Table 1.

List of the main assessed and emerging circulating biomarkers in stroke.

Biomarker group	Molecule		Diagnostic or prognostic value(1)			References
Myokines	Irisin			↑	Good prognostic marker of stroke recovery with training	[21, 22]
	Myostatin (GDF-8)	↑	Muscular biomarker of stroke Muscle wasting			[23–26]
	Follistatin			↑	Good prognostic marker of stroke (muscular level)	[27–30]
	PEDF			↑	Good prognostic marker of stroke (angiogenic level)	[31, 32]
	DPP4			↓	Ameliorating stroke recovery	[33, 34]
	Osteonectin (SPARC)			↑	Neural repair following stroke
	FGF-21	↑	Negatively associated with stroke			[35]
Neurotropic factors	Brain derived neurotropic factor (BDNF)	↑	Improvement in stroke recovery Biomarker of stroke onset	↓	Bad prognosis stroke recovery	[17, 19, 20, 36]
	Neurotrophin-3	↑	Biomarkers of stroke onset	↑	Stroke recovery	[37, 38]
	Neurotrophin-4	↑	Biomarkers of stroke onset			[39]
	CNTF	↑	Biomarkers of stroke onset			[40]
Neuropeptides	Neuropeptide Y			↑	Good prognostic biomarker in certain SNP patterns	[41]
	Proenkephalin A			↑	Bad prognosis in stroke progression	[42–44]
	PACAP			↑	Bad prognosis in hemorrhagic stroke progression	[45]
	Substance P			↑	Very bad prognosis in ischemic stroke progression	[46]
Growth factors and GF-like molecules	VEGF	↑	Biomarkers of stroke onset			[47–49]
	IGF-1, IGF-II			↑	Good prognosis in ischemic stroke progression (remodelling)	[50–52]
Cytokines	Interleukin 6 (IL-6)	↑	Stroke onset and progression	↑	Prognostic value to be reviewed	[1, 15, 16]
	Interleukin-33 (IL-33)	↑	Biomarkers of stroke onset	↓	Bad prognosis in ischemic stroke progression	[53]
	Interleukin 15 (IL-15)	↑	Biomarkers of stroke onset	↑	Brain injury	[54]
	Interleukin-11 (IL-11)	↑	Biomarkers of stroke onset			[55, 56]

⁽¹⁾Arrows show the plasma and/or serum level or the level in peripheral blood.