Chronic kidney disease, or CKD, affects millions of people worldwide. As the disease gets worse, many patients need dialysis to stay alive. Today, no medicine can actually restore kidney function.
Scientists at Tohoku University discovered that a drug used for constipation might help. In a clinical trial, the medicine called lubiprostone slowed the loss of kidney function in patients with moderate CKD.
"We often see constipation in people with kidney disease," said researcher Abe. "We thought that fixing constipation could also help the kidneys because the gut and kidneys are linked."
The Gut‑Kidney Connection
Doctors are learning that the gut and kidneys talk to each other. Bad gut bacteria can cause inflammation and harmful chemicals that hurt the kidneys. People with CKD often have constipation and an unhealthy gut.
To test this idea, researchers ran a Phase II trial called LUBI‑CKD across nine hospitals in Japan. One hundred fifty participants with moderate CKD received either lubiprostone or a placebo.
The results were surprising. Those who took 8 µg or 16 µg of lubiprostone had a slower drop in their estimated glomerular filtration rate (eGFR), a key measure of kidney health, compared with the placebo group.
The benefit grew with a higher dose. The 16 µg group showed the most noticeable protection over the 24‑week study.
How the Pill Might Protect Kidneys
Further analysis pointed to changes in the gut microbiome. Lubiprostone increased a natural compound called spermidine, which supports healthy mitochondria—the cell’s power plants.
Better mitochondrial function may shield kidney cells from damage. The researchers also saw shifts in bacterial pathways that produce polyamines, adding more proof that gut microbes can affect kidney health.
Interestingly, the drug did not lower several toxic substances that were expected to change. Instead, the kidney benefit seemed tied to a healthier gut and stronger mitochondria.
Why This Matters
Lubiprostone is already approved for chronic constipation, so using it for kidney disease could move faster than creating a brand‑new drug.
The findings may reach beyond kidneys. Since many chronic illnesses involve faulty mitochondria, fixing the gut might help other diseases too.
The team plans larger Phase III trials to see if the results hold for more patients. They are also looking for markers that predict who will respond best.
Even a small slowdown in kidney decline can delay the need for dialysis and improve quality of life for people living with CKD.