Complex sentence: This experiment was performed by knockout (KO) of the Cry circadian genes in mice set off a molecular signal transduction pathway making use of secondary messenger cAMP that resulted in highly elevated levels of cytokines that trigger inflammatory immune responses.
Split into simpler sentences: This experiment was performed by knockout (KO) of the Cry circadian genes in mice which set off a molecular signal transduction pathway that used secondary messenger cAMP. The result was highly elevated levels of cytokines that trigger inflammatory immune responses.