• Nutrition Research and Practice
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• v.9 no.5
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• pp.480-488
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• 2015

BACKGROUND/OBJECTIVES: Alzheimer's disease (AD) is characterized by deficits in memory and cognitive functions. The accumulation of amyloid beta peptide ($A{\beta}$) and oxidative stress in the brain are the most common causes of AD. MATERIALS/METHODS: Caffeic acid (CA) is an active phenolic compound that has a variety of pharmacological actions. We studied the protective abilities of CA in an $A{\beta}_{25-35}$-injected AD mouse model. CA was administered at an oral dose of 10 or 50 mg/kg/day for 2 weeks. Behavioral tests including T-maze, object recognition, and Morris water maze were carried out to assess cognitive abilities. In addition, lipid peroxidation and nitric oxide (NO) production in the brain were measured to investigate the protective effect of CA in oxidative stress. RESULTS: In the T-maze and object recognition tests, novel route awareness and novel object recognition were improved by oral administration of CA compared with the $A{\beta}_{25-35}$-injected control group. These results indicate that administration of CA improved spatial cognitive and memory functions. The Morris water maze test showed that memory function was enhanced by administration of CA. In addition, CA inhibited lipid peroxidation and NO formation in the liver, kidney, and brain compared with the $A{\beta}_{25-35}$-injected control group. In particular, CA 50 mg/kg/day showed the stronger protective effect from cognitive impairment than CA 10 mg/kg/day. CONCLUSIONS: The present results suggest that CA improves $A{\beta}_{25-35}$-induced memory deficits and cognitive impairment through inhibition of lipid peroxidation and NO production.

• BMB Reports
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• v.41 no.9
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• pp.635-639
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• 2008

Acrolein is a highly reactive by product of lipid peroxidation and individuals with neurodegenerative disorders have been shown to contain elevated concentrations of this molecule in the brain. In the present study, we examined the pattern of neurofilament-L (NF-L) modification elicited by acrolein. When NF-L was incubated with acrolein, protein aggregation occurred in a acrolein concentration-dependent manner. Exposure of NF-L to acrolein also led to the generation of protein carbonyl compounds. Through the addition of free radical scavengers we observed a significant decrease in acrolein-mediated NF-L aggregation. These results indicate that free radicals may be involved in the modification of NF-L by acrolein. In addition, dityrosine crosslink formation was observed in acrolein-mediated NF-L aggregates and these aggregates displayed thioflavin T reactivity, reminiscent of amyloid. This study suggests that acrolein-mediated NF-L aggregation might be closely related to oxidative reactions, thus these reactions may play a critical role in neuro-degenerative diseases.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1503-1507
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• 2013

The two major symptoms characterizing Alzheimer's disease are the formation of amyloid-${\beta}$ extracellular deposits in the form of senile plaques and intracellular neurofibrillary tangles (NFTs) that consist of pathological hyperphosphorylated tau protein aggregated into insoluble paired helical filaments (PHFs). Neurons of the central nervous system have appreciable amounts of tau protein, a microtubule-associated protein. To maintain an optimal operation of nerves, the microtubules are stabilized, which is necessary to support cell structure and cellular processes. When the modified tau protein becomes dysfunctional, the cells containing misfolded tau cannot maintain cell structure. One of the pathological hallmarks of Alzheimer's disease is hyperphosphorylated tau protein. This paper shows that the small heat shock protein from humans (Hsp27) reduces hyperphosphorylated tau and prevents hyperphosphorylated tau-induced cell death of the human neuroblastoma cell line SH-SY5Y.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.443-446
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• 2013

In this work, a novel strategy is provided to prepare silver nanoplates by a fibronectin (Fn) nanofibril template. First, Fn molecules were controlled to assemble into amyloid-like nanofibrils in highly concentrated ethanol aqueous solution. The resultant nanofibrils could serve as a soft template to direct the formation of silver nanoplates. It is worth noting that the silver nanoplates are excellent surface-enhanced Raman scattering (SERS) substrate with 4-aminothiophenol (4-ATP) molecule as a test probe. This high active SERS substrate can also be used to detect drug molecule, 2-thiouracil with high sensitivity.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.4
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• pp.273-279
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• 2009

The accumulation of ${\beta}$-amyloid (A${\beta}$) aggregates is a characteristic of Alzheimer's disease (AD). Furthermore, these aggregates have neurotoxic effects on cells, and thus, molecules that inhibit A${\beta}$ aggregate formation could be valuable therapeutics for AD. It is well known that aggregation of A${\beta}$ depends on its hydrophobicity, and thus, in order to increase the hydrophilicity of A${\beta}$, we considered using citrate, an anionic surfactant with three carboxylic acid groups. We hypothesized that citrate could reduce hydrophobicity and increase hydrophilicity of A${\beta}_{1-40}$ molecules via hydrophilic/electrostatic interactions. We found that citrate significantly inhibited A${\beta}_{1-40}$ aggregation and significantly protected SH-SY5Y cell line against A${\beta}_{1-40}$ aggregates-induced neurotoxicity. In details, we examined the effects of citrate on A${\beta}_{1-40}$ aggregation and on A${\beta}_{1-40}$ aggregates-induced cytotoxicity, cell viability, and apoptosis. Th-T assays showed that citrate significantly inhibited A${\beta}_{1-40}$ aggregation in a concentration-dependent manner (Th-T intensity: from 91.3% in 0.01 mM citrate to 82.1% in 1.0 mM citrate vs. 100.0% in A${\beta}_{1-40}$ alone). In cytotoxicity and viability assays, citrate reduced the toxicity of A${\beta}_{1-40}$ in a concentration-dependent manner, in which the cytotoxicity decreased from 107.5 to 102.3% as compared with A${\beta}_{1-40}$ aggregates alone treated cells (127.3%) and the cell viability increased from 84.6 to 93.8% as compared with the A${\beta}_{1-40}$ aggregates alone treated cells (65.3%). Furthermore, Hoechst 33342 staining showed that citrate (1.0 mM) suppressed A${\beta}_{1-40}$ aggregates-induced apoptosis in the cells. This study suggests that citrate can inhibit A${\beta}_{1-40}$ aggregation and protect neurons from the apoptotic effects of A${\beta}_{1-40}$ aggregates. Accordingly, our findings suggest that citrate administration should be viewed as a novel neuroprotective strategy for AD.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.397-404
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• 2009

For standardization of LMK02 quality, Ginsenoside Rg3 of Red Ginseng and Decursin of Angelica gigas Nakai in the constituents of LMK02 were estimated as indicative components. From LMK02 water extract, has been used in vitro test for its beneficial effects on neuronal survival and neuroprotective functions, particularly in connection with APP-related dementias and Alzheimer's disease (AD). $A{\beta}$ oligomer derived from proteolytic processing of the ${\beta}$-amyloid precursor protein (APP), including the amyloid-${\beta}$ peptide ($A{\beta}$), play a critical role in the pathogenesis of Alzheimer's dementia. We determined that oligomer amyloid-${\beta}$ ($A{\beta}$) have a profound attenuation in the increase in rat hippocampus H19-7 cells from. Experimental evidence indicates that LMK02 protects against neuronal damage from cells, but its cellular and molecular mechanisms remain unknown. Using a hippocampus cell line on $A{\beta}$ oligomer-induced neuronal cytotoxicity, we demonstrated that LMK02 inhibits formation of $A{\beta}$ oligomer, which are the behavior, and possibly causative, feature of AD. In the Red Ginseng, the average amounts of Ginsenoside Rg3 were $47.04{\mu}g/g$ and $42.3{\mu}g/g$, 90 % of its weight were set as a standard value. And, in the Angelica gigas Nakai, the average amounts of Decursin were 2.71 mg/g and 2.44mg/g, 90 % of its weight were also set as a standard value. The attenuated $A{\beta}$ oligomer in the presence of LMK02 was observed in the conditioned medium of this $A{\beta}$ oligomer-induced cells under in vitro. In the cells, LMK02 significantly activated antiapoptosis and decreased the production of ROS. These results suggest that neuronal damage in AD might be due to two factors: a direct $A{\beta}$ oligomer toxicity and multiple cellular and molecular neuroprotective mechanisms, including attenuation of apoptosis and direct inhibition of $A{\beta}$ oligomer, underlie the neuroprotective effects of LMK02 treatment.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.3
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• pp.253-260
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• 2020

Alzheimer's disease (AD) is a chronic and progressive neurodegenerative disease that can be described by the occurrence of dementia due to a decline in cognitive function. The disease is characterized by the formation of extracellular and intracellular amyloid plaques. Amyloid beta (Aβ) is a hallmark of AD, and microglia can be activated in the presence of Aβ. Activated microglia secrete pro-inflammatory cytokines. Furthermore, S100A9 is an important innate immunity pro-inflammatory contributor in inflammation and a potential contributor to AD. This study examined the effects of metformin and α-LA on the inflammatory response and NLRP3 inflammasome activation in Aβ- and S100A9-induced BV-2 microglial cells. Metformin and α-LA attenuated inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). In addition, metformin and α-LA inhibited the phosphorylation of JNK, ERK, and p38. They activated the nuclear factor kappa B (NF-κB) pathway and the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome. Moreover, metformin and α-LA reduced the marker levels of the M1 phenotype, ICAM1, whereas the M2 phenotype, ARG1, was increased. These findings suggest that metformin and α-LA are therapeutic agents against the Aβ- and S100A9-induced neuroinflammatory responses.

• Journal of Ginseng Research
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• v.42 no.4
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• pp.401-411
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• 2018

Longevity in medicine can be defined as a long life without mental or physical deficits. This can be prevented by Alzheimer's disease (AD). Current conventional AD treatments only alleviate the symptoms without reversing AD progression. Recent studies demonstrated that Panax ginseng extract improves AD symptoms in patients with AD, and the two main components of ginseng might contribute to AD amelioration. Ginsenosides show various AD-related neuroprotective effects. Gintonin is a newly identified ginseng constituent that contains lysophosphatidic acids and attenuates AD-related brain neuropathies. Ginsenosides decrease amyloid ${\beta}$-protein ($A{\beta}$) formation by inhibiting ${\beta}$- and ${\gamma}$-secretase activity or by activating the nonamyloidogenic pathway, inhibit acetylcholinesterase activity and $A{\beta}$-induced neurotoxicity, and decrease $A{\beta}$-induced production of reactive oxygen species and neuro-inflammatory reactions. Oral administration of ginsenosides increases the expression levels of enzymes involved in acetylcholine synthesis in the brain and alleviates $A{\beta}$-induced cholinergic deficits in AD models. Similarly, gintonin inhibits $A{\beta}$-induced neurotoxicity and activates the nonamyloidogenic pathway to reduce $A{\beta}$ formation and to increase acetylcholine and choline acetyltransferase expression in the brain through lysophosphatidic acid receptors. Oral administration of gintonin attenuates brain amyloid plaque deposits, boosting hippocampal cholinergic systems and neurogenesis, thereby ameliorating learning and memory impairments. It also improves cognitive functions in patients with AD. Ginsenosides and gintonin attenuate AD-related neuropathology through multiple routes. This review focuses research demonstrating that ginseng constituents could be a candidate as an adjuvant for AD treatment. However, clinical investigations including efficacy and tolerability analyses may be necessary for the clinical acceptance of ginseng components in combination with conventional AD drugs.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.854-857
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• 2011

POMT7, which is an O-methyltransferase from poplar, transfers a methyl group to several flavonoids that contain a 7-hydroxyl group. POMT7 has been shown to have a higher affinity toward quercetin, and the reaction product rhamnetin has been shown to inhibit the formation of beta-amyloid. Thus, rhamnetin holds great promise for use in therapeutic applications; however, methods for mass production of this compound are not currently available. In this study, quercetin was biotransformed into rhamnetin using Escherichia coli expressing POMT7, with the goal of developing an approach for mass production of rhamnetin. In order to maximize the production of rhamnetin, POMT7 was subcloned into four different E. coli expression vectors, each of which was maintained in E. coli with a different copy number, and the best expression vector was selected. In addition, the S-adenosylmethionine biosynthesis pathway was engineered for optimal cofactor production. Through the combination of optimized POMT7 expression and cofactor production, the production of rhamnetin was increased up to 111 mg/l, which is approximately 2-fold higher compared with the E. coli strain containing only POMT7.

• Journal of Korean Neurosurgical Society
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• v.37 no.2
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• pp.124-128
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• 2005

Objective: Congenital bilateral perisylvian syndrome(CBPS) has been defined as a characteristic malformative perisylvian polymicrogyria(PMG) in patients with clinical symptoms of pseudobulbar palsy and epileptic seizures. For the present study, we investigate clinicopathologic features of CBPS associated with timing of lesion formation. Methods: Clinicopathologic features of CBPS from 6 patients with surgical resection of the cerebral lesions due to medically intractable seizures were studied. Results: Seizure onset ranged from 1 to 10years (average 6.7years) of age, and average duration of seizure was 23years. All had complex partial seizures, and two patients had additional tonic clonic seizures. Magnetic resonance (MR) images showed polymicrogyria, atropic gyri with gliosis. In the histopathologic examination, the cortical lesions revealed features of ulegyria; atrophic and sclerotic gyri, laminar loss of neurons, extensive lobular gliosis throughout the gray and white matter, neuronoglial nodule formation, and many amyloid bodies. Unlayered or four-layered PMG was not identified. Conclusion: Above data suggest that CBPS might be caused by ulegyria resulting from developmental cortical defect during early fetal stage or acquired hypoxic/ischemic injury in prenatal or postnatal life.