A Shapable Alginate Hydrogel Resolving the Conflicts between Multifunctionality and Fabrication Simplicity.

Alginate is a naturally derived biocompatible polymer widely used as a drug or food adjuvant. However, its usage as a biofunctional material has been confounded by the lack of shapable strategies. In this study, we report an easily applied ionic cross-linking strategy for fabricating shapable multifunctional SA-Ca(II) hydrogels employing the process of regulated diffusion. The fabrication proceeds in neutral solutions under ambient conditions. The obtained SA-Ca(II) hydrogel presents tunable moduli ranging from 4 to 30 kPa, resembling a series of human tissues. The tunable mechanical strength provides differentiation signals for stem cell polarization. The hydrogel film can lift a weight of 10 kg. The hydrogel can be prepared into various shapes and remains stable over one year upon rinsing in deionized water, but rapidly degrades in alginate lyase solutions. Subcutaneously embedded SA-Ca(II) hydrogels in mice show high biocompatibility and degrade over 4 weeks accompanied by hair follicle regeneration. Wearable protections as well as stimuli-responsive electronic circuits are then achieved, which not only protect the model body against high-temperature environments but also show warning signals when the protection loses effectiveness because of high temperatures. Overall, these results demonstrate that our SA-Ca(II) hydrogel offers appealing comprehensive functionalities from multifaceted perspectives, including mechanical strength, economic and environmental considerations, transparency, forming capability, biocompatibility, and conductivity.

Simultaneous Determination of Multiple Reactive Carbonyl Species in High Fat Diet-Induced Metabolic Disordered Mice and the Inhibitory Effects of Rosemary on Carbonyl Stress.

As potential endogenous biomarkers, reactive carbonyl species (RCS) have gained abundant attention for monitoring oxidative and carbonyl stress. However, there is no accurate method to evaluate multiple RCS in biological samples. In this study, a 2,4-dinitrophenylhydrazine (DNPH) derivatization-based LC-MS method was developed and validated to quantitate eight RCS: malondialdehyde (MDA), acrolein (ACR), 4-hydroxy-2-nonenal (4-HNE), 4-oxo-2-nonenal (4-ONE), methylglyoxal (MGO), glyoxal (GO), 3-deoxyglucosone (3-DG), and 2-keto-d-glucose (2-Keto). Subsequently, the method was applied to assess the RCS in low fat (LF), high fat (HF), and HF plus rosemary extract (RE) diet-fed mouse samples. The quantitative results on RCS levels indicated that the HF diet significantly increased the total RCS levels in mouse urine, plasma, and kidney with an average rate of 280.69%, 153.87%, and 61.30%, respectively. The RE administration significantly inhibited the elevated RCS levels induced by the HF diet, especially for MDA, 4-ONE, 4-HNE, and 2-Keto in mouse plasma, and ACR and 2-Keto in mouse kidney. This is the first study to simultaneously measure eight RCS in biological samples and demonstrate that RE was able to eliminate the accumulation of the HF diet-induced RCS.

Dietary Genistein Reduces Methylglyoxal and Advanced Glycation End Product Accumulation in Obese Mice Treated with High-Fat Diet.

Our previous study has found that dietary genistein could ameliorate high-fat diet (HFD)-induced obesity and especially lower methylglyoxal (MGO) and advanced glycation end product (AGE) accumulation in healthy mice exposed to genistein and HFD. However, it is still unclear whether dietary genistein intervention has a similar beneficial effect in obese mice. In this study, the mice were induced with obesity after being fed a HFD for nine weeks before being administered with two doses of genistein, 0.1% (G 0.1) and 0.2% (G 0.2), in the HFD for additional 19 weeks. After 19 week treatment, genistein supplementation reduced body and liver weights, plasma and liver MGO levels, and kidney AGE levels in mice. Mechanistically, genistein upregulated the expressions of glyoxalase I and II and aldose reductase to detoxify MGO, and genistein and its microbial metabolites, dihydrogenistein and 6'-hydroxy-O-demethylangolensin, were able to trap endogenous MGO via formation of MGO conjugates. Taken together, our results provide novel insights into the antiobesity and antiglycation roles of dietary genistein in obese subjects.

Dietary Genistein Inhibits Methylglyoxal-Induced Advanced Glycation End Product Formation in Mice Fed a High-Fat Diet.

BACKGROUND: Methylglyoxal (MGO), an important precursor of advanced glycation end products (AGEs), circulates at high concentrations in diabetic patients' blood and plays an important role in the pathogenesis of diabetes and other chronic diseases. OBJECTIVES: The aim of this study was to determine whether dietary genistein can prevent indicators of metabolic syndrome (MetS) induced by a very-high-fat (VHF) diet or a high-fat (HF) diet plus exogenous MGO, and the accumulation of MGO and AGEs in mice. METHODS: Male, 6-wk-old C57BL/6J mice (n = 15) were fed a low-fat (LF) diet (10% fat energy) or a VHF diet (60% fat energy) alone or including 0.25% genistein (VHF-G) for 16 wk in study 1. In study 2, 75 similar mice were fed the LF diet (LF) or the HF diet alone (HF) or in combination with up to 0.2% MGO in water (HFM) and 0.067% (HFM-GL) or 0.2% (HFM-GH) dietary genistein for 18 wk. Anthropometric and metabolic data were obtained in both studies to determine the effects of MGO and genistein on variables indicative of MetS. RESULTS: Body weight gain, fat deposits, dyslipidemia, hyperglycemia, and fatty liver were ameliorated by dietary genistein in both studies. The plasma MGO concentration in VHF-G mice was 52% lower than that in VHF mice. Moreover, the AGE concentrations in plasma, liver, and kidney of VHF-G mice were 73%, 52%, and 49%, respectively, lower than in the VHF group (study 1). Similarly, the concentrations of plasma MGO and AGE in plasma, liver, and kidney of HFM-GH mice were 33.5%, 49%, 69%, and 54% lower than in HFM mice (study 2). Genistein inhibited AGE formation by trapping MGO to form adducts and upregulating the expressions of glyoxalase I and II and aldose reductase in liver and kidney to detoxify MGO in both studies. CONCLUSIONS: Our data demonstrate for the first time that genistein significantly lowers MGO and AGE concentrations in 2 mouse MetS models via multiple pathways.

Microbiota facilitates the formation of the aminated metabolite of green tea polyphenol (-)-epigallocatechin-3-gallate which trap deleterious reactive endogenous metabolites.

The in vivo mechanism of tea polyphenol-mediated prevention of many chronic diseases is still largely unknown. Studies have shown that accumulation of toxic reactive cellular metabolites, such as ammonia and reactive carbonyl species (RCS), is one of the causing factors to the development of many chronic diseases. In this study, we investigated the in vivo interaction between (-)-epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in tea leaves, and ammonia and RCS. We found that EGCG could be oxidized to EGCG quinone in mice, and then rapidly react with ammonia to generate the aminated EGCG metabolite, 4'-NH2-EGCG. Both EGCG and its aminated metabolite could further scavenge RCS, such as methylglyoxal (MGO), malondialdehyde (MDA), and trans-4-hydroxy-2-nonenal (4-HNE), to produce the RCS conjugates of EGCG and the aminated EGCG. Both the aminated and the RCS conjugated metabolites of EGCG were detected in human after drinking four cups of green tea per day. By comparing the levels of the aminated and the RCS conjugated metabolites in EGCG exposed germ-free (GF) mice and specific-pathogen-free (SPF) mice, we demonstrated that gut microbiota facilitate the formation of the aminated metabolite of EGCG, the RCS conjugates of EGCG, and the RCS conjugates of the aminated EGCG. By comparing the trapping capacities of EGCG and its aminated metabolite under aerobic and anaerobic conditions, we found that oxygen is not essential for the trapping of reactive species by EGCG and 4'-NH2-EGCG suggesting that EGCG and its aminated metabolite could scavenge RCS in the GI track and in the circulation system. Altogether, this study provides in vivo evidences that EGCG has the capacity to scavenge toxic reactive metabolic wastes. This finding opens a new window to understand the underlying mechanisms by which drinking tea could prevent the development of chronic diseases.

Steroidal Saponins in Oat Bran.

Saponins are one type of widespread defense compound in the plant kingdom and have been exploited for the production of lead compounds with diverse pharmacological properties in drug discovery. Oats contain two unique steroidal saponins, avenacoside A, 1, and avenacoside B, 2. However, the chemical composition, the levels of these saponins in commercial oat products, and their health effects are still largely unknown. In this study, we directly purified 5 steroidal saponins (1-5) from a methanol extract of oat bran, characterized their structures by analyzing their MS and NMR spectra, and also tentatively identified 11 steroidal saponins (6-16) on the basis of their tandem mass spectra (MS(n), n = 2-3). Among the five purified saponins, 5 is a new compound and 4 is purified from oats for the first time. Using HPLC-MS techniques, a complete profile of oat steroidal saponins was determined, and the contents of the two primary steroidal saponins, 1 and 2, were quantitated in 15 different commercial oat products. The total levels of these two saponins vary from 49.6 to 443.0 mg/kg, and oat bran or oatmeal has higher levels of these two saponins than cold oat cereal. Furthermore, our results on the inhibitory effects of 1 and 2 against the growth of human colon cancer cells HCT-116 and HT-29 showed that both had weak activity, with 2 being more active than 1.

Carnosic acid as a major bioactive component in rosemary extract ameliorates high-fat-diet-induced obesity and metabolic syndrome in mice.

In this study, we investigated the preventive effects of carnosic acid (CA) as a major bioactive component in rosemary extract (RE) on high-fat-diet-induced obesity and metabolic syndrome in mice. The mice were given a low-fat diet, a high-fat diet or a high-fat diet supplemented with either 0.14% or 0.28% (w/w) CA-enriched RE (containing 80% CA, RE#1L and RE#1H), or 0.5% (w/w) RE (containing 45% CA, RE#2), for a period of 16 weeks. There was the same CA content in the RE#1H and RE#2 diets and half of this amount in the RE#1L diet. The dietary RE supplementation significantly reduced body weight gain, percent of fat, plasma ALT, AST, glucose, insulin levels, liver weight, liver triglyceride, and free fatty acid levels in comparison with the mice fed with a HF diet without RE treatment. RE administration also decreased the levels of plasma and liver malondialdehyde, advanced glycation end products (AGEs), and the liver expression of receptor for AGE (RAGE) in comparison with those for mice of the HF group. Histological analyses of liver samples showed decreased lipid accumulation in hepatocytes in mice administrated with RE in comparison with that of HF-diet-fed mice. Meanwhile, RE administration enhanced fecal lipid excretion to inhibit lipid absorption and increased the liver GSH/GSSG ratio to perform antioxidant activity compared with HF group. Our results demonstrate that rosemary is a promising dietary agent to reduce the risk of obesity and metabolic syndrome.

Tea Flavanols Block Advanced Glycation of Lens Crystallins Induced by Dehydroascorbic Acid.

Growing evidence has shown that ascorbic acid (ASA) can contribute to protein glycation and the formation of advanced glycation end products (AGEs), especially in the lens. The mechanism by which ascorbic acid can cause protein glycation probably originates from its oxidized form, dehydroascorbic acid (DASA), which is a reactive dicarbonyl species. In the present study, we demonstrated for the first time that four tea flavanols, (-)-epigallocatechin 3-O-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin 3-O-gallate (ECG), and (-)-epicatechin (EC), could significantly trap DASA and consequently form 6C- or 8C-ascorbyl conjugates. Among these four flavanols, EGCG exerted the strongest trapping efficacy by capturing approximate 80% of DASA within 60 min. We successfully purified and identified seven 6C- or 8C-ascorbyl conjugates of flavanols from the chemical reaction between tea flavanols and DASA under slightly basic conditions. Of which, five ascorbyl conjugates, EGCGDASA-2, EGCDASA-2, ECGDASA-1, ECGDASA-2 and ECDASA-1, were recognized as novel compounds. The NMR data showed that positions 6 and 8 of the ring A of flavanols were the major active sites for trapping DASA. We further demonstrated that tea flavanols could effectively inhibit the formation of DASA-induced AGEs via trapping DASA in the bovine lens crystallin-DASA assay. In this assay, 8C-ascorbyl conjugates of flavanols were detected as the major adducts using LC-MS. This study suggests that daily consumption of beverages containing tea flavanols may prevent protein glycation in the lens induced by ascorbic acid and its oxidized products.

Preservation of hepatocyte nuclear factor-4α contributes to the beneficial effect of dietary medium chain triglyceride on alcohol-induced hepatic lipid dyshomeostasis in rats.

BACKGROUND: Alcohol consumption is a major cause of fatty liver, and dietary saturated fats have been shown to protect against alcoholic fatty liver. This study investigated the mechanisms of how dietary saturated fat may modulate alcohol-induced hepatic lipid dyshomeostasis. METHODS: Male Sprague Dawley rats were pair-fed with 3 isocaloric liquid diets, control, alcohol, and medium chain triglyceride (MCT)/alcohol, respectively, for 8 weeks. The control and alcohol diets were based on the Lieber-DeCarli liquid diet formula with 30% total calories derived from corn oil (rich in unsaturated long chain fatty acids). The corn oil was replaced by MCT, which consists of exclusive saturated fatty acids, in the MCT/alcohol diet. HepG2 cell culture was conducted to test the effects of unsaturated fatty acids on hepatocyte nuclear factor-4α (HNF4α) and the role of HNF4α in regulating hepatocyte lipid homeostasis. RESULTS: Alcohol feeding caused significant lipid accumulation, which was attenuated by dietary MCT. The major effect of alcohol on hepatic gene expression is the up-regulation of CYP4A1, CD36, and GPAT3, and down-regulation of apolipoprotein B (ApoB). Dietary MCT further up-regulated CYP4A1 gene, normalized ApoB gene, and up-regulated MTTP and SCD1 genes. The protein level of HNF4α, a master transcription factor of the liver, was reduced by alcohol feeding, which was normalized by dietary MCT. Fatty acid profiling demonstrated that alcohol feeding dramatically increased hepatic unsaturated long chain fatty acyl species, particularly linoleic acid and oleic acid, which was attenuated by dietary MCT. Dietary MCT attenuated alcohol-reduced serum triglyceride level and modulated the fatty acid composition of the serum triglycerides. Cell culture study demonstrated polyunsaturated linoleic acid rather than monounsaturated oleic acid inactivated HNF4α in HepG2 cells. Knockdown of HNF4α caused lipid accumulation in HepG2 cells due to dysregulation of very low density lipoprotein secretion. CONCLUSIONS: Results suggest that dietary MCT prevents alcohol-induced hepatic lipid accumulation, at least partially, through reducing hepatic polyunsaturated long chain fatty acids and preserving HNF4α.

Adjuvant effects of Sijunzi decoction in chickens orally vaccinated with attenuated Newcastle-disease vaccine.

Many Chinese Herbal medicines (CHMs) and their components have been reported to enhance immunity. In this study, the capacity for the Chinese herbal medicine, oral administration Sijunzi Decoction (SJZD) in stimulating Newcastle disease virus(NDV) immunity in chickens was examined. Serum was sampled on days 20, 30, 40, 50 and 60 and tissues were collected on days 20, 40 and 60, respectively. The immune responses were determined by means of hemagglutination inhibition test, immunohistochemistry examination and semi-quantitative RT-PCR. The results showed that SJZD could increase the antibody titers and the area coefficient of IgA secreting cells, promote the expression of IL-2 mRNA in the whole immune period and IFN-γ mRNA was increased in the initial stage. The SJZD used was safe with no adverse effects on chicken weight or survival, providing evidence for the use of SJZD as an oral adjuvant.

Quercetin and Bornyl Acetate Regulate T-Lymphocyte Subsets and INF-γ/IL-4 Ratio In Utero in Pregnant Mice.

The objective of this study is to investigate the antiabortive effects of Quercetin and Bornvl Acetate and their immunological modulation at maternal-fetal interface. Lipopolysaccharide (LPS) was injected via tail vein to induce abortion in mice which received Quercetin and Bornvl Acetate at days 4-7 of gestation. Uterine CD4+/CD8+ T lymphocytes and IFN-γ/IL-4 of each group (n = 10) were detected by immunohistochemistry and enzyme-linked immunosorbent assay, respectively. The ratio of CD4+/CD8+ increased significantly (P < .01) in the uterus of LPS-induced abortion mice. In the Quercetin and Bornvl Acetate pretreated mice followed by LPS administration, the ratio of CD4+/CD8+ dropped to 0.562 ± 0.021, lower than that of LPS-abortion group (P < .01). The mean value of IFN-γ/IL-4 in LPS-treated mice was 0.310 ± 0.066, higher than that of Quercetin and Bornyl Acetate group. The results indicate that Quercetin and Bornyl Acetate have an antiabortive effect through modulation of immunological balance at maternal-fetal interface.

Synthesis and cellular biocompatibility of two nanophase hydroxyapatite with different Ca/P ratio.

The cellular biocompatibility of two types of nanophase hydroxyapatites including nanophase standard hydroxyapatite (n-HA) and nanophase calcium deficient hydroxyapatite (n-CDHA) synthesized by a wet chemical method were assessed using primary cultured osteoblasts. Cytotoxicity of both materials was investigated with L929 cell line. The MTT method was used to evaluate the proliferation of osteoblasts on the third day and ALP activity assay was carried out on the fifth day. SEM was used to observe the morphology of the osteoblasts on the third day. Two types of nanophase hydroxyapatite both showed no cytotoxicity. Higher cell proliferation was observed on n-CDHA than n-HA. At the same time, cells spread more actively on the n-CDHA group. The ALP level of n-CDHA was also significantly higher on the former. Our results show that the n-CDHA is more suitable for osteoblasts growth and is also helpful for ALP synthesis.

Effects of toosendanin on pregnancy and uterine immunity alterations in mice.

This study was conducted to explore the abortifacient effect and the mechanisms of the Chinese herbal medicine component toosendanin, and to elucidate the significance of the Th1 cytokines IFN-gamma and TNF-alpha, CD4+ and CD8+ T lymphocytes in the occurrence of abortion. Graded doses of toosendanin were given by intraperitoneal injection (i.p.) to mice at day 5, 6, 7 of gestation. The levels of Th1 cytokines (IFN-gamma, TNF-alpha) in serum and uterine tissues from mice sacrificed at day 8 were analyzed by enzyme linked immunosorbent assay (ELISA). Presence of T lymphocytes in endometrium was detected by immunohistochemistry. The results revealed that injection of toosendanin could produce a dose-dependent toxicity. The IFN-gamma, TNF-alpha content in serum and uterine tissues were increased significantly. The CD4+ and CD8+ T lymphocytes were also increased in the endometrium of toosendanin treated groups. In conclusion, toosendanin is pregnancy-toxic to animals and it is relevant to the increased contents of IFN-gamma, TNF-alpha and CD4+, CD8+ T lymphocytes.