Citrate Synthase, Buccal

An elevated Citrate Synthase (CS) level in buccal cells indicates increased mitochondrial content. This is often interpreted as a compensatory response, where the body produces more mitochondria to keep up with cellular energy demands or to overcome inefficiencies in the mitochondrial respiratory chain. High CS can be seen in individuals experiencing chronic energy stress, mitochondrial dysfunction, increased metabolic activity, or certain neurodevelopmental conditions. While elevated CS is not harmful by itself, it should be interpreted alongside other mitochondrial enzyme markers (RC-I, RC-II, RC-IV) to understand whether the increase reflects healthy adaptation or compensation for underlying dysfunction.

A low Citrate Synthase (CS) value suggests reduced mitochondrial content in the buccal cells. This may occur when the body is not producing adequate mitochondria (reduced mitochondrial biogenesis) or when mitochondrial density is lower due to metabolic, genetic, or environmental factors. Low CS can be associated with impaired energy production, fatigue, metabolic stress, or conditions involving mitochondrial underperformance. Because buccal mitochondrial testing is a screening tool, a low CS result should be interpreted in combination with other mitochondrial enzyme activities and clinical symptoms.

Citrate Synthase (CS) is an enzyme found inside mitochondria—the structures responsible for producing cellular energy. In buccal (cheek) cells, CS is used as a marker of mitochondrial content. Higher CS activity typically reflects an increased number of mitochondria in the sampled cells, while lower activity suggests reduced mitochondrial density. Because buccal cells can mirror mitochondrial patterns seen in other tissues, this test helps clinicians assess potential mitochondrial stress, dysfunction, or compensatory changes in energy production.