Is Zinc Beneficial or Harmful in Kidney Stone?

Impact of zinc on inhibition or promotion of kidney stones gives rise to two conflicting theories, as per a study at the University of Houston, reported in the America Chemical Society journal Crystal Growth & Design. The two contradicting results of zinc observed were reported. "What we see with zinc is something we haven't seen before. It does slow down calcium oxalate crystal growth and at the same time, it changes the surface of the crystals, causing defects in the form of intergrowths. These abnormalities create centers for new crystals to nucleate and grow," says Jeffrey Rimer, Professor of Chemical and Biomolecular Engineering at the University of Houston, who refers to the effect as a double-edged sword.

Kidney stone formation is a pathological condition that has increased in frequency among patients, causing an increased amount of suffering and a steep rise in medical costs.

Role of Zinc on Kidney Stones

The most naturally abundant form of crystals found in human kidney stone disease is calcium oxalate monohydrates (COM) along with hard deposits of various inorganic salts and organic compounds (e.g., proteins) in concentrated urine. They can produce severe pain when passed through the urinary tract.

The effects of zinc on COM crystal growth were decoded by the study team using a combination of in vitro experiments and computational modeling. This may aid in understanding the kidney stone formation at a molecular level and the impact of various species in urine for crystal growth regulation.

The team confirmed the dual role of zinc on COM by atomic force microscopy measurements that revealed a unique ability of zinc ions to alter the termination of crystal surfaces.

"We wondered what would happen if we used alternative ions commonly found in urine, such as magnesium, and the answer was nothing. It had little to no effect, whereas zinc had a major effect. This is an excellent demonstration of how subtle differences in the nature of various species impact their interaction with crystal surfaces," says Rimer.

Source-Medindia