Nicotinic Induction of Preproenkephalin and Tyrosine Hydroxylase Gene Expression in Butyrate-Differentiated Rat PC12 Cells: A Model for Adaptation to Gut-Derived Environmental Signals

Abstract

Accelerated maturation of peripheral sympathoadrenal transmitter levels and function occurs at 7-10 postnatal days in the rat. This event is temporally disconnected from the timing of major changes in physiologic stimuli evident after the birthing process (i.e. temperature, oxygen, sound, light, etc.). Colonization of the gut, fermentation of carbohydrates, and production of short-chain fatty acids (e.g. butyrate) mirrors this postnatal time course. In this report, we examined the interaction between butyrate differentiation of rat pheochromocytoma cells and cholinergicnicotinic induction of the neuropeptide (enkephalin) and catecholamine-related biosynthetic enzymes (tyrosine hydroxylase, dopamine ␤-hydroxylase, phenylethanolamine N-methyltransferase). Our results show that butyrate induces both preproenkephalin and tyrosine hydroxylase mRNA through a proximal promoter region and that this regulatory step is time and dose dependent. Moreover, there is an additional interaction with cholinergic-nicotinic inducible mechanisms consistent with classically described transsynaptic cholinergic regulation of these genes. Dopamine ␤-hydroxylase and phenylethanolamine Nmethyltransferase promoters were not affected by butyrate treatment. We speculate that colonization of the human gut (along with the attendant fermentation of enteral carbohydrates to shortchain fatty acids) may represent a mechanism through which environmental signals affect postnatal maturation of sympathoadrenal transmitter systems. Abbreviations ppENK, preproenkephalin pRPE2, enkephalin gene coding sequence plasmid pREJCAT, enkephalin promoter reporter plasmid TH, tyrosine hydroxylase DBH, dopamine ␤-hydroxylase PNMT, phenylethanolamine N-methyltransferase CAT, chloramphenicol acetyltransferase PC12, rat pheochromocytoma SCFA, short-chain fatty acids NaBtr, sodium butyrate Circulating catecholamines and endogenous opioid peptides arise primarily from the adrenal medulla (1, 2), where they are co-stored and co-released from chromaffin cells (3). In rats, between 7 and 10 days of postnatal life, adrenal transmitter biosynthetic and release mechanisms mature to adult capacity in response to progressive cholinergic innervation, and as a result of the influences of the hypothalamic-pituitary-adrenal cortical and thyroid hormonal systems (4 -13). Because a progressive rise in systemic blood pressure and autonomic reflex responsiveness is well characterized in the first postnatal week in humans (11), similar control mechanisms are thought to apply. Paradoxically, it is well recognized that adrenal transmitter systems can adapt rapidly to change steady-state levels of transmitter-related mRNA in as little as a few hours, not typically a few days (14 -17

Intrathecal Implantation of Microencapsulated PC12 Cells Reduces Cold Allodynia in a Rat Model of Neuropathic Pain

“…The PC12 cells were grown in Dulbecco's Modified Eagle Medium (High Glucose, Gibco, Grand Island, NY, USA) supplemented with 5% perinatal calf serum (HyClone, Logan, UT, USA), 10% horse serum (Gibco), 50 U/mL penicillin, and 50 ug/mL streptomycin, as previously reported (13).…”

Chemogenomic analysis of neuronal differentiation with pathway changes in PC12 cells

“…protection mechanisms, and neuroendocrinology. [12][13][14][15][16][17] Early studies with this cell line showed that NGF treatment induces neuronal differentiation. 18 Under NGF stimulation, PC12 cells will slow down cell divisions and differentiation into sympathetic neuron-like cells with neurite outgrowth.…”

Microarray and Synchronization of Neuronal Differentiation with Pathway Changes in the Kyoto Encyclopedia of Genes and Genomes (KEGG) Databank in Nerve Growth Factor-Treated PC12 Cells

“…PC12 cells have been widely used as a model for the study nerve differentiation, neurotoxicity, neuropharmacology, neuronal protection mechanisms, and neuroendocrinology [11][12][13][14][15][16]. Early studies with this cell line showed that NGF treatment induces neuronal differentiation [17].…”