The insulin enhancing activity, histological analysis and, testicular degeneration by a VIVO-complex containing the 2,2′-(ethane-1,2-diylbis(azanediyl))diethanolate ligand, VOIV(C6H14N2O2-κ2N,κ2O), ...abbreviated VIVO(BHED), were investigated in diabetic male Wistar rats. The complex was administered by oral gavage of freshly prepared solutions of vanadium complex. Biological studies demonstrated that the vanadium complex normalized the elevated glucose levels in male Wistar rats with streptozotocin-induced diabetes and these compounds also avoided common responses in diabetic animals such as weight loss and reduction in the size of the epididymis, prostate, testis and seminal gland. The 51V NMR and EPR studies showed the formation of VIVO(BHED) and the oxidation product VVO2BHED− with two possible decomposition pathways. In summary, these studies demonstrate that the VIVO(BHED) complex or its decomposition products show similar effects as insulin in decreasing elevated blood glucose levels.
The oxidovanadium(IV)-diamine complex was synthesized and characterized. The insulin enhancing activity, histological analysis and testicular degeneration were performed in diabetic male Wistar rats. The treatment with the complex avoids development of commonly responses in diabetic individuals, such as weight loss and reduction in the size of the epididymis, prostate, testis. Furthermore, glucose values after seven weeks of VIV-complex treatment were equivalent to those found with insulin treatment, suggesting that the complex can be used as oral hypoglycemic agent. Display omitted
•The synthesis, characterization and biological activity of a oxovanadium(IV) complex•Glucose values of vanadium(IV) treatment were normalized in Wistar diabetic-STZ rats.•The oxovanadium(IV) complex showed a significantly smaller reduction of the epididymis, prostate and testis.
Vanadium compounds are known to exert insulin-enhancing activity, normalize elevated blood glucose levels in diabetic subjects, and show significant activity in models of insulin resistance (IR). ...Faced with insulin resistance, the present work investigates the antidiabetic performance of a known oxidovanadium(IV)-based coordination compound—VIVO(octd)—and effects associated with glucocorticoid-induced insulin resistance in mice. The effects of VIVO(octd) were evaluated in a female Swiss mice model of insulin resistance induced by seven days of dexamethasone treatment in comparison with groups receiving metformin treatment. Biological assays such as hematological, TyG index, hepatic lipids, glycogen, oxidative stress in the liver, and oral glucose tolerance tests were evaluated. VIVO(octd) was characterized with 51V NMR, infrared spectroscopy (FTIR), electron paramagnetic resonance (EPR), electronic absorption spectroscopy, and mass spectrometry (ESI–FT–MS). The VIVO(octd) oral treatment (50 mg/kg) had an antioxidant effect, reducing 50% of fast blood glucose (p < 0.05) and 25% of the TyG index, which is used to estimate insulin resistance (p < 0.05), compared with the non-treated group. The oxidovanadium–sulfur compound is a promising antihyperglycemic therapeutic, including in cases aggravated by insulin resistance induced by glucocorticoid treatment.
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•Fluorimetric determination of formaldehyde using a nickel complex immobilized as a solid phase.•Formaldehyde analysis was able to be conducted in 05 min with a relative standard ...deviation estimated at 1.10 %.•Nickel waste was completely recovered implementing the principles of greener and sustainable chemistry.
Formaldehyde (FA) is a highly toxic substance present in many matrices, including freshwater as well as found in natural mechanisms such as rainfall and combustion of organic matter. Consumption of water contaminated with high levels of FA can cause severe short-term or long-term health problems. Due to these health risks, procedures are necessary to determine and quantify FA in aqua sources This paper reports on a study of fluorimetric determination of FA using a nickel(2 + )-diketonate coordination compound immobilized as a solid precursor. The compound was characterized by electronic absorption, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetry (TG), optical microscopy (OM), and scanner electron microscopy (SEM). The methodology was based on the reaction of the synthesized compound with an ammoniacal buffer generating a selective reagent for formaldehyde: fluoral-P. The product of the reaction generates 3,5-diacetyl-1,4-dihydrolutidine (DDL), which is responsible for the fluorescence of the system. Several parameters such as temperature, duration of heating time, and dilution effect with the best effects were studied to carry out FA determination. Under the optimum experimental conditions, a linear response ranging from 1.0 to 10.0 mg/L FA (R = 0.997 and n = 10), and a detection (3σ criterion) and quantification (10 σ criterion) limit estimated at 0.129 and 0.389 mg/L, respectively were achieved. The FA analysis was able to be conducted in 05 min with a relative standard deviation estimated at 1.10 %.
This study describes the synthesis, characterization, and biological activity of a new class of antidiabetic oxidovanadium(IV)-complexes with S2O2 coordination mode. The target complex ...3,6-dithio-1,8-octanediolatooxidovanadium(IV), abbreviated as (VIVO(octd)), where octd = 3,6-dithio-1,8-octanediol, is formed from the reaction between the 3,6-dithio-1,8-octanediol and vanadyl sulfate (VIVOSO4). The effects of treatment with (VIVO(octd) on blood glucose, lipidic profile, body weight, food intake, water intake, urinary volume, glycogen levels, and biomarkers for liver toxicity were investigated using a streptozotocin (STZ)-induced diabetic Wistar rats model. The results have shown that the VIVO(octd) complex caused a significant decrease in blood glucose (247.6 ± 19.3 mg/dL vs 430.1 ± 37.6 mg/dL diabetic group, p < 0.05), triglycerides (TG, 50%) and very low-density cholesterol (VLDL-C, 50%) levels in STZ-diabetic rats after 3 weeks of treatment. The VIVO(octd) has shown antihyperglycemic activity in diabetic rats as well as a reduction in elevated lipid levels. Time-dependent studies using EPR and 51V NMR spectroscopy of VIVO(octd) were done in aqueous solutions to determine the complex stability and species present in the oral gavage solution used for complex administration. The spectroscopic studies have shown that the antidiabetic/hypolipidemic activity could be attributed to VIVO(octd), vanadium species resulting from redox processes, the hydrolysis of VIVO(octd) and its decomposition products, or some combination of these factors. In summary, the oxidovanadium(IV) complex containing the S2O2 donor ligand has desirable antidiabetic properties eliminating the symptoms of Diabetes mellitus and its comorbidities.
The VIVO(octd), where octd = 3,6- dithio-1,8-octanediol, complex showed antidiabetic effects, lowering the levels of blood-glucose, triglycerides and low density-cholesterol in Streptozotocin (STZ)-induced diabetes Wistar rats. Display omitted
•Synthesis of 3,6-dithio-1,8-octanediolatooxidovanadium(IV) with a S2O2 coordination mode.•51V NMR and EPR spectroscopic studies determine speciation in the administration solution.•Evaluation of antidiabetic properties of the complex in Streptozotocin (STZ)-induced diabetes Wistar rats.•The complex lowered the blood glucose from 430.1 ± 37.6 mg/dL to 247.6 mg/dL ± 19.3 mg/dL (p < 0.05).•The complex reduced triglycerides and low-density cholesterol levels.
The vanadium(V) complexes have been investigated as potential anticancer agents which makes it essential to evaluate their toxicity for safe use in the clinic. The large-scale synthesis and the acute ...oral toxicity in mice of the oxidovanadium(V) Schiff base catecholate complex, abbreviated as VO(HSHED)dtb containing a redox-active ligand with tridentate Schiff base (HSHED = N-(salicylideneaminato)-N’-(2-hydroxyethyl)-1,2-ethylenediamine) and dtb = 3,5-di-(t-butyl)catechol ligands were carried out. The body weight, food consumption, water intake as well biomarkers of liver and kidney toxicity of the VO(HSHED)dtb were compared to the precursors, sodium orthovanadate, and free ligand. The 10-fold scale-up synthesis of the oxidovanadium(V) complex resulting in the preparation of material in improved yield leading to 2–3 g (79%) material suitable for investigating the toxicity of vanadium complex. No evidence of toxicity was observed in animals when acutely exposed to a single dose of 300 mg/kg for 14 days. The toxicological results obtained with biochemical and hematological analyses did not show significant changes in kidney and liver parameters when compared with reference values. The low oral acute toxicity of the VO(HSHED)dtb is attributed to redox chemistry taking place under biological conditions combined with the hydrolytic stability of the oxidovanadium(V) complex. These results document the design of oxidovanadium(V) complexes that have low toxicity but still are antioxidant and anticancer agents.
•Polysiloxane crown ether column for the analysis of trace perchlorate in vegetables.•Multi-commutated flow-analysis concept with potentiometric detection.•Nanomolar perchlorate ...determination.•Perchlorate as an environmental contaminant effectively monitored.
In this work, an expeditious method based on the multi-commutated flow-analysis concept with potentiometric detection is proposed to perform determinations of the emergent contaminant perchlorate in vegetable matrices down to nanomolar concentration. To accomplish the task, a tubular shaped potentiometric sensor selective to perchlorate ion was constructed with a PVC membrane containing 12mmol/kg of the polyamine bisnaphthalimidopropyl-4,4′-diaminodiphenylmethane and 2-nitrophenyl phenyl ether 68% (w/w) as plasticizer casted on a conductive epoxy resin. Under optimal flow conditions, the sensor responded linearly in the concentration range of 6.3×10−7–1.0×10−3mol/L perchlorate. In order to extend the determinations to lower concentrations (4.6(±1.3)×10−10mol/L perchlorate), a column packed with 70mg of sodium 2,5,8,11,14-pentaoxa-1-silacyclotetradecane-polymer was coupled to the flow-system thus enabling prior pre-concentration of the perchlorate. The proposed procedure provides a simpler alternative for the determination of perchlorate in foods, nowadays only allowed by sophisticated and expensive equipment and laborious methods.
Polyoxovanadates (POV) are a subgroup of polyoxometalates (POM), which are nanosized clusters with reported biological activities. This manuscript describes the first toxicity evaluation of a ...mixed-valence polyoxovanadate, pentadecavanadate, (Me4N)6V15O36Cl, abbreviated as V15. Cytotoxicity experiments using peripheral blood mononuclear cells (PBMC), larvae of Artemia salina Leach, and in vivo oral acute and repeated 28-day doses in mice was carried out. The LC50 values in PBMC cells and A. salina were 17.5 ± 5.8 μmol L−1, and 17.9 µg L−1, respectively, which indicates high cytotoxic activity. The toxicity in mice was not observed upon acute exposure in a single dose, however, the V15 repeated 28-day oral administration demonstrated high toxicity using 25 mg/kg, 50 mg/kg and, 300 mg/kg doses. The biochemical and hematological analyses during the 28-day administration of V15 showed significant alteration of the metabolic parameters related to the kidney and liver, suggesting moderate toxicity. The V15 toxicity was attributed to the oxidative stress and lipid peroxidation, once thiobarbituric acid (TBAR) levels significantly increased in both males and females treated with high doses of the POV and also in males treated with a lower dose of the POV. This is the first study reporting a treatment-related mortality in animals acutely administrated with a mixed-valence POV, contrasting with the well-known, less toxic decavanadate. These results document the toxicity of this mixed-valence POV, which may not be suitable for biomedical applications.
A NEW DINUCLEAR COORDINATION COMPOUND DESIGNED TO HAVE NO OXIDATIVE DAMAGE AND TOXICOLOGICAL EFFECTS. The synthesis, characterization, acute toxicity, antitumor activity, and histopathological ...analysis of a novel dinuclear platinum(2+) complex − Pt(DACH-κ2N)µ-(C4H2O6-κ4O)Pt(DACH-κ2N) − is reported. Through acute toxicity tests, it was possible to place the platinum complexes into categories according to the OECD protocol. The dinuclear complex was classified in category 2 (cisplatin - category 1; and oxaliplatin - category 2). Analyzing the interaction between dsDNA and dinuclear complex was observed an Tm increase, suggesting that the dinuclear complex-dsDNA interact probably through of the interstrand form. Evaluations of tumor masses extracted from mice inoculated with Ehrlich carcinoma demonstrated a percent of tumor inhibition similar for cisplatin and oxaliplatin, but statistically different and superior for the case of the dinuclear complex. Cisplatin and oxaliplatin showed 41.4 and 40.8% inhibition, respectively, while the dinuclear complex presented 66.3%. The histopathological analysis demonstrated that the group treated with cisplatin showed more significant tissue damage, moderate hepatic steatosis, and nephritis. The livers, spleens, and kidneys of the animals treated with the dinuclear complex were within the normality range with no tissue lesions, and absence of metastasis.
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