. 2024 May 29;9:138. doi: 10.1038/s41392-024-01841-0

Table 1.

Overview of exercise-inducible singling molecules (exerkines)

Exerkine	Described source tissues	Mode of intercellular communication			Refs
Exerkine	Described source tissues	Autocrine	Paracrine	Endocrine	Refs
Peptides and proteins
ANGPT1	Skeletal muscle	✓	✓	✓	²¹⁴
FGF21*	Skeletal muscle	×	×	✓	^190,408
GDF15*	Skeletal muscle	✓	✓	✓	⁴⁰⁹
IL-6*	Skeletal muscle	✓	✓	✓	^410,411
IL-7*	Skeletal muscle	✓	✓	×	⁴¹²
IL-8*	Skeletal muscle endothelium	✓	✓	×	^230,413
IL-15*	Skeletal muscle	✓	✓	✓	^144,162
Musclin	Skeletal muscle	✓	✓	×	⁴¹⁴
Myonectin*	Skeletal muscle	×	×	✓	^134,415
NTN	Skeletal muscle	✓	✓	×	¹⁴⁶
SPARC*	Skeletal muscle	✓	✓	×	^130,131
VEGF*	Skeletal muscle	✓	✓	✓	^416–420
FN1	Skeletal muscle	×	×	✓	²⁵⁰
FST*	Skeletal and cardiac muscle, hepatic	×	×	✓	^{239,421–423}
FSTL1*	Adipose, skeletal muscle, cardiac muscle	✓	✓	✓	^{31,32,424,425}
Fractalkine*	Skeletal muscle, endothelium	×	✓	✓	^145,150,426
Irisin*	Skeletal muscle and adipose	✓	✓	✓	^{30,180,183,288,427–429}
ANGPTL4*	Skeletal muscle, adipose, hepatic	✓	✓	✓	^97,243,244
Adiponectin*	Adipose	×	✓	✓	^430–432
Apelin*	Adipose	×	✓	✓	^{147,152,433,434}
TGF-β2*	Adipose	✓	✓	✓	¹⁵¹
RCN2	Bone marrow macrophages	×	✓	×	¹²⁴
METRLN	Macrophages	✓	✓	×	^128,186,435
IL-10*	Macrophages	✓	✓	✓	^436–439
IL-1ra*	Blood mononuclear cells	✓	✓	✓	^438–440
Klotho*	Kidney	✓	✓	✓	^132,133,441
SDC4*	Hepatic	✓	✓	✓	^135,442
BDNF*	Nervous, skeletal muscle	✓	✓	✓	^{127,198,443,444}
NRG1*	Endothelium	×	✓	×	^176,445
Decorin*	Skeletal muscle	✓	✓	✓	^337,446
Cathepsin B*	Skeletal muscle	✓	×	✓	^204,447
GPLD1*	Hepatic	×	×	✓	²¹⁰
PF4	Platelets	×	×	✓	^205–208
Adropin*	Hepatic	✓	×	✓	^{248,249,448,449}
Clusterin*	Unclear	×	×	✓	^209,450
HSPs*	Various	✓	✓	✓	^451,452
Tissue metabolites and lipids
12,13-diHOME*	Adipose	×	✓	×	⁵⁶
KYNA*	Skeletal muscle	×	✓	✓	^185,453
NO*	Endothelium	✓	✓	✓	^261,454
ROS*	Skeletal muscle	✓	✓	✓	⁴⁵⁵
Catecholamines*	Adrenal gland	×	×	✓	⁴⁵⁶
Lactate*	Skeletal muscle	✓	✓	✓	^41,44,457
Succinate*	Skeletal muscle	✓	✓	✓	^52,55
L-BAIBA*	Skeletal muscle	✓	✓	✓	^57,58
Lac-Phe*	Monocytes, macrophages, epithelial cells	×	×	✓	¹⁷
Nucleic acids
microRNAs*	Skeletal muscle	✓	✓	✓	^458–460
lncRNAs*	Skeletal muscle	✓	×	×	^82,461

The selection of exerkines is based on in vivo evidence of signaling molecules that are mobilized in response to acute exercise or exercise training and signal to target tissues. In vitro studies and studies employing external administration of exerkine isolates were not considered. Exerkines that have been investigated in humans are marked with an asterisk

ANGPT1 angiopoietin 1, FGF21 fibroblast growth factor 21, GDF15 growth differentiation factor 1, IL-6 interleukin 6, IL-7 interleukin 7, IL-8 interleukin 8, IL-15 interleukin 15, NTN neurturin, SPARC secreted protein acidic and rich in cysteine, VEGF vascular endothelial growth factor, FST follistatin, FSTL1 follistatin-like 1, ANGPTL4 angiopoietin-like 4, TGF- β2 transforming growth factor β-2, METRLN Meteorin Like, Glial Cell Differentiation Regulator, RCN2 reticulocalbin 2, IL-10 interleukin 10, IL-1ra interleukin 1 receptor antagonist, SDC4 syndecan 4, BDNF brain-derived neurotrophic factor, NRG1 neuregulin 1, HSP heat shock protein, GPLD1 glycosylphosphatidylinositol-specific phospholipase D1, PF4 platelet factor 4, 12,13-diHOME 12,13-dihydroxy-9Z-octadecenoic acid, KYNA kynurenic acid, NO nitric oxide, ROS reactive oxygen species, L-BAIBA β-aminoisobutyric acid, Lac-Phe Lactoylphenylalanine, lncRNA long non-coding RNA