Melatonin mitigates manganese-induced neural damage via modulation of gut microbiota-metabolism in mice.

Manganese (Mn), a common environmental and occupational risk factor for Parkinson's disease (PD), can cause central nervous system damage and gastrointestinal dysfunction. The melatonin has been shown to effectively improve neural damage and intestinal microbiota disturbances in animal models. This research investigated the mechanism by which exogenous melatonin prevented Mn-induced neurogenesis impairment and neural damage. Here, we established subchronic Mn-exposed mice model and melatonin supplement tests to evaluate the role of melatonin in alleviating Mn-induced neurogenesis impairment. Mn induced neurogenesis impairment and microglia overactivation, behavioral dysfunction, gut microbiota dysbiosis and serum metabolic disorder in mice. All these events were reversed with the melatonin supplement. The behavioral tests revealed that melatonin group showed approximately 30 % restoration of motor activity. According to quantitative real time polymerase chain reaction (qPCR) results, melatonin group showed remarkable restoration of the expression of dopamine neurons and neurogenesis markers, approximately 46.4 % (TH), 68.4 % (DCX in hippocampus) and 48 % (DCX in striatum), respectively. Interestingly, melatonin increased neurogenesis probably via the gut microbiota and metabolism modulation. The correlation analysis of differentially expressed genes associated with hippocampal neurogenesis indicated that Firmicutes-lipid metabolism might mediate the critical repair role of melatonin in neurogenesis in Mn-exposed mice. In conclusion, exogenous melatonin supplementation can promote neurogenesis, and restore neuron loss and neural function in Mn-exposed mice, and the multi-omics results provide new research ideas for future mechanistic studies.

Status and influencing factors of undergraduate midwifery students' core competencies: A cross sectional study.

INTRODUCTION: Midwifery undergraduate students' core competencies directly affect the quality of midwifery services and overall quality of midwifery teams. However, limited research has explored the core competencies of undergraduate midwifery students in China. OBJECTIVES: This study aimed to describe the level of core competencies among undergraduate midwifery students in China and investigated possible associated factors. DESIGN: This was a cross-sectional descriptive study. SETTINGS AND PARTICIPANTS: The study population comprised third- and fourth-year undergraduate midwifery students at Zunyi Medical University in Guizhou Province in southwest China (n = 207, response rate 94.1 %). METHODS: Data were collected using an online survey that included a general information questionnaire, a general self-efficacy scale, and a core competencies self-assessment questionnaire for midwifery undergraduates. Data were statistically analyzed using SPSS 18.0. Pearson's correlation analysis was used to explore the relationship between self-efficacy and the core competencies. Stepwise multiple linear regression was used to explore influencing factors. RESULTS: The total score for the core competencies among midwifery undergraduates was 118.46 (8.97). The highest mean score was for professional attitude, 4.21 (0.43), and the lowest was for professional skills, 3.70 (0.30). We found a positive association between self-efficacy and core competencies (r = 0.251, P < 0.01). Grade (ß = 0.261, P < 0.01), scholarship (ß = -0.231, P < 0.01), work intention (ß = -0.135, P < 0.05), and self-efficacy (ß = 0.207, P < 0.01) significantly influenced undergraduate midwifery students' core competencies (R2 = 0.189, adjusted R2 = 0.173, F = 11.775, P < 0.001). CONCLUSIONS: Undergraduate midwifery students showed moderate core competencies, indicating room for improvement. Fourth-grade midwifery students had higher core competencies than third-grade students. Additionally, scholarship, work intention, and self-efficacy were significant influencing factors. Midwifery educators should examine students' core competencies and explore targeted interventions, particularly for those with low self-efficacy and core competencies.

A spatial optimal allocation method considering multi-attribute decision making and multiple BMPs random combination in sub-watersheds.

Best management practices (BMPs) have been extensively employed in effective watershed management for non-point source pollution. The weights of objective functions and the restrictive conditions of combined BMPs are the vital requirements for BMPs allocation. Therefore, it is more beneficial to explore that a spatial optimal allocation method considering multi-attribute decision making and multiple BMPs random combination. Here is the novel framework based on Soil and Water Assessment Tool (SWAT) and the Non-dominated Sorting Genetic Algorithm II (NSGA-Ⅱ), which considers multiple objectives in deriving watershed-scale pollution control practices by considering BMPs cost and combined reduction rates of total nitrogen (TN) and total phosphorus (TP). The framework also integrates combined Entropy Weight method (EWM) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to solve the weights of TN and TP, and considers the attributes of the sub-basin itself, which is more local suitability. Four categories of BMPs, tillage management, nutrient management, vegetative filter strips, and landscape management, were evaluated in the Jing River Basin (JRB) and resulted in reduction rates of 9.77%, 10.53%, 16.40%, and 14.27% averagely, respectively. BMP allocation schemes, derived from multi-objective optimization, are stratified into three financial scenarios. Low-cost scenario, costing up to 2 billion RMB, primarily targets the grain for green program in 28.81% of sub-basins. Medium-cost scenario, between 2 and 6 billion RMB, predominantly utilizes the grain for green in areas with a slope greater than 15°, accounting for 20.00% of sub-basins. High-cost scenario exceeds 6 billion RMB, mainly due to the implementation of multiple combination measures. The three configuration scenarios can provide decision-makers with a trade-off between measure costs and reduction efficiency. Overall, the innovative framework not only facilitates cost-effective implementation but provides a beneficial methodology for selecting cost-effective conservation practices in other regions.

SIRT3-Mediated Deacetylation of SDHA Rescues Mitochondrial Bioenergetics Contributing to Neuroprotection in Rotenone-Induced PD Models.

Mitochondrial dysfunction is critically involved in the degeneration of dopamine (DA) neurons in the substantia nigra, a common pathological feature of Parkinson's disease (PD). Previous studies have demonstrated that the NAD+-dependent acetylase Sirtuin 3 (SIRT3) participates in maintaining mitochondrial function and is downregulated in aging-related neurodegenerative disorders. The exact mechanism of action of SIRT3 on mitochondrial bioenergetics in PD pathogenesis, however, has not been fully described. In this study, we investigated the regulatory role of SIRT3-mediated deacetylation of mitochondrial complex II (succinate dehydrogenase) subunit A (SDHA) and its effect on neuronal cell survival in rotenone (ROT)-induced rat and differentiated MN9D cell models. The results revealed that SIRT3 activity was suppressed in both in vivo and in vitro PD models. Accompanying this downregulation of SIRT3 was the hyperacetylation of SDHA, impaired activity of mitochondrial complex II, and decreased ATP production. It was found that the inhibition of SIRT3 activity was attributed to a reduction in the NAD+/NADH ratio caused by ROT-induced inhibition of mitochondrial complex I. Activation of SIRT3 by icariin and honokiol inhibited SDHA hyperacetylation and increased complex II activity, leading to increased ATP production and protection against ROT-induced neuronal damage. Furthermore, overexpression of SDHA also exerted potent protective benefits in cells treated with ROT. In addition, treatment of MN9D cells with the NAD+ precursor nicotinamide mononucleotide increased SIRT3 activity and complex II activity and promoted the survival of cells exposed to ROT. These findings unravel a regulatory SIRT3-SDHA axis, which may be closely related to PD pathology. Bioenergetic rescue through SIRT3 activation-dependent improvement of mitochondrial complex II activity may provide an effective strategy for protection from neurodegeneration.

Salvianolic acid B ameliorates myocardial fibrosis in diabetic cardiomyopathy by deubiquitinating Smad7.

BACKGROUND: Salvianolic acid B (Sal B), a water-soluble phenolic compound derived from Salvia miltiorrhiza Bunge, is commonly used in Traditional Chinese Medicine to treat cardiovascular disease. In our previous study, Sal B protected against myocardial fibrosis induced by diabetic cardiomyopathy (DCM). This study aimed to investigate the ameliorative effects and potential mechanisms of Sal B in mitigating myocardial fibrosis induced by DCM. METHODS: Various methods were used to investigate the effects of Sal B on myocardial fibrosis induced by DCM in vivo and in vitro. These methods included blood glucose measurement, echocardiography, HE staining, Masson's trichrome staining, Sirius red staining, cell proliferation assessment, determination of hydroxyproline levels, immunohistochemical staining, evaluation of fibrosis-related protein expression (Collagen-I, Collagen-III, TGF-ß1, p-Smad3, Smad3, Smad7, and α-smooth muscle actin), analysis of Smad7 gene expression, and analysis of Smad7 ubiquitin modification. RESULTS: The animal test results indicated that Sal B significantly improved cardiac function, inhibited collagen deposition and phenotypic transformation, and ameliorated myocardial fibrosis in DCM by upregulating Smad7, thereby inhibiting the TGF-ß1 signaling pathway. In addition, cell experiments demonstrated that Sal B significantly inhibited the proliferation, migration, phenotypic transformation, and collagen secretion of cardiac fibroblasts (CFs) induced by high glucose (HG). Sal B significantly decreased the ubiquitination of Smad7 and stabilized the protein expression of Smad7, thereby increasing the protein expression of Smad7 in CFs and inhibiting the TGF-ß1 signaling pathway, which may be the potential mechanism by which Sal B mitigates myocardial fibrosis induced by DCM. CONCLUSION: This study revealed that Sal B can improve myocardial fibrosis in DCM by deubiquitinating Smad7, stabilizing the protein expression of Smad7, and blocking the TGF-ß1 signaling pathway.

Intermittent hypoxia therapy ameliorates beta-amyloid pathology via TFEB-mediated autophagy in murine Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder. Impaired autophagy in plaque-associated microglia (PAM) has been reported to accelerate amyloid plaque deposition and cognitive impairment in AD pathogenesis. Recent evidence suggests that the transcription factor EB (TFEB)-mediated activation of the autophagy-lysosomal pathway is a promising treatment approach for AD. Moreover, the complementary therapy of intermittent hypoxia therapy (IHT) has been shown to upregulate autophagy and impart beneficial effects in patients with AD. However, the effect of IHT on PAM remains unknown. METHODS: 8-Month-old APP/PS1 mice were treated with IHT for 28 days. Spatial learning memory capacity and anxiety in mice were investigated. AD pathology was determined by the quantity of nerve fibers and synapses density, numbers of microglia and neurons, Aß plaque deposition, pro-inflammatory factors, and the content of Aß in the brain. TFEB-mediated autophagy was determined by western blot and qRT-PCR. Primary microglia were treated with oligomeric Aß 1-42 (oAß) combined with IHT for mechanism exploration. Differential genes were screened by RNA-seq. Autophagic degradation process of intracellular oAß was traced by immunofluorescence. RESULTS: In this study, we found that IHT ameliorated cognitive function by attenuating neuronal loss and axonal injury in an AD animal model (APP/PS1 mice) with beta-amyloid (Aß) pathology. In addition, IHT-mediated neuronal protection was associated with reduced Aß accumulation and plaque formation. Using an in vitro PAM model, we further confirmed that IHT upregulated autophagy-related proteins, thereby promoting the Aß autophagic degradation by PAM. Mechanistically, IHT facilitated the nuclear localization of TFEB in PAM, with TFEB activity showing a positive correlation with Aß degradation by PAM in vivo and in vitro. In addition, IHT-induced TFEB activation was associated with the inhibition of the AKT-MAPK-mTOR pathway. CONCLUSIONS: These results suggest that IHT alleviates neuronal damage and neuroinflammation via the upregulation of TFEB-dependent Aß clearance by PAM, leading to improved learning and memory in AD mice. Therefore, IHT may be a promising non-pharmacologic therapy in complementary medicine against AD.

On-line identification of the chemical constituents of Polygoni Multiflori Radix by UHPLC-Q-ToF MS/MS.

Introduction: Polygoni Multiflori Radix (PMR) is a type of Chinese herbal medicine with rich chemical composition and pharmacological activity used widely in medicine and food. However, in recent years, there have been increasing numbers of negative reports about its hepatotoxicity. Identification of its chemical constituents for quality control and safe use is very important. Methods: Three solvents of different polarities (water, 70% ethanol, and 95% ethanol solution) were used to extract the compounds from PMR. Extracts were analyzed and characterized by ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-ToF MS/MS) in the negative-ion mode. Results: 152 compounds were detected and identified: 50 anthraquinones, 33 stilbene derivatives, 21 flavonoids, seven naphthalene compounds, and 41 other compounds. Eight other compounds were reported for the first time in the PMR-related literature, and eight other compounds were potentially new compounds. Discussion: This study lays a solid foundation for the screening of toxicity and quality-control indicators of PMR.

Correlation between dietary theobromine intake and low cognitive performance in older adults in the United States: A cross-sectional study based on the National Health and Nutrition Examination Survey.

BACKGROUND AND OBJECTIVES: Few studies have investigated the effects of dietary theobromine intake on the cognitive performance of older adults. Therefore, we investigated these effects in older adults in the United States. METHODS AND STUDY DESIGN: In this cross-sectional study, we used data (2011-2014) from the National Health and Nutrition Examination Survey. Intake of theobromine intake was obtained through two 24-h dietary recall interviews and was adjusted by energy. Cognitive performance was assessed using the animal fluency test, Consortium to Establish a Registry for Alzheimer's Disease Word Learning subtest (CERAD), and Digit Symbol Substitution Test (DSST). Logistic regression and restricted cubic spline models were constructed to evaluate the correlation between the dietary intake of theobromine from different sources and the likelihood of low cognitive performance. RESULTS: The fully adjusted model revealed that compared with the lowest quintile, the odds ratios (with 95% confidence intervals) of cognitive performance in the CERAD test were 0.42 (0.28-0.64), 0.34 (0.14-0.83), 0.25 (0.07-0.87), and 0.35 (0.13-0.95) for the highest quintile of total theobromine intake and that from chocolate, coffee, and cream, respectively. Dose-response relationship analysis indicated nonlinear correlations between the likelihood of low cognitive performance and die-tary theobromine (total intake and that from chocolate, coffee, and cream). An L-shaped relationship was ob-served between total theobromine intake and cognitive performance in the CERAD test. CONCLUSIONS: The dietary intakes of theobromine (total and that from chocolate, coffee, and cream) may protect older adults, particularly men, against low cognitive performance.

Exploratory Quality Control Study for Polygonum multiflorum Thunb. Using Dinuclear Anthraquinones with Potential Hepatotoxicity.

In recent years, the hepatotoxicity of Polygoni Multiflora Radix (PMR) has attracted increased research interest. Some studies suggest that anthraquinone may be the main hepatotoxic component. Most of the relevant studies have focused on the mononuclear anthraquinone component rather than binuclear anthraquinones. The hepatotoxicity of dinuclear anthraquinone (dianthrone) was investigated in a cell-based model. Next, a method for the determination of six free and total dianthonones in PMR and PMR Praeparata (PMRP) was established using ultra-high-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-QQQ-MS/MS), which was then used to analyze the collected samples. The data show that four binuclear anthraquinone compounds were hepatotoxic and may be potential toxicity indicators for the safety evaluation of PMR and PMRP. Herein, we provide a theoretical basis for the improvement of PMRP quality standards.

[Contamination level and population exposure assessment of chloropropanol esters in edible vegetable oil in Shandong Province from 2016 to 2020].

OBJECTIVE: To investigate the contamination of 2-chloropropanol esters and 3-chloropropanol esters in commercial edible vegetable oils in Shandong Province, and to assess the dietary 3-chloropropanol esters exposure and the health risk of intaking 3-chloropropanol esters. METHODS: From 2016 to 2020, 406 individually packaged edible vegetable oils were collected from stores and farmers' markets in 16 prefecture-level cities in Shandong Province. According to the 2016 National Food Contamination and Harmful Factors Risk Monitoring Manual, using gas chromatography-triple quadrupole tandem mass spectrometry detection, isotope internal standard method for quantification, laboratory determination of 2-chloropropanol ester and 3-chloropropanol in vegetable oil ester content. Combined with population weight, oil consumption and monitoring data, the point assessment method was used to evaluate the exposure of residents in Shandong Province to 3-chloropropanol esters. RESULTS: The detection rate of 3-chloropropanol ester was 92.4%(375/406), the concentration range was<limit of detection(LOD)-18.4 mg/kg, the median was 0.470 mg/kg, the average was 0.833 mg/kg, and the maximum value was 18.4 mg/kg in rice oil; the detection rate of 2-chloropropanol ester was 88.7%(360/406), the concentration range was <LOD-8.46 mg/kg, the median value was 0.204 mg/kg, the average value was 0.432 mg/kg, and the maximum value was 8.46 mg/kg in rice oil. The average exposure of each age group was less than the tolerable daily intake, and the high-end exposure of the children(2-6 years old) and adolescents(7-10 years old) group was greater than the tolerable daily intake. CONCLUSION: The contamination of chloropropanol esters of edible vegetable oil in Shandong Province from 2016 to 2020 is widespread, and the highest detection value appears in rice oil. Children(2-6 years old) and adolescents(7-10 years old) in high-risk situations ingest 3-chloropropanol esters present health risks.

Enhanced methane production in anaerobic digestion: A critical review on regulation based on electron transfer.

Anaerobic digestion (AD) is a potential bioprocess for waste biomass utilization and energy conservation. Various iron/carbon-based CMs (e.g., magnetite, biochar, granular activated carbon (GAC), graphite and zero valent iron (ZVI)) have been supplemented in anaerobic digestors to improve AD performance. Generally, the supplementation of CMs has shown to improve methane production, shorten lag phase and alleviate environmental stress because they could serve as electron conduits and promote direct interspecies electron transfer (DIET). However, the CMs dosage varied greatly in previous studies and CMs wash out remains a challenge for its application in full-scale plants. Future work is recommended to standardize the CMs dosage and recover/reuse the CMs. Moreover, additional evidence is required to verify the electrotrophs involved in DIET.

A stepwise strategy integrating metabolomics and pseudotargeted spectrum-effect relationship to elucidate the potential hepatotoxic components in Polygonum multiflorum.

Polygonum multiflorum (PM) Thunb., a typical Chinese herbal medicine with different therapeutic effect in raw and processed forms, has been used worldwide for thousands of years. However, hepatotoxicity caused by PM has raised considerable concern in recent decades. The exploration of toxic components in PM has been a great challenge for a long time. In this study, we developed a stepwise strategy integrating metabolomics and pseudotargeted spectrum-effect relationship to illuminate the potential hepatotoxic components in PM. First, 112 components were tentatively identified using ultraperformance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-Q-TOF-MS). Second, based on the theory of toxicity attenuation after processing, we combined the UPLC-Q-TOF-MS method and plant metabolomics to screen out the reduced differential components in PM between raw and processed PM. Third, the proposed pseudotargeted MS of 16 differential components was established and applied to 50 batches of PM for quantitative analysis. Fourth, the hepatocytotoxicity of 50 batches of PM was investigated on two hepatocytes, LO2 and HepG2. Last, three mathematical models, gray relational analysis, orthogonal partial least squares analysis, and back propagation artificial neural network, were established to further identify the key variables affecting hepatotoxicity in PM by combining quantitative spectral information with toxicity to hepatocytes of 50 batches of PM. The results suggested that 16 components may have different degrees of hepatotoxicity, which may lead to hepatotoxicity through synergistic effects. Three components (emodin dianthrones, emodin-8-O-ß-D-glucopyranoside, PM 14-17) were screened to have significant hepatotoxicity and could be used as toxicity markers in PM as well as for further studies on the mechanism of toxicity. Above all, the study established an effective strategy to explore the hepatotoxic material basis in PM but also provides reference information for in-depth investigations on the hepatotoxicity of PM.

Pharmacokinetics and metabolism of trans-emodin dianthrones in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Polygonum multiflorum Thunb. (PM) is a common traditional Chinese medicine with diverse biological activities of resolving toxins, nourishing livers and promoting hairs. Nevertheless, in recent years hepatotoxic adverse reactions caused by the administration of PM have raised worldwide concerns. In our previous study, we found that emodin dianthrones showed hepatotoxicity and may be potential toxicity markers. However, the metabolic transformation and pharmacokinetic behavior of emodin dianthrones in vivo have still not been elucidated. AIM OF THE STUDY: Taking trans-emodin dianthrones (TED) as an example, the present study was conducted to investigate the pharmacokinetics and bioavailability of TED in rats and characterized its metabolic transformation in the plasma, urine and feces of rats. MATERIALS AND METHODS: A rapid and sensitive UPLC-qqq-MS/MS method was developed for accurate quantification of TED in plasma and successfully applied to the pharmacokinetic evaluation of TED in rats after intravenous and oral administration. A reliable UFLC-Q-TOF-MS high resolution mass spectrometry combined with a scientific metabolite identification strategy was used to comprehensively characterize the metabolic transformation of TED in plasma, urine and feces in rats. RESULTS: The established UPLC-qqq-MS/MS method had a linear range of 1-500 ng/mL, and the method was accurate and reliable to meet the quantitative requirements. When 20 mg/kg TED was given by gavage rats, it was rapidly absorbed into the circulatory system and had a long half-life time of 6.44 h and wide tissue distribution in vivo. While intravenous injection of 0.4 mg/kg TED in rats, it was rapidly metabolized and eliminated with a half-life time of 1.82 h. The oral absorption bioavailability of TED was only 2.83%. Furthermore with a sensitive UFLC-Q-TOF-MS technique and metabolite identification strategy, 21 metabolites were successfully identified, including 11 in plasma, 12 in urine and 18 in feces. The main Ⅰ and Ⅱ phase metabolic processes involved glucuronidation, oxidation, carbonylation, (de)methylation, sulfation and hydrogenation. CONCLUSION: TED could be rapidly absorbed into the blood circulation and widely distributed and slowly metabolized in the body and underwent extensive cleavage and metabolic transformation in vivo. The study provided a basis for in-depth elucidation of the toxicology and mechanism research of TED, but also laid the foundation for further research on the material basis of hepatotoxicity of PM.

[Simultaneous determination of monochloropropanediol esters and glycidyl esters in vegetable oils by acidic transesterification-gas chromatography-mass spectrometry].

A comprehensive analytical method based on gas chromatography-mass spectrometry (GC-MS) was developed for the determination of 3-monochloropropanediol esters, 2-monochloropropanediol esters, and glycidyl esters in vegetable oils. Different parameters, such as bromination reaction temperature, bromination reaction time, derivatization reagent dosage, and derivative reaction time, were studied. The optimal conditions were as follows: 0.25 g of oil was weighed in a 10-mL glass tube, followed by the addition of 2 mL tetrahydrofuran, 25 µL of internal working standard solutions, and 30 µL of acid aqueous solution of NaBr, homogenized, and the mixture was incubated at 50 ℃ for 15 min. The reaction was stopped by the addition of 3 mL of an aqueous solution of sodium hydrogen carbonate. To separate the oil from the water phase, n-heptane was added, and the upper layer was transferred to an empty test tube and evaporated to dryness under a nitrogen stream. The residue was dissolved in 1 mL of tetrahydrofuran. 1.8 mL of sulfuric acid solution in methanol was added to the sample, and the resulting mixture was incubated at 40 ℃ for 16 h. The reaction was stopped by the addition of 0.5 mL of an aqueous solution of sodium hydrogen carbonate. After purification by n-hexane and derivatization of phenylboric acid, the derivatives were extracted with n-hexane. After nitrogen blowing, the residue was dissolved in 1 mL of n-hexane, and then filtered through a 0.45-µm membrane filter unit prior to GC-MS analysis. Temperature programming was applied at an initial temperature of 80 ℃. After 0.5 min, the temperature was raised to 180 ℃ at a rate of 20 ℃/min, held for 0.5 min, raised to 200 ℃ at a rate of 5 ℃/min for 4 min, and finally raised to 300 ℃ at a rate of 40 ℃/min for 4 min. The target compounds were separated on a DB-5MS column (30 m×0.25 mm×1 µm). Identification and quantification were achieved using an electron impact (EI) ion source in the positive ion mode with the selected ion monitoring mode. The internal standard method was used to quantify the 3-chloropropanediol esters, 2-chloropropanediol esters, and glycidyl esters. Under the optimal conditions, the correlation coefficients of the standard calibration curves were greater than 0.999 in the mass concentration range of 0.01-0.80 mg/L. The limits of detection were 25, 25, and 20 µg/kg (S/N=3), and the limits of quantification were 75, 75, 60 µg/kg (S/N=10). Four samples of different matrix types were selected for scaling experiments. At spiked levels of 250, 500, and 750 µg/kg, the recoveries of 3-chloropropanediol esters, 2-chloropropanediol esters, and glycidyl esters in spiked samples ranged from 89.0% to 98.7%, with relative standard deviations between 2.05% and 7.81% (n=6). This method was used to determine 112 commercially available vegetable oil samples, among which 84 samples were detected with 3-chloropropanediol esters, 2-chloropropanediol esters, or glycidyl esters. The method developed in this study was remarkably different from the standard method, which are mentioned in the national standard method (GB 5009.191-2016) and industry standard method (SN/T 5220-2019), especially in the pretreatment step that involved acidic transesterification. Use of the acidic transesterification method can avoid side reactions, such as the conversion of 3-chloropropanediol, 2-chloropropanediol, and 3-bromopropanediol to free glycidol under alkaline conditions. The method developed in this study was more efficient, and the results were more accurate and reproducible. It has theoretical and practical significance for the control of 3-chloropropanediol esters, 2-chloropropanediol esters, and glycidyl esters residues in vegetable oils, establishment of detection standards, and optimization of the production process.

Dendrobium nobile Lindl. alkaloids alleviate Mn-induced neurotoxicity via PINK1/Parkin-mediated mitophagy in PC12 cells.

Modern pharmacological studies have demonstrated that Dendrobium nobile Lindl. Alkaloids (DNLA), the main active ingredients of Dendrobium nobile, is valuable as an anti-aging and neuroprotective herbal medicine. The present study was designed to determine whether DNLA confers protective function over neurotoxicant manganese (Mn)-induced cytotoxicity and the mechanism involved. Our results showed that pretreatment of PC12 cells with DNLA alleviated cell toxicity induced by Mn and improved mitochondrial respiratory capacity and oxidative status. Mn treatment increased apoptotic cell death along with a marked increase in the protein expression of Bax and a decrease in the expression of Bcl-2 protein, all of which were noticeably reversed by DNLA. Furthermore, DNLA significantly abolished the decrease in protein levels of both PINK1 and Parkin, and mitigated the increased expression of autophagy marker LC3-II and accumulation of p62 caused by Mn. These results demonstrate that DNLA inhibits Mn induced cytotoxicity, which may be mediated through modulating PINK1/Parkin-mediated autophagic flux and improving mitochondrial function.

Multi-omics analysis defines 5-fluorouracil drug resistance in 3D HeLa carcinoma cell model.

Cervical cancer is a serious health problem in women around the globe. However, the use of clinical drug is seriously dampened by the development of drug resistance. Efficient in vitro tumor model is essential to improve the efficiency of drug screening and the accuracy of clinical application. Multicellular tumor spheroids (MTSs) can in a way recapitulates tumor traits in vivo, thereby representing a powerful transitional model between 2D monolayer culture and xenograft. In this study, based on the liquid overlay method, a protocol for rapid generation of the MTSs with uniform size and high reproducibility in a high-throughput manner was established. As expected, the cytotoxicity results showed that there was enhanced 5-fluorouracil (5-FU) resistance of HeLa carcinoma cells in 3D MTSs than 2D monolayer culture with a resistance index of 5.72. In order to obtain a holistic view of the molecular mechanisms that drive 5-FU resistance in 3D HeLa carcinoma cells, a multi-omics study was applied to discover hidden biological regularities. It was observed that in the 3D MTSs mitochondrial function-related proteins and the metabolites of the tricarboxylic acid cycle (TCA cycle) were significantly decreased, and the cellular metabolism was shifted towards glycolysis. The differences in the protein synthesis, processing, and transportation between 2D monolayer cultures and 3D MTSs were significant, mainly in the heat shock protein family, with the up-regulation of protein folding function in endoplasmic reticulum (ER), which promoted the maintenance of ER homeostasis in the 3D MTSs. In addition, at the transcript and protein level, the expression of extracellular matrix (ECM) proteins (e.g., laminin and collagen) were up-regulated in the 3D MTSs, which enhanced the physical barrier of drug penetration. Summarizing, this study formulates a rapid, scalable and reproducible in vitro model of 3D MTS for drug screening purposes, and the findings establish a critical role of glycolytic metabolism, ER hemostasis and ECM proteins expression profiling in tumor chemoresistance of HeLa carcinoma cells towards 5-FU.

Alpha 1-antitrypsin for treating ventilator-associated lung injury in acute respiratory distress syndrome rats.

Purpose: Mechanical ventilation (MV) is an essential life support tool for patients with acute respiratory distress syndrome (ARDS). However, MV for ARDS can result in ventilator-induced lung injury (VILI). This study aimed to assess whether alpha 1-antitrypsin (AAT) can reduce VILI in ARDS rats. Materials and Methods: Rats were randomly divided into five groups: the sham (S) group, MV (V) group, lipopolysaccharide (LPS) (L) group, MV/LPS (VL) group and MV/AAT (VA) group. Rats in the S group were anesthetized. The rats in the L group received LPS but not ventilation, the rats in the V group received only MV, and the rats in the VL and VA groups received LPS and MV. Additionally, the rats in the VA group were treated with AAT, and the other rats were injected with saline. The PaO2/FiO2 ratio and the wet/dry weight were assessed. The total protein and neutrophil elastase concentrations and the neutrophil and macrophage counts in bronchoalveolar lavage fluid (BALF) were evaluated. Proinflammatory factors in BALF and ICAM-1 and MIP-2 in serum were also tested. Furthermore, the oxidative stress response was detected, and histological injury and apoptosis were evaluated. Results: All the rats in the V, L and VL groups had significant lung injury, with the VL group exhibiting the most severe injury. Compared with the findings in the VL group, AAT significantly upregulated the PaO2/FiO2 ratio but decreased the wet/dry weight ratio and protein levels in BALF. AAT also reduced proinflammatory cytokine levels and inflammatory cell counts in BALF. Lung tissue injury and cell apoptosis were mitigated by AAT. Conclusions: AAT ameliorated VILI in ARDS rats. The protection conferred by AAT may be associated with the anti-inflammatory, antioxidative stress response and anti-apoptotic effects of AAT.