A researcher at Massachusetts General Hospital (MGH) has identified a previously unknown kidney mechanism vital in blood calcium and magnesium levels regulation. The researcher discovered while studying the underlying cause of rare skin disease.

Research on KCTD1’s role in calcium and magnesium reabsorption

The findings of the discovery described in the Cell Reports journal demonstrate the roles of the previously understudied gene called KCTD1. This gene is vital in directing protein production, critical in regulating the kidney’s ability to reabsorb calcium and magnesium from urine and take it back into the bloodstream. Alexander Marneros, an investigator at the Cutaneous Biology Research Centre at MGH, said that gene mutation that causes KCTD1 loss leads to defects in nephrons which are the kidney’s basic filtration units. He said that KCTD1 is important in nephron segments involved in magnesium, calcium, and salt regulation from filtered urine back to the bloodstream.

Usually, the nephron defects resulting due to KCTD1 loss cause abnormally low calcium (hypocalcemia) and magnesium (hypomagnesemia) levels in the bloodstream. As a result, the abnormally low calcium levels in the blood triggers parathyroid hormone-secreting glands in the neck to overwork leading to a condition called secondary hyperparathyroidism. Subsequently, the high parathyroid hormone levels result in calcium release from bones to balance calcium levels in the blood, thus leading to bone mass loss.

KCTD1 deficiency causes kidney abnormalities

Marneros highlighted the initial kidney abnormalities identification due to KCTD1 deficiency in a study published in the Development Cell journal last year. The study showed that KCTD1 deficiency in mutant mice resulted in progressive kidney abnormalities resembling chronic kidney disease findings. He observed that KCTD1 mutation patients also had CKD with renal fibrosis, with findings showing KCTD1’s importance.

In the present study, he points KCTD1 acts in part on the distal nephron in regulating electrolytes reabsorption from urine into the bloodstream and maintaining balance levels of the electrolytes. Morneros said that the distal nephron’s function includes calcium and magnesium reabsorption and KCTD1 is important for that ability.