Cholinergic dysfunction and oxidative stress are the most common causes of Alzheimer's disease (AD). Safflower seed contains various anti-oxidant and cholinergic improvement compounds, such as serotonin and its derivatives. In the present study, we investigated the protective effects and mechanisms of a safflower seed extract on scopolamine-induced memory impairment in a mouse model. The safflower seed extract was orally administered at a dose of 100 mg kg⁻¹ day⁻¹, and then behavior tests (such as T-maze and novel object recognition tests) were conducted. Acetyl cholinesterase (AChE) activity, reactive oxygen species (ROS) production, and antioxidant enzymes in the brain were measured. In behavior tests, the novel route exploration and object recognition were improved by the administration of the safflower seed extract, which suggests that the safflower seed extract improves memory function in the scopolamine-treated mouse model. In addition, the safflower seed extract-administered group showed inhibition of the AChE activity and improved cholinergic dysfunction. Furthermore, the administration of the safflower seed extract resulted in lower ROS production and higher antioxidant enzyme levels as compared to the scopolamine-treated group, suggesting the protective role of the safflower seed extract against oxidative stress. The results of the present study suggest that the safflower seed extract improves scopolamine-induced memory deficits via the inhibition of cholinergic dysfunction and oxidative stress. Therefore, safflower seeds might become a promising agent for memory improvement in AD patients.

This study aims to investigate the protective effects and mechanisms of pectolinarin against oxidative stress-induced cell damage in SH-SY5Y cells. Neurodegenerative diseases—such as Alzheimer’s disease—are potentially associated with oxidative stress, which causes excessive production of reactive oxygen species (ROS) that damage DNA and proteins in neuronal cells. The results of this study demonstrate that pectolinarin can scavenge hydroxyl and nitric oxide radicals in a concentration-dependent manner. Moreover, pectolinarin significantly increased cell viability while reducing ROS production and LDH release in the hydrogen peroxide (H₂O₂)-induced control group. Additionally, Pectolinarin recovered protein expression from H₂O₂-altered levels back to close-to-normal SH-SY5Y cell levels for components of the oxidative stress, inflammation, and apoptosis pathways—such as nuclear factor erythroid 2-related factor 2 (Nrf2), kelch-like ECH-associated protein (Keap1), anti-heme oxygenase 1 (HO-1), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), B-cell lympho-ma-2 (Bcl-2) protein, and Bcl-2-associated X protein (Bax). These findings suggest that pectolinarin has the potential to be used as a plant material for functional foods to be applied in the treatment of neurodegenerative diseases, such as Alzheimer’s disease, by mitigating oxidative stress-induced damage to neuronal cells.

Flavonoids, quercitrin, isoquercitrin (IQ), and afzelin, were isolated from ethyl acetate fraction of Acer okamotoanum. We investigated anti-obesity effects and mechanisms of three flavonoids from A. okamotoanum in the differentiated 3T3-L1 cells. The differentiated 3T3-L1 cells increased triglyceride (TG) contents, compared with non-differentiated normal group. However, treatments of three flavonoids from A. okamotoanum decreased TG contents without cytotoxicity. In addition, they showed significant down-regulation of several adipogenic transcription factors, such as γ-cytidine-cytidine-adenosine-adenosine-thymidine/enhancer binding protein -α, -β, and peroxisome proliferator-activated receptor-γ, compared with non-treated control group. Furthermore, treatment of the flavonoids inhibited expressions of lipogenesis-related proteins including fatty acid synthase, adipocyte protein 2, and glucose transporter 4. Moreover, IQ-treated group showed significant up-regulation of lipolysis-related proteins such as adipose triglyceride lipase and hormone-sensitive lipase. In addition, flavonoids significantly activated 5′-adenosine monophosphate-activated protein kinase (AMPK) compared to control group. In particular, IQ showed higher inhibition of TG accumulation by regulation of pathways related with both adipogenesis and lipolysis, than other flavonoids. The present results indicated that three flavonoids of A. okamotoanum showed anti-obesity activity by regulation of adipocyte differentiation, lipolysis, and AMPK signaling, suggesting as an anti-obesity functional agents.

Obesity induced by high-fat diet (HFD) and accumulation of amyloid beta (Aβ) are known as a risk factor of Alzheimer's disease. We previously identified isoquercitrin (IQ) as an active compound of Acer okamotoanum. In the present study, we investigated the protective effects of the active ethyl acetate (EtOAc) fraction from A. okamotoanum and IQ on HFD and Aβ_25–35-induced cognitive impairment mice. C57BL/6J mice were fed with HFD for 10 weeks and then Aβ_25–35 was injected intracerebroventricularly (i.c.v.). The EtOAc fraction of A. okamotoanum and IQ were administered orally for 4 weeks at 100 and 10 mg kg⁻¹ day⁻¹, respectively. Learning and memory functions were evaluated using behavioral tests including T-maze, object recognition and Morris water maze tests. The HFD and Aβ_25–35 injection significantly impaired cognitive and memory function. However, administration of A. okamotoanum and IQ improved spatial cognitive ability and object recognition ability in T-maze and novel object recognition tests. In addition, A. okamotoanum and IQ-administered groups showed enhanced learning and memory function compared with HFD and Aβ_25–35-induced cognitive impairment mice in the Morris water maze test. Furthermore, administration of A. okamotoanum and IQ attenuated oxidative stress in the brain via inhibition of reactive oxygen species production, lipid peroxidation, and nitric oxide formation. Therefore, we suggest that A. okamotoanum and IQ improve HFD- and Aβ_25–35-induced cognitive impairment by inhibition of oxidative stress, and A. okamotoanum and IQ might be potential candidates for prevention and treatment of obesity- and Aβ-induced cognitive impairment.

This study determined acteoside and its content in Abeliophyllum distichum via HPLC/UV and LC/ESI-MS to obtain insights into the potential use of this plant as an antioxidant agent. Moreover, 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl (^•OH), and O₂⁻ radical scavenging activity assays were performed to assess in vitro antioxidative activity. The DPPH, ^•OH, and O₂⁻ radical scavenging activities of A. distichum leaf EtOH extracts at a 250 μg/mL concentration were 88.32%, 94.48%, and 14.36%, respectively, whereas those of stem extracts at the same concentration were 88.15%, 88.99%, and 15.36%, respectively. The contents of acteoside in A. distichum leaves and stems were 162.11 and 29.68 mg/g, respectively. Acteoside was identified as the main antioxidant compound in A. distichum leaves, which resulted in DPPH, ^•OH, and O₂⁻ radical scavenging activities of 82.84%, 89.46%, and 30.31%, respectively, at a 25 μg/mL concentration. These results indicate that A. distichum leaves and stems containing the antioxidant acteoside can be used as natural ingredients for functional and nutritional supplements.