Decreased Sulfate Content and Zeta Potential Distinguish Glycosaminoglycans of the Extracellular Matrix of Osteoarthritis Cartilage

We aimed to determine the characteristics that distinguish glycosaminoglycans (GAGs) from osteoarthritis (OA) and normal cartilage and from men and women. Cartilage samples from 30 patients subjected to total joint arthroplasty secondary to OA or fracture (control) were evaluated, and the GAG content (μg/mg dry cartilage) after proteolysis was determined by densitometry, using agarose-gel electrophoresis. Relative percentages of carbon (C), nitrogen (N), and sulfur (S) in GAGs were determined by elemental microanalysis, as well as the zeta potential. Seventeen samples (56.6%) were from patients >70 years old, with 20 (66.6%) from women, and most [20 (66.6%)] were from the hip. The GAG content was similar regardless of patients being >/≤ 70 years old with 96.5 ± 63.5 and 78.5 ± 38.5 μg/mg (P = 0.1917), respectively. GAG content was higher in women as compared to men, with 89.5 ± 34.3 and 51.8 ± 13.3 μg/mg, respectively (P = 0.0022), as well as in OA than fracture samples, with 98.4 ± 63.5 and 63.6 ± 19.6 μg/mg, respectively (P = 0.0355). The GAG extracted from the cartilage of patients >70 years old had increase in N, and there were no gender differences regarding GAG elemental analysis. GAG from OA had a highly significant (P = 0.0005) decrease in S% (1.79% ± 0.25%), as compared to fracture samples (2.3% ± 0.19%), with an associated and significant (P = 0.0001) reduction of the zeta potential in the OA group. This is the first report of a reduced S content in GAG from OA patients, which is associated with a reduced zeta potential.

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Convenient Agarose Preparation with Hydrogen Peroxide and Desulfation Process Analysis

Marine Drugs ◽

10.3390/md19060297 ◽

2021 ◽

Vol 19 (6) ◽

pp. 297

Author(s):

Cong Zhang ◽

Ding An ◽

Qiong Xiao ◽

Fu-Quan Chen ◽

Yong-Hui Zhang ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Gel Electrophoresis ◽

Process Analysis ◽

Gel Strength ◽

Agarose Gel ◽

Agarose Gel Electrophoresis ◽

Metal Sulfate ◽

Sulfate Content ◽

Sulfate Ions ◽

Electrical Neutrality

Agarose is a natural seaweed polysaccharide and widely used in the medicine, food, and biological fields because of its high gel strength, non-toxicity, and electrical neutrality. The sulfate group is one of the main charged groups that affect the performance of agarose. In the present study, a simple, eco-friendly, and efficient method was explored for agarose preparation. After desulfation with hydrogen peroxide (H2O2), the sulfate content of agar reached 0.21%. Together with gel strength, electroendosmosis, gelling and melting temperature, the indicators of desulfated agar met the standards of commercially available agarose. Notably, the desulfated agar can be used as an agarose gel electrophoresis medium to separate DNA molecules, and the separation effect is as good as that of commercially available agarose. Further, the H2O2 desulfation process was analyzed. The addition of a hydroxyl radical (HO•) scavenger remarkably decreased the H2O2 desulfation rate, indicating that HO• has a certain role in agar desulfation. Sulfate content detection indicated that sulfur was removed from agar molecules in the form of sulfate ions (SO42−) and metal sulfate. The band absence at 850 cm−1 indicated that the sulfate groups at C-4 of D-galactose in sulfated galactan were eliminated.

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Interaction of Cationic Carbosilane Dendrimers and Their siRNA Complexes with MCF-7 Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22137097 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7097

Author(s):

Kamila Białkowska ◽

Katarzyna Miłowska ◽

Sylwia Michlewska ◽

Paulina Sokołowska ◽

Piotr Komorowski ◽

...

Keyword(s):

Gene Therapy ◽

Zeta Potential ◽

Gel Electrophoresis ◽

Positive Charge ◽

Agarose Gel ◽

Agarose Gel Electrophoresis ◽

Carbosilane Dendrimers ◽

Xtt Assay ◽

Promising Solution ◽

Mcf 7

The application of siRNA in gene therapy is mainly limited because of the problems with its transport into cells. Utilization of cationic dendrimers as siRNA carriers seems to be a promising solution in overcoming these issues, due to their positive charge and ability to penetrate cell membranes. The following two types of carbosilane dendrimers were examined: CBD-1 and CBD-2. Dendrimers were complexed with pro-apoptotic siRNA (Mcl-1 and Bcl-2) and the complexes were characterized by measuring their zeta potential, circular dichroism and fluorescence of ethidium bromide associated with dendrimers. CBD-2/siRNA complexes were also examined by agarose gel electrophoresis. Both dendrimers form complexes with siRNA. Moreover, the cellular uptake and influence on the cell viability of the dendrimers and dendriplexes were evaluated using microscopic methods and XTT assay on MCF-7 cells. Microscopy showed that both dendrimers can transport siRNA into cells; however, a cytotoxicity assay showed differences in the toxicity of these dendrimers.

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Luminography – an Alternative Assay for Detection of von Willebrand Factor Multimers

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647016 ◽

1988 ◽

Vol 60 (02) ◽

pp. 133-136 ◽

Cited By ~ 50

Author(s):

R Schneppenheim ◽

H Plendl ◽

U Budde

Keyword(s):

Von Willebrand Factor ◽

Gel Electrophoresis ◽

Detection Methods ◽

Agarose Gel ◽

Agarose Gel Electrophoresis ◽

Luminescence Assay ◽

Von Willebrand ◽

Willebrand Factor

SummaryA luminescence assay was adapted for detection of von Willebrand factor multimers subsequent to SDS-agarose gel electrophoresis and electroblotting onto nitrocellulose. The method is as fast as chromogenic detection methods and appears to be as sensitive as autoradiography without the disadvantages of the latter.

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