Supplementary Effects of Allium hookeri Extract on Glucose Tolerance in Prediabetic Subjects and C57BL/KsJ-db/db Mice

Allium hookeri (AH) has been used as a nutritional and medicinal food in Asia for many years. Our previous studies have described its anti-diabetic, anti-obesity, and anti-inflammatory activities in animal models and prediabetes. This study investigated whether AH could improve glycemia by modulating insulin secretion in prediabetic subjects through an in-depth study. Eighty prediabetic subjects (100 ≤ fasting plasma glucose < 140 mg/dL) were randomly assigned to a placebo (n = 40) group or an ethanol AH extract (500 mg/day, n = 40) group for 12 weeks. Dietary intake and physical activity, blood glucose (an oral glucose tolerance test for 120 min), insulin (insulin response to oral glucose for 120 min), area under the curve (AUC) of glucose or insulin after oral glucose intake, insulin sensitivity markers, C-peptide, adiponectin, glycated hemoglobin A1c (HbA1c) levels, hematological tests (WBC, RBC, hemoglobin, hematocrit, and platelet count), blood biochemical parameters (ALP, AST, total bilirubin, total protein, albumin, gamma-GT, BUN, creatinine, LD, CK, and hs-CRP), and urine parameters (specific gravity and pH) were examined at both baseline and 12 weeks after supplementation with placebo or AH capsules. Fifty-eight participants (placebo group: 20 men and 10 women; AH group: 13 men and 15 women) completed the study. AH supplementation moderately reduced postprandial blood glucose at 60 min (-6.14 mg/dL, p = 0.061), postprandial insulin levels at 90 min (-16.69 µU/mL, p = 0.017), the glucose AUC at 90 min (-412.52 mg*min/dL, p = 0.021), as well as the insulin AUC at 90 min (-978.77 µU*min/mL, p = 0.021) and 120 min (-1426.41 µU*min/mL, p = 0.015) when compared with the placebo group. However, there were no effects of AH on dietary intake and physical activity; HOMA index; HbAlc; C-peptide; or adiponectin, hematological-, blood biochemical-, and urinary markers. To confirm the effects of AH extract on blood glucose insulin sensitivity, C57BL/6J or C57BL/KsJ-db/db mice were used (n = 8/group). Body weight, fasting plasma glucose level, lipid profiles, liver and renal function, pancreatic histology, and insulin immunoreactivity were assessed. In the diabetic db/db mice, hyperglycemia, which was accompanied by an increase in insulin secretion in diabetic mice, was significantly reduced by AH treatment, resulting in the alleviation of β-cell overcompensation and insulin resistance. We confirmed that AH supplementation can effectively control blood glucose and insulin levels by improving insulin sensitivity and may be a potential agent for glycemic control in subjects with prediabetes and type 2 diabetes mellitus.

Effects of anthocyanin supplementation on blood lipid levels: a systematic review and meta-analysis

Introduction

Dyslipidemia is a major cardiovascular disease risk factor associated with increased mortality. The intake of plant food-derived bioactive compounds is associated with beneficial cardiovascular effects, including decreased blood lipid levels and cardiovascular risk. We aimed to evaluate the effects of anthocyanin intake on blood lipid levels by analyzing relevant randomized controlled trials.

Methods

We searched the PubMed and Embase databases using the "Patient/Population, Intervention, Comparison, and Outcomes" format to determine whether anthocyanin supplementation intervention affected blood lipid levels compared with placebo supplementation in human participants.

Results

A total of 41 studies with 2,788 participants were included in the meta-analysis. Anthocyanin supplementation significantly reduced triglyceride [standardized mean difference (SMD) = -0.10; 95% confidence interval [CI], -0.18, -0.01) and low-density lipoprotein-cholesterol (SMD = -0.16; 95% CI -0.26, -0.07) levels and increased high-density lipoprotein-cholesterol levels (SMD = 0.42; 95% CI 0.20, 0.65).

Discussion

Anthocyanin supplementation significantly improved blood lipid component levels in the included studies. Larger, well-designed clinical trials are needed to further investigate the effects of anthocyanin intake on blood lipid levels and the safety of anthocyanin supplementation for treating dyslipidemia.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021257087, identifier: CRD42021257087.

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

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.

Differences in dietary patterns related to metabolic health by gut microbial enterotypes of Korean adults

Diet has a profound impact on the progression of metabolic syndrome (MetS) into various diseases. The gut microbiota could modulate the effect of diet on metabolic health. We examined whether dietary patterns related to MetS differed according to gut microbial enterotypes among 348 Korean adults aged 18-60 years recruited between 2018∼2021 in a cross-sectional study. The enterotype of each participant was identified based on 16S rRNA gut microbiota data. The main dietary pattern predicting MetS (MetS-DP) of each enterotype was derived using reduced-rank regression (RRR) models. In the RRR models, 27 food group intakes assessed by a semi-quantitative food frequency questionnaire and MetS prediction markers including triglyceride to high-density lipoprotein cholesterol (TG/HDL) ratio and homeostatic model assessment for insulin resistance (HOMA-IR) were used as predictor and response variables, respectively. The MetS-DP extracted in Bacteroides enterotype (B-type) was characterized by high consumption of refined white rice and low consumption of eggs, vegetables, and mushrooms. The MetS-DP derived among Prevotella enterotype (P-type) was characterized by a high intake of sugary food and low intakes of bread, fermented legumes, and fermented vegetables. The MetS-DP of B-type was positively associated with metabolic unhealthy status (OR T3 vs. T1 = 3.5; 95% CI = 1.5-8.2), comparing the highest tertile to the lowest tertile. Although it was not significantly associated with overall metabolic unhealthy status, the MetS-DP of P-type was positively associated with hyperglycemia risk (OR T3 vs. T1 = 6.2; 95% CI = 1.6-24.3). These results suggest that MetS-DP may differ according to the gut microbial enterotype of each individual. If such associations are found to be causal, personalized nutrition guidelines based on the enterotypes could be recommended to prevent MetS.

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

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.

Effects of Platycodon grandiflorum on Gut Microbiome and Immune System of Immunosuppressed Mouse

Platycodon grandiflorum (PG) is a perennial plant that has been used as a traditional remedy to control immune-related diseases. PG was steamed and dried to improve its taste (PGS). The aim of the study was to investigate the effects of PG and PGS (PG-diets) on the gut microbiome and immune system. We treated PG-diets to immunosuppressed mice via cyclophosphamide (CPA) injection. After two weeks of the supplement, we evaluated specific genera related to body weight and serum immunoglobulin levels and analyzed 16S rRNA sequencing and metagenomics statistical analysis. PG-diets groups showed an increased abundance of microorganisms in immunodeficient mice compared to the control group (NC). Moreover, Akkermansia significantly decreased in response to the CPA in the NC group at the genus level, whereas its abundance increased in the PG-diets groups. We also found that the modulation of the gut microbiome by PG-diets was correlated with body weight, IgA, and IgM levels. The results demonstrate that PG-diets may improve the health benefits of immunosuppressed mice by altering the gut microbiome, though not much difference was found between PG and PGS treatments. Finally, this is the first study showing the effects of PGS-diets on the gut microbiome and immune system as a potential nourishing immunity supplement.

Allium hookeri Extracts Improve Scopolamine-Induced Cognitive Impairment via Activation of the Cholinergic System and Anti-Neuroinflammation in Mice

Allium hookeri (AH) is a medicinal food that has been used in Southeast Asia for various physiological activities. The objective of this study was to investigate the activation of the cholinergic system and the anti-neuroinflammation effects of AH on scopolamine-induced memory impairment in mice. Scopolamine (1 mg/kg body weight, i.p.) impaired the performance of the mice on the Y-maze test, passive avoidance test, and water maze test. However, the number of error actions was reduced in the AH groups supplemented with leaf and root extracts from AH. AH treatment improved working memory and avoidance times against electronic shock, increased step-through latency, and reduced the time to reach the escape zone in the water maze test. AH significantly improved the cholinergic system by decreasing acetylcholinesterase activity, and increasing acetylcholine concentration. The serum inflammatory cytokines (IL-1β, IL-6, and IFN-γ) increased by scopolamine treatment were regulated by the administration of AH extracts. Overexpression of NF-κB signaling and cytokines in liver tissue due to scopolamine were controlled by administration of AH extracts. AH also significantly decreased Aβ and caspase-3 expression but increased NeuN and ChAT. The results suggest that AH extracts improve cognitive effects, and the root extracts are more effective in relieving the scopolamine-induced memory impairment. They have neuroprotective effects and reduce the development of neuroinflammation.

Validation of soy isoflavone intake and its health effects: a review of the development of exposure biomarkers

BACKGROUND/OBJECTIVES

It is difficult to consistently demonstrate the health effects of soy isoflavones owing to the multitude of factors contributing to their bioavailability. To accurately verify these health effects, dietary isoflavone intake should be measured using a biologically active dose rather than an intake dose. This concept has been expanded to the development of new exposure biomarkers in nutrition research. This review aims to provide an overview of the development of exposure biomarkers and suggest a novel research strategy for identifying the health effects of soy isoflavone intake.

MATERIALS/METHODS

We cover recent studies on the health effects of soy isoflavones focusing on isoflavone metabolites as exposure biomarkers.

RESULTS

Compared to non-fermented soy foods, fermented soy foods cause an increased concentration of isoflavones in the biofluid immediately following ingestion. The correlation between exposure biomarkers in blood and urine and the food frequency questionnaire was slightly lower than that of corresponding 24-h dietary recalls. Urinary and blood isoflavone levels did not show a consistent association with chronic disease and cancer risk.

CONCLUSION

It is crucial to understand the variable bioavailabilities of soy isoflavones, which may affect evaluations of soy isoflavone intake in health and disease. Further studies on the development of valid exposure biomarkers are needed to thoroughly investigate the health effects of isoflavone.

Taxonomic Composition and Diversity of the Gut Microbiota in Relation to Habitual Dietary Intake in Korean Adults

We investigated associations of habitual dietary intake with the taxonomic composition and diversity of the human gut microbiota in 222 Koreans aged 18-58 years in a cross-sectional study. Gut microbiota data were obtained by 16S rRNA gene sequencing on DNA extracted from fecal samples. The habitual diet for the previous year was assessed by a food frequency questionnaire. After multivariable adjustment, intake of several food groups including vegetables, fermented legumes, legumes, dairy products, processed meat, and non-alcoholic beverages were associated with major phyla of the gut microbiota. A dietary pattern related to higher α-diversity (HiαDP) derived by reduced rank regression was characterized by higher intakes of fermented legumes, vegetables, seaweeds, and nuts/seeds and lower intakes of non-alcoholic beverages. The HiαDP was positively associated with several genera of Firmicutes such as Lactobacillus, Ruminococcus, and Eubacterium (all p < 0.05). Among enterotypes identified by principal coordinate analysis based on the β-diversity, the Ruminococcus enterotype had higher HiαDP scores and was strongly positively associated with intakes of vegetables, seaweeds, and nuts/seeds, compared to the two other enterotypes. We conclude that a plant- and fermented food-based diet was positively associated with some genera of Firmicutes (e.g., Lactobacillus, Ruminococcus, and Eubacterium) reflecting better gut microbial health.

Effects of Capsicum annuum supplementation on the components of metabolic syndrome: a systematic review and meta-analysis

Metabolic syndrome (MetS) has increasingly gained importance as the main risk factor for cardiovascular diseases and type II diabetes mellitus. Various natural compounds derived from plants are associated with beneficial effects on the incidence and progression of MetS. This study aimed to evaluate the effects of Capsicum annuum on factors related to MetS by assessing randomized controlled trials (written in English). We searched the online databases of PubMed, Embase, Google scholar, and Cochrane Library up to April 2020. ‘Patient/Population, Intervention, Comparison and Outcomes’ format was used to determine whether intervention with C. annuum supplementation compared with placebo supplementation had any effect on the components of MetS among participants. We considered standardized mean differences (SMD) with 95% confidence intervals (CI) as effect size measures using random-effects model. Analysis of the included 11 studies (n = 609) showed that C. annuum supplementation had significant effect on low density lipoprotein-cholesterol [SMD = − 0.39; 95% CI − 0.72, − 0.07; P = 0.02; prediction interval, − 1.28 to 0.50] and marginally significant effect on body weight [SMD = − 0.19; 95% CI − 0.40, 0.03; P = 0.09]. However, larger and well-designed clinical trials are needed to investigate the effects of C. annuum on MetS.

Metabolic tracking of isoflavones in soybean products and biosamples from healthy adults after fermented soybean consumption

Fermentation may enhance the nutritional properties of foods by increasing metabolite bioactivity or bioavailability. This study explored the effect of fermentation on isoflavone bioavailability and metabolism. Isoflavone metabolites were tracked in foods and biospecimens of healthy adults after fermented soybean (FS) or non-fermented soybean (NFS) consumption in a randomized, controlled, crossover intervention study. The change in soybean isoflavones caused by fermentation resulted in faster absorption and higher bioavailability after consumption of FS. Although the urinary level of total isoflavone metabolites was similar after the consumption of the two diets, urinary genistein 7-O-sulfate was derived as a discriminant metabolite for the FS diet by partial least squares discriminant analysis. This study suggests that an isoflavone conjugate profile might be a more appropriate marker than total isoflavone levels for discriminating between the consumption of FS and NFS diets.

Antioxidant and Anti-Inflammatory Activities in Relation to the Flavonoids Composition of Pepper (Capsicum annuum L.)

The chili pepper (Capsicum annuum L.) is a food source that is rich in flavonoids such as luteolin and apigenin. Flavonoids are known to have anti-inflammatory and antioxidant activities; however, studies on the flavonoids composition identified and the anti-inflammatory and antioxidant effects in pepper leaves (PL) and fruits (PF) are insufficient. In the present study, we investigated the antioxidant and anti-inflammatory effects in vitro, and the flavonoids contents of the PL and PF. Pepper extracts showed radical scavenging activities and ameliorated the lipopolysaccharide (LPS)-stimulated inflammatory response by decreasing nitric oxide production and interluekin-6 and tumor necrosis factor alpha levels in RAW 264.7 cells, with more effective activities noted for PL than for PF. Furthermore, PL extracts markedly inhibited the LPS-induced production of reactive oxygen species accumulation. The flavonoid profile and content of pepper were dependent on the part, with PL showing higher total flavonoids than PF. In particular, the content of luteolin glycosides in PL was twice that in PF. Thus, PL may be useful to prevent oxidative stress and inflammation-related diseases.

Agrimonia pilosa Ledeb. Ameliorates Hyperglycemia and Hepatic Steatosis in Ovariectomized Rats Fed a High-Fat Diet

Estrogen deficiency is associated with obesity, dyslipidemia, and increased insulin resistance in postmenopausal women. An efficient therapeutic agent prevents or improves postmenopausal conditions induced by estrogen deficiency. Here, we investigated the effects of aqueous Agrimonia pilosa Ledeb. extract on glucose and lipid metabolism in ovariectomized rats fed a high-fat diet (HFD). Female Sprague-Dawley rats were sham-operated or ovariectomized, and 3 weeks later were assigned to the following groups: sham-operated + HFD (S); ovariectomized + HFD (OVX); and ovariectomized + HFD with 0.5% A. pilosa aqueous extract (OVX + 0.5A) groups. Ovariectomy significantly increased body weight and dietary intake relative to the S group. However, A. pilosa treatment did not significantly affect weight gain or dietary intake. Blood triacylglycerol, total cholesterol, and low-density lipoprotein cholesterol levels tended to decrease in the A. pilosa-supplemented group. Blood glucose levels were significantly lower in the OVX + 0.5A group than those in the OVX group. Blood adiponectin and insulin concentrations increased significantly after A. pilosa treatment in the ovariectomized group. A. pilosa supplementation tended to decrease liver weights and prevented lipid accumulation. These effects correlated with reduced hepatic expression of lipogenesis-related genes (fatty acid synthase, acetyl-coenzyme A carboxylase alpha, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase). Therefore, A. pilosa may improve metabolic disorders in ovariectomized rats.

Saliva plebeia ameliorates articular carttilage degration of osteoarthritis induced rats

Osteoarthritis (OA) is the most prevalent articular disease in the elderly. The process is characterized by changes in the structure and function of the articulation, mainly due to a degeneration that takes place in the articular cartilage (AC). OA is characterized by destruction of AC and is the most common clinical syndrome of joint pain accompanied by varying degrees of functional limitation and reduced quality of life. This study was conducted to evaluate the effects of Saliva plebeia (SP) on AC degration of osteoarthritis induced rats. Salvia plebeia R.Br is an annual or biennial plant that grows in numerous countries, including Korea, China, and India. It is used as a traditional medicine to treat inflammatory diseases. The active components of SP comprise flavonoids, diterpenoids, and lignin. It is considered that appropriate treatment of SP inhibits surgical-induced OA through anti-inflammatory and AC preserve effects. In the histopathological observation, OA control rats showed marked increases of surface cartilage damages and clone formations, and decreases of chondrocytes and Safranin O stain intensities on the both femur and tibia AC. Significant increases of the Mankin scores were detected in surgical-induced OA control rats as compared with those of normal control rats. However, SP significantly improved surface cartilage damages, Mankin scores, mean femur and tibia AC thicknesses, and inflammatory cell numbers. It is expected that SP may be used as a novel potent therapeutic regime for various OA though detail mechanism studies should be needed in near future.

Effects of Allium hookeri on gut microbiome related to growth performance in young broiler chickens

Healthy food promotes beneficial bacteria in the gut microbiome. A few prebiotics act as food supplements to increase fermentation by beneficial bacteria, which enhance the host immune system and health. Allium hookeri is a healthy food with antioxidant and anti-inflammatory activities. A. hookeri is used as a feed supplement for broiler chickens to improve growth performance. Although the underlying mechanism is unknown, A. hookeri may alter the gut microbiome. In the current study, 16S rRNA sequencing has been carried out using samples obtained from the cecum of broiler chickens exposed to diets comprising different tissue types (leaf and root) and varying amounts (0.3% and 0.5%) of A. hookeri to investigate their impact on gut microbiome. The microbiome composition in the groups supplemented with A. hookeri leaf varied from that of the control group. Especially, exposure to 0.5% amounts of leaf resulted in differences in the abundance of genera compared with diets comprising 0.3% leaf. Exposure to a diet containing 0.5% A. hookeri leaf decreased the abundance of the following bacteria: Eubacterium nodatum, Marvinbryantia, Oscillospira, and Gelria. The modulation of gut microbiome by leaf supplement correlated with growth traits including body weight, bone strength, and infectious bursal disease antibody. The results demonstrate that A. hookeri may improve the health benefits of broiler chickens by altering the gut microbiome.

Dietary supplementation of Allium hookeri improved intestinal immune response on necrotic enteritis of young broiler chickens

This study was conducted to evaluate the effects of dietary Allium hookeri on intestinal immune response of young broiler chickens induced with necrotic enteritis (NE). One hundred fifty birds (1 day old) were randomly assigned to 6 groups (n =25 birds/treatment) and fed a basal diet (control) or basal diet supplemented with Allium hookeri (AH) root at 1 or 3% of the basal diet; AH1 and AH3, respectively. Birds were orally challenged with E. maxima 41A (1 × 104 cells/chicken) on day14 and followed by C. perfringens infection (1 × 109 CFU/chicken) on day18. NE-associated infection and intestinal immune response were assessed by average body weight gain, lesion score and oocyst shedding. The effect of dietary supplementation with AH on transcript levels of pro-inflammatory cytokines, tight junction and mucin protein in the jejunum were quantified by qRT-PCR. At day 20, the birds fed 3 % of AH in diet (AH3) significantly weighted more than the control group though the NE-challenge significantly reduced average body weight gain compared to the uninfected control group. Among the NE-challenged groups, gut lesion score and oocyst shedding significantly decreased in the birds given with AH (1 or 3%) compared to the control group. Gene expression levels of pro-inflammatory cytokines IL-8, IL-17α, and LITAF decreased in AH3 groups compared to the infected control group though the levels significantly increased in the NE infected groups. Interestingly AH significantly increased transcript levels of intestinal tight junction proteins and mucin at 1% of diet, not 3% of diet. These results suggest that dietary supplementation of AH can improve chicken health by controling immune response against NE and it depends on the dietary level of AH.

γ-Oryzanol suppresses COX-2 expression by inhibiting reactive oxygen species-mediated Erk1/2 and Egr-1 signaling in LPS-stimulated RAW264.7 macrophages

Cyclooxygenase (COX)-2 produces prostanoids, which contribute to inflammatory responses. Nuclear factor (NF)-κB is a key transcription factor mediating COX-2 expression. γ-Oryzanol is an active component in rice bran oil, which inhibits lipopolysaccharide (LPS)-mediated COX-2 expression by inhibiting NF-κB. However, the inhibition of COX-2 expression by γ-oryzanol independently of NF-κB is poorly understood. We found that LPS upregulated Egr-1 expression at the transcriptional level. Forced expression of Egr-1 trans-activated the Cox-2 promoter independently of NF-κB. In contrast, silencing of Egr-1 abrogated LPS-mediated COX-2 expression. LPS produced reactive oxygen species (ROS), which, in turn, induced Egr-1 expression via the Erk1/2 MAPK pathway. ROS scavenging activity of γ-oryzanol suppressed Egr-1 expression by inhibiting the Erk1/2 MAPK pathway. Our results suggest that γ-oryzanol inhibits LPS-mediated COX-2 expression by suppressing Erk1/2-mediated Egr-1 expression. This study supports that γ-oryzanol may be useful for ameliorating LPS-mediated inflammatory responses.

γ-Oryzanol-Rich Black Rice Bran Extract Enhances the Innate Immune Response

The innate immune response is an important host primary defense system against pathogens. γ-Oryzanol is one of the nutritionally important phytoceutical components in rice bran oil. The goal of this study was to investigate the effect of γ-oryzanol-rich extract from black rice bran (γORE) on the activation of the innate immune system. In this study, we show that γORE increased the expression of CD14 and Toll-like receptor 4 and enhanced the phagocytic activity of RAW264.7 macrophages. Furthermore, γORE and its active ingredient γ-oryzanol promoted the secretion of innate cytokines, interleukin-8, and CCL2, which facilitate phagocytosis by RAW264.7 cells. These findings suggest that γ-oryzanol in the γORE enhances innate immune responses.

Anti-inflammatory effects of Salvia plebeia R. Br extract in vitro and in ovalbumin-induced mouse model

BACKGROUND

Asthma is an increasing global health problem, and novel strategies to prevent or ameliorate the condition are needed. Here, the effects of 80 % ethanol extracts of Salvia plebeia R. Br. (SE) on an induced inflammatory response were investigated.

RESULTS

Salvia plebeia R. Br. inhibited production of pro-inflammatory cytokines, such as TNF-α and IL-6, as well as nitric oxide (NO) in LPS-stimulated RAW 264.7 cells. NO and pro-inflammatory cytokine production was suppressed more effectively by SE of the aerial parts (SE-A) than of the roots (SE-R) of S. plebeia. In BEAS-2B cells, both SE-A and SE-R inhibited the increase in production of the inflammatory cytokines IL-6 and IL-8. We also investigated the anti-asthmatic effects of SE in an ovalbumin (OVA)-induced BALB/c mouse model. SE-A treatment significantly reduced the number of airway eosinophils, IL-4 and IL-13 levels, mucus production, and inflammatory infiltration, as compared with the corresponding levels in the untreated, OVA-induced mice, and had similar effects to dexamethasone.

CONCLUSIONS

Salvia plebeia ethanol extract ameliorated the induced inflammatory response in RAW 264.7 and BEAS-2B cells, with more effective inhibition noted for SE-A than for SE-R. SE-A treatment was effective in improving the histopathological changes in the lungs of asthma model mice via modulation of eosinophils and Th2 cytokines. These results suggest that SE-A can be considered as a therapeutic agent that can potentially relieve asthma.

Laminin peptide YIGSR induces collagen synthesis in Hs27 human dermal fibroblasts

The dermal ECM is synthesized from fibroblasts and is primarily compromised of fibrillar collagen and elastic fibers, which support the mechanical strength and resiliency of skin, respectively. Laminin, a major glycoprotein located in the basement membrane, promotes cell adhesion, cell growth, differentiation, and migration. The laminin tyrosine-isoleucine-glycine-serine-arginine (YIGSR) peptide, corresponding to the 929-933 sequence of the β1 chain, is known to be a functional motif with effects on the inhibition of tumor metastasis, the regulation of sensory axonal response and the inhibition of angiogenesis through high affinity to the 67kDa laminin receptor. In this study, we identified a novel function of the YIGSR peptide to enhance collagen synthesis in human dermal fibroblasts. To elucidate this novel function regarding collagen synthesis, we treated human dermal fibroblasts with YIGSR peptide in both a time- and dose-dependent manner. According to subsequent experiments, we found that the YIGSR peptide strongly enhanced collagen type 1 synthesis without changing cell proliferation or cellular MMP-1 level. This YIGSR peptide-mediated collagen type 1 synthesis was modulated by FAK inhibitor and MEK inhibitor. This study clearly reveals that YIGSR peptide plays a novel function on the collagen type 1 synthesis of dermal fibroblasts and also suggests that YIGSR is a strong candidate peptide for the treatment of skin aging and wrinkles.

Black rice (Oryza sativa L.) extract attenuates hepatic steatosis in C57BL/6 J mice fed a high-fat diet via fatty acid oxidation

Background

Two major risk factors for the onset of fatty liver disease are excessive alcohol intake and obesity, the latter being associated with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to examine the effects of black rice extract (BRE) on hepatic steatosis and insulin resistance in high-fat diet-fed mice, providing a model of NAFLD.

Methods

Twenty-four mice were randomly divided into three groups (n = 8 in each group): normal fat diet (ND), high fat diet (HF), and high fat diet supplemented with 1% (w/w) BRE (HF +1% BRE). The experimental diets were fed for seven weeks.

Results

A HF induced hepatic steatosis with significant increases in the serum levels of free fatty acids (FFAs), triglyceride (TG), total cholesterol (TC), and insulin. By contrast, supplementary BRE (10 g/kg of diet) included in the HF alleviated hepatic steatosis and significantly decreased serum TG and TC levels (p < 0.01 for both). Dietary BRE also increased expression of fatty acid metabolism-related genes, including carnitine palmitoyltransferase (CPT1A), acyl-CoA oxidase (ACO), cytochrome P450 (CYP4A10), and peroxisome proliferator activated receptor (PPAR)-α (p < 0.05 for all).

Conclusions

Dietary BRE supplementation improved serum lipid profiles and significantly enhanced mRNA expression levels of fatty acid metabolism-related genes, primarily via β-oxidation and ω-oxidation in the liver. Taken together, these findings suggest that a BRE-supplemented diet could be useful in reducing the risks of hepatic steatosis and related disorders, including hyperlipidemia and hyperglycemia.

Hog millet (Panicum miliaceum L.)-supplemented diet ameliorates hyperlipidemia and hepatic lipid accumulation in C57BL/6J-ob/ob mice

Dietary intake of whole grains reduces the incidence of chronic diseases such as obesity, diabetes, cardiovascular disease, and cancer. In an earlier study, we showed that Panicum miliaceum L. extract (PME) exhibited the highest anti-lipogenic activity in 3T3-L1 cells among extracts of nine different cereal grains tested. In this study, we hypothesized that PME in the diet would lead to weight loss and augmentation of hyperlipidemia by regulating fatty acid metabolism. PME was fed to ob/ob mice at 0%, 0.5%, or 1% (w/w) for 4 weeks. After the experimental period, body weight changes, blood serum and lipid profiles, hepatic fatty acid metabolism-related gene expression, and white adipose tissue (WAT) fatty acid composition were determined. We found that the 1% PME diet, but not the 0.5%, effectively decreased body weight, liver weight, and blood triglyceride and total cholesterol levels (P < 0.05) compared to obese ob/ob mice on a normal diet. Hepatic lipogenic-related gene (PPARα, L-FABP, FAS, and SCD1) expression decreased, whereas lipolysis-related gene (CPT1) expression increased in animals fed the 1% PME diet (P < 0.05). Long chain fatty acid content and the ratio of C18:1/C18:0 fatty acids decreased significantly in adipose tissue of animals fed the 1% PME diet (P < 0.05). Serum inflammatory mediators also decreased significantly in animals fed the 1% PME diet compared to those of the ob/ob control group (P < 0.05). These results suggest that PME is useful in the chemoprevention or treatment of obesity and obesity-related disorders.

Effects of Panicum miliaceum L. extract on adipogenic transcription factors and fatty acid accumulation in 3T3-L1 adipocytes

The dietary intake of whole grains is known to reduce the incidence of chronic diseases such as obesity, diabetes, cardiovascular disease, and cancer. To investigate whether there are anti-adipogenic activities in various Korean cereals, we assessed water extracts of nine cereals. The results showed that treatment of 3T3-L1 adipocytes with Sorghum bicolor L. Moench, Setaria italica Beauvois, or Panicum miliaceum L. extract significantly inhibited adipocyte differentiation, as determined by measuring oil red-O staining, triglyceride accumulation, and glycerol 3-phosphate dehydrogenase activity. Among the nine cereals, P. miliaceum L. showed the highest anti-adipogenic activity. The effects of P. miliaceum L. on mRNA expression of peroxisome proliferator-activated receptor-γ, sterol regulatory element-binding protein 1, and the CCAAT/enhancer binding protein-α were evaluated, revealing that the extract significantly decreased the expression of these genes in a dose-dependent manner. Moreover, P. miliaceum L. extract changed the ratio of monounsaturated fatty acids to saturated fatty acids in adipocytes, which is related to biological activity and cell characteristics. These results suggest that some cereals efficiently suppress adipogenesis in 3T3-L1 adipocytes. In particular, the effect of P. miliaceum L. on adipocyte differentiation is associated with the downregulation of adipogenic genes and fatty acid accumulation in adipocytes.

Rice 1Cys-peroxiredoxin over-expressed in transgenic tobacco does not maintain dormancy but enhances antioxidant activity

Possible functions that have been proposed for the plant 1Cys-peroxiredoxin, include activity as a dormancy regulator and as an antioxidant. The transcript level of rice 1Cys-peroxiredoxin (R1C-Prx) rapidly decreased after imbibition of rice seeds, but the protein was detected for 15 days after imbibition. To investigate the function of this protein, we generated transgenic tobacco plants constitutively expressing the R1C-Prx gene. The transgenic R1C-Prx plants showed a germination frequency similar to control plants. However, the transgenic lines exhibited higher resistance against oxidative stress, suggesting that antioxidant activity may be its primary function.