Association of insulin resistance with the accumulation of saturated intramyocellular lipid: A comparison with other fat stores.

It has been shown using proton magnetic resonance spectroscopy (H MRS) that, in a group of females, whole-body insulin resistance was more closely related to accumulation of saturated intramyocellular lipid (IMCL) than to IMCL concentration alone. This has not been investigated in males. We investigated whether age- and body mass index-matched healthy males differ from the previously reported females in IMCL composition (measured as CH:CH) and IMCL concentration (measured as CH), and in their associations with insulin resistance.

Accumulation of saturated intramyocellular lipid is associated with insulin resistance.

Intramyocellular lipid (IMCL) accumulation has been linked to both insulin-resistant and insulin-sensitive (athletes) states. Biochemical analysis of intramuscular triglyceride composition is confounded by extramyocellular triglycerides in biopsy samples, and hence the specific composition of IMCLs is unknown in these states. H magnetic resonance spectroscopy (MRS) can be used to overcome this problem.

Resistance to thyroid hormone caused by a mutation in thyroid hormone receptor (TR)α1 and TRα2: clinical, biochemical, and genetic analyses of three related patients.

Background: The thyroid hormone receptor α gene (THRA) transcript is alternatively spliced to generate either thyroid hormone receptor (TR)α1 or a non-hormone-binding variant protein, TRα2, the function of which is unknown. Here, we describe the first patients identified with a mutation in THRA that affects both TRα1 and TRα2, and compare them with patients who have resistance to thyroid hormone owing to a mutation affecting only TRα1, to delineate the relative roles of TRα1 and TRα2.

Methods: We did clinical, biochemical, and genetic analyses of an index case and her two sons.