New Evidences of Key Factors Involved in “Silent Stones” Etiopathogenesis and Trace Elements: Microscopic, Spectroscopic, and Biochemical Approach

Abstract

The knowledge of the key factors involved in etiopathogenesis of the gallstone disease requires chemical, structural, and elemental composition analysis. The application of different complementary analytical techniques, both microscopic and spectroscopic, are aimed to provide a more comprehensive determination of the gallbladder calculi ultrastructure and trace element identification. High sensitivity techniques such as electron microscopy (SEM), Fourier transform infrared (FTIR), electron paramagnetic resonance (EPR) spectroscopy, and X-ray diffraction (XRD) along with biochemical analysis are used in a new attempt to investigate various factors which play a regulatory role in the pathogenesis of gallstones. The microstructure of different types of gallbladder stones has specific characteristics which are related to the elemental composition. The binding of metal ions with bile salts and bilirubin plays important roles in gallstone formation as revealed by FTIR spectrum of calcium bilirubinate complex in pigment gallstones. The EPR results demonstrated the generation of bilirubin free radicals and variation of its electronic structure and conjugation system in the skeleton of bilirubin molecule during complex formation. EPR spectra of pigment gallstones demonstrate the coexistence of four paramagnetic centers including stable bilirubin free radical, Mn2+, Cu2+, and Fe3+ with distinct magnetic parameters and well-resolved hyperfine structure in the case of Mn2+ ions. The result confirms a macromolecular network structure with proteins and the formation of bilirubin-coordinated polymer. Bilirubin and bilirubinate free radical complexes may play an important role in pigment gallstone formation.

A Bezoar Composed of Bilirubin Calcium, Calcium Carbonate, and Fatty Acid Calcium

“…Gallstones are classified into cholesterol stones, brown stones, black stones, and mixed stones [7–9]. The white stones are composed of ≥50% of cholesterol, whereas black and brown stones, which contain different proportions of cholesterol and bilirubin, are composed of ≤30% of cholesterol by weight [10].…”

“…The white stones are composed of ≥50% of cholesterol, whereas black and brown stones, which contain different proportions of cholesterol and bilirubin, are composed of ≤30% of cholesterol by weight [10]. Gallstone components other than cholesterol and bilirubin include calcium carbonate, phosphate salts, phospholipids, fatty salts, polysaccharide, and proteins, along with minor elements such as potassium, calcium, manganese, iron, copper, zinc, chlorine, and sulfur [7, 11–14]. In the present patient, infrared spectroscopy revealed that the bezoar was composed of fatty acid calcium, calcium carbonate, and bilirubin calcium.…”

Morphological and elemental mapping of gallstones using synchrotron microtomography and synchrotron X‐ray fluorescence spectroscopy

“…Evidence from literature abounds with information on the pronucleating factors in bile, such as N‐aminopeptidase, fibronectin, immunoglobulins, acidic glycoproteins, mucin, and lipoproteins . Cavalu et al , using a deconvolution procedure, report that the random coils may represent the dominant secondary structure of proteins that may be involved in GS pathogenesis. The XRD pattern in their study confirmed that mixed and pigment GS had calcium bilirubinate complex formation, together with anhydrous and monohydrate forms of cholesterol.…”

Nano-Scale Modifications of Amniotic Membrane Induced by UV and Antibiotic Treatment: Histological, AFM and FTIR Spectroscopy Evidence

“…The amide I spectral band was baseline-corrected, and the area was normalized and deconvoluted in the interval 1600-1700 cm −1 . The percentage of protein secondary structures (α-helix, β-sheets, turns, unordered and side chains) was calculated based on the area under each peak, and the assignments of the components were conducted according to the literature [19][20][21]. Results were represented as mean ± standard deviation (SD) for three independent experiments.…”

“…In the higher-wavenumber region, the interval 3190-3300 cm −1 is assigned to O-H and C-H bending vibrations, while the band at 2950 cm −1 can be assigned to the asymmetric stretching mode of the CH3 group. The O-H stretching region can be correlated to the hydrogen bond network around the protein, assuming that a certain hydration level still exists after the drying procedure [19,24]. However, water deprivation and restitution might have some consequences on the macromolecular structure.…”