Precautionary effects of RedLiriope platyphyllaon NGF secretion and Aβ42 deposition under the preclinical stage of Alzheimer's disease in Tg2576 mice

Abstract

Red Liriope platyphylla (RLP) has been manufactured from Liriope platyphylla (L. platyphylla, LP) roots using steaming process and investigated as a curative agent for treatment of diabetes, obesity and neurodegenerative disorders. To examine the precautionary effects of aqueous extract RLP (AEtRLP) on the preclinical stages of Alzheimer's Disease (AD), alterations of the key factors influencing AD were investigated in Tg2576 mice after AEtRLP7 treatment for 4 months. Aβ-42 peptides level was significantly decreased in the brain of AEtRLP7-treated Tg2576 mice compared to vehicle-treated Tg2576 mice, although significant differences on improving behavioral defects were not observed in the same group. The concentration of nerve growth factor (NGF) in serum was also higher in AEtRLP7-treated Tg2576 mice than vehicle-treated Tg2576 mice. However, the phosphorylation of TrkA and Erk among the downstream effectors of the high affinity NGF receptor was significantly lower in AEtRLP7-treated Tg2576 mice. A similar pattern was observed in the expression level of downstream effectors within low affinity NGF receptor. Overall, these results suggest that AEtRLP7 can contribute to preventing the production and deposition of Aβ-42 peptides during the early progression stage of AD in the brain of Tg2576 mice through increased NGF secretion.

Neuroprotective effects of Liriope platyphylla extract against hydrogen peroxide-induced cytotoxicity in human neuroblastoma SH-SY5Y cells

“…Furthermore, previous studies suggested that LP activated the neurogenic signaling pathway, and ameliorated the symptoms of neurodegenerative disease. LP prevented Aβ 1–42 peptide deposition and increased NGF production in Tg2576 mice [ 17 , 18 ]. Previous reports evaluated the relationship between the active compounds in LP and neuronal differentiation/brain-derived neurotrophic factor (BDNF)-mediated memory.…”

“…Previous studies suggested that LP and its active compounds may exert beneficial effects in cases of viral infection, inflammation, asthma, diabetes, and obesity by modulating the mitogen-activated protein kinase (MAPK)/nuclear translocation of nuclear factor-κB (NF-κB) signaling pathway, as well as inflammatory proteins [ 12 – 16 ]. LP and red LP extract were reported to decrease amyloid-beta (Aβ 1–42 ) peptide levels in the brain and increase nerve growth factor (NGF) levels in the serum of NSE/hAPP swe transgenic mice and Tg2576 mice respectively [ 17 , 18 ]. However, the anti-apoptotic and neuroprotective effects of LP against hydrogen peroxide (H 2 O 2 )-induced neuronal cell loss have not been studied.…”

Jowiseungchungtang Inhibits Amyloid-β Aggregation and Amyloid-β-Mediated Pathology in 5XFAD Mice

“…Moreover, lignans, the bioactive compounds from Schisandrae Fructus, reduced Aβ 1–42 secretion in the hippocampus of mice [47]. Another constituent, the extract of red Liriope platyphylla which is made from Liriopis Tuber, decreases Aβ 1–42 levels in the brain of Tg2576 mice [48]. These studies might explain that the above-mentioned constituents may be involved in the anti-Aβ accumulation effects of JWS.…”

Phytochemical and pharmacological overview on <i>Liriopes radix</i>

“…Administration of LR (fractions T, A, C, and M) inhibited cholinesterase activity by 56, 64, 56, and 44 , respectively [1]. A-42 peptides level was significantly decreased in the brain, while the level of NGF in serum was higher of AEtRLP7-treated Tg2576 mice [58] and NSE/hAPPsw Tg mice [59]. The TrkA and P75 NTR proteins were suppressed along with production of A-42, -secretase, APH-1, and nicastrin (NCT), whereas the expression of PS-2 and Pen-2 was maintained or increased in NSE/hAPPsw Tg mice [59].…”