Journal of Molecular Neuroscience

, Volume 61, Issue 4, pp 581–589 | Cite as

Crocin Inhibits Oxidative Stress and Pro-inflammatory Response of Microglial Cells Associated with Diabetic Retinopathy Through the Activation of PI3K/Akt Signaling Pathway

  • Xinguang Yang
  • Fuquan Huo
  • Bei Liu
  • Jing Liu
  • Tao Chen
  • Junping Li
  • Zhongqiao ZhuEmail author
  • Bochang LvEmail author


Diabetic retinopathy (DR) is a serious microvascular complication of diabetes mellitus that is closely associated with the degeneration and loss of retinal ganglion cells (RGCs) caused by diabetic microangiopathy and subsequent oxidative stress and an inflammatory response. Microglial cells are classed as neurogliocytes and play a significant role in neurodegenerative diseases. Over-activated microglial cells may cause neurotoxicity and induce the death and apoptosis of RGCs. Crocin is one of the two most pharmacologically bioactive constituents in saffron. In the present study, we focused on the role of microglial cells in DR, suggesting that DR may cause the over-activation of microglial cells and induce oxidative stress and the release of pro-inflammatory factors. Microglial cells BV-2 and N9 were cultured, and high-glucose (HG) and free fatty acid (FFA) were used to simulate diabetes. The results showed that HG-FFA co-treatment caused the up-regulated expression of CD11b and Iba-1, indicating that BV-2 and N9 cells were over-activated. Moreover, oxidative stress markers and pro-inflammatory factors were significantly enhanced by HG-FFA treatment. We found that crocin prevented the oxidative stress and pro-inflammatory response induced by HG-FFA co-treatment. Moreover, using the PI3K/Akt inhibitor LY294002, we revealed that PI3K/Akt signaling plays a significant role in blocking oxidative stress, suppressing the pro-inflammatory response, and maintaining the neuroprotective effects of crocin. In total, these results provide a new insight into DR and DR-induced oxidative stress and the inflammatory response, which provide a potential therapeutic target for neuronal damage, vision loss, and other DR-induced complications.


Crocin Microglial cells Diabetic retinopathy PI3K/Akt 



This study was supported by the National Natural Science Foundation of China (No. 81273902).

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.Shaanxi Ophthalmic Medical Center, Xi’an No. 4 HospitalGuangren Hospital Affiliated to School of Medicine of Xi’an Jiaotong UniversityXi’anPeople’s Republic of China
  2. 2.Department of Physiology and Pathophysiology, Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education, School of MedicineXi’an Jiaotong UniversityXi’anChina
  3. 3.Department of Anatomy, Histology and Embryology and K. K. Leung Brain Research CentreThe Fourth Military Medical UniversityXi’anPeople’s Republic of China
  4. 4.Department of Anatomy, Histology and EmbryologyNingxia Medical UniversityYinchuanPeople’s Republic of China

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