-
Frontiers in Cellular and Infection... 2022The central theme of this enterprise is to find common features, if any, displayed by genetically different antimony (Sb)-resistant viscerotropic parasites to impart Sb...
The central theme of this enterprise is to find common features, if any, displayed by genetically different antimony (Sb)-resistant viscerotropic parasites to impart Sb resistance. In a limited number of clinical isolates ( = 3), we studied the breadth of variation in the following dimensions: (a) intracellular thiol content, (b) cell surface expression of glycan having N-acetyl-D-galactosaminyl residue as the terminal sugar, and (c) gene expression of thiol-synthesizing enzymes (CBS, MST, gamma-GCS, ODC, and TR), antimony-reducing enzymes (TDR and ACR2), and antimonial transporter genes (AQP1, MRPA, and PRP1). One of the isolates, T5, that was genotypically characterized as , caused Indian Kala-azar and was phenotypically Sb resistant (T5-LT-SSG-R), while the other two were , out of which one isolate, AG83, is antimony sensitive (AG83-LD-SSG-S) and the other isolate, T8, is Sb resistant (T8-LD-SSG-R). Our study showed that the Sb-resistant parasites, regardless of their genotype, showed significantly higher intracellular thiol compared with Sb-sensitive AG83-LD-SSG-S. Seemingly, T5-LT-SSG-R showed about 1.9-fold higher thiol content compared with T8-LD-SSG-R which essentially mirrored cell surface N-acetyl-D-galactosaminyl expression. Except TR, the expression of the remaining thiol-synthesizing genes was significantly higher in T8-LD-SSG-R and T5-LT-SSG-R than the sensitive one, and between the Sb-resistant parasites, the latter showed a significantly higher expression. Furthermore, the genes for Sb-reducing enzymes increased significantly in resistant parasites regardless of genotype compared with the sensitive one, and between two resistant parasites, there was hardly any difference in expression. Out of three antimony transporters, AQP1 was decreased with the concurrent increase in MRPA and PRP1 in resistant isolates when compared with the sensitive counterpart. Interestingly, no difference in expression of the above-mentioned transporters was noted between two Sb-resistant isolates. The enduring image that resonated from our study is that the genetically diverse Sb-resistant parasites showed enhanced thiol-synthesizing and antimony transporter gene expression than the sensitive counterpart to confer a resistant phenotype.
Topics: Humans; Leishmaniasis, Visceral; Antimony; Antiprotozoal Agents; Drug Resistance; Membrane Transport Proteins; Sulfhydryl Compounds
PubMed: 36405965
DOI: 10.3389/fcimb.2022.1021464 -
Journal of Inorganic Biochemistry Dec 2015Antimony one of the heavier pnictogens, has been in medical use against microbes and parasites as well. Antimony-based drugs have been prescribed against leishmaniasis... (Review)
Review
Antimony one of the heavier pnictogens, has been in medical use against microbes and parasites as well. Antimony-based drugs have been prescribed against leishmaniasis since the parasitic transmission of the tropical disease was understood in the beginning of the 20th century. The activity of arsenic against visceral leishmaniasis led to the synthesis of an array of arsenic-containing parasitic agents, among them the less toxic pentavalent antimonials: Stibosan, Neostibosan, and Ureastibamine. Other antimony drugs followed: sodium stibogluconate (Pentostam) and melglumine antimoniate (Glucantim or Glucantime); both continue to be in use today despite their toxic side effects and increasing loss in potency due to the growing resistance of the parasite against antimony. Antimony compounds and their therapeutic potentials are under consideration from many research groups, while a number of early reviews recording advances of antimony biomedical applications are also available. However, there are only few reports on the screening for antitumor potential of antimony compounds. This review focuses upon results obtained on the anti-proliferative activity of antimony compounds in the past years. This survey shows that antimony(III/V) complexes containing various types of ligands such as thiones, thiosemicarbazones, dithiocarbamates, carboxylic acids, or ketones, nitrogen donor ligands, exhibit selectivity against a variety of cancer cells. The role of the ligand type of the complex is elucidated within this review. The complexes and their biological activity are already reported elsewhere. However quantitative structure-activity relationship (QSAR) modeling studies have been carried out and they are reported for the first time here.
Topics: Animals; Antimony; Antineoplastic Agents; Cell Proliferation; Humans; Organometallic Compounds; Quantitative Structure-Activity Relationship
PubMed: 26092367
DOI: 10.1016/j.jinorgbio.2015.06.006 -
Journal of Environmental Sciences... Jan 2022Soils and waters are heavily contaminated by antimony in Xikuangshan (XKS) mine area. It is widely accepted that oxidative dissolution of sulfide minerals and aqueous...
Soils and waters are heavily contaminated by antimony in Xikuangshan (XKS) mine area. It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment. Bosea sp. AS-1 is an antimonite-oxidizer isolated from the mine slag in Xikuangshan Sb mine. Whole genome sequencing revealed the presence of multiple sulfur-oxidizing genes, antimony (Sb) metabolism genes and carbon fixation genes in AS-1's genome. We therefore hypothesized that under oxic conditions, AS-1 could mediate the oxidation of sulfide and Sb(III) in stibnite (SbS) and lead to the release of Sb. Indeed, strain AS-1 was discovered as an autotrophic Sb(III)-oxidizer. Antimony mobilization studies conducted with strain AS-1 showed significantly enhanced mobilization of Sb, and complete oxidation of released Sb and sulfur to Sb(V) and sulfate. In addition, AS-1 induced a faster release of Sb under heterotrophic condition, and new acicular minerals might form. These findings support the hypothesis that microorganisms play an important role in the mobilization and transformation of Sb in XKS mine area and may contribute to our further understanding of the Sb biogeochemical redox cycle in natural environment.
Topics: Antimony; Minerals; Oxidation-Reduction; Soil
PubMed: 34949357
DOI: 10.1016/j.jes.2021.03.042 -
Environmental Research Jul 2017Antimony is used as a flame-retardant in textiles and plastics, in semiconductors, pewter, and as pigments in paints, lacquers, glass and pottery. Subacute or chronic...
BACKGROUND
Antimony is used as a flame-retardant in textiles and plastics, in semiconductors, pewter, and as pigments in paints, lacquers, glass and pottery. Subacute or chronic antimony poisoning has been reported to cause sleeplessness. The prevalence of short sleep duration (<7h/night) has been reported to be 37.1% in the general US population, and obstructive sleep apnea (OSA) affects 12-28 million US adults. Insufficient sleep and OSA have been linked to the development of several chronic conditions including diabetes, cardiovascular disease, obesity and depression, conditions that pose serious public health threats.
OBJECTIVE
To investigate whether there is an association between antimony exposure and sleep-related disorders in the US adult population using the National Health and Nutrition Examination Survey (NHANES) 2005-2008.
METHODS
We performed multivariate logistic regression to analyze the association of urinary antimony with several sleep disorders, including insufficient sleep and OSA, in adult (ages 20 years and older) participants of NHANES 2005-2008 (n=2654).
RESULT
We found that participants with higher urinary antimony levels had higher odds to experience insufficient sleep (≤6h/night) (OR 1.73; 95%CI; 1.04, 2.91) as well as higher odds to have increased sleep onset latency (>30min/night). Furthermore, we found that higher urinary antimony levels in participants were associated with OSA (OR 1.57; 95%CI; 1.05, 2.34), sleep problems, and day-time sleepiness.
CONCLUSION
In this study, we found that urinary antimony was associated with higher odds to have insufficient sleep and OSA. Because of the public health implications of sleep disorders, further studies, especially a prospective cohort study, are warranted to evaluate the association between antimony exposure and sleep-related disorders.
Topics: Adult; Aged; Aged, 80 and over; Antimony; Environmental Pollutants; Female; Humans; Male; Middle Aged; Nutrition Surveys; Prevalence; Sleep Wake Disorders; United States; Young Adult
PubMed: 28363141
DOI: 10.1016/j.envres.2017.03.036 -
Parasitology Research Aug 2021Visceral leishmaniasis is a severe disease caused by protozoan parasites that include Leishmania (L.) infantum. The disease is established when parasites subvert the...
Visceral leishmaniasis is a severe disease caused by protozoan parasites that include Leishmania (L.) infantum. The disease is established when parasites subvert the immune response of the host. Notably, chemotherapy-based use of antimonial compounds can partially alleviate disease burden. Unfortunately, the resistance to drug treatments is increasing in areas endemic to the disease. In this report, we investigated immune responses within macrophages infected with antimony-resistant L. infantum isolates from patients with a relapse in the disease. Results revealed that antimony-resistant parasites persist in the first 24 h of infection. Activation of macrophage or blocking of thiol production during infection shows enhanced clearance of parasites, which is coordinately associated with increased production of pro-inflammatory cytokines. Taken together, these results suggest that the mechanism of antimony resistance in L. infantum isolates may be related to a decrease in macrophage microbicidal functions.
Topics: Antimony; Drug Resistance; Humans; Leishmania infantum; Leishmaniasis; Macrophages; Meglumine Antimoniate
PubMed: 34272999
DOI: 10.1007/s00436-021-07231-7 -
The Science of the Total Environment May 2019Ferric oxyhydroxides are natural scavengers of antimony, thus, they contribute significantly to antimony immobilization in soils and sediments. Recent studies, however,...
Ferric oxyhydroxides are natural scavengers of antimony, thus, they contribute significantly to antimony immobilization in soils and sediments. Recent studies, however, usually omit microbial influence on geochemically stable antimony-ferric oxyhydroxide association. Therefore, we have evaluated fungal contribution to antimony mobility during static cultivation of common soil fungus Aspergillus niger in presence of ferric oxyhydroxides. Our results indicate distinguished effect of fungus on antimony distribution at two different antimony concentrations that were used for antimony pre-adsorbtion onto ferric oxyhydroxides prior to the inoculation. Approximately 36% of antimony was bioextracted by fungus from antimony bearing ferric oxyhydroxide after 14-day cultivation when the 8.9 mg·L antimony concentration was used for pre-adsorption. However, no statistically significant change of antimony content in ferric oxyhydroxides was observed after cultivation when initial 48 mg·L antimony concentration was used for pre-adsorption. As Mössbauer spectroscopy and XRD analysis indicated, nanosized akageneite, goethite, and lepidocrocite enhanced their crystallinity during cultivation, while hematite was identified only after the cultivation. Nevertheless, presence of ferric oxyhydroxides at both initial concentrations enabled transformation of antimony into volatile derivatives, and almost 9.5% of antimony was biovolatilized after cultivation. These results contribute significantly to environmental geochemistry of antimony-ferric oxyhydroxides association and highlight the importance of microbial activity in relation to ferric component of natural geochemical barriers.
Topics: Adsorption; Antimony; Biotransformation; Ferric Compounds; Fungi; Soil Pollutants
PubMed: 30763848
DOI: 10.1016/j.scitotenv.2019.02.033 -
Metal Ions in Life Sciences 2010The presence of methylated antimony species has been reported in surface waters, sediments, soils, and biota, mainly detected using hydride generation techniques.... (Review)
Review
The presence of methylated antimony species has been reported in surface waters, sediments, soils, and biota, mainly detected using hydride generation techniques. Compared to other elements, relatively few studies have been published. Monomethyl-, dimethyl-, and trimethylantimony species have been found, always at very low concentrations. It is important to point out that (i) it has been proved that the identity of some of the published species might be uncertain due to possible artefacts during the analytical process; (ii) existing analytical methods do not reveal the oxidation state of the antimony in the detected species. Volatile methylated species have also been detected in landfill and sewage fermentation gases. Laboratory culture experiments have indicated that biomethylation can result from bacterial, yeast, and fungal activity, in both aerobic and anaerobic conditions. Antimony is methylated much less rapidly and less extensively than arsenic and it has been suggested that antimony biomethylation could be a fortuitous rather than a detoxification process.
Topics: Animals; Antimony; Biota; Environmental Microbiology; Gas Chromatography-Mass Spectrometry; Methylation; Organometallic Compounds; Sewage; Water Pollutants, Chemical
PubMed: 20877810
DOI: 10.1039/BK9781847551771-00267 -
IARC Monographs on the Evaluation of... 1989
Review
Topics: Animals; Antimony; Carcinogens; Chemical Phenomena; Chemistry; Humans; Risk Factors; Sulfides
PubMed: 2699902
DOI: No ID Found -
Regulatory Toxicology and Pharmacology... Feb 2021Polyester fibres are usually contaminated by antimony because of its use as a catalyst in the production of polyethylene terephthalate and as a flame retardant synergist...
Polyester fibres are usually contaminated by antimony because of its use as a catalyst in the production of polyethylene terephthalate and as a flame retardant synergist in a variety of new and recycled polymers. The present study determined the release of antimony (at total concentrations ranging from about 125 to 470 μg g) from polyester textile samples designed to be in contact with human skin using standard artificial sweat solutions (ISO 105-E04 and EN 1811). The study also examined the role of different experimental parameters on the release of the metalloid. Overall, and using the default parameters, between about 0.05 and 2% of total antimony (or 0.1-1 μg g) was mobilized into artificial sweat. A reduction in time (from 24 to 12 h) and temperature (from 37 to 20 or 4 °C) and an increase in pH (from 5.5 to 7) resulted in a decline in antimony mobilization from textiles, while altering textile mass to solution volume and the presence of lactate had little impact on the results. Removal of a filtration step increased antimony mobilization but this was attributed to artefacts associated with release from microfibres during extract storage and analysis. In general, antimony mobilization was sufficiently repeatable using either EN 1811 or ISO 105-E04 but the latter is recommended for an assessment of antimony mobilization and potential exposure because its pH is closer to that of human sweat. Since the first fraction of either extractions mobilized the greatest quantity of antimony, exposure can be minimized by washing articles before use.
Topics: Antimony; Flame Retardants; Polyesters; Reference Standards; Sweat; Textiles
PubMed: 33221423
DOI: 10.1016/j.yrtph.2020.104824 -
The American Journal of Tropical... May 1995Chemical methods specific for the determination of the levels of trivalent antimony (Sb+3) and pentavalent antimony (Sb+5) were used to investigate proprietary formulas...
Chemical methods specific for the determination of the levels of trivalent antimony (Sb+3) and pentavalent antimony (Sb+5) were used to investigate proprietary formulas used to treat leishmaniasis. Trivalent antimony was determined by differential pulse polarography, whereas Sb+5 was determined by iodine titration. Proprietary formulas based on N-meglumine antimoniate (Glucantime) were analyzed in detail. The results showed Sb+3 in all ampules of Glucantime. In formulations said to contain either 85 or 100 mg of Sb+5/ml, we found both forms of antimony. The amount of Sb+3 ranged from 10.5 to 15.8% (10.06-18.96 mg of Sb/ml). These findings raise issues on product stability and standardization and may help to clarify resistance to antimonial drugs and the reducing effect of tissue on Sb+5.
Topics: Antimony; Antimony Sodium Gluconate; Antiprotozoal Agents; Drug Stability; Meglumine; Meglumine Antimoniate; Organometallic Compounds; Oxidation-Reduction
PubMed: 7771610
DOI: 10.4269/ajtmh.1995.52.435