Statins Force a Muscle Gate Open in the Lab, Raising Questions About Aches

Atorvastatin, a widely used cholesterol drug, can grab a calcium channel in muscle and push it open, University of British Columbia researchers found, a possible root of the aches that make patients quit ^[1][2].

The finding was published in Nature Communications on November 20, 2025 ^[1]. It has grown stronger since. On September 3, 2026, a second paper in the same journal reported that another statin, rosuvastatin, also pushes the channel open ^[3].

The drug that millions stop taking

Statins lower cholesterol and cut the risk of heart attack and stroke. The 2025 paper puts their users at more than 200 million people worldwide ^[1].

The trouble is the muscles. Reported effects run from aches and fatigue to rhabdomyolysis, a severe breakdown of muscle tissue that can lead to kidney failure.

The severe end is rare, arising in 0.1% to 0.5% of users, according to the paper. Estimates for ordinary muscle pain vary and are disputed. Muscle symptoms can lead some patients to stop treatment altogether ^[1][2].

A drug that protects the heart does little good in a pill bottle that has been put back in the cupboard. That is why a mechanism matters. Doctors have long known statins can hurt muscle. What has been missing is a precise account of how.

Three molecules at a gate

The team, led by Steven Molinarolo and Filip Van Petegem at UBC with collaborators at the University of Wisconsin-Madison, looked at a protein called RyR1 ^[1][2]. It is a calcium-release channel found chiefly in skeletal muscle, the muscle you move on purpose. Muscle keeps calcium in an internal store. When the channel opens, calcium flows out and the muscle contracts.

A channel that leaks when it should be shut lets calcium escape from that store, and the authors say that could contribute to muscle damage ^[1].

To see what atorvastatin does to it, the researchers used single-particle cryo-electron microscopy. The method images huge numbers of individual protein particles with electrons, then computes their three-dimensional shape ^[1].

The comparison was stark. In the control dataset, with no drug, every RyR1 particle was closed. In the sample with 10 millimolar atorvastatin, about 64% of the particles were open ^[1]. The experiment ran with calcium and caffeine present ^[1].

The structures also showed how the drug does it. Three atorvastatin molecules sit together at each subunit of the channel when it is open.

The authors describe a sequence. One molecule can bind to the closed channel and prime it. Two more then bind as the gate swings open ^[1]. The paper's title calls them statin triplets ^[1].

The authors concluded that atorvastatin can bind directly to RyR1 and activate it ^[1].

What this does not show

This is a structural result from purified protein in a test tube, not a trial in patients. The study examined atorvastatin, not every statin. It does not show that this channel accounts for any given person's aches, and nobody has yet shown whether RyR1 activation at the drug levels found in a patient's body contributes to symptoms ^[1].

It is also not a safer drug. The authors say their structural comparison could help identify ways to reduce RyR1 binding while preserving the drug's intended action on HMG-CoA reductase, the liver enzyme statins block to lower cholesterol ^[1]. UBC's account likewise describes the prospect of designing drugs with fewer muscle effects ^[2]. That is a design goal, not a candidate.

A second statin joins

The September 2026 paper reported a cryo-EM structure of RyR1 with rosuvastatin, another common statin ^[3].

The picture there is different in detail. The authors found one binding site per subunit, not the triplet seen with atorvastatin.

They still reported that rosuvastatin promoted the open state of the channel. They suggest it could be a lead for developing statins with fewer RyR1 effects ^[3]. This too is structural evidence, with no trial of symptoms and no new treatment behind it.

Two statins, two binding patterns, one outcome. That is the strongest argument that the channel is no coincidence. If different molecules in the same drug class reach the same gate by different routes, the gate is worth studying.

It also hints that the class may not be uniform, and that a statin could in principle be built to keep the cholesterol-lowering action and lose the grip on the channel.

The unanswered questions are the ordinary, slow ones. Do other statins bind RyR1 and activate it in living muscle? Do their binding patterns differ enough to guide design? Can a modified compound lower cholesterol and leave the channel alone?

Answering them means cells, then animals, then people, and evidence that any new compound is actually safer.

For the 200 million people taking statins, nothing changes today. Anyone troubled by muscle symptoms should take it up with their doctor, not stop on their own. What changes is that the question "why does this drug hurt my muscles" now has a picture attached, and a picture is where drug design starts.