RESUMO
Accurate detection of endogenous miRNA modifications, such as N6-methyladenosine (m6A), 7-methylguanosine (m7G), and 5-methylcytidine (m5C), poses significant challenges, resulting in considerable uncertainty regarding their presence in mature miRNAs. In this study, we demonstrate for the first time that liquid chromatography coupled with a tandem mass spectrometry (LC-MS/MS) nucleoside analysis method is a practical tool for quantitatively analyzing human miRNA modifications. The newly designed liquid-solid two-step hybridization (LSTH) strategy enhances specificity for miRNA purification, while LC-MS/MS offers robust capability in recognizing modifications and sufficient sensitivity with detection limits ranging from attomoles to low femtomoles. Therefore, it provides a more reliable approach compared to existing techniques for revealing modifications in endogenous miRNAs. With this approach, we characterized m6A, m7G, and m5C modifications in miR-21-5p, Let-7a/e-5p, and miR-10a-5p isolated from cultured cells and observed unexpectedly low abundance (<1% at each site) of these modifications.
Assuntos
Adenosina , Citidina , Guanosina , MicroRNAs , Humanos , Adenosina/análogos & derivados , Adenosina/análise , Citidina/análogos & derivados , Guanosina/análogos & derivados , Guanosina/análise , Espectrometria de Massa com Cromatografia Líquida , MicroRNAs/análise , Hibridização de Ácido Nucleico , Espectrometria de Massas em TandemRESUMO
Sulfur mustard (SM) is a highly toxic blister agent which has been used many times in several wars and conflicts and caused heavy casualties. Ease of production and lack of effective therapies make SM a potential threat to public health. SM intoxication causes severe damage on various target organs, such as the skin, eyes, and lungs. In addition, SM exposure can also lead to hepatotoxicity and severe liver injuries. However, despite decades of research, the molecular mechanism underlying SM-induced liver damage remains obscure. SM can be converted into various products via complex hepatic metabolism in vivo. There are some pieces of evidence that one of the oxidation products of SM, divinyl sulfone (DVS), exhibits even more significant toxicity than SM. Nevertheless, the molecular toxicology of DVS is still hardly known. In the present study, we confirmed that DVS is even more toxic than SM in the human hepatocellular carcinoma cell line HepG2. Further mechanistic study revealed that DVS exposure (200 µM) promotes pyroptosis in HepG2 cells, while SM (400 µM) mainly induces apoptosis. DVS induces gasdermin D (GSDMD) mediated pyroptosis, which is independent of caspases activation but depends on the large amounts of reactive oxygen species (ROS) and severe oxidative stress produced during DVS exposure. Our findings may provide novel insights for understanding the mechanism of SM poisoning and may be helpful to discover promising therapeutic strategies for SM intoxication.
Assuntos
Substâncias para a Guerra Química , Gás de Mostarda , Sulfonas , Humanos , Gás de Mostarda/toxicidade , Caspases/metabolismo , Piroptose , Hepatócitos , Estresse Oxidativo , Substâncias para a Guerra Química/metabolismoRESUMO
Genotoxic substances widely exist in the environment and the food supply, posing serious health risks due to their potential to induce DNA damage and cancer. Traditional genotoxicity assays, while valuable, are limited by insufficient sensitivity, specificity, and efficiency, particularly when applied to complex food matrices. This study introduces a multiparametric high-content analysis (HCA) for the detection of genotoxic substances in complex food matrices. The developed assay measures three genotoxic biomarkers, including γ-H2AX, p-H3, and RAD51, which enhances the sensitivity and accuracy of genotoxicity screening. Moreover, the assay effectively distinguishes genotoxic compounds with different modes of action, which not only offers a more comprehensive assessment of DNA damage and the cellular response to genotoxic stress but also provides new insights into the exploration of genotoxicity mechanisms. Notably, the five tested food matrices, including coffee, tea, pak choi, spinach, and tomato, were found not to interfere with the detection of these biomarkers under proper dilution ratios, validating the robustness and reliability of the assay for the screening of genotoxic compounds in the food industry. The integration of multiple biomarkers with HCA provides an efficient method for detecting and assessing genotoxic substances in the food supply, with potential applications in toxicology research and food safety.
Assuntos
Dano ao DNA , Testes de Mutagenicidade , Mutagênicos , Mutagênicos/análise , Mutagênicos/toxicidade , Testes de Mutagenicidade/métodos , Humanos , Análise de Alimentos/métodos , Chá/química , Biomarcadores , Solanum lycopersicum/química , Histonas/metabolismo , Histonas/análise , Café/química , Spinacia oleracea/química , Rad51 Recombinase/metabolismoRESUMO
The data for the effect of dietary magnesium (Mg) on hemoglobin glycation index (HGI) is limited. Thus, this study aimed to examine the relationship between dietary Mg and HGI in the general population. Our research used data from the National Health and Nutrition Examination Survey from 2001 to 2002. The dietary intake of Mg was assessed by two 24-h dietary recalls. The predicted HbA1c was calculated based on fasting plasma glucose. Logistic regression and restricted cubic spline models were applied to assess the relationship between dietary Mg intake and HGI. We found a significant inverse association between dietary Mg intake and HGI (ß = - 0.00016, 95%CI: - 0.0003, - 0.00003, P = 0.019). Dose-response analyses revealed that HGI decreased with increasing intakes of Mg when reached the point above 412 mg/day. There was a linear dose-response relationship between dietary Mg intake and HGI in diabetic subjects, and there was an L-shape dose-response relationship in non-diabetic individuals. Increasing the intake of Mg might help lower the risk associated with high HGI. Further prospective studies are requested before dietary recommendations.
Assuntos
Diabetes Mellitus Tipo 2 , Magnésio , Humanos , Hemoglobinas Glicadas , Estudos Prospectivos , Reação de Maillard , Inquéritos Nutricionais , HemoglobinasRESUMO
Background: This investigation sought to elucidate the correlations between alcohol intake and trajectories of fasting blood glucose (FBG) among American women in midlife. Methods: Our analysis was rooted in the foundational data from the Study of Women's Health Across the Nation (SWAN), a comprehensive longitudinal study centered on US women during their midlife transition. We employed group-based trajectory modeling to chart the FBG trajectories spanning from 1996 to 2005. Employing logistic regression, we gauged the odds ratios (ORs) and 95% confidence intervals (CIs) to draw connections between initial alcohol consumption and FBG trajectory patterns, whilst controlling for predominant potential confounders. Results: Our cohort comprised 2,578 women in midlife, ranging in age from 42 to 52, each having a minimum of three subsequent FPG assessments. We discerned two distinct FBG trajectories: a low-stable pattern (n = 2,467) and a high-decreasing pattern (n = 111). Contrasted with the low-stable group, our data showcased an inverse relationship between alcohol intake and the high-decreasing FBG trajectory in the fully adjusted model 3. The most pronounced reduction was evident in the highest tertile of daily servings of alcoholic beverages (OR: 0.23, 95% CI: 0.10-0.52, p < 0.001), percentage of kilocalories sourced from alcoholic beverages (OR: 0.30, 95% CI: 0.16-0.58, p < 0.001), and daily caloric intake from alcoholic beverages (OR: 0.31, 95% CI: 0.16-0.62, p < 0.001). Conclusion: Moderate alcohol consumption may protect against high FPG trajectories in middle-aged women in a dose-response manner. Further researches are needed to investigate this causality in midlife women.
Assuntos
Consumo de Bebidas Alcoólicas , Glicemia , Humanos , Pessoa de Meia-Idade , Feminino , Estados Unidos/epidemiologia , Estudos Longitudinais , Fatores de Risco , Consumo de Bebidas Alcoólicas/epidemiologia , JejumRESUMO
Amanita phalloides is one of the deadliest mushrooms worldwide, causing most fatal cases of mushroom poisoning. Among the poisonous substances of Amanita phalloides, amanitins are the most lethal toxins to humans. Currently, there are no specific antidotes available for managing amanitin poisoning and treatments are lack of efficacy. Amanitin mainly causes severe injuries to specific organs, such as the liver, stomach, and kidney, whereas the lung, heart, and brain are hardly affected. However, the molecular mechanism of this phenomenon remains not understood. To explore the possible mechanism of organ specificity of amanitin-induced toxicity, eight human cell lines derived from different organs were exposed to α, ß, and γ-amanitin at concentrations ranging from 0.3 to 100 µM. We found that the cytotoxicity of amanitin differs greatly in various cell lines, among which liver-derived HepG2, stomach-derived BGC-823, and kidney-derived HEK-293 cells are most sensitive. Further mechanistic study revealed that the variable cytotoxicity is mainly dependent on the different expression levels of the organic anion transporting polypeptide 1B3 (OATP1B3), which facilitates the internalization of amanitin into cells. Besides, knockdown of OATP1B3 in HepG2 cells prevented α-amanitin-induced cytotoxicity. These results indicated that OATP1B3 may be a crucial therapeutic target against amanitin-induced organ failure.