Multi-element Exposure and Cognitive Function in Rural Elderly Chinese.

To investigate the relationship between selenium (Se) based multi-element combined exposure and cognitive function in rural elderly individuals, a cross-sectional study was conducted. The study involved 416 older adults aged 60 and above, residing in four different areas of Enshi county, China, with varying soil Se levels. Inductively coupled plasma mass spectrometry (ICP-MS) was employed to measure the concentrations of Se, copper (Cu), iron (Fe), zinc (Zn), calcium (Ca), magnesium (Mg), cadmium (Cd), arsenic (As), and lead (Pb) in whole blood. Nine standard cognitive tests were applied to assess cognitive function. Analysis of the least absolute shrinkage and selection operator regression (LASSO), covariance (ANCOVA), and generalized linear model (GLM) were utilized to investigate the relationship between element exposure and cognitive function. The results of LASSO revealed that Se, Cu, Fe, Zn, Ca, and Pb were independently identified to be associated with cognition. Both ANCOVA and GLM demonstrated that Se and Ca were correlated with cognitive function. The multi-element model showed higher composite Z scores of 0.32 (95% CI: 0.09 to 0.55) for log-transformed Se (P = 0.007), 0.75 (95% CI: 0.01 to 1.49) for log-transformed Cu (P = 0.048), and a lower score of - 0.67 (95% CI: - 1.26 to - 0.08) for log-transformed Ca (P = 0.025). Furthermore, there was evidence that Se could counteract the negative impact of Ca on cognitive function (P for interaction = 0.031). Our findings suggested that higher levels of Se and Cu were associated with better cognitive function in the elderly and Se can counteract the cognitive damage caused by Ca.

Blood Selenium and Serum Glutathione Peroxidase Levels Were Associated with Serum ß-Amyloid in Older Adults.

BACKGROUND: Studies have established the association between blood ß-amyloid (Aß) levels and Alzheimer's disease, but population-based studies concerning the association between selenium (Se) and Aß levels in blood samples are very limited. Therefore, we explored the association in an elderly population with Se status and serum Aß measures. METHODS: A cross-sectional study on 469 elderly individuals from four rural counties with diverse soil Se levels was carried out. Fasting blood Se, serum selenoprotein P (SELENOP), and glutathione peroxidase (GPX), serum Aß42, and Aß40 were measured. Quantile regression models were used to determine the associations of blood Se, serum GPX, and SELENOP with Aß levels. RESULTS: Significant negative associations were observed between blood Se and serum Aß42 and Aß40 levels at all percentiles (P < 0.05). The associations were generally stronger at higher Aß42 and Aß40 percentiles than lower Aß42 and Aß40 percentiles. Blood Se was positively associated with serum Aß42/Aß40 ratio at 25th, 50th, and 75th percentiles. Significant positive associations were observed between serum GPX and Aß42 and Aß40 levels at all percentiles (P < 0.05). The positive associations were generally stronger at higher Aß42 and Aß40 percentiles than at lower percentiles. Serum GPX was negatively associated with Aß42/Aß40 ratio at 25th, 50th, 75th, and 95th percentiles. No associations with serum SELENOP and Aß levels were observed. CONCLUSIONS: Our results suggest that higher Se levels are associated with lower serum Aß42 and Aß40 levels and with higher Aß42/Aß40 ratio, and the results are specific for different selenoproteins.

Determination of Trace Rhodamine B in Chili Oil by Deep Eutectic Solvent Extraction and an Ultra High-Performance Liquid Chromatograph Equipped with a Fluorescence Detector.

Rhodamine B was forbidden in food by law because of its carcinogenic properties to humans. However, due to its low cost, it was often used to dope chili oil by some counterfeiters to improve its natural color. However, it was difficult to quantify rhodamine B in chili oil due to its complex substrates and high viscosity. In this study, deep eutectic solvents, comprised of choline chloride and ethylene glycol, were first used as an extraction medium to separate rhodamine B from chili oil.

Conserved metabolic steps for sporopollenin precursor formation in tobacco and rice.

The development of pollen wall with proper sporopollenin deposition is essential for pollen viability and male fertility in flowering plants. Sporopollenin is a complex biopolymer synthesized from fatty acid and phenolic derivatives. Recent investigations in Arabidopsis have identified a number of anther-specific genes involved in the production of fatty-acyl monomers potentially required for exine formation. The existence of ancient biochemical pathways for sporopollenin biosynthesis has been widely proposed but experimental evidence from plant species other than Arabidopsis is not extensively available. Here, we investigated the metabolic steps catalyzed by the anther-specific acyl-CoA synthetase (ACOS), polyketide synthase (PKS) and tetraketide α-pyrone reductase (TKPR). Using fatty acids as starting substrates, sequential activities of heterologously expressed tobacco enzymes NtACOS1, NtPKS1 and NtTKPR1 resulted in the production of reduced tetraketide α-pyrones. Transgenic RNA interference lines were then generated for the different tobacco genes which were demonstrated to be indispensable for normal pollen development and male fertility. Similarly, recombinant rice OsPKS1 and OsTKPR1 were shown to function as downstream enzymes of NtACOS1. In addition, insertion mutant lines for these rice genes displayed different levels of impaired pollen and seed formation. Taken together, reduced tetraketide α-pyrones appear to represent common sporopollenin fatty-acyl precursors essential for male fertility in taxonomically distinct plant species.

Direct trapping of acrylamide as a key mechanism for niacin's inhibitory activity in carcinogenic acrylamide formation.

The inhibitory mechanism of niacin, which was found in our previous study to effectively reduce acrylamide (AA) formation in both chemical models and fried potato strips, was investigated in the present study. Maillard chemical models containing the amino acid asparagine and glucose with or without niacin were closely examined by liquid chromatography/tandem mass spectrometry. Comparison of the chemical profiles revealed two additional peaks in models where niacin was present together with the AA precursors, which thus suggests the formation of compounds from reactions between niacin and other chemical species in the model systems. The predicted molecular weights of these two analytes were consistent with adducts formed between niacin and asparagine or AA, respectively. The niacin-acrylamide adduct was also detected in fried potato strips pretreated with niacin. In addition, the niacin-acrylamide adduct was subsequently purified and characterized by NMR spectroscopy as 1-propanamide-3-carboxy pyridinium, a novel compound that has never been reported previously. Furthermore, incubation of niacin with AA in simulated physiological conditions showed that niacin was capable of significantly reducing the level of AA. Findings from this study suggest that niacin not only has the potential to remove AA from food products during heat treatment by directly trapping it but also is a potential agent to scavenge AA in human body.