Histochemical demonstration of a circadian rhythm of succinate dehydrogenase in rat pineal gland. Influence of coenzyme Q10 addition

Abstract

Succinate dehydrogenase activity was investigated histochemically in the rat pineal gland. The influence of fixation on the activity pattern, the possible diffusion of enzyme, the nothing dehydrogenase reaction, and the substantivity of the tetrazolium salts and formazans were investigated in control experiments. In rats maintained on a 17/7 h light/dark schedule a distinct circadian rhythm of the succinate dehydrogenase was demonstrated in the pineal gland. Activity was lowest during the day and highest during the night. The dorsocaudal part of the gland showed the highest activity and within the same part of the gland the activity varied between individual pinealocytes. A relative lack of endogenous coenzyme Q, as well as a circadian rhythm of this coenzyme, highly influenced the activity of succinate dehydrogenase. It is concluded that succinate dehydrogenase activity in the pineal gland of the rat is regulated by changing the concentration of the active enzyme itself as well as the level of the endogenous coenzyme Q. Whether this is caused by a circadian rhythm in the synthesis or in the catabolism of the enzyme and the coenzyme was not revealed by the present study .

Proteomic analysis of day–night variations in protein levels in the rat pineal gland

“…Quantitative enzyme histochemistry has also shown an up-regulation of the Krebs cycle during nighttime. Thus, a nighttime increase in succinic dehydrogenase activity is shown in Wistar rats [41]. Some enzymes, such as creatine kinase, which was found up-regulated at night, are involved in energy transduction.…”

Mass‐spectrometry analysis of the human pineal proteome during night and day and in autism

“…71 In this line, previous studies indicate a higher level of mitochondrial respiratory chain enzymes during the night. 72 However we also identified several glycolytic enzymes which are upregulated during daytime including PFKM, GAPDH and HK1 indicating that they may influence several metabolic activities in the pineal gland in daytime. Altogether, these results suggest that energy production within the pineal gland is fine-tuned during night and day.…”

“…LDH is the terminal enzyme of anaerobic glycolysis and involved in recycling of NADH to NAD + , 69 6PGD is involved in the pentose phosphate pathway generating NADPH whose function is critical to maintain redox balance under stress situations, 70 and ATP5O a subunit of mitochondrial ATP synthase involved in ATP production within the mitochondrial respiratory chain 71 . In this line, previous studies indicate a higher level of mitochondrial respiratory chain enzymes during the night 72 . However we also identified several glycolytic enzymes which are upregulated during daytime including PFKM, GAPDH and HK1 indicating that they may influence several metabolic activities in the pineal gland in daytime.…”

Cerebrospinal Fluid (CSF) Concentration of Coenzyme Q10 in Clinical Practice, A Breaking News Finding in Humans

“…A rarer myopathic varient combines central nervous system signs; ataxia,epilepsy,and mental retardation,with a mitochondrial myopathy dominated by recurrent rhabdomyolysis and myoglobinuria which are also an adverse effect of statin. A circadian rhythm in the coenzyme concentrations and a histochemical demonstration of a circadian rhythm of succinate dehydrogenase in rat pineal gland, and influence of CoQ 10 addition has also been observed [16].…”