AAT Bioquest

Acetylcholinesterase Inhibitory Activity of Pigment Echinochrome A

Finding a cure for Alzheimer's Disease (AD) is one of the great challenges of today's medical community. With its devastating effects for millions of patients worldwide, finding an effective cure is a challenge that needs to be overcome in order to aid in the continued improvement of human health. Finding an effective solution, though, requires first understanding the underlying causes that can be targeted by therapeutic drugs. AD's development has been linked to β-amyloid deposition, oxidative stress, and inflammation, and so developing drugs that target these pathological events is essential. Lee et al. from the National Research Laboratory for Mitochondrial Signaling at Inje University in South Korea decided to tackle this problem by looking at the interaction of Acetylcholinesterase(AChE), a serine hydrolase belonging to the carboxylesterase family of enzymes, and Acetylcholine, a neurotransmitter in the central nervous system that is hydrolyzed by AChE into choline and acetic acid. An increased supply of AChE leads to a decreased level of ACh, which, along with the loss of cholinergic neurons, is part of the pathogenesis of AD. Finding an effective AChE inhibitor is key to finding an effective treatment for AD.

Currently, there are only three known AChE inhibitors, and they can be found naturally or chemically synthesized. Lee and his colleagues wanted to look at the effectiveness of Echinochrome A (EchA) as an AChE inhibitor, largely because EchA has been found to be effective as a treatment for several other conditions. For example, it has a cardioprotective capacity, inhibits dopamine-beta-hydroxylase, and can also eliminate retinal inflammation, making it useful for ophthalmology. To study EchA, Lee and his colleagues used the Amplite® Colorimetric Acetylcholinesterase Assay Kit. This kit is a convenient way to quantify AChE activity by using DTNB to measure the thiocholine produced in the hydrolysis of acetylthiocholine by AChE on red blood cell membranes, in cell extracts, and other solutions. What makes this tool so effective is its ability to detect minute amounts of AChE; the colorimetric one-step assay makes it possible to detect as little as .1 mU AChE in a 100 µL assay volume, which helps provide more robust and accurate results. This allows researchers to see with great precision the effect of EchA on AChE.

What Lee and his team of researchers found was that EchA is, in fact, a significant AChE inhibitor. This indicates that it does have promise as a potential therapy for AD, since it can help to keep levels of ACh high by preventing its hydrolysis. This stands to have profound implications as it opens another door for the development of AD therapies, bringing the medical community one step closer to a cure. However, it is important to point out the importance of being able to accurately measure AChE levels. By using a reliable and accurate tool such as the Amplite® Colorimetric Acetylcholinesterase Assay Kit, researchers were able to confidently measure their results, which helps contribute to the reliability of the study and makes its implications more credible. Obtaining quality, sound results in studies like these is critical for the advance to a cure.



  1. Lee, Sung Ryul, et al. "Acetylcholinesterase inhibitory activity of pigment echinochrome A from sea urchin Scaphechinus mirabilis." Marine drugs 12.6 (2014): 3560-3573.

Original created on April 18, 2017, last updated on April 18, 2017
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