Saffron (Crocin) (2016) & Retinal Nerve Cells


Learn more about glaucoma.


A hallmark of glaucoma is the cell death of nerve cells in the retina (retinal ganglion cells). Their death is caused by any number of factors; one of which is oxidative stress. The carotenoids are known to reduce oxidative stress, and crocin in particular appears to be effective with respect to retinal nerve cell health. Crocin comes from the spice saffron.

The mechanics of how and why the protective effect occurs however, is not clear and researchers wanted to figure out the process.

The study focused on particular nerve cells called "RGC-5 cells" and treated them with hydrogen peroxide which, in test conditions, mimics oxidative stress and thus mimics the development of glaucoma. The researchers added crocin in various concentrations to test whether it was capable of protecting the RGC-5 cells from damage from the hydrogen peroxide. The researchers analyzed the results from several different angles: looking at levels of free radicals, looking at health of the mitochondria and various proteins and other cell components.

They found that crocin did protect the cells from cell death, slowed the release of the enzyme (LDH), and supported cell health. LDH is released by the body when damage to tissue results for that reason is a biomarker (indicator) of tissue damage.

The researchers also determined that crocin activated NF-kB (nuclear factor kappa-light-chain-enhancer of activated B cells). KF-kB is a complex protein that controls how the cell reacts to stress, the nature of the cellular immune response, etc. In other words balanced and correct regulation of KF-kB in nerve cells determines how well the cell will survive hostile conditions.

Researchers: B. Lv, T. Chen, et al,
Published: Crocin protects retinal ganglion cells against H2O2-induced damage through the mitochondrial pathway and activation of NF-κB, International Journal of Molecular Medicine, January, 2016.

Another study looked at a process called microglial activation with respect to how crocin protects retinal nerve (ganglion) cells.

Microglial activation is the cells inflammatory immune response to damage such as oxidative damage. Researchers found that through a complex process crocin successfully inhibiting the signaling that usually triggers inflammation which in turn can damage the retinal nerve cells.

The researchers point out that glaucoma is a group of neurodegenerative eye diseases which are marked by loss of retinal nerve cells and conclude that crocin successfully and effectively protects the nerve cells.

Researchers: B. Lv, F. Huo, et al,
Published: Crocin Upregulates CX3CR1 Expression by Suppressing NF-κB/YY1 Signaling and Inhibiting Lipopolysaccharide-Induced Microglial Activation, Neurochemical Research, August, 2016.