Catestatin is a biologically active peptide derived from the proteolytic processing of chromogranin A (CgA), a protein co-stored and co-released with catecholamines from adrenal medullary chromaffin cells and sympathetic nerve terminals. It was first identified in the late 1990s as a potent endogenous inhibitor of catecholamine release, functioning as a physiological brake on the sympathetic nervous system. Its discovery stemmed from research into the functional domains of chromogranin A, revealing its role as a key modulator of cardiovascular homeostasis and autonomic function. The significance of catestatin lies in its dual role as both a regulator of catecholamine secretion and an immunomodulatory peptide, positioning it as a critical link between the autonomic nervous system, cardiovascular physiology, and inflammation. Research into catestatin has provided insights into hypertension, heart failure, and metabolic syndrome, suggesting it may serve as both a biomarker and a potential therapeutic target.
Quick Facts
| Also Known As | CST, Chromogranin A352-372, hCgA352-372, Bovine chromogranin A344-364 |
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| Sequence | SSMKLSFRARAYGFRGPGPQL |
| Molecular Formula | C104H164N32O27S |
| Molecular Weight | 2326.7 Da |
| PubChem CID | 71300629 |
Research Parameters
| Half-Life | Unknown in humans. Estimated to be short (minutes) based on peptide characteristics and rodent pharmacokinetics. |
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| Stability | Lyophilized powder is stable for at least 24 months when stored at -20°C or below, protected from light and moisture. After reconstitution in sterile buffer or saline, it should be aliquoted and stored at -20°C or -80°C to prevent degradation; stability after reconstitution is typically limited to a few weeks with repeated freeze-thaw cycles not recommended. |
| Solubility | Recommended reconstitution in sterile 0.9% saline or phosphate-buffered saline (PBS) at a neutral pH. Bacteriostatic water is also commonly used in research settings. |
| Vial Size | 1 mg |
| Storage (Lyophilized) | -20°C or below, desiccated, protected from light. |
| Storage (Reconstituted) | -20°C or -80°C in single-use aliquots. Avoid repeated freeze-thaw cycles. |
| Typical Research Dose | Not established for humans. Rodent research doses range from 2-10 mcg per gram of body weight. |
| Cycle Parameters | No human cycles exist. In chronic animal studies, daily administration (IP or SC injection) for 1-4 weeks is typical. |
| Amino Acid Count | 21 |
Mechanism of Action
Catestatin exerts its primary effects by acting as a non-competitive antagonist at neuronal nicotinic acetylcholine receptors (nAChRs), particularly the α3β4 subtype, which are responsible for triggering catecholamine release from chromaffin cells and sympathetic neurons. By blocking these receptors, catestatin inhibits the exocytotic release of catecholamines like norepinephrine and epinephrine, thereby reducing sympathetic outflow. Its mechanisms extend beyond simple receptor blockade to include modulation of intracellular signaling and paracrine/autocrine effects.
Nicotinic Receptor Antagonism: Catestatin binds to nicotinic acetylcholine receptors on chromaffin cells and postganglionic sympathetic neurons, inhibiting acetylcholine-induced cation influx and subsequent vesicular catecholamine release. This is its canonical mechanism for sympathoinhibition.
Histamine Release and Vasodilation: Catestatin can induce mast cell degranulation and histamine release, leading to vasodilation and a subsequent drop in blood pressure, contributing to its overall hypotensive effect.
Anti-inflammatory and Immunomodulatory Actions: Catestatin inhibits the production of pro-inflammatory cytokines (e.g., TNF-α, IL-6) from macrophages and monocytes stimulated by lipopolysaccharide. It also exhibits antimicrobial activity against bacteria and fungi by disrupting microbial membranes.
Cardioprotective Pathways: In models of myocardial ischemia/reperfusion, catestatin appears to activate survival pathways, possibly involving PI3K/Akt and RISK pathway signaling, reducing infarct size and apoptosis.
Metabolic Effects: Catestatin influences metabolism by improving insulin sensitivity and reducing hepatic glucose output, though these pathways are less well-characterized and may involve indirect effects from reduced sympathetic tone.
Research Applications
Hypertension and Autonomic Dysfunction: Research indicates catestatin's potent ability to lower blood pressure in various hypertensive animal models by inhibiting catecholamine release and promoting vasodilation. Studies focus on its role as an endogenous counter-regulator of sympathetic overactivity, relevant to conditions like essential hypertension, heart failure, and pheochromocytoma.
Heart Failure and Cardioprotection: Animal studies demonstrate that catestatin administration can reduce infarct size following myocardial ischemia, improve cardiac function in heart failure models, and attenuate adverse cardiac remodeling. Its benefits are attributed to reduced catecholamine toxicity, anti-apoptotic effects, and anti-inflammatory actions within the myocardium.
Metabolic Syndrome and Diabetes: Research explores catestatin's role in glucose metabolism and insulin sensitivity. Lower plasma catestatin levels have been correlated with insulin resistance and obesity in human studies. In animal models, catestatin administration improves glucose tolerance and reduces adiposity, suggesting a link between autonomic regulation and metabolic health.
Sepsis and Inflammation: Due to its immunomodulatory properties, catestatin is investigated in models of systemic inflammation and sepsis. It can attenuate the cytokine storm, improve survival in endotoxemic mice, and enhance bacterial clearance, positioning it as a potential modulator of the cholinergic anti-inflammatory pathway.
Psychiatric and Stress-Related Disorders: Preliminary research examines the peptide's role in stress response, given its origin from chromogranin A, a stress-responsive protein. Altered catestatin levels are reported in conditions like PTSD and depression, suggesting a potential link between autonomic dysregulation and psychiatric pathology.
Safety & Side Effects
The safety profile of catestatin in humans is unknown as it has not been evaluated in clinical trials. In animal studies, administration is generally well-tolerated at research doses. The primary pharmacological effect—reduction in sympathetic tone and blood pressure—could theoretically lead to hypotension, bradycardia, or dizziness if translated to humans. Its histamine-releasing property might cause transient flushing or itching. No long-term toxicity studies are available. Anecdotal reports from human use do not exist in the scientific literature, as it remains a research peptide. Theoretical concerns include potential immune reactions with chronic use or dysregulation of autonomic balance.
Dosage Information
Disclaimer: The following information is derived solely from preclinical animal research and is not intended for human use. No established human dosing protocols exist.
In rodent research models, catestatin is typically administered via intravenous (IV), intraperitoneal (IP), or subcutaneous (SC) injection. Doses in murine studies commonly range from 1 to 10 mcg per gram of body weight (e.g., 2-4 mcg/g for cardiovascular effects). For continuous effects, some protocols use osmotic minipumps for subcutaneous infusion. Frequency is often acute (single bolus) for hemodynamic studies or chronic (daily injections over days to weeks) for metabolic or remodeling studies. Duration in chronic studies varies from 1 to 4 weeks.
References
Mahata, S.K., O'Connor, D.T., Mahata, M., et al. Novel autocrine feedback control of catecholamine release. A discrete chromogranin a fragment is a noncompetitive nicotinic cholinergic antagonist. Journal of Clinical Investigation. 1997.
Kennedy, B.P., Mahata, S.K., O'Connor, D.T., et al. Mechanism of cardiovascular actions of the chromogranin A fragment catestatin in vivo. Peptides. 1998.
Gayen, J.R., Saberi, M., Schenk, S., et al. A novel pathway for insulin sensitivity via chromogranin A-derived peptide catestatin. Diabetes. 2009.
Angelone, T., Mazza, R., Cerra, M.C. Catestatin: a multifunctional peptide from chromogranin A. Regulatory Peptides. 2010.
Briolat, J., Wu, S.D., Mahata, S.K., et al. New antimicrobial activity for the catecholamine release-inhibitory peptide from chromogranin A. Cellular and Molecular Life Sciences. 2005.
Penna, C., Alloatti, G., Gallo, M.P., et al. Catestatin improves post-ischemic left ventricular function and decreases ischemia/reperfusion injury in heart. Cellular and Molecular Neurobiology. 2010.
Zhang, D., Shooshtarizadeh, P., Laventie, B.J., et al. Two chromogranin a-derived peptides induce calcium entry in human neutrophils by calmodulin-regulated calcium independent phospholipase A2. PLoS One. 2009.
Fung, M.M., Salem, R.M., Mehtani, P., et al. Direct vasoactive effects of the chromogranin A (CHGA) peptide catestatin in humans in vivo. Clinical and Experimental Hypertension. 2010.