Neuroprotective Effects of Lycium barbarum Berry on Neurobehavioral Changes and Neuronal Loss in the Hippocampus of Mice Exposed to Acute Ionizing Radiation

Abstract

Background: Brain exposure to ionizing radiation during the radiotherapy of brain tumor or metastasis of peripheral cancer cells to the brain has resulted in cognitive dysfunction by reducing neurogenesis in hippocampus. The water extract of Lycium barbarum berry (Lyc), containing water-soluble Lycium barbarum polysaccharides and flavonoids, can protect the neuronal injury by reducing oxidative stress and suppressing neuroinflammation. Reseach Design: To demonstrate the long-term radioprotective effect of Lyc, we evaluated the neurobehavioral alterations and the numbers of NeuN, calbindin (CB), and parvalbumin (PV) immunopositive hippocampal neurons in BALB/c mice after acute 5.5 Gy radiation with/without oral administration of Lyc at the dosage of 10 g/kg daily for 4 weeks. Results: The results showed that Lyc could improve irradiation-induced animal weight loss, depressive behaviors, spatial memory impairment, and hippocampal neuron loss. Immunohistochemistry study demonstrated that the loss of NeuN-immunopositive neuron in the hilus of the dentate gyrus, CB-immunopositive neuron in CA1 strata radiatum, lacunosum moleculare and oriens, and PV-positive neuron in CA1 stratum pyramidum and stratum granulosum of the dentate gyrus after irradiation were significantly improved by Lyc treatment. Conclusion: The neuroprotective effect of Lyc on those hippocampal neurons may benefit the configuration of learning related neuronal networks and then improve radiation induced neurobehavioral changes such as cognitive impairment and depression. It suggests that Lycium barbarum berry may be an alternative food supplement to prevent radiation-induced neuron loss and neuropsychological disorders.

Fruits and their phytochemicals in mitigating the ill effects of ionizing radiation: review on the existing scientific evidence and way forward

“…In addition to its hematopoietic protective effects studies have also shown that goji berry possesses neuroprotective effects against radiation-induced damage as observed by reduced levels in the neurobehavioral changes, and it mediates the protective effects at least in part by lowering the neuronal loss in the hippocampus region in laboratory mice. 140 In this study, compared to the radiation alone (5.5 Gy) group, feeding the aqueous extract of Lycium barbarum (10 g per kg body weight daily for 4 weeks) after radiation exposure caused an improvement in animal weight loss, reduced the degree of depressive behaviors, and decreased the spatial memory impairment and the loss of hippocampal neurons. 140 Mechanistic studies have suggested that post-radiation a significant decrease in the levels of NeuN-immunopositive neurons in the hilus of the dentate gyrus region, CB-immunopositive neurons in the CA1 stratum pyramidal and stratum granulosum of the dentate gyrus region and PV-positive neurons in the CA1 stratum pyramidal and stratum granulosum of the dentate gyrus region was mitigated by the administration of the aqueous extract of the berries and the effect is reported to be mediated by preventing neuroinflammation and the levels of oxidative stress 140 (Table 1).…”

Delayed Reaction of Radiation on the Central Nervous System and Bone System in C57BL/6J Mice

“…Increased evidence shows that traditional Chinese medicine (TCM) played a very suitable anti-radiation effect [ 61 ]. Studies have shown that Lycium barbarum extract has a neuroprotective effect on radiation-induced neurobehavioral changes such as cognitive impairment and depression [ 62 ]. From the point of view of antioxidation, many TCMs may play a better role, such as Cistanche deserticola and Houttuynia cordata [ 63 , 64 ].…”

Neuroprotective effects of dietary plants and phytochemicals against radiation-induced cognitive and behavioral deficits: a comprehensive review of evidence and prospects for future research

“…75 Moreover, mice fed with Lycium barbarum polysaccharides (10 g kg −1 , 4 weeks duration) and exposed to 5.5 Gy X-rays were protected against radiation-induced weight loss, memory impairments, depressive behavior, and hippocampal neuronal loss. 83 Regular consumption of wolfberry extract was found to have no significant side effects, indicating its safety. 78,84 Collectively, these findings suggest that Lycium barbarum may be a useful food supplement to prevent radiation-induced neuronal damage and neuropsychological disorders, and further studies are warranted.…”