A Novel Oxidovanadium (IV)-Orotate Complex as an Alternative Antidiabetic Agent: Synthesis, Characterization, and Biological Assessments

The antihyperglycemic and hypolipidemic activities of a sulfur-oxidovanadium(IV) complex

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 ([V^IVO(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 (V^IVOSO₄). The effects of treatment with ([V^IVO(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 [V^IVO(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 [V^IVO(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 [V^IVO(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 [V^IVO(octd)], vanadium species resulting from redox processes, the hydrolysis of [V^IVO(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.

In vitro and in vivo evaluations on nanoparticle and phospholipid hybrid nanoparticles with absorption enhancers for oral insulin delivery

Oral delivery of peptide and proteins is challenging due to their poor physical and chemical stability which usually results in inadequate therapeutic efficacy. Nanoparticles encapsulating insulin was developed by the ionic gelation technique using sulfobutyl ether-β-cyclodextrin as an anionic linker. Phospholipid hybrid nanoparticles were formulated by utilizing ionic gelation and thin-film hydration methods using D-α-Tocopheryl polyethylene glycol 1000 succinate, sodium deoxycholate separately and in combination to take the advantage of liposomes and nanoparticles also various absorption enhancement mechanisms. All formulations were characterized and tested for in vitro gastrointestinal stability, in vitro drug release, and cytotoxicity. On the other hand, in vivo effects of developed formulations on reducing blood glucose levels were monitored for 8 hours. Phospholipid hybrid nanoparticles including D-α-Tocopheryl polyethylene glycol 1000 succinate and sodium deoxycholate in combination with 548.7 nm particle size, 0.332 polydispersity index, 22.0 mV zeta potential, and 61.9% encapsulation efficiency, exhibited desired gastrointestinal stability and insulin release in vitro. In addition, the formulation proved its safety with cytotoxicity studies on L929 cells. The subjected phospholipid hybrid nanoparticle formulation was found to be the most effective formulation by reducing and maintaining blood glucose levels with avoiding fluctuations.

Synthesis, Characterization, and Anti-diabetic Activity of Some Novel Vanadium-Folate-Amino Acid Materials

A new six intraperitoneal injections insulin-mimetic vanadyl(IV) compounds [(VO)(FA)(AA_n)] (where n = 1–6: AA₁ = isoleucine, AA₂ = threonine, AA₃ = proline, AA₄ = phenylalanine, AA₅ = lysine, and AA₆ = glutamine) were synthesized by the chemical reactions between folic acid (FA), VOSO₄, and amino acids (AA_n) with equal molar ratio 1:1:1 in neutralized media. These complexes were characterized by elemental analysis and estimation of vanadyl(IV) metal ions. The thermal stability behavior of these complexes was studied by TG-DTG-DTA analyses. The structures of these complexes were elucidated by spectroscopic methods like infrared, electron spin resonance (ESR), and solid reflectance spectroscopes. The powder X-ray diffraction (XRD) study suggested the crystalline nature of the complexes. Magnetic moments and electronic spectra revealed the square-pyramid geometrical structure of the complexes. The conductivity results refereed that all synthesized vanadyl(IV) complexes were of a non-electrolyte behavior. The infrared spectra assignments of these complexes revealed that the FAH₂ and AA_n chelates act as a bidentate ligation. The chelation towards vanadyl (IV) ions existed via deprotonation of one of the carboxylic groups of FAH₂ drug ligand, and so amino acids act as bidentate ligands via N-amino and O-carboxylate groups. Both scanning and transmission electron microscope (SEM and TEM) techniques were used to investigate the surface morphology. The main task of this research is the aim of designing a new insulin alternative antidiabetic drug agent. The antidiabetic efficiency of these complexes was evaluated in streptozotocin-induced diabetic male albino rats. Liver and kidney functions, insulin and blood glucose levels, lipid profile, and superoxide dismutase antioxidant (SOD) are verified identifiers for the efficiency of VO(IV)/FA/AA_n system compounds as antidiabetic drug agents.

Synthesis and Biological Evaluations of a Novel Oxidovanadium(IV) Adenosine Monophosphate Complex as Anti-Diabetic Agent

In the present study, a novel [(AMP)(VO)(H2O)2] complex was formed through chemical reactions between oxidovanadium(IV)sulfate and adenosine monophosphate. This complex was characterized using various analyses, including microanalytical, molar conductivity, spectroscopic (solid reflectance and FTIR), magnetic susceptibility, thermogravimetric (TGA), X-ray powder diffraction (XRD), and scanning (SEM) and transmission (TEM) electron microscopy. The in vivo antidiabetic activity of the oxidovanadium(IV) complex was determined using streptozotocin-induced rats. The results suggested that the synthesized complex can be used as an antidiabetic agent based on the observed biochemical effects.