Identifying high-risk factors and mitigation strategies for acrylamide formation in air-fried lotus root chips: Impact of cooking parameters, including temperature, time, presoaking, and seasoning.

This study was conducted to identify high-risk factors and mitigation strategies for acrylamide formation in air-fried lotus root chips by studying the impact of various cooking parameters, including temperature, time, presoaking, and pre-seasoning treatments. The temperature and time had a surprisingly high impact on acrylamide formation. The chips prepared at high temperatures with longer cooking times contained an extremely high acrylamide content, reaching 12,786 ng/g (e.g., 170°C/19 min). A particularly concerning discovery was that the chips with extremely high acrylamide content (up to 17 times higher than the EU benchmark level for potato chips) did not appear overcooked or taste burnt. Higher cooking temperatures required shorter cooking times to properly cook lotus root chips for consumption. A high temperature with a short cooking time (170°C/13 min) greatly benefited acrylamide reduction compared to low temperature with a long cooking time (150°C/19 min). Presoaking in a 0.1% acetic acid solution and pre-seasoning with 1% salt reduced acrylamide levels by 61% and 47%, respectively. However, presoaking in water, vinegar solution, and citric acid solution did not significantly decrease the acrylamide content in the chips. Furthermore, some seasonings significantly increased acrylamide levels (up to 7.4 times higher). For the first time, these findings underscore the high risks associated with air-frying lotus root chips without considering these factors. This study also provides proper air-frying parameters and pretreatment strategies for minimizing acrylamide formation in air-fried lotus chips.

Lactococcus lactis KF140 Reduces Dietary Absorption of Nε - (Carboxymethyl)lysine in Rats and Humans via ß-Galactosidase Activity.

Background and Aims: Excessive intake of advanced glycation end products (AGEs), which are formed in foods cooked at high temperatures for long periods of time, has negative health effects, such as inflammatory responses and oxidative stress. Nε-(Carboxymethyl)lysine (CML) is one of the major dietary AGEs. Given their generally recognized as safe status and probiotic functionalities, lactic acid bacteria may be ideal supplements for blocking intestinal absorption of food toxicants. However, the protective effects of lactic acid bacteria against dietary AGEs have not been fully elucidated. Materials and Methods: We investigated the effect of treatment with Lactococcus lactis KF140 (LL-KF140), which was isolated from kimchi, on the levels and toxicokinetics of CML. The CML reduction efficacies of the Lactococcus lactis KF140 (LL-KF140), which was isolated from kimchi, were conducted by in vitro test for reducing CML concentration of the casein-lactose reaction product (CLRP) and in vivo test for reducing serum CML level of LL-KF140 administered rats at 2.0 × 108 CFU/kg for14 days. In addition, 12 volunteers consuming LL-KF140 at 2.0 × 109 CFU/1.5 g for 26 days were determined blood CML concentration and compared with that before intake a Parmesan cheese. Results: Administration of LL-KF140 reduced serum CML levels and hepatic CML absorption in rats that were fed a CML-enriched product. In a human trial, the intake of LL-KF140 prevented increases in the serum levels of CML and alanine aminotransferase after consumption of a CML-rich cheese. LL-KF140 was determined to presence in feces through metagenome analysis. Furthermore, ß-galactosidase, one of the L. lactis-produced enzymes, inhibited the absorption of CML and reduced the levels of this AGE, which suggests an indirect inhibitory effect of LL-KF140. This study is the first to demonstrate that an L. lactis strain and its related enzyme contribute to the reduction of dietary absorption of CML.

Codonopsis lanceolata Contributes to Ca2+ Homeostasis by Mediating SOCE and PLC/IP3 Pathways in Vascular Endothelial and Smooth Muscle Cells.

Codonopsis lanceolata has been widely used as an anti-inflammatory and anti-lipogenic agent in traditional medicine. Recently, C. lanceolata was reported to prevent hypertension by improving vascular function. This study evaluated the effects of C. lanceolata and its major component lancemaside A on cytosolic calcium concentration in vascular endothelial cells and vascular smooth muscle cells. Cytosolic calcium concentration was measured using fura-2 AM fluorescence. C. lanceolata or lancemaside A increased the cytosolic calcium concentration by releasing Ca2+ from the endoplasmic reticulum and sarcoplasmic reticulum and by Ca2+ entry into endothelial cells and vascular smooth muscle cells from extracellular sources. The C. lanceolata- and lancemaside A-induced cytosolic calcium concentration increases were significantly inhibited by lanthanum, an inhibitor of non-selective cation channels, in both endothelial cells and vascular smooth muscle cells. Moreover, C. lanceolata and lancemaside A significantly inhibited store-operated Ca2+ entry under pathological extracellular Ca2+ levels. In Ca2+-free extracellular fluid, increases in the cytosolic calcium concentration induced by C. lanceolata or lancemaside A were significantly inhibited by U73122, an inhibitor of phospholipase C, and 2-APB, an inositol 1,4,5-trisphosphate receptor antagonist. In addition, dantrolene treatment, which inhibits Ca2+ release through ryanodine receptor channels, also inhibited C. lanceolata- or lancemaside A-induced increases in the cytosolic calcium concentration through the phospholipase C/inositol 1,4,5-trisphosphate pathway. These results suggest that C. lanceolata and lancemaside A increase the cytosolic calcium concentration through the non-selective cation channels and phospholipase C/inositol 1,4,5-trisphosphate pathways under physiological conditions and inhibit store-operated Ca2+ entry under pathological conditions in endothelial cells and vascular smooth muscle cells. C. lanceolata or lancemaside A can protect endothelial cells and vascular smooth muscle cells by maintaining cytosolic calcium concentration homeostasis, suggesting possible applications for these materials in diets for preventing vascular damage.

Beneficial effects of Codonopsis lanceolata extract on systolic blood pressure levels in prehypertensive adults: A double-blind, randomized controlled trial.

Codonopsis lanceolata (CL) extract was shown to have antihypertensive effects in hypertensive rats. This randomized controlled trial was designed to investigate the ability of CL extract to prevent hypertension (HTN) in prehypertensive subjects. Eighty subjects aged 19-60 years with a systolic blood pressure (BP) of 120-139 mmHg and a diastolic BP of 80-89 mmHg were recruited over 3 months. Subjects were randomized 1:1 to a CL group and a placebo (PL) group and administered CL extract and starch, respectively, for 6 weeks. (BP) was measured and blood sampled at baseline and at the end of the trial. Relative to baseline, systolic BP was significantly decreased, and catalase activity was significantly increased following CL treatment in both the elevated systolic BP and stage 1 HTN subgroups. In the elevated systolic BP subgroup, serum nitrite concentration relative to baseline was significantly increased in CL compared to PL treated subjects (p = .038). In subjects with stage 1 HTN, high sensitivity C-reactive protein (p = .020) and malondialdehyde (p = .039) showed significantly greater reductions from baseline in the CL than in the PL group. In summary, CL was effective in preventing endothelial dysfunction, inflammation, and lipid peroxidation in prehypertensive subjects, with these effects differing according to baseline systolic BP levels.

ERK/Nrf2 pathway activation by caffeic acid in HepG2 cells alleviates its hepatocellular damage caused by t-butylhydroperoxide-induced oxidative stress.

BACKGROUND: Several studies have found that caffeic acid (CA), a well-known phytochemical, displays important antioxidant and anti-cancer activities. However, no evidence exists on the protective effect and its mechanisms that CA treatment alone has against oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells. METHODS: Hepatoprotective activities such as cell viability, mRNA expression, and report gene assay were measured using HepG2 cell. Three types of genes and proteins related with detoxification in liver were used for measuring the hepatoprotective effects. Statistical analysis was performed using one-way ANOVA test and differences among groups were evaluated by Tukey's studentized range tests. RESULTS: The present study indicate that treatment with CA up-regulates heme oxygenase-1 (HO-1) and glutamate-cysteine ligase (GCL) mRNA and protein expressions in a CA-dose-dependent manner. In addition, translocation of nuclear factor-E2 p45-related factor (Nrf2) from the cytoplasm to the nucleus and phosphorylation of extracellular signal-regulated kinase, ERK and c-Jun N-terminal kinase, JNK which have been shown to be involved in mitogen-activated protein kinases, MAPKs are significantly enhanced by CA treatment. Furthermore, in cell nuclei, CA enhances the 5'-flanking regulatory region of human antioxidant response element (ARE) and activates the ARE binding site. CONCLUSION: Therefore, CA proved to be a stimulant of the expression of detoxification enzymes such as HO-1, GCLC, and GCLM through the ERK/Nrf2 pathway, and it may be an effective chemoprotective agent for protecting liver damage against oxidative damage.

Lancemaside A, a major triterpene saponin of Codonopsis lanceolata enhances regulation of nitric oxide synthesis via eNOS activation.

BACKGROUND: Many studies on the effect of saponin-rich Codonopsis lanceolata as a bioactive source for improving physical health have been performed. C. lanceolata contains triterpenoid saponins, including lancemasides. These saponins are known to be particularly involved in the regulation of blood pressure or hypertension. This study investigated whether lancemaside A (LA), a major triterpenoid saponin from C. lanceolata, regulates nitric oxide (NO) production via the activation of endothelial NO synthase (eNOS) in human umbilical vein endothelial cells. METHODS: Upon separation with petroleum ether, ethyl acetate, and n-butanol, LA was found to be abundant in the n-butanol-soluble portion. For further purification of LA, HPLC was performed to collect fraction, and LA was identified using analysis of LC/MSMS and 13C-NMR values. In in vitro, the effects of LA on NO release mechanism in HUVECs were investigated by Griess assay, quantitative real-time reverse-transcription PCR, and Western blotting. RESULTS: Our results showed that NO production was efficiently improved by treatment with LA in a dose-dependent manner. In addition, the LA treatment resulted in extensive recovery of the NO production suppressed by the eNOS inhibitor, L-NAME, compared with that in the control group. Additionally, the level of eNOS mRNA was increased by this treatment in a dose-dependent manner. These results suggested that LA is an inducer of NO synthesis via eNOS mRNA expression. Also, the study indicated that LA is involved in activating the PI3K/Akt/eNOS signaling pathway. CONCLUSION: These results suggested that LA is an inducer of NO synthesis via eNOS mRNA expression. Also, the study indicated that LA is involved in activating the PI3K/Akt/eNOS signaling pathway. These findings suggest the value of using LA as a component of functional foods and natural pharmaceuticals.

Codonopsis lanceolata extract prevents hypertension in rats.

BACKGROUND: Codonopsis lanceolata, a plant with antioxidant, anti-cancer, anti-inflammatory and blood lipid improving effects, has been widely used as a therapeutic agent in traditional medicine. PURPOSE: The present study investigated the ability of an ethanol extract of Codonopsis lanceolata (ECL) to prevent hypertension in hypertensive rats. METHODS: Rats were orally administered daily doses of 0 mg/kg, 200 mg/kg and 400 mg/kg ECL for 3 weeks. As a positive control, rats were orally administered 10 mg/kg/day nifedipine. Hypertension was induced by immobilization stress for 2 h/day and by administration of 0.8 mg/kg/day nicotine for 3 weeks, followed by injection of 3 mg/kg nicotine on the day of sacrifice. Blood pressure and heart rate were measured using a volume pressure recording system. Vasoconstriction and vasodilation of aortic cross sections were measured with a physiological recorder. Neutrophil counts in bronchoalveolar lavage fluid were estimated with an automated cell counter. RESULTS: Treatment with both dosages of ECL significantly reduced systolic blood pressure (SBP) in hypertensive rats. Both doses of ECL tended to increase ACh- and SNP-induced vascular relaxation in hypertensive rats. Treatment with 200 mg/kg ECL significantly reduced neutrophil in hypertensive rats. CONCLUSIONS: These results suggest that ECL is effective in reducing SBP and inflammation in hypertensive conditions.

Development and Method Validation of Analysis of Urushiol in Sumac and Food Ingredients in Korea.

This study developed an analytical method to determine the urushiol content in sap and several foods. The full process for urushiol analysis consists of extraction, trimethylsilyl silylation, analysis, and identification via GC-MS, with each step optimized to attain the required accuracy and precision. Urushiol was separated from sap via liquid-liquid extraction and was derivatized via silylation. The components were analyzed using a polar capillary column and identified using GC-MS. The deviations of relative retention times and retention time windows were within 0.001 and 0.02 min, which satisfied the criteria of 0.06 and 0.03 min, respectively. The response of the urushiol standards tested was found to be linear in the investigated concentration range, with a correlation coefficient of 0.998. The LODs were between 1.74 and 2.67 µg/mL.

Protective effects of chebulic acid on alveolar epithelial damage induced by urban particulate matter.

BACKGROUND: Chebulic acid (CA) isolated from T. chebula, which has been reported for treating asthma, as a potent anti-oxidant resources. Exposure to ambient urban particulate matter (UPM) considered as a risk for cardiopulmonary vascular dysfunction. To investigate the protective effect of CA against UPM-mediated collapse of the pulmonary alveolar epithelial (PAE) cell (NCI-H441), barrier integrity parameters, and their elements were evaluated in PAE. METHODS: CA was acquired from the laboratory previous reports. UPM was obtained from the National Institutes of Standards and Technology, and these were collected in St. Louis, MO, over a 24-month period and used as a standard reference. To confirm the protection of PAE barrier integrity, paracellular permeability and the junctional molecules were estimated with determination of transepithelial electrical resistance, Western Blotting, RT-PCR, and fluorescent staining. RESULTS: UPM aggravated the generation of reactive oxygen species (ROS) in PAE and also decreased mRNA and protein levels of junction molecules and barrier integrity in NCI-H441. However, CA repressed the ROS in PAE, also improved barrier integrity by protecting the junctional parameters in NCI-H411. CONCLUSIONS: These data showed that CA resulted in decreased UPM-induced ROS formation, and the protected the integrity of the tight junctions against UPM exposure to PAE barrier.

Rice bran constituents: immunomodulatory and therapeutic activities.

Rice bran, one of the most abundant and valuable byproducts produced during the rice milling process, is of steadily growing interest in recent years due to its potential health benefits. Evidence is rapidly accumulating for the beneficial effects of nutraceuticals. However, the potential benefits of rice bran are found in several of its bioactive ingredients including oils, polysaccharides, proteins, and micronutrients. In addition, a significant advantage of rice bran is that it contains more than 100 antioxidants and several categories of bioactive phytonutrients, such as polyphenols, phytosterols, tocotrienols, γ-oryzanol, B vitamins, minerals, and trace minerals. As an immunomodulator, rice bran has beneficial constituents such as polysaccharides, proteins, and oils. Numerous studies also reported that potent antioxidants in rice bran included immune system enhancing compounds, such as phytosterols, polysaccharides, minerals and trace minerals including magnesium, selenium, zinc, vitamin E, omega-3 fatty acids and several other phytonutrients. We believe that this review will be a valuable resource for more studies on rice barn as a dietary source.

Plantamajoside from Plantago asiatica modulates human umbilical vein endothelial cell dysfunction by glyceraldehyde-induced AGEs via MAPK/NF-κB.

BACKGROUND: Plantago asiatica has been traditionally used for traditional medicine around East Asia. Plantamajoside (PM), which is isolated from this plant, is known for biological properties including anti-inflammation and antioxidant activity. To demonstrate the biological activity of PM against endothelial dysfunction induced by advanced glycation end-products (AGEs), a cellular inflammatory mechanism system was evaluated in human umbilical vein endothelial cells (HUVECs). METHODS: We obtained PM through previous research in our laboratory. We formed the AGEs from bovine serum albumin with glyceraldehyde in the dark for seven days. To confirm the modulation of the inflammatory mechanism in endothelial dysfunction, we quantified the various pro-inflammatory cytokines and endothelial dysfunction-related proteins in the HUVECs with Western blotting and with real-time and quantitative real-time polymerase chain reactions. RESULTS: Co-treatment with PM and AGEs significantly suppressed inflammatory cytokines and adhesion molecule expression. Moreover, the PM treatment for down-regulated inflammatory signals and blocked monocyte adhesion on the HUVECs. CONCLUSIONS: Theses results demonstrated that PM, as a potential natural compound, protects AGE-induced endothelial cells against inflammatory cellular dysfunction.

Microbiological characterization and functionality of set-type yogurt fermented with potential prebiotic substrates Cudrania tricuspidata and Morus alba L. leaf extracts.

The objective of this study was to investigate the effect of 2 plant leaf extracts on fermentation mechanisms and health-promoting activities and their potential as a nutraceutical prebiotics ingredient for application in dairy products. The individual active phenolic compounds in the plant extract-supplemented milk and yogurts were also identified. Compared with control fermentation, the plant extracts significantly increased the growth and acidification rate of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. In particular, plant extract components, including monosaccharides, formic acid, and hydroxycinnamic acid, such as neo-chlorogenic, chlorogenic, and caffeic acid, together play a stimulatory role and cause this beneficial effect on the growth of yogurt culture bacteria through fermentation. In addition, supplementation with the plant extracts enhanced antioxidant activities with increased total phenolic contents, especially the highest antioxidant activity was observed in yogurt supplemented with Cudrania tricuspidata leaf extract.

Improved functionality of fermented milk is mediated by the synbiotic interaction between Cudrania tricuspidata leaf extract and Lactobacillus gasseri strains.

This study was designed to investigate the cooperative effect of selected Lactobacillus gasseri strains and Cudrania tricuspidata (CT) leaf extract in enhancing the health-promoting activities of fermented milk. Addition of CT increased total bacterial counts and proteolysis during fermentation of milk with L. gasseri strains. Antioxidant capacities were determined by measuring the ABTS, DPPH, and peroxyl radical scavenging activities and ferric reducing power. The antioxidant capacity of CT-supplemented milk was greater than that of milk without supplementation; moreover, the antioxidant activity of CT-supplemented milk was synergistically improved by fermentation with L. gasseri strains. In particular, CT-supplemented milk fermented by L. gasseri 505 showed the highest antioxidant activity. The phenolic compounds in CT, such as neo-chlorogenic, chlorogenic, and caffeic acid, were metabolized during fermentation with L. gasseri strains, and 3,4-dihydroxy-hydrocinnamic acid was produced as a fermentation metabolite. Moreover, the liberation of bioactive peptides of fermented milk was increased by the proteolytic activity of L. gasseri strains. In particular, six peptides, which were mainly derived from ß-casein, were newly identified in this study. These findings suggest that L. gasseri strains metabolize the phenolic acids in the CT and the bioactive peptides released through this interaction improve the antioxidant activity of the fermented milk.

Immunomodulatory Effects of Nontoxic Glycoprotein Fraction Isolated from Rice Bran.

Rice bran, a by-product of brown rice milling, is a rich source of dietary fiber and protein, and its usage as a functional food is expected to increase. In this study, immunomodulatory effects of glycoprotein obtained from rice bran were studied in normal mice and mouse models of cyclophosphamide-induced immunosuppression. We prepared glycoprotein from rice bran by using ammonium precipitation and anion chromatography techniques. Different doses of glycoprotein from rice bran (10, 25, and 50 mg/kg) were administered orally for 28 days. On day 21, cyclophosphamide at a dose of 100 mg/kg was administered intraperitoneally. Glycoprotein from rice bran showed a significant dose-dependent restoration of the spleen index and white blood cell count in the immunocompromised mice. Glycoprotein from rice bran affected the immunomodulatory function by inducing the proliferation of splenic lymphocytes, which produce potential T and B cells. Moreover, it prevented cyclophosphamide-induced damage of Th1-type immunomodulatory function through enhanced secretion of Th1-type cytokines (interferon-γ and interleukin-12). These results indicate that glycoprotein from rice bran significantly recovered cyclophosphamide-induced immunosuppression. Based on these data, it was concluded that glycoprotein from rice bran is a potent immunomodulator and can be developed to recover the immunity of immunocompromised individuals.

Pheophorbide a from Capsosiphon fulvescens Inhibits Advanced Glycation End Products Mediated Endothelial Dysfunction.

During hyperglycemia, the first step toward the formation of advanced glycation end products is the nonenzymatic glycation between the carbonyl group of a sugar and the primary amino group of a protein. Advanced glycation end products are then produced through more complex reactions. Reactive oxygen species derived from advanced glycation end products may play a key role in inflammation of the endothelium, leading to the complications seen in diabetes. Glycolaldehyde-induced advanced glycation end products have been reported to express proinflammatory cytokines, such as tumor necrosis factor-α and interleukin-1ß. This study focused on Capsosiphon fulvescens, a Capsosiphonaceae type of green algae that has shown potential as a functional food material. Pheophorbide a, an anti-glycation compound, was isolated from C. fulvescens by extraction using a mixture of ethanol and water, followed by column fractionation of the resulting extract. The compound separated from C. fulvescens was identified by means of high-performance liquid chromatography combined with mass spectrometry. Pheophorbide a showed scavenging activity of the intracellular reactive oxygen species as well as monocyte adhesiveness inhibitory activity on the human myelomonocytic cell line (THP-1) and human umbilical vein endothelial cells cocultivation system. The mRNA levels of inflammation-related genes such as monocyte chemoattractant protein-1 and interleukin-6 were significantly decreased by pheophorbide a, and advanced glycation end products-stimulated tumor necrosis factor-α and interleukin-1ß were downregulated as well. These results indicate that pheophorbide a has significant reactive oxygen species-scavenging activity, monocyte adhesive inhibitory activity, and downregulatory activity of cytokines related to inflammation affecting the endothelium. Pheophorbide a could therefore be a promising candidate for modulating endothelial cell dysfunction.

Dead Nano-Sized Lactobacillus plantarum Inhibits Azoxymethane/Dextran Sulfate Sodium-Induced Colon Cancer in Balb/c Mice.

The chemopreventive effects of dead nano-sized Lactobacillus plantarum (nLp) on colon carcinogenesis, induced by dextran sulfate sodium and azoxymethane, were evaluated using Balb/c mice and compared with the effects of pure live L. plantarum (pLp). nLp is a dead shrunken form of L. plantarum derived from kimchi and has a particle size of 0.5-1.0 µm. Animals fed nLp showed less weight loss, longer colons, lower colon weight/length ratios, and fewer colonic tumors compared with pLp. In addition, the administration of nLp significantly reduced the expression of inflammatory markers, mediated the expression of cell cycle and apoptotic markers in colon tissues, and elevated fecal IgA levels more than pLp. Accordingly, the present study shows that the anticolorectal cancer activities of nLp are greater than those of pLp and suggests this is due to the suppression of inflammation, the induction of cell cycle arrest and apoptosis, and enhanced IgA secretion.

Effect of Nanometric Lactobacillus plantarum in Kimchi on Dextran Sulfate Sodium-Induced Colitis in Mice.

Nanometric Lactobacillus plantarum (nLp) is a processed form of Lab. plantarum derived from kimchi and is 0.5-1.0 µm in size. This study was undertaken to determine the effect of nLp and kimchi plus nLp (K-nLp) on a dextran sulfate sodium (DSS)-induced mouse model of colitis. Animals fed nLp or K-nLp had longer colons, but lower colon weights per unit length than DSS controls. In addition, nLp- or K-nLp-fed animals showed lower levels of proinflammatory cytokines and inflammatory genes in serum and in colon tissues, lower populations of total bacteria, but higher populations of lactic acid bacteria in feces, and lower activities of fecal ß-glucosidase and ß-glucuronidase. Furthermore, these suppressive activities of nLp on colitis were equivalent to or higher than those of naive Lab. plantarum. Consequently, nLp was found to exhibit anticolitic effects, and the addition of nLp to kimchi was found to enhance the protective activity of kimchi against DSS-induced colitis. These results suggest that nLp might be an effective substitute for live probiotics and be useful as a functional ingredient with the anticolitic activity by the probiotic and food processing industries.

Genipin, a cross-linking agent, promotes odontogenic differentiation of human dental pulp cells.

INTRODUCTION: The aim of this study was to investigate the effects of genipin, a natural collagen cross-linking agent, on odontogenic differentiation of human dental pulp cells (hDPCs) because the mechanical properties of collagen allow it to serve as a scaffold for engineering of pulp-dentin complex. Furthermore, the role of extracellular signal-regulated kinase (ERK) was investigated as a mediator of the differentiation. METHODS: The odontogenic differentiation was analyzed by alkaline phosphatase activity, real time-polymerase chain reaction, Western blotting, and alizarin red S staining. The morphologic features of hDPCs cultured in genipin-treated collagen were evaluated by scanning electron microscopy. For the assessment of mechanical properties of collagen treated with genipin, the surface roughness and compressive strength were measured. RESULTS: Alkaline phosphatase activity, the expression of odontogenic markers, and mineralized nodule formation increased in the genipin-treated group. Genipin also activated ERK, and treatment with ERK inhibitor blocked the expression of the markers. The cells cultured in genipin-treated collagen spread across the substrate and attached in close proximity to one another. The proliferation and differentiation of hDPCs cultured in genipin-treated collagen were facilitated. The mechanical properties of collagen, such as surface roughness and compressive strength, were increased by treatment with genipin. CONCLUSIONS: Our results show that genipin promotes odontogenic differentiation of hDPCs via the ERK signaling pathway. Furthermore, the enhanced mechanical properties of the collagen scaffold induced by genipin may play important roles in cell fate. Consequently, the application of genipin might be a new strategy for dentin-pulp complex regeneration.

5-α Reductase inhibitory effect and astringent activity of green apple rind extract on human keratinocytes and fibroblast cells.

Unripe green apples contain condensed tannins at 10 times higher levels than ripe apples. Tannin not only has strong antioxidant activity, but also an astringent property. In this study, we investigated the effects of green apple rind (GAR) extracts in reducing facial pores and sebum secretion. Among the GAR extracts, the 70% ethanol GAR extract showed the highest antioxidant activity and tannin content. Hence, it was further fractionated with different solvents. Among these rind solvent fractions, the ethyl acetate fraction of the extract (GAR-E) showed astringent activity. Additionally, it exhibited inhibitory effects on 5-α reductase, and induced type 1 collagen and involucrin synthesis. These results suggest that GAR-E can be applied in cosmetics to reduce facial pore size and sebum secretion.