Every day many people in the world volunteer to lose a kidney. It may be to cure a condition, but more often they give a healthy organ for transplantation to someone with permanent kidney failure. In general, kidney donors who have been carefully screened seem to have little kidney morbidity over the long-term.
What are the consequences of uninephrectomy that may not relate directly to kidney function?
Metabolic Consequences of Experimental Uninephrectomy. D Arsenijevic et al
This group (sponsored by Jean-Pierre Montani) performed uninephrectomy or sham procedure in 6-week-old male rats (so an early teenager in human time, an age where removing a functioning kidney is almost unheard of). They then studied body composition and a number of metabolic markers at 1, 2, and 4 weeks following the procedure.
Body weight remained similar between the groups, but fat mass was reduced in the animals that lost a kidney. In addition, there were alterations in circulating lipolytic cytokines, a sign of systemic inflammation.
Systemic inflammation can be bad for your cardiovascular system.
These findings are intriguing, but there are a lot of unanswered questions. First, a 4-week endpoint in a 10-week-old rat is hardly a long-term study. I want to know how these boys do over at least 6 months. Is this an early change that then resolves with time, or one that becomes more pronounced?
What about female rats? I spent too many years considering sex differences to leave that out. Also, it would be interesting to see if uninephrectomy in adult animals (at least 14 weeks of age) has similar effects. That age would be more analogous to the situation in kidney donors.
Since we do so many kidney donor surgeries, there is excellent opportunity to also measure these parameters in people. Measuring fat mass can be expensive and annoying, but drawing blood for lipolytic cytokines would certainly be feasible. Come on - let's get translational!
This abstract is really a teaser, I hope, designed to make us want more answers. In that case, it worked like a charm!