Homocystine is the double-bonded form of homocysteine but it occurs only transiently before being converted to the harmless cystathionine via a vitamin B6-dependent enzyme. Homocystine and homocysteine-cysteine mixed disulfide account for >98% of total homocysteine in plasma from healthy individuals.

Mas17

Leptin (93-105), human, is the amino acids 93 to 105 fragment of human leptin. Leptin is a 167-residue peptide hormone mainly produced by adipocytes and acts in the central nervous system to primarily coordinate the metabolic adaptations to fasting.