Table 2.

Characteristics of animal studies included in the systematic review of the effects of ginseng and ginsenosides on ADHD.

First author, Year	Species (Sample size (E/C))	Age range or mean age	Model	Weight	Experimental group	Control group	Outcome measure - Behavioral tests	Outcome measure - Biochemical analysis
Animal studies
Nam, 2014	ICR mice (E/C1/C2/C3 = 10/10/10/10)(M/F = 20/20)	Postnatal day 21	PCB-exposed model	Not reported	Ginsenoside Rg3 + terpenoid-strengthened Ginkgo biloba 200 mg/kg, p.o., qd, 15 d	C1 PCB + Vehicle, 15 d C2 PCB + Methylphenidate 5 mg/kg, i.p., qd, 15 d C3 PCB + K252a 0.1 or 0.3 mg/kg, i.p., qd, 15 d	Open-field test -total distance moved↓, entry latency to central zone↑ (vs C1, C3), distance moved in central zone↓ (vs C1) Elevated plus-maze -number of open arm entries↓, Time spent in open arm↓ (vs C1, C3) Object-based attention test↑ (vs C1, C3)	prefrontal cortex BDNF↑, p-TrkB↑ (vs C1, C3) DAT↑, NET↑ (vs C1, C3) ROS↓, Protein carbonyl↓, MDA↓ (vs C1, C3)
Hu, 2012	Rats (E/C1/C2/C3 = 8/8/8/8)(M/F = 16/0)	11 wk	Spontaneously hypertensive rats (SHR) model	E: 285–310 g C: 180–220 g	Ginsenoside Rg1 40 mg/kg, p.o., qd, 14 d	C1 WKY rats C2 SHR rats C3 SHR + Methylphenidate 5 mg/kg, p.o., qd, 14 d	None	Prefrontal cortex Dopamine↑, Norepinephrine n.s. (vs C2) Striatum Dopamine↑, Norepinephrine n.s. (vs C2)
Kim, 2010	Sprague-Dawley (SD) rats (E/C1/C2/C3 = 8/8/8/8)(M/F = 16/0)	3 wk	Neonatal hypoxia-induced hyperactivity model	Not reported	KRG extract 200 mg/kg, p.o., qd, 7 d	C1 neonatal hypoxia + Vehicle, p.o., qd, 7 d C2 control + Vehicle, p.o., qd, 7 d C3 control + KRG extract 200 mg/kg, p.o., qd, 7 d	Open-field test Total arena -Total movement distance↓, Total movement duration↓, Rearing frequency↓, Total angle of head bending n.s. (vs C1) Central arena -Movement distance↓, Movement duration↓, Rearing frequency↓, Total angle of head bending n.s. (vs C1) Rotarod performance -Falling time↑, Falling frequency↓ (vs C1)	Forebrain NET↓ (vs C1)

BDNF, Brain-derived neurotrophic factor; C, Control group; DAT, Dopamine transporter; E, Experimental group; F, Female; KRG, Korean Red Ginseng; M, Male; MDA, Malondialdehyde; n.s., Not significant; NET, Norepinephrine transporter; p-TrkB, Phosphorylated tropomyosin receptor kinase B; PCB, Polychlorinated biphenyls; ROS, Reactive oxygen species; WKY, Wistar Kyoto.

Statistical analysis of the outcomes in animal studies showed between-group differences compared to the negative control group.