells. The mTORC1 can therefore be used as a new target,as well as in the treatment of DR.

Toth G, Szabo D, Sandor GL, Pek A, Szalai I, Lukacs R, Toth GZ, Papp A, Nagy ZZ, Limburg H, Nemeth J. Orv Hetil. Regional disparities in the prevalence of diabetes and diabetic retinopathy in Hungary in people aged 50 years and older. Orv Hetil. 2017;158(10):362–7.

Schmidt-Erfurth U, Garcia-Arumi J, Bandello F, Berg K, Chakravarthy U, Gerendas BS, Jonas J, Larsen M, Tadayoni R, Loewenstein A. Guidelines for the Management of Diabetic Macular Edema by the European Society of Retina Specialists (EURETINA). Ophthalmologica. 2017;237(4):185–222.

Li YY, Yang XF, Gu H, Snellingen T, Liu XP, Liu NP. The relationship between insulin resistance/β-cell dysfunction and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus: the Desheng Diabetic Eye Study. Int J Ophthalmol. 2018;11(3):493–500.

Shi H, Zhang Z, Wang X, Li R, Hou W, Bi W, Zhang X. Inhibition of autophagy induces IL-1β release from ARPE-19 cells via ROS mediated NLRP3 inflammasome activation under high glucose stress. Biochem Biophys Res Commun. 2015;463(4):1071–6.

Behl T, Kaur I, Kotwani A. Implication of oxidative stress in progression of diabetic retinopathy. Surv Ophthalmol. 2016;61(2):187–96.

Rosa MD, Distefano G, Gagliano C, Rusciano D, Malaguarnera L. Autophagy in diabetic retinopathy. Curr Neuropharmacol. 2016;14(8):810–25.

Ola MS, Nawaz MI, Siddiquei MM, Al-Amro S, Abu El-Asrar AM. Recent advances in understanding the biochemical and molecular mechanism of diabetic retinopathy. J Diabetes Complications. 2012;26(1):56–64.

Portillo JC, Lopez Corcino Y, Miao Y, Tang J, Sheibani N, Kern TS, Dubyak GR, Subauste CS. CD40 in retinal müller cells induces P2X7-dependent cytokine expression in macrophages/microglia in diabetic mice and development of early experimental diabetic retinopathy. Diabetes. 2017;66(2):483–93.

Ben-Sahra I, Manning BD. mTORC1 signaling and the metabolic control of cell growth. Curr Opin Cell Biol. 2017;45:72–82.

10.

Calton MA, Vollrath D. The mTOR kinase inhibitor INK128 blunts migration of cultured retinal pigment epithelial cells. Adv Exp Med Biol. 2016;854:709–15.

11.

Fort PE, Losiewicz MK, Pennathur S, Jefferson LS, Kimball SR, Abcouwer SF, Gardner TW. mTORC1-independent reduction of retinal protein synthesis in type 1 diabetes. Diabetes. 2014;63(9):3077–90.

12.

Huang C, Zhu HJ, Li H, Li QX, Li FM, Cheng L, Liu YG. p38-MAPK pathway is activated in retinopathy of microvascular disease of STZ-induced diabetic rat model. Eur Rev Med Pharmacol Sci. 2018;22(18):5789–96.

13.

Zhuang P, Muraleedharan CK, Xu S. Intraocular delivery of miR-146 inhibits diabetes-induced retinal functional defects in diabetic rat model. Invest Ophthalmol Vis Sci. 2017;58(3):1646–55.

14.

Wang T, Xing Y, Meng Q, Lu H, Liu W, Yan S, Song Y, Xu X, Huang J, Cui Y, Jia D, Cai L. Mammalian Eps15 homology domain 1 potentiates angiogenesis of non-small cell lung cancer by regulating β2AR signaling. J Exp Clin Cancer Res. 2019;38(1):174.

15.

Xu S, Tang J, Wang C, Liu J, Fu Y, Luo Y. CXCR7 promotes melanoma tumorigenesis via Src kinase signaling. Cell Death Dis. 2019;10(3):191.

16.

Chang JW, Yeh HS, Park M, Erber L, Sun J, Cheng S, Bui AM, Fahmi NA, Nasti R, Kuang R, Chen Y, Zhang W, Yong J. mTOR-regulated U2af1 tandem exon splicing specifies transcriptome features for translational control. Nucleic Acids Res. 2019;47(19):10373–87.

17.

Asrani K, Murali S, Lam B, Na CH, Phatak P, Sood A, Kaur H, Khan Z, Noë M, Anchoori RK, Talbot CC Jr, Smith B, Skaro M, Lotan TL. mTORC1 feedback to AKT modulates lysosomal biogenesis through MiT/TFE regulation. J Clin Invest. 2019;129(12):5584–99.

18.

Chou JC, Rollins SD, Fawzi AA. Trypsin digest protocol to analyze the retinal vasculature of a mouse model. J Vis Exp. 2013;(76):e50489.

19.

Stewart EA, Wei R, Branch MJ, Sidney LE, Amoaku WM. Expression of Toll-like receptors in human retinal and choroidal vascular endothelial cells. Exp Eye Res. 2015;138:114–23.

20.

de Melo AC, Paulino E, Garces ÁH. A Review of mTOR Pathway Inhibitors in Gynecologic Cancer. Oxid Med Cell Longev. 2017;2017:4809751.

21.

Heitman J, Movva NR, Hall MN. Targets for cell cycle arrest by the immunosuppressant rapamycin in yeast. Science. 1991;253(5022):905–9.

22.

Zoncu R, Efeyan A, Sabatini DM. mTOR: from growth signal integration to cancer, diabetes and ageing. Nat Rev Mol Cell Biol. 2011;12(1):21–35.

23.

Kennedy BK, Lamming DW. The mechanistic target of rapamycin: the grand ConducTOR of metabolism and aging. Cell Metab. 2016;23(6):990–1003.

24.

Lu Q, Wang WW, Zhang MZ, Ma ZX, Qiu XR, Shen M, Yin XX. ROS induces epithelial-mesenchymal transition via the TGF-β1/PI3K/Akt/mTOR pathway in diabetic nephropathy. Exp Ther Med. 2019;17(1):835–46.

25.

Zhu L, Hao J, Cheng M, Zhang C, Huo C, Liu Y, Du W, Zhang X. Hyperglycemia-induced Bcl-2/Bax-mediated apoptosis of Schwann cells via mTORC1/S6K1 inhibition in diabetic peripheral neuropathy. Exp Cell Res. 2018;367(2):186–95.

26.

Zhang J, Jiang H, Liu DH, Wang GN. Effects of dexmedetomidine on myocardial ischemia-reperfusion injury through PI3K-Akt-mTOR signaling pathway. Eur Rev Med Pharmacol Sci. 2019;23:6736–43.

27.

Yang H, Jiang X, Li B, Yang HJ, Miller M, Yang A, Dhar A, Pavletich NP. Mechanisms of mTORC1 activation by RHEB and inhibition by PRAS40. Nature. 2017;552(7685):368–73.

28.

Docquier A, Pavlin L, Raibon A, Bertrand-Gaday C, Sar C, Leibovitch S, Candau R, Bernardi H. eIF3f depletion impedes mouse embryonic development, reduces adult skeletal muscle mass and amplifies muscle loss during disuse. J Physiol. 2019;597(12):3107–31.

29.

Liu D, Bordicchia M, Zhang C, Fang H, Wei W, Li JL, Guilherme A, Guntur K, Czech MP, Collins S. Activation of mTORC1 is essential for β-adrenergic stimulation of adipose browning. J Clin Invest. 2016;126:1704–16.

30.

Lu T, Zhu Z, Wu J, She H, Han R, Xu H, Qin ZH. DRAM1 regulates autophagy and cell proliferation via inhibition of the phosphoinositide 3-kinase-Akt-mTOR-ribosomal protein S6 pathway. Cell Commun Signal. 2019;17(1):28.

Title: The expression and significance of mTORC1 in diabetic retinopathy
Authors: Yanli Liu
Yarong Zheng
Yekai Zhou
Yi Liu
Mengxuan Xie
Wenjing Meng
Meixia An
Publication date: 01-12-2020
Publisher: BioMed Central
Keywords: Diabetic Retinopathy
Diabetic Retinopathy
Diabetes
Published in: BMC Ophthalmology / Issue 1/2020
Electronic ISSN: 1471-2415
DOI: https://doi.org/10.1186/s12886-020-01553-3

Keynote webinar | Spotlight on medication adherence

Springer Medicine

The expression and significance of mTORC1 in diabetic retinopathy

Abstract

Background

Methods

Results

Conclusion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods

Results

Conclusion

Please log in to get access to this content

Other articles of this Issue 1/2020

Cataract and glaucoma combined surgery: XEN® gel stent versus nonpenetrating deep sclerectomy, a pilot study

Efficacy of intravitreal Lucentis injection on major and macular branch retinal vein occlusion

Targeted exome sequencing identified a novel USH2A mutation in a Chinese usher syndrome family: a case report

Lens-induced myopization and intraocular pressure in young guinea pigs

Toric intraocular lens implantation in cataract patients with corneal opacity

Ophthalmic manifestations of congenital protein C deficiency: a case report and mini review