Study: Investigators make key discovery in AMD

Inflammation and its processes can spark the progression of age-related macular degeneration (AMD) disease—a leading cause of vision loss in the United States.

In a study,¹ a team of investigators from the University of California Irvine and University of Southern California looked at the protein levels of inflammation markers in normal and AMD retinal pigment epithelial (RPE) transmitochondrial cybrid cells and investigated the effects of treatment with exogenous Humanin G.

According to the study, Humanin G (HNG) is a mitochondrial derived peptide that is cytoprotective in AMD and can protect against mitochondrial and cellular stress induced by damaged AMD mitochondria.

“The goal of this study was to test our hypothesis that inflammation-associated marker protein levels are increased in AMD and treatment with HNG leads to reduction in their protein levels,” the investigators wrote in a news release.

The investigators noted that the Humanin G protein levels were measured in the plasma of AMD patients and normal subjects using ELISA assay. The study also noted that Humanin G was introduced to AMD and normal (control) cybrids derived from clinically characterized AMD patients and normal (control) subjects.

The investigators noted that cell lysates were extracted from untreated and HNG-treated AMD and normal cybrids, and the Luminex XMAP multiplex assay was used to measure the levels of inflammatory proteins.

According to investigators, there were differential levels of inflammation proteins between normal and AMD plasma samples. The team pointed out that when compared to control plasma samples, AMD plasma showed higher protein levels of inflammation markers.

“In conclusion, we present novel findings that: a) show reduced Humanin protein levels in AMD plasma vs. normal plasma; b) suggest the role of inflammatory markers in AMD pathogenesis, and c) highlight the positive effects of Humanin G in reducing inflammation in AMD,” investigators wrote in the news release.

Investigators noted that as best as they can ascertain, this is the first study to report notably reduced Humanin protein levels in AMD patients, which would corroborate the pivotal role of Humanin in maintaining tissue homeostasis and normal functioning in the eye.

“Our discovery is novel and may contribute to the development of therapeutics tools for reducing inflammation to alleviate AMD disease pathology,” investigators concluded.

Reference

1 Sonali Nashine, et al. Effect of Human G (HNG) on inflammation in age-related macular degeneration (AMD). Aging. Published May 16 ,2022. doi: 10.18632.aging.204074