It’s a critical tradeoff for life. Our bodies use sugar and fat from the food we consume to produce energy in our cells’ mitochondria, the internal powerhouses that give us the energy we need for all our vital functions.
Over time—a lifetime—this conversion of fuel to energy causes mitochondria to accumulate free radical damage associated with the reactive oxygen species (ROS) mitochondria generate. The concept of free radicals as the enemy of time was first proposed in the 1950s as a new theory on aging, and by the 1970s included mitochondrial ROS (mtROS) as the major source of radical damage.
“It’s similar to how a car produces an exhaust after it has used gasoline for power,” said Dr. Christopher Perry, an assistant professor at York University in Toronto who studies mitochondria. “In small amounts, reactive oxygen species are not toxic, but they can damage cells and contribute to many diseases if mitochondria produce too many of these chemicals.”
Since the introduction of the concept of free radical damage, there has been a plethora of scientific experiments and studies that point a finger at oxidative stress inside mitochondria as a factor in a number of disorders afflicting aging populations. This can include cardiovascular disorders, arthritis, diabetes, and neurodegenerative disease like Parkinson’s, Multiple Sclerosis and rare diseases like Barth Syndrome.
Although there are molecules that can neutralize the ROS, protecting our mitochondria from damage by oxidative stress has traditionally been problematic because these molecules distribute throughout the body but don’t reach effective levels in the mitochondria. However, a few years ago, researchers at Moscow State University developed a small molecule dubbed SkQ1 that has split duties. One part of the molecule acts as a very efficient and targeted carrier into mitochondria for another part of the molecule that is an active antioxidant plastoquinone.
The discovery turned into Mitotech, a company based in Luxembourg that is focused on developing SkQ1 for the treatment of numerous age-related disorders. While SkQ1 is an antioxidant that protects the body from an excess of ROS, it differs from more common antioxidants like vitamin C or vitamin E.
“SkQ1’s uniqueness and innovation is that it was designed to accumulate inside an important part of every living cell,” said Lawrence Friedhoff, M.D., Mitotech’s chief clinical officer. “And that’s what makes the difference—targeting free radicals where they do most of their damage to the cell, inside mitochondria.”
SkQ1’s ability to block the consequences of excessive oxidative stress in mitochondria can potentially lead to disease modifying effects in patients suffering from such disorders as liver and heart diseases, and neurodegenerative diseases.
In the near term, Mitotech is using SkQ1 in its pipeline product, Visomitin eye drops, for the treatment of Dry Eye Disease. Visomitin is approved in Russia and had a successful Phase II study in the U.S. that indicated a statistically significant effect of SkQ1 on both signs and symptoms of Dry Eye Disease. Preparations are currently underway for Visomitin’s Phase III trials, with hopes of getting it before the FDA by 2019.
The company has also completed pre-clinical trials in the U.S. for Plastomitin, a pill based on SkQ1 for the treatment of Multiple Sclerosis, Acute Kidney Injury and Barth Syndrome, which is a genetic disorder that affects multiple body systems. Phase I studies in Russia for Plastomitin for treating neurodegeneration are currently in progress.
In a recently published study conducted at Stockholm University in collaboration with Moscow State University, SkQ1 was found to increase longevity of mtDNA mutator mice that are known to age prematurely. The mice treated with SkQ1 showed normalized mitochondrial ultrastructure of liver and heart and lower levels of kyphosis and hypothermia compared to the untreated group.
“If, indeed, aging results from decreased mitochondrial health, and not just correlates with this… then SkQ1 would improve our health during aging,” said Dr. Barbara Cannon, a professor in physiology at Stockholm University and a co-lead of the study.
“Mitotech has conducted a large number of animal and human studies and found SkQ1 has not demonstrated any negative effect within the chosen therapeutic dose range,” Friedhoff said.
Some of those experiments evaluated the effect of chronic administration of SkQ1 for long periods of time, as in the case of animal longevity experiments. In these experiments, SkQ1 was administered for a significant part of the animal's lifetime and showed significant benefits without notable negative effects. “It is really difficult to overestimate the impact SkQ1 can make if it proves successful,” Friedhoff said.