CLINICAL CASE 40: ANSWERS AND SUMMARY

Besides phosphate metabolism, what other functions does the klotho gene have associations with?

insulin resistance	5 (11%)
thyroid disease	0 (0%)
aging	35 (81%)
development of the hypothalamus	0 (0%)
sensory neuron development	3 (6%)

Interesting history regarding Klotho. The gene actually was first identified as a aging suppressor gene that extended life span before it got its glory in FGF 23 and phosphate regulation. So Aging is the right answer.  Klotho is also an obligate co receptor to FGF 23( which suppresses phosphate reabsorption and 1,25 Vit D synthesis in the kidney).

Klotho actually means "who spun the thread of life".  The klotho knockout mouse has the following finding:

faster aging, hypogonadism, growth retardation, atrophy of skin, cognition impairment.

The transgenic Klotho mice have increase in lifespan. FGF 23 def mice are similar to Klotho def mice and hence the relation came about.  Some studies show that it is the phosphate retention that causes extensive aging like features. It is not surprising that it is the phosphate that really makes the big difference in CKD and dialysis patients.  

Interesting concepts

Check out ref:

http://www.ncbi.nlm.nih.gov/pubmed/19329831

http://www.ncbi.nlm.nih.gov/pubmed/21164022

http://www.ncbi.nlm.nih.gov/pubmed/21496980