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Molecules (Basel, Switzerland) Nov 2023The pyranopterin dithiolene ligand is remarkable in terms of its geometric and electronic structure and is uniquely found in mononuclear molybdenum and tungsten enzymes.... (Review)
Review
The pyranopterin dithiolene ligand is remarkable in terms of its geometric and electronic structure and is uniquely found in mononuclear molybdenum and tungsten enzymes. The pyranopterin dithiolene is found coordinated to the metal ion, deeply buried within the protein, and non-covalently attached to the protein via an extensive hydrogen bonding network that is enzyme-specific. However, the function of pyranopterin dithiolene in enzymatic catalysis has been difficult to determine. This focused account aims to provide an overview of what has been learned from the study of pyranopterin dithiolene model complexes of molybdenum and how these results relate to the enzyme systems. This work begins with a summary of what is known about the pyranopterin dithiolene ligand in the enzymes. We then introduce the development of inorganic small molecule complexes that model aspects of a coordinated pyranopterin dithiolene and discuss the results of detailed physical studies of the models by electronic absorption, resonance Raman, X-ray absorption and NMR spectroscopies, cyclic voltammetry, X-ray crystallography, and chemical reactivity.
Topics: Models, Molecular; Molybdenum; Ligands; Metalloproteins; Catalysis; Coenzymes
PubMed: 38005178
DOI: 10.3390/molecules28227456 -
Environmental Pollution (Barking, Essex... Oct 2023Molybdenum (Mo) is an essential trace element that exists in all tissues of the human body, but excessive Mo intake has a toxic effect. Cadmium (Cd) is a widely known...
Molybdenum (Mo) is an essential trace element that exists in all tissues of the human body, but excessive Mo intake has a toxic effect. Cadmium (Cd) is a widely known and harmful heavy metal that exists in the environment. Although studies on Mo and Cd are available, it is still unknown how the combination of Mo and Cd causes pulmonary injury. Forty-eight sheep that were 2 months old were chosen and randomly separated into four groups as follows: Control group, Mo group, Cd group, and Mo + Cd group. The experiment lasted 50 days. The results showed that Mo and/or Cd caused significant pathological damage and oxidative stress in the lungs of sheep. Moreover, Mo and/or Cd exposure could downregulate the expression levels of xCT (SLC7A11 and SLC3A2), GPX4 and FTH-1 and upregulate the expression levels of PTGS2 and NCOA4, which led to iron overload and ferroptosis. Ferroptosis induced Wnt/β-catenin-mediated fibrosis by elevating the expression levels of Caveolin-1 (CAV-1), Wnt 1, Wnt3a, β-catenin (CTNNB1), TCF4, Cyclin D1, mmp7, α-SMA (ACTA2), Collagen 1 (COL1A1) and Vimentin. These changes were particularly noticeable in the Mo and Cd combination group. In conclusion, these data demonstrated that Mo and/or Cd exposure led to lung ferroptosis by inhibiting the SLC7A11/GSH/GPX4 axis, which in turn increases CAV-1 expression and subsequently activates the Wnt/β-catenin pathway, leading to fibrosis in sheep lungs.
Topics: Humans; Animals; Sheep; Infant; Molybdenum; Cadmium; beta Catenin; Ferroptosis; Caveolin 1; Fibrosis; Lung
PubMed: 37467914
DOI: 10.1016/j.envpol.2023.122207 -
Nanoscale Sep 2023Electrocatalytic hydrogen evolution reaction (HER) is one of the most promising and clean strategies to prepare hydrogen on a large scale. Nevertheless, the efficiency... (Review)
Review
Electrocatalytic hydrogen evolution reaction (HER) is one of the most promising and clean strategies to prepare hydrogen on a large scale. Nevertheless, the efficiency of HER is greatly restricted by the large overpotential at the anode, and it is necessary to develop low cost electrocatalysts with excellent performance and stability. Molybdenum carbide has shown great potential in the field of HER due to its unique electronic structure and physical and chemical properties. In this paper, the current progress of molybdenum carbide-based catalysts for HER is summarized. The influence of phase structure, nanostructure, heterostructure and heteroatoms doping on its catalytic performance is discussed in detail. Especially, the catalytic mechanisms are analyzed according to structural characterization and theoretical calculation results. Finally, the challenges and prospects for the further development of molybdenum carbide-based catalysts for HER are put forward to guide the progress of this field.
PubMed: 37655752
DOI: 10.1039/d3nr02511j -
Advanced Science (Weinheim,... Jun 2024Metal borides have received a lot of attention recently as a potentially useful material for a wide range of applications. In particular, molybdenum-based borides and... (Review)
Review
Metal borides have received a lot of attention recently as a potentially useful material for a wide range of applications. In particular, molybdenum-based borides and MBenes are of great significance, due to their remarkable properties like good electronic conductivity, considerable stability, high surface area, and environmental harmlessness. Therefore, in this article, the progress made in molybdenum-based borides and MBenes in recent years is reviewed. The first step in understanding these materials is to begin with an overview of their structural and electronic properties. Then synthetic technologies for the production of molybdenum borides, such as high-temperature/pressure methods, physical vapor deposition (PVD), chemical vapor deposition (CVD), element reaction route, molten salt-assisted, and selective etching methods are surveyed. Then, the critical performance of these materials in numerous applications like energy storage, catalysis, biosensors, biomedical devices, surface-enhanced Raman spectroscopy (SERS), and tribology and lubrication are summarized. The review concludes with an analysis of the current progress of these materials and provides perspectives for future research. Overall, this review will offer an insightful reference for the understanding molybdenum-based borides and their development in the future.
PubMed: 38526182
DOI: 10.1002/advs.202308178 -
Biosensors Nov 2023Azithromycin (AZY) is a well-known top-prioritized antibiotic and is used by humans in strong concentrations. However, the side effects of the AZY antibiotic may cause...
Azithromycin (AZY) is a well-known top-prioritized antibiotic and is used by humans in strong concentrations. However, the side effects of the AZY antibiotic may cause some serious and significant damage to humans and the environment. Thus, there is a need to develop effective and sensitive sensors to monitor accurate concentrations of AZY. In the last decade, electrochemistry-based sensors have received enormous attention from the scientific community because of their high sensitivity, selectivity, cost-effectiveness, fast response, rapid detection response, simple fabrication, and working principle. It is important to mention that electrochemical sensors rely on the properties of electrode modifiers. Hence, the selection of electrode materials is of great significance when designing and developing efficient and robust electrochemical sensors. In this study, we fabricated an AZY sensor by utilizing a molybdenum disulfide/titanium aluminum carbide (MoS@TiAlC) composite as the electrode material. The MoS@TiAlC composite was synthesized via a simple sonication process. The synthesized MoS@TiAlC composite was characterized using a powder X-ray diffraction (XRD) method to examine the phase purity and formation of the MoS@TiAlC composite. Scanning electron microscopy (SEM) was used to study the surface morphological features of the prepared MoS@TiAlC composite, whereas energy dispersive X-ray spectroscopy (EDAX) was adopted to determine the elemental composition of the prepared MoS@TiAlC composite. The glassy carbon (GC) electrode was modified with the prepared MoS@TiAlC composite and applied as the AZY sensor. The sensing performance of the MoS@TiAlC composite-modified GC electrode was studied using linear sweep voltammetry. The sensor demonstrated excellent performance when determining AZY and showed a good detection limit of 0.009 µM with a sensitivity of 6.77 µA/µM.cm.
Topics: Humans; Molybdenum; Azithromycin; Carbon; Microscopy, Electron, Scanning; Anti-Bacterial Agents; Electrodes; Limit of Detection; Electrochemical Techniques
PubMed: 37998161
DOI: 10.3390/bios13110986 -
Food & Nutrition Research 2023Molybdenum is an essential element in the form of the molybdenum cofactor (Moco). In humans, Moco is required for four enzymes: xanthine oxidase (XO), aldehyde oxidase,... (Review)
Review
Molybdenum is an essential element in the form of the molybdenum cofactor (Moco). In humans, Moco is required for four enzymes: xanthine oxidase (XO), aldehyde oxidase, sulfite oxidase (SO), and mitochondrial amidoxime-reducing component (mARC). The enzymes are involved in the oxidation of purines to uric acid, metabolism of aromatic aldehydes and heterocyclic compounds, and in the catabolism of sulfur amino acids. Molybdenum cofactor deficiency is a rare autosomal recessive syndrome due to a defective synthesis of Moco, resulting in a deficiency of all the molybdoenzymes. There are no reports on clinical signs of dietary molybdenum deficiency in otherwise healthy humans. Water-soluble molybdate is efficiently absorbed from the digestive tract. The body retention is regulated by urinary excretion. Plasma molybdenum reflects long-term intake and 24-h urinary excretion is related to recent intake. There are no biochemical markers of molybdenum status. Cereal products are the main contributors to molybdenum dietary intake, estimated to 100-170 μg/day in Nordic studies. Little data are available on molybdenum toxicity in humans. A tolerable upper intake level of molybdenum has been based on reproductive toxicity in rats, but the effects have not been reproduced in more recent studies. The U.S. Institute of Medicine (IOM, present National Academy of Sciences, Engineering, and Medicine; NASEM) established a Recommended Dietary Allowance of 45 μg/day in adult men and women in 2001, based on a small study reporting urinary excretion in balance with intake at 22 μg/day. The European Food Safety Authority (EFSA) considered in 2013 the evidence to be insufficient to derive an Average Requirement and a Population Reference Intake, but proposed an Adequate Intake of 65 μg/day for adults.
PubMed: 38187804
DOI: 10.29219/fnr.v67.10326 -
Advanced Science (Weinheim,... Sep 2023Sonodynamic therapy (SDT) has been widely reported as a noninvasive and high-penetration therapy for cancer; however, the design of an efficient sonosensitizer remains...
Sonodynamic therapy (SDT) has been widely reported as a noninvasive and high-penetration therapy for cancer; however, the design of an efficient sonosensitizer remains an urgent need. To address this issue, molybdenum disulfide nanoflowers (MoS NF) as piezo-sonosensitizers and introduced sulfur vacancies on the MoS NF (Sv-MoS NF) to improve their piezoelectric property for cancer therapy are designed. Under ultrasonic mechanical stress, the Sv-MoS NF resulted in piezoelectric polarization and band tilting, which enhanced the charge carrier separation and migration. This resulted in an improved catalytic reaction for reactive oxygen species (ROS) production, ultimately enhancing the SDT performance. Thanks to the high efficiency of ROS generation, the Sv-MoS NF have demonstrated a good anticancer effect in vitro and in vivo. Following a systematic evaluation, Sv-MoS NF also demonstrated good biocompatibility. This novel piezo-sonosensitizer and vacancy engineering strategy provides a promising new approach for achieving efficient SDT.
Topics: Humans; Molybdenum; Reactive Oxygen Species; Ultrasonic Therapy; Neoplasms
PubMed: 37395638
DOI: 10.1002/advs.202301152 -
Advanced Science (Weinheim,... Aug 2023Increased levels of circulating cell-free DNA (cfDNA) are associated with poor clinical outcomes in patients with acute kidney injury (AKI). Scavenging cfDNA by...
Increased levels of circulating cell-free DNA (cfDNA) are associated with poor clinical outcomes in patients with acute kidney injury (AKI). Scavenging cfDNA by nanomaterials is regarded as a promising remedy for cfDNA-associated diseases, but a nanomaterial-based cfDNA scavenging strategy has not yet been reported for AKI treatment. Herein, polyglycerol-amine (PGA)-covered MoS nanosheets with suitable size are synthesized to bind negatively charged cfDNA in vitro, in vivo and ex vivo models. The nanosheets exhibit higher cfDNA binding capacity than polymer PGA and PGA-based nanospheres owing to the flexibility and crimpability of their 2D backbone. Moreover, with low cytotoxicity and mild protein adsorption, the nanosheets effectively reduced serum cfDNA levels and predominantly accumulated in the kidneys to inhibit the formation of neutrophil extracellular traps and renal inflammation, thereby alleviating both lipopolysaccharide and ischemia-reperfusion induced AKI in mice. Further, they decreased the serum cfDNA levels in samples from AKI patients. Thus, PGA-covered MoS nanosheets can serve as a potent cfDNA scavenger for treating AKI and other cfDNA-associated diseases. In addition, this work demonstrates the pivotal feature of a 2D sheet-like structure in the development of the cfDNA scavenger, which can provide a new insight into the future design of nanoplatforms for modulating inflammation.
Topics: Mice; Animals; Cell-Free Nucleic Acids; Molybdenum; Acute Kidney Injury; Inflammation; Amines
PubMed: 37276385
DOI: 10.1002/advs.202300604 -
Chemico-biological Interactions Sep 2023Accumulation of the heavy metals molybdenum (Mo) and cadmium (Cd) in the liver can induce organelle damage and inflammation, resulting in hepatotoxicity. The effect of...
Accumulation of the heavy metals molybdenum (Mo) and cadmium (Cd) in the liver can induce organelle damage and inflammation, resulting in hepatotoxicity. The effect of Mo and/or Cd on sheep hepatocytes was investigated by determining the relationship between the mitochondria-associated endoplasmic reticulum membrane (MAM) and NLRP3 inflammasome. Sheep hepatocytes were divided into four groups: the control group, Mo group (600 μM Mo), Cd group (4 μM Cd) and Mo + Cd group (600 μM Mo+4 μM Cd). The results showed that Mo and/or Cd exposure increased the levels of lactate dehydrogenase (LDH) and nitric oxide (NO) in the cell culture supernatant, elevated the levels of intracellular Ca and mitochondrial Ca, downregulated the expression of MAM-related factors (IP3R, GRP75, VDAC1, PERK, ERO1-α, Mfn1, Mfn2, ERP44), shortened the length of the MAM and reduced the formation of the MAM structure, eventually causing MAM dysfunction. Moreover, the expression levels of NLRP3 inflammasome-related factors (NLRP3, Caspase1, IL-1β, IL-6, TNF-α) were also dramatically increased after Mo and Cd exposure, triggering NLRP3 inflammasome production. However, an IP3R inhibitor, 2-APB treatment significantly alleviated these changes. Overall, the data indicate that Mo and Cd coexposure leads to structural disruption and dysfunction of MAM, disrupts cellular Ca homeostasis, and increases NLRP3 inflammasome production in sheep hepatocytes. However, the inhibition of IP3R alleviates NLRP3 inflammasome production induced by Mo and Cd.
Topics: Animals; Sheep; Inflammasomes; NLR Family, Pyrin Domain-Containing 3 Protein; Cadmium; Molybdenum; Hepatocytes; Endoplasmic Reticulum; Mitochondria
PubMed: 37385403
DOI: 10.1016/j.cbi.2023.110617 -
Environmental Science and Pollution... Oct 2023Some heavy metals are associated with periodontitis; whereas most of these associations have focused on individual metal, there are no specific studies on the effects of...
Some heavy metals are associated with periodontitis; whereas most of these associations have focused on individual metal, there are no specific studies on the effects of combined heavy metal exposure on periodontitis. We conducted an analysis on the association between urinary heavy metal exposure and periodontitis in participants aged 30 years and older using multiple logistic regression and Bayesian kernel machine regression (BKMR). This analysis was performed on data from the National Health and Nutrition Examination Survey from 2011 to 2014. The study found that using logistic regression, the 4th quartile of urinary lead and molybdenum and the 3rd quartile of urinary strontium were positively associated with periodontitis compared to the reference quartile after adjusting for covariates. Odds ratio (OR) with 95% confidence interval (CI) was 1.738 (1.069-2.826), 1.515 (1.025-2.239), and 1.498 (1.010-2.222), respectively. The 3rd and 4th quartiles of urinary cobalt were negatively associated with periodontitis, and their ORs and 95% CIs were 0.639 (0.438-0.934) and 0.571 (0.377-0.964), respectively. The BKMR model showed that urinary barium, lead, and molybdenum were positively associated with periodontitis in a range of concentrations and urinary cobalt, manganese, tin, and strontium were negatively correlated with periodontitis. Furthermore, the overall association between urinary heavy metals and periodontitis was positive. Our study provides evidence for an association between exposure to multiple urinary heavy metals and periodontitis. However, further longitudinal studies are needed to explore the specific mechanisms involved.
Topics: Adult; Humans; Nutrition Surveys; Molybdenum; Bayes Theorem; Metals, Heavy; Cobalt; Periodontitis; Strontium; Cadmium
PubMed: 37740806
DOI: 10.1007/s11356-023-29888-6