China
Africa
Explore chapters and articles related to this topic
Metallopharmaceuticals
Published in Varma H. Rambaran, Nalini K. Singh, Alternative Medicines for Diabetes Management, 2023
Varma H. Rambaran, Nalini K. Singh
Molybdenum is classified as a second-row transition metal with the symbol Mo and atomic number 42 (Figure 4.17). It is an essential mineral that is found in high concentrations in legumes, grains, and organ meats, and is considered essential for human life (Rowles 2017). Like the tungstate ion, molybdate is a compound containing an oxo-anion with Mo in its highest oxidation state of 6 (Figure 4.18).Structure of molybdate.
Molybdenum cofactor deficiency
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
Therapy with molybdate has been employed without success. However, none of the patients treated were defined at the molecular level; it is likely that they represented MOCS1 or 2 mutations. A patient with gephyrin deficiency might be different, but synaptic abnormalities resulting from the receptor clustering effect of this gene makes it less likely.
Registrations of Geochemical Compositions of Soils, Plants, and Waters as a Basis for Geomedical Investigations in Finland
Published in Jul Låg, Geomedicine, 2017
Molybdenum occurs in igneous and metamorphic rocks, mainly as disseminated sufides, with the highest concentrations in granitoids and various schists. Molybdenum is released during weathering and oxidized into mobile molybdate ions. It tends to be adsorbed on sesquioxides and clay minerals and, as it behaves differently from all other trace metals is most soluble in an alkaline environment (see, e.g., Reference 18). Molybdenum plays a major role in enhancing plant growth, although its role in animal and human metabolism and health is not fully understood. The geochemical maps do not reveal any consistent anomalous geochemical regions. Only in heavy minerals do the anomalous Mo contents seem to be concentrated in granitoid areas, while till and minerogenic stream sediments show higher contents in silicic and subsilicic rock areas without any systematic distribution pattern.
Ginkgo biloba leaves extract’s cosmeceutical evaluation: a preliminary assessments on human volunteers towards achieving improved skin condition and rejuvenation
Published in Drug Development and Industrial Pharmacy, 2023
Ahmed A. H. Abdellatif, Hamdoon A. Mohammed, Ali M. Al-Khalaf, Omar Khan, Mahmoud A. H. Mostafa, Rwaida A. Al Haidari, Hesham H. Taha, Riaz A. Khan
The antioxidant potentials of the GB extract and GB cream were estimated at the same concentrations. A 0.5 g of the cream containing 2% of the GB extract was digested in 1 ml of ethanol, and similar weight, 0.5 g of the 2% GB extract was also diluted with 1 ml of ethanol to a prepared equivalent concentration of the cream and extract. Molybdate reagent was prepared by mixing sulfuric acid (0.6 M) and ammonium molybdate (4 mM) in sodium phosphate buffer (28 mM). Accurately, 3.6 ml of the molybdate reagent was added to 100 µl of the samples, and the mixture was vortexed and kept on a water bath for 30 min. The mixture was then allowed to cool at room temperature, and the absorbance was recorded at 695 nm using a spectrophotometer against a blank. The total antioxidant activity of the extract was calculated equivalent to the TROLOX using the standard calibration curve from the equation: y = 0.1954x − 0.1788; R2 = 0.9646, where y is the absorbance of the sample at 695 nm and x is the concentration of the sample in µg/ml. The plant extract showed 5.64 ± 0.7 µg/ml, while the cream showed 5.34 ± 0.15 µg/ml of the Molybdate reduction strength.
Comparative outcomes of exposing human liver and kidney cell lines to tungstate and molybdate
Published in Toxicology Mechanisms and Methods, 2021
Sherry Sachdeva, Wolfgang Maret
Like many essential elements at higher concentrations, molybdenum in the form of molybdate can be toxic as well (Zhuang et al. 2021). Historically, molybdosis was found in ruminants grazing on molybdenum-rich soils. The toxicity is due to a syndrome of secondary copper deficiency because molybdate is transformed into tetrathiomolybdate in the sulfur-rich environment of the ruminant digestive tract and tetrathiomolybdate binds copper strongly. In goats receiving an excessive amount of heptamolybdate in the drinking water, oxidative damage in kidney mitochondria was observed and linked to a secondary copper deficiency (Feng et al. 2020). Molybdenum seems to be less toxic to humans compared to ruminants, but there is evidence from human balance studies that relatively low amounts of dietary molybdenum affect copper metabolism, suggesting that diets rich in molybdenum can lead to copper deficiency (Deosthale and Gopalan 1974; Underwood 1977). Whether tungsten has a similar effect on copper metabolism is not known. A crystal structure of a copper chaperone binding to molybdate has been determined and suggests that molybdate interferes with copper trafficking proteins (Alvarez et al. 2010). If such a complex with copper chaperones forms in humans upon exposure to either molybdate or tungstate, it could tie up the copper chaperone for superoxide dismutase and not deliver copper to superoxide dismutase for its activity, resulting in oxidative stress.
Surface atomic arrangement of nanomaterials affects nanotoxicity
Published in Nanotoxicology, 2021
Kaiwen Li, Zhongwei Wang, Hui Zeng, Jing Sun, Yue Wang, Qixing Zhou, Xiangang Hu
As shown in Figure S7, the ionic release from MoS2 nanosheets was significantly higher in E3 medium than in deionized water, implying the occurrence of ion exchange. At 96 h, approximately 27.3 and 30.68% of Mo was released from 1 T-MoS2 and 2H-MoS2, respectively. The molar ratio of S/Mo of MoS2 nanosheets in E3 medium was greater than 2 (Table S2), which might attribute to that MoS2 nanosheet can be oxidized by O2 to MoO42- in E3 medium causing the loss of Mo in MoS2 nanosheets (Zou et al. 2019). Moreover, the HRTEM image and EDS spectrum showed that the contents of Na element in 1 T-MoS2 and 2H-MoS2 nanosheets were higher in E3 media than those in deionized water (Figure S8). The results were consistent with the previous studies that high content of Na+ in biological medium (e.g., E3 medium) led to the formation of Na2S, accelerating the degradation process of MoS2 nanosheets and promoting the release of Mo4+ (Chen et al. 2018). Given the obvious release of Mo from the nanosheets in culture medium, the adverse effects of the released Mo ions should not be neglected. Na2MoO4 was chosen to study the toxic effects of Mo ions on zebrafish embryos. As shown in Figure S9, compared to the control, molybdate did not induce obvious mortality, hatching delay, malformation, mitochondrial membrane potential loss or ROS level increase, indicating that the nanotoxicity originated from the nanosheets rather than the released ions.