Methodologies of Tissue Preservation and Analysis of the Glycogen Content of the Broiler Chick Liver,

Abstract

The current study was performed to develop convenient, rapid, reliable, and pragmatic methodologies by which to harvest and preserve liver tissue glycogen and to analyze its levels within reasonable limits of quantification and with extended chromophore stability. Absorbance values decreased by 2 h and again by 24 h after preparation of the iodine-potassium iodide chromophore, whereas absorbance values of the phenol-sulfuric acid chromophore remained constant over the same time period. These absorbance trends for each chromophore followed full color development within 5 min after combining the analyte with the respective chromophore reagent. Use of the phenol-sulfuric acid reagent allowed for a 10-fold reduction in assay limits of detection and quantification when compared with the iodine-potassium iodide reagent. Furthermore, glycogen concentration-absorbance relationships were affected by the source (i.e., rabbit liver vs. bovine liver) of glycogen standards when the iodine-potassium iodide chromophore was used, but the source of the standards had no influence when the phenol-sulfuric acid chromophore was used. The indifference of the phenol-sulfuric acid method to the glycogen source, as exhibited by similar linear regressions of absorbance, may be attributed to actual determination of glucose subunit concentrations after complete glycogen hydrolysis by sulfuric acid. This is in contrast to the actual measurement of whole glycogen, which may exhibit source- or time-related molecular structural differences. The iodine-potassium iodide methodology is a test of whole glycogen concentrations; therefore, it may be influenced by glycogen structural differences. Liver tissue sample weight (between 0.16 and 0.36 g) and processing, which included mincing, immediate freezing, or refrigeration in 10% perchloric acid for 1 wk prior to tissue grinding, had no effect on glycogen concentrations that were analyzed by using the phenol-sulfuric acid reagent. These results indicate that small field samples may be minced, immediately placed in 10% perchloric acid without freezing, and then processed in the laboratory up to 1 wk later when using a phenol-sulfuric acid reagent, as described in this study, to determine the glycogen concentration in broiler chick livers accurately.

Betaine Supplementation in Maternal Diet Modulates the Epigenetic Regulation of Hepatic Gluconeogenic Genes in Neonatal Piglets

“…The hepatic glycogen content was determined as previously described [22]. The results are expressed as mg glycogen/g liver (wet weight).…”

Physiological relationships of the early posthatch performance of broilers to their embryo and eggshell characteristics

“…Upon necropsy and organ collection from each IC, a 0.25-g sample was immediately taken from each liver (left lobe) and pipping muscle and was stored and preserved in a plastic vial containing 10% perchloric acid (Bennett et al, 2007). Subsequently, glucose, glycogen, protein, and fat concentrations were determined in each of the individual liver and pipping muscle samples harvested.…”

“…Subsequently, glucose, glycogen, protein, and fat concentrations were determined in each of the individual liver and pipping muscle samples harvested. Tissue glucose and glycogen concentrations were determined using the phenol-sulfuric acid method as described by Bennett et al (2007). Colorimetric protein estimation was accomplished according to Lowry et al (1951), and colorimetric fat was determined using the methodology of Van Handel (1985).…”

Anti-Glycemic and Anti-Hepatotoxic Effects of Mangosteen Vinegar Rind from Garcinia mangostana Against HFD/STZ-Induced Type II Diabetes in Mice

“…The supernatant was carefully discarded and the glycogen was resolved in 1 mL of distilled water. The total glycogen content was measured following the phenolsulfuric acid method using a microplate reader (Multiskan GO, Thermo Fisher Scientifi c, Waltham, MA, USA) [Bennett et al, 2007;Masuko et al, 2005].…”