NPY and POMC neuropeptide levels are significantly lower in both bipolar and unipolar depression patients

Serum NPY and POMC levels were significantly lower in both unipolar and bipolar depression patients compared to controls (p=0.001), though levels did not significantly differ between the two mood disorder types.

Solak, Hatice et al.·BMC psychiatry·2025·
RPEP-136392025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Not classified
Evidence
Not graded
Sample
Not reported

What This Study Found

NPY and POMC: significantly lower in both UP and BP vs controls (p=0.001). NPY: lower in UP vs BP (NS). POMC: lower in BP vs UP (NS). No correlation with HAM-D, sleepiness, or eating scales.

Key Numbers

How They Did This

Case-control study: 26 UP + 28 BP patients + 27 healthy controls. Serum NPY and POMC quantification. HAM-D, Epworth Sleepiness Scale, Three-Factor Eating Questionnaire.

Why This Research Matters

Identifying neuropeptide biomarkers that are altered in mood disorders could enable objective diagnostic testing and reveal new therapeutic targets, especially given the difficulty of distinguishing bipolar from unipolar depression clinically.

The Bigger Picture

This adds to evidence that mood disorders involve fundamental changes in neuropeptide signaling. The shared NPY/POMC reduction across bipolar and unipolar depression may reflect a common stress-related mechanism rather than a disease-specific marker.

What This Study Doesn't Tell Us

Small sample sizes. Serum levels may not reflect brain neuropeptide concentrations. Cross-sectional—cannot determine causation. Medication effects not fully controlled. No significant differentiation between BP and UP.

Questions This Raises

  • ?Could NPY/POMC levels help predict treatment response in mood disorders?
  • ?Do levels change with treatment response?
  • ?Are the reductions a cause or consequence of mood disorders?

Trust & Context

Key Stat:
NPY + POMC reduced in depression Both neuropeptides were significantly lower in unipolar and bipolar depression patients compared to healthy controls, suggesting shared stress-response dysregulation
Evidence Grade:
Small case-control study. Significant findings but needs replication in larger cohorts. First to examine NPY/POMC with eating behavior in mood disorders.
Study Age:
Published in 2025.
Original Title:
Evaluation of Proopiomelanocortin (POMC) and neuropeptide Y (NPY) levels in bipolar and unipolar patients.
Published In:
BMC psychiatry, 25(1), 707 (2025)
Database ID:
RPEP-13639

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

What are NPY and POMC?

NPY (neuropeptide Y) regulates stress responses, appetite, and mood. POMC (proopiomelanocortin) is a precursor for multiple hormones involved in stress response and metabolism. Both were significantly reduced in depression patients, suggesting that mood disorders involve disrupted neuropeptide signaling.

Could blood tests for these peptides diagnose depression?

Not yet. While both NPY and POMC were lower in depressed patients, the levels did not distinguish between bipolar and unipolar depression—a key clinical challenge. The findings support further research but are not ready for diagnostic use.

Read More on RethinkPeptides

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Cite This Study

RPEP-13639·https://rethinkpeptides.com/research/RPEP-13639

APA

Solak, Hatice; Gokcen, Onur. (2025). Evaluation of Proopiomelanocortin (POMC) and neuropeptide Y (NPY) levels in bipolar and unipolar patients.. BMC psychiatry, 25(1), 707. https://doi.org/10.1186/s12888-025-07147-x

MLA

Solak, Hatice, et al. "Evaluation of Proopiomelanocortin (POMC) and neuropeptide Y (NPY) levels in bipolar and unipolar patients.." BMC psychiatry, 2025. https://doi.org/10.1186/s12888-025-07147-x

RethinkPeptides

RethinkPeptides Research Database. "Evaluation of Proopiomelanocortin (POMC) and neuropeptide Y ..." RPEP-13639. Retrieved from https://rethinkpeptides.com/research/solak-2025-evaluation-of-proopiomelanocortin-pomc

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.