Table 2 Summary of effects of MB or PBM on neurodegenerative disorders and brain injury

AD

• Increases functional MRI activity and improves memory retrieval [200]

• Reduces hyperphosphorylated tau, neurofibrillary tangles, and oxidative stress [234, 235]

• Decreases Aβ levels and Aβ-ABAD binding [226]

• Increases the ability of Aβ phagocytosis [236]

• Attenuates the activity and expression of β-secretase, inhibits the formation of neurotoxic oligomeric Aβ, and improves behavioral results [19, 20, 198]

• Improves spatial learning and memory by significantly reducing Aβ burden [236]

• Exerts neuroprotection by activating the

• Inhibits p-tau aggregation and tau-tau interactions [229, 230]

ERK/CREB pathway and upregulating the expression of BDNF [237]

• Reduces excessive ROS production [17, 22]

• Upregulates Complex IV activates, heme synthesis and mitochondrial function [226, 231,232,233]

• Restores mitochondrial dynamics [8]

TBI

• Decreases edema and lesion volume and improves behavioral scores [163]

• Neurological improvement [246]

• Increases autophagy [242].

• Increases mitochondrial function, improves blood flow, and reduces swelling [244, 247]

• Inhibits excessive ROS production and attenuates mitochondrial dysfunction, cytochrome c release, and neuronal apoptosis [243]

• Decreases oxidative stress, inhibits inflammation, and attenuates apoptosis [244, 247]

Stroke

• Improves behavioral results after focal cerebral ischemia [16]

• Improves neurological rating scores [4, 255, 256]

• Decreases lesion volume, cerebral edema, and gray and white- matter damage [16, 18]

• Stimulates neurogenesis and improves mitochondrial function [4, 262]

• Increases cerebral global glucose uptake and blood flow [251, 252]

• Preserves mitochondrial integrity [263]

• Increases mitochondrial function [9, 252]

• Attenuates mitochondrial fragmentation and restores mitochondrial dynamics [254]

• Preserves mitochondrial structure and function [253]

• Increases mitophagy and preserves mitochondrial membrane potential [253]

• Decreases protein carbonylation, DNA oxidative damage, and lipid peroxidation [254]

Depression

• Improves the symptoms of patients with severe depression [265]

• Improves depressive symptoms [274,275,276,277]

• Selectively inhibits nitric oxide synthase (NOS) [264, 265, 270, 271]

• Improves ATP production and increases activity and expression of mitochondrial Complex IV [208]

PD

• Attenuates dopamine loss and reduces the disruption of mitochondrial function and excessive production of ROS [280,281,282,283,284]

• Reduces cell loss and inhibits inflammatory amoeboid microglia [287,288,289,290]

• Improves Complexes I, II, and III activities, reduces free radical production, and improves behavioral results [252, 285]

• Improves speech, cognition, gait, and freezing episodes in PD patients [291, 292]

• Upregulates brain-derived neurotrophic factor (BDNF) expression [286]

• Improves mitochondrial function and reduces oxidative stress [293]