We investigated the antioxidant and immune-enhancing effects of the extracts from Allium hookeri leaves and roots (AHL and AHR) in in vitro and in vivo models. Their antioxidant effects were determined by total phenolic content (TPC), DPPH and ABTS radical scavenging activities, and superoxide dismutase and catalase activities. The immunomodulatory effects were evaluated by nitric oxide (NO) production and cytokine concentrations produced from RAW 264.7, and by serum IgA and IgG levels, cytokine levels, and NK cell activities in the immunosuppressed C57BL/6 mice. AHL and AHR extracts improved antioxidant activities and productions of NO and cytokines without cytotoxicity in the RAW 264.7 cells. AHL and AHR groups showed significantly higher serum IgA and IgG levels, Th1 cytokine concentrations, splenocyte proliferations, and NK cell activities than the NC group which was not treated with AHL or AHR extract. AHR extract showed higher values than AHL extract in the factors evaluated in this study. The results show that they have high antioxidant and immunomodulatory effects and can be used as novel potential therapeutic candidates to treat related diseases and to improve public health.

/pdf/antioxidant-and-immune-stimulating-effects-of-allium-hookeri-12o9gar1.pdf

Antioxidant and Immune Stimulating Effects of Allium hookeri Extracts in the RAW 264.7 Cells and Immune-Depressed C57BL/6 Mice

ABSTRACT Background: Prenatal alcohol exposure (PAE) causes behavioral deficits and increases risk of metabolic diseases. Alzheimer’s Disease (AD) is a neurodegenerative disease that has a higher risk in adults with metabolic diseases. Both present with persistent neuroinflammation. Objectives: We tested whether PAE exacerbates AD-related cognitive decline in a mouse model (3xTg-AD; presenilin/amyloid precursor protein/tau), and assessed associations among cognition, metabolic impairment, and microglial reactivity. Methods: Alcohol-exposed (ALC) pregnant 3xTg-AD mice received 3 g/kg alcohol from embryonic day 8.5–17.5. We evaluated recognition memory and associative memory (fear conditioning) in 8–10 males and females per group at 3 months of age (3mo), 7mo, and 11mo, then assessed glucose tolerance, body composition, and hippocampal microglial activation at 12mo. Results: ALC females had higher body weights than controls from 5mo (p < .0001). Controls showed improved recognition memory at 11mo compared with 3mo (p = .007); this was not seen in ALC mice. Older animals froze more during fear conditioning than younger, and ALC mice were hyper-responsive to the fear-related cue (p = .017). Fasting blood glucose was lower in ALC males and higher in ALC females than controls. Positive associations occurred between glucose and fear-related context (p = .04) and adiposity and fear-related cue (p = .0002) in ALC animals. Hippocampal microglial activation was higher in ALC than controls (p < .0001); this trended to correlate with recognition memory. Conclusions: ALC animals showed age-related cognitive impairments that did not interact with AD risk but did correlate with metabolic dysfunction and somewhat with microglial activation. Thus, metabolic disorders may be a therapeutic target for people with FASDs.

Prenatal alcohol exposure causes persistent microglial activation and age- and sex- specific effects on cognition and metabolic outcomes in an Alzheimer’s Disease mouse model

Oxidative stress and cellular senescence in dermal papilla cells (DPCs) are major etiological factors causing hair loss. In this study, the effect of the Allium hookeri extract (AHE) on hair-inductive and anti-oxidative properties was investigated in human DPCs. As a result, it was found that a non-cytotoxic concentration of the extracts increased the viability and size of the human DPC spheroid, which was associated with the increased expression of hair-growth-related genes in cells. To determine whether or not these effects could be attributed to intracellular anti-oxidative effects, liquid chromatography-mass spectrometry alongside various biochemical analyses are conducted herein. An ingredient called alliin was identified as one of the main components. Furthermore, AHE treatment induced a significant decrease in H2O2-mediated cytotoxicities, cell death, and cellular senescence in human DPCs. Upon analyzing these results with a molecular mechanism approach, it was shown that AHE treatment increased β-Catenin and NRF2 translocation into the nucleus while inhibiting the translocation of NF-κB (p50) through p38 and PKA-mediated phosphorylations of GSK3β, an upstream regulator of those proteins. These results overall indicate the possibility that AHE can regulate GSK3β-mediated β-Catenin, NRF2, and NF-κB signaling to enhance hair-inductive properties and ultimately protect against oxidative stress-induced cellular damage in human DPCs.

/pdf/effects-of-allium-hookeri-extracts-on-hair-inductive-and-2nq4ueie.pdf

Effects of Allium hookeri Extracts on Hair-Inductive and Anti-Oxidative Properties in Human Dermal Papilla Cells

Jieun Jung, Jeong Wook Heo, Ji Su Kim, Un Yul Jeong, Ui-Jin Bae, Ha Na Jang, Chang Ki Shim, Yoonjo Joung, and Sung Hyen Lee. Journal of the Korean Society of Food Science and Nutrition 2022;51:1355-63. https://doi.org/10.3746/jkfn.2022.51.12.1355 

Functionality of Allium hookeri Leaves and Roots Grown in a Hydroponic Plant Factory Using Artificial Lights

Allium cepa L. (onion) has been reported to have various pharmacological effects, such as preventing heart disease, and improving antimicrobial activity and immunological effects. The Republic of Korea produced 1,195,563 tons of onions (2022). The flesh of onion is used as food while the onion skin (OS) is thrown away as an agro-food by-product and is considered to induce environmental pollution. Thus, we hypothesize that increasing usage of OS as functional food material could help protect from the environment pollution. The antioxidant effects and immune-enhancing effects of OS were evaluated as functional activities of OS. In this study, OS showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and xanthine oxidase (XO) inhibitory activity. The antioxidant activities increased in a dose-dependent manner. The IC50 values of DPPH, ABTS radical scavenging activity, and XO inhibitory activity were 954.9 μg/mL, 28.0 μg/mL, and 10.7 μg/mL, respectively. Superoxide dismutase and catalase activities of OS in RAW 264.7 cells were higher than those of the media control. There was no cytotoxicity of OS found in RAW 264.7 cells. Nitric oxide and cytokines (IL-1β, IL-6, IFN-γ, and TNF-α) concentrations in RAW 264.7 cells significantly increased in a dose dependent manner. Immune-stimulating effects of OS were evaluated in immunosuppressed mice induced by cyclophosphamide. White blood cell count and the B cell proliferation of splenocytes were higher in OS100 (OS extract 100 mg/kg body weight) and OS200 (OS extract 200 mg/kg body weight) groups than in the negative control (NC) group. Serum IgG and cytokine (IL-1β and IFN-γ) levels were also higher in OS100 and OS200 groups than in the NC group. OS treatment increased NK cell activity compared with the NC group. The results suggested that OS can improve antioxidant and immune stimulating effects. The use of OS as functional supplement can reduce the agro-food by-product and it may contribute to carbon neutrality.

/pdf/antioxidant-and-immune-stimulating-effects-of-allium-cepa-1g1sovhv.pdf

Antioxidant and Immune Stimulating Effects of Allium cepa Skin in the RAW 264.7 Cells and in the C57BL/6 Mouse Immunosuppressed by Cyclophosphamide

This study was conducted to evaluate and to increase the usage of the whole onion (Allium cepa L.), which is composed of a small bulb and many leaves that are discarded as by-products before the bulbs grow. Whole onions are harvested early in immature condition, which allows the other onion bulbs to grow well. We compared its functional activities with those of quercetin, which is one of its major components. The antioxidant activities of ethanol extract from the whole onion (WOEE) were measured by DPPH and ABTS radical scavenging activities, and superoxide dismutase (SOD) and catalase (CAT) activities. The anti-inflammatory effects of WOEE were investigated in RAW 264.7 macrophages treated with LPS by analyzing cytokine levels and expressions using ELISA kits and RT-PCR assays, respectively. WOEE showed high antioxidant effects on DPPH and ABTS radical scavenging activities, and SOD and CAT activities. WOEE significantly reduced the production of nitric oxide, IL-1β, IL-6, and TNF-α, and/or their mRNA expressions in a dose-dependent manner. The results indicated that whole onions had antioxidant and anti-inflammatory effects, which were comparable with quercetin and may be used as a novel potential therapeutic candidate.

/pdf/antioxidant-and-anti-inflammatory-effects-of-ethanol-extract-3it5g1s2.pdf

Antioxidant and Anti-Inflammatory Effects of Ethanol Extract from Whole Onion (Allium cepa L.) with Leaves

This study sought to investigate the antioxidant and immune-stimulatory effects of different Curcuma longa (C. longa) extracts based on their color (random, light, medium, dark orange), the soil of cultivation (clay, granite), drying temperature (50∼80℃), and extraction methods (water, ethanol). The antioxidant factors of C. longa were determined by the total phenolic content and DPPH and ABTS radical scavenging activities. The nitric oxide (NO) production of the macrophage cell line (RAW264.7) and the proliferation of splenocytes were investigated to assess the immune-enhancing effects of C. longa. The antioxidant activity was higher in the dark color and the ethanol extracts. All the types of extracts were nontoxic and enhanced the production of NO in RAW264.7 at less than 250 ㎍/mL of C. longa. When mouse splenocytes were exposed to various concentrations of hot water or ethanol extracts of C. longa with media, concanavalin A (Con A), lipopolysaccharide (LPS), and cyclophosphamide (CPA), their proliferation increased. Specifically, the 70% ethanol extract of C. longa showed the highest levels of splenocyte proliferation among all samples. These results suggest that the antioxidant and immune-stimulating activities of C. longa were most affected by the extracting solvent rather than color, soil in which it was cultured, and drying temperature. Appropriate extraction methods for C. longa should be researched further to develop good healthy foods with high antioxidant and immune-enhancing activities. 

Antioxidant and Immune-Enhancing Effects of Curcuma longa Extracts

This study was conducted to evaluate whether Allium hookeri can control diabetic symptoms. Aqueous extract (AE1: 100 mg/kg BW, AE2: 200 mg/kg BW) and ethanol extract (EE1: 100 mg/kg BW, EE2: 200 mg/kg BW) of A. hookeri were orally administrated to diabetic mice (C57BL/J-db/db) for 8 weeks. The negative (NC) and the positive (PC) control groups were treated with 0.9% saline and metformin (150 mg/kg BW), respectively. Glucose and lipid profile (triglyceride, total cholesterol (TC), LDL-C, and HDL-C) as biochemical parameters, toxicological factors such as liver/kidney functional parameters (ALT, AST, BUN, and Cr), and NK cell activity in blood were measured. Oral glucose tolerance test (OGTT) and histopathological examination were also conducted. Compared with the NC group, AE and EE decreased blood glucose, HbA1c, area under the curve (AUC) during OGTT, and leptin levels while increasing adiponectin levels. Serum lipid profiles and toxicological factors levels were reduced by the A. hookeri extract. Interestingly, HDL-C, glomerular mesangial expansion score in the kidney, and NK cell activity were effectively controlled in EE groups. Based on the results, EE is considered to be more effective in reducing high blood glucose, lipid profile, and related factor levels than AE, and is comparable to metformin in some biomarkers. It can be presumed that EE can more effectively control the major anomalies in the diabetic model than AE, and it may be used to prevent diabetic symptoms without toxicity in the Type 2 diabetic model.

/pdf/anti-diabetic-effects-of-allium-hookeri-extracts-prepared-by-2mfz0l9y.pdf

U. Jeong

Papers

Antioxidant and Anti-Inflammatory Effects of Ethanol Extract from Whole Onion (Allium cepa L.) with Leaves

Antioxidant and Immune Stimulating Effects of Allium hookeri Extracts in the RAW 264.7 Cells and Immune-Depressed C57BL/6 Mice

Antioxidant and Immune-Enhancing Effects of Curcuma longa Extracts

Anti-Diabetic Effects of Allium hookeri Extracts Prepared by Different Methods in Type 2 C57BL/J-db/db Mice

Functionality of Allium hookeri Leaves and Roots Grown in a Hydroponic Plant Factory Using Artificial Lights