Urinary phthalate metabolites in pregnant women: occurrences, related factors, and association with maternal hormones.

In this study, we aimed to evaluate phthalate metabolite levels in pregnant women, to explore the factors influencing exposure, and to assess phthalate metabolite levels in relation to thyroid hormone synthesis. We recruited 463 pregnant women and collected urine, blood, and questionnaire data at participant's first prenatal examination. Ten phthalate metabolites were analyzed: mono-isobutyl phthalate (MiBP); mono-methyl phthalate (MMP); mono-ethyl phthalate (MEP); mono-n-butyl phthalate (MnBP); mono-n-octyl phthalate (MOP); mono-benzyl phthalate (MBzP); and the metabolite of di-2-ethylhexyl phthalate (DEHP), which were mono (2-ethylhexyl) phthalate, mono-(2-ethyl-5-oxohexyl) phthalate, and mono-(2-ethyl-5-carboxypentyl) phthalate. Multivariable generalized estimating equation models and linear mixed models were used to predict urinary biomarker concentrations and to assess the associations between phthalate exposure and thyroid hormones. Positive associations were found between phthalate metabolites and lower education (MEP and MOP), living near the road (MEP, MnBP, and ∑DEHP), and consuming more puffed food (MEP and MBzP). In addition, MnBP (percent change [%△] = 4.25; 95% confidence interval [CI] = 0.32, 8.18) and ∑DEHP (%△ = 5.12; 95% CI = 1.25, 8.99) were positively associated with thyroid-stimulating hormones, although MEP and MnBP were inversely associated with free thyroxine and total triiodothyronine. Our findings suggest that certain habits and behaviors were predictive of the positive presence of phthalate metabolites and that certain phthalate esters are associated with altered thyroid hormone levels.

The antioxidant activities of flavonoids in Jerusalem artichoke (Helianthus tuberosus L.) leaves and their quantitative analysis.

The main targets of this work were to evaluate the antioxidative properties of flavonoids in Jerusalem artichoke (Helianthus tuberosus L.) leaves and quantitatively determine their contents. 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) and hydroxyl free radicals scavenging assays were performed to determine their antioxidative capacities. The validated ultra high-performance liquid chromatography-quadrupole-time-of-flight/mass spectrometry (UHPLC-Q-TOF/MS) method was subsequently applied to the quality evaluation of eleven batches of Jerusalem artichoke leaves grown in different habitats at different harvesting time. Results indicated that two flavonoids isolated from Jerusalem artichoke leaves showed stronger antioxidant effects than the positive control, butylated hydroxytoluene (BHT). And the total contents of the two flavonoids in the Jerusalem artichoke leaves of flowering stage from Dalian, Liaoning Province, China, were the highest, their contents varied significantly depending on region and harvesting time. This study indicated that the leaves of Jerusalem artichoke possessed excellent antioxidant properties, highlighting their candidacy as natural antioxidants, which could be utilized therapeutically to protect the body from diseases caused by oxidative stress.

Sequential Extraction, Characterization, and Analysis of Pumpkin Polysaccharides for Their Hypoglycemic Activities and Effects on Gut Microbiota in Mice.

This study aimed to extract polysaccharides from pumpkin, characterize the structures of four of them, and evaluate their in vitro antioxidant and hypoglycemic activities. Additionally, an animal model of type 2 diabetes mellitus (T2DM) was established and used to determine their hypoglycemic and hypolipidemic effects in vivo, and the underlying mechanisms related to the regulation of gut microbiota. Water-extracted crude pumpkin polysaccharides (W-CPPs), water extraction and alcohol precipitation crude pumpkin polysaccharides (WA-CPPs), deproteinized pumpkin polysaccharides (DPPs), and refined pumpkin polysaccharides (RPPs) were sequentially extracted and purified from pumpkin powder by hot water extraction, water extraction, and alcohol precipitation, deproteinization and DEAE-52 cellulose gel column, respectively. The extraction and purification methods had significant influence on the extraction yield, physicochemical properties, and in vitro antioxidant and hypoglycemic activities. W-CCP and RPPs had a significant positive free radical-scavenging capacities and inhibitory activities on α-glucosidase and α-amylase. RPP-3 not only inhibited the uptake of glucose in Caco-2 monolayer but also promoted the excretion of glucose, while RPP-2 had no inhibitory effect. Animal experiment results showed that W-CPP treatment significantly improved the T2DM symptoms in mice, which included lowering of fasting blood glucose (FBG), reducing insulin resistance (IR), and lowering of blood lipid levels. It increased the diversity of intestinal flora and reduced the harmful flora of model mice, which included Clostridium, Thermoanaerobe, Symbiotic bacteria, Deinococcus, Vibrio haematococcus, Proteus gamma, and Corio. At the family level, W-CPP (1,200 mg/kg) treatment significantly reduced the abundance of Erysipelotrichaceae, and the Akkermanaceae of Verrucobacterium became a biomarker. Pumpkin polysaccharides reshaped the intestinal flora by reducing Erysipelotrichaceae and increasing Akkermansia abundance, thereby improving blood glucose and lipid metabolism in the T2DM mice. Our results suggest that W-CCP and RPP-3 possess strong antioxidant and hypoglycemic activities, and are potential candidates for food additives or natural medicines.

Purification and identification of corn peptides that facilitate alcohol metabolism by semi-preparative high-performance liquid chromatography and nano liquid chromatography with electrospray ionization tandem mass spectrometry.

In this study, peptides that facilitate alcohol metabolism were purified and identified from corn protein hydrolysates. The ultra-filtered fraction with a molecular weight < 3 kDa (F3) potential activity was separated into six fractions (F3-H1-F3-H6) by semi-preparative high-performance liquid chromatography. Among the resultant six fractions, F3-H4 and F3-H5 exhibited the highest ability to eliminate alcohol in vivo. A total of 16 peptides with strong signal values were identified from F3-H4 and F3-H5 fractions by nano liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Several identified peptides were then selected and synthesized to determine their potential to facilitate alcohol metabolism. We found that Leu-Leu and Pro-Phe were the key structure units in Gln-Leu-Leu-Pro-Phe responsible for this peptide's ability to facilitate alcohol metabolism. However, the role of Leu-Leu and Pro-Phe may be affected by peptide chain length and hydrophobic properties. Our results have thus provided some insight into the study of the structure-activity relationships of corn peptides.

Bivalent Copper Ions Promote Fibrillar Aggregation of KCTD1 and Induce Cytotoxicity.

Potassium channel tetramerization domain containing 1 (KCTD1) family members have a BTB/POZ domain, which can facilitate protein-protein interactions involved in the regulation of different signaling pathways. KCTD proteins have potential Zn(2+)/Cu(2+) binding sites with currently unknown structural and functional roles. We investigated potential Cu(2+)-specific effects on KCTD1 using circular dichroism, turbidity measurement, fluorescent dye binding, proteinase K (PK) digestion, cell proliferation and apoptosis assays. These experiments indicate that the KCTD1 secondary structure assumes greater ß-sheet content and the proteins aggregate into a PK-resistant form under 20 µM Cu(2+), and this ß-sheet-rich aggregation with Cu(2+) promotes fibril formation, which results in increased cell toxicity by apoptosis. Our results reveal a novel role for Cu(2+) in determining the structure and function of KCTD1.

High performance liquid chromatography (HPLC) fingerprints and primary structure identification of corn peptides by HPLC-diode array detection and HPLC-electrospray ionization tandem mass spectrometry.

Corn peptides (CPs) are reported to have many biological functions, such as facilitating alcohol metabolism, antioxidation, antitumor, antihypertension, and hepatoprotection. To develop a method for quality control, the high-performance liquid chromatography (HPLC) system was applied. Twenty-eight common peaks were found in all the CPs of corn samples from Enshi, China, based on which, a fingerprinting chromatogram was established for use in quality control in future research. Subsequently, the major chemical constituents of these common peaks were identified respectively using the HPLC-diode-array detection electrospray ionization tandem mass spectrometry (DAD-ESI-MS/MS) system, and 48 peptide fractions were determined ultimately. This was the first time for the majority of these peptides to be reported, and many of them contained amino acids of glutamine (Q), L and A, which might play an important role in the exhibition of the bioactivities of CPs. Many peptides had a similar primary structure to the peptides which had been proven to be bioactive such as facilitating alcohol metabolism, scavenging free radicals, and inhibiting lipid peroxidation. This systematical analysis of the primary structure of CPs facilitated subsequent studies on the relationship between the structures and functions, and could accelerate holistic research on CPs.

Corn peptides protect against thioacetamide-induced hepatic fibrosis in rats.

Certain bioactive peptides are reported to be able to alleviate hepatic fibrosis. Our previous work has confirmed the hepatoprotective effect of corn peptides (CPs) that are prepared from a high protein by-product, corn gluten meal, on acute liver injury in an animal model. However, the antifibrotic activity of CPs remained to be elucidated. In this study, the hepatoprotective effect of CPs on thioacetamide (TAA)-induced liver fibrosis was tested. Results showed that CPs (100 mg/kg body weight) significantly decreased the levels of alanine transaminase/aspartate transaminase, laminin, type IV collagen, and type III collagen in serum and increased the serum albumin levels and total antioxidant capacity. Additionally, with CP treatment (100 mg/kg body weight), a significant decrease was observed in the levels of malondialdehyde, nitric oxide, hydroxyproline, transforming growth factor ß1, and lactate dehydrogenase activity as well as the liver index, while the activity of superoxidedismutase was significantly increased in livers. The histological and morphological analysis showed that the hepatocyte structure in CP-treated rats was superior to that of TAA-injured rats, and inflammation and fibrosis were also ameliorated. Therefore, CPs can be used as an option for prevention and adjuvant therapy of liver fibrosis.

Apoptosis in human hepatoma HepG2 cells induced by corn peptides and its anti-tumor efficacy in H22 tumor bearing mice.

This study was aimed at evaluating the anti-tumor mechanism of corn peptides (CPs). In vitro, the results showed that CPs significantly inhibited cell viability in both a dose- and a time-dependent manner. CPs treatment induced S cell-cycle arrest and caused apoptotic death in HepG2 cells. It was observed that CPs caused the increased in Bax/Bcl-2 ratio and triggered the activation of Cleaved-caspase-3, p53 in HepG2 cells. In vivo, the results showed that CPs could not only inhibit the growth of the tumor, but also enhance the spleen index, as well as the level of IL-2, IFN-γ and TNF-α. Moreover, CPs could prolong the survival time in H22-bearing mice. This study demonstrated that CPs was an apoptosis inducer in HepG2 cells, that it could effectively inhibit hepatocellular carcinoma in vivo via enhancement of host immune system function, and that it could be a safe and effective anticancer, bioactive agent or functional food.

The primary structure identification of a corn peptide facilitating alcohol metabolism by HPLC-MS/MS.

The aim of this study is to identify the primary structure of corn peptides (CPs) with a facilitating alcohol metabolism effect. Corn protein was hydrolyzed by Alcalase first. The hydrolysate, crude corn peptides (CPs), was then fractionated through ultrafiltration technology. The primary structure of a peptide from the fraction (Mm<5kDa) was identified by HPLC-MS/MS, coupled with the peptide sequence retrieval using the MS-MS online database. The amino acid sequence of the peptide was determined as Q-L-L-P-F, and the pentapeptide was synthesized by Fmoc solid-phase peptide synthesis (SPPS) method. Its ability to facilitate alcohol metabolism was evaluated in vivo. Results showed that the synthetic peptide (10mg/kg) had a higher ability to eliminate alcohol in vivo compared to the mixed peptides (Mm<5kDa, 200mg/kg). In conclusion, the pentapeptide Q-L-L-P-F has a potent ability in facilitating alcohol metabolism, and this pentapeptide is the main bioactive component in the mixed peptides obtained from corn.