Spexin (NPQ)

Class Peptide hormone (neuropeptide/adipokine–gut–brain axis)Receptor GALR2

Function

Spexin is a peptide signaling hormone involved in energy metabolism, appetite regulation, lipid signaling, gastrointestinal communication, autonomic regulation, and endocrine metabolic adaptation. The hormone participates in communication pathways linking nutritional status with autonomic and metabolic responses throughout the body.

Spexin influences satiety signaling, adipose tissue metabolism, smooth muscle activity, bile acid physiology, and neuroendocrine communication pathways. It also contributes to regulation of glucose-related signaling, gastrointestinal motility, and energy utilization. Through these actions, spexin functions as a metabolic communication peptide coordinating nutrient-related signaling with autonomic and endocrine adaptation.

Production

Spexin is produced in hypothalamic tissue, gastrointestinal tract, adipose tissue, pancreas, liver, and additional endocrine-responsive organs. Expression occurs within both central nervous system structures and peripheral metabolic tissues, allowing integrated neuroendocrine communication.

The hormone is synthesized as a peptide precursor encoded by the NPQ gene and processed into active signaling fragments. Local tissue production allows paracrine signaling while circulating hormone contributes to broader endocrine metabolic coordination.

Regulation

Spexin production is regulated by nutritional state, glucose metabolism, autonomic signaling, circadian physiology, adipose tissue communication, and hypothalamic endocrine pathways. Feeding status, metabolic demand, and energy availability strongly influence secretion patterns.

Spexin acts through galanin receptor-associated signaling systems that influence calcium pathways, autonomic regulation, smooth muscle activity, and neuroendocrine signaling cascades. Interactions with hypothalamic appetite-regulating pathways and metabolic communication systems contribute to its physiological effects. Through these integrated endocrine and autonomic pathways, spexin coordinates appetite-related signaling, metabolic adaptation, gastrointestinal communication, and energy homeostasis.

Identity & Secretion

Primary Source GlandHypothalamus/brain; also adipose, GI tract (reported peripheral expression)
Secretion PatternMeal/circadian and energy-state dependent (informational).
PrecursorNPQ (C12ORF39) prepropeptide → proteolytic processing to Spexin

Nutrient Requirements

Nutrient Precursors
  • Dietary amino acids support peptide synthesis and secretory pathway maturation.
Required Vitamins
  • Folate, B6, B12 (one-carbon/AA metabolism); Vitamin C (secretory/matrix context)
Required Minerals
  • Magnesium, Zinc (enzyme/signaling cofactors)

Key Foods

  • High-fiber plant foods that promote physiologic satiety and glycemic steadiness: legumes/soy, oats/barley, quinoa, leafy greens, apples/berries, nuts/seeds.

Targets & Signaling

Target Tissues
  • CNS satiety networks, adipose, pancreas, GI tract
Feedback Loops
  • Interacts with leptin–insulin–ghrelin axes and autonomic outputs (informational, non-medical).
Second Messengers
  • PLC/IP3–Ca²⁺ (GALR2); Gi/cAMP↓ (GALR3); ERK/AMPK cross-talk (context).
Pathways Involved
  • GALR2→PLC/IP3–Ca²⁺; GALR3→Gi/cAMP↓; downstream ERK/AMPK nodes (context dependent).

Key Functions

  • Supports satiety pathways, modulates energy utilization, and interfaces with lipid/glucose handling via GALR2/3.

Plant-Based Focus

  • Emphasize soluble-fiber, minimally processed plant meals to align with central satiety and stable post-meal responses (context only).

Clinical Context

Assay Notes
Assay methods vary (precursor vs. peptide; plasma/CSF); values depend on timing and metabolic state.

Linked Knowledge

Phytochemicals
  • Catechins, chlorogenic acid, quercetin (studied in satiety/glycemic modulation contexts).
Amino Acids
  • Tryptophan (serotonergic satiety milieu); arginine (NO/autonomic milieu)
Foods
  • Oats/barley (β-glucan), lentils/beans, chia/flax, apples/berries, leafy greens, almonds/walnuts
Vitamins
  • Folate; B6; B12; Vitamin C
Minerals
  • Magnesium; Zinc
Ailments
  • Appetite/weight and glycemic steadiness contexts (informational, non-medical).

Dietary Modulators

  • High-fiber, water-rich meals; micronutrient sufficiency; diverse polyphenols.

Inhibitors / Activators

Inhibitors
  • Ultra-refined, low-fiber patterns may blunt satiety signaling (context only).
Activators
  • Meal ingestion, gut–brain nutrient sensing, activity-related cues.

Summary

Spexin (NPQ) is a neuropeptide that signals through GALR2/3 to support satiety circuits and energy-metabolic coordination within normal physiology.

SUMMARY OF EFFECTS ON THE BODY

Aligns with plant-forward patterns that favor physiologic satiety and steadier post-meal responses.

Research

Spexin/NPQ and GALR2/3 receptor biology reviews.
Created: Nov 11, 2025 Updated: May 27, 2026