Effects of Indigo Carmine on Human Chondrocytes In Vitro

Abstract

Joint infections following or accompanying superficious soft tissue infections are severe complication in orthopedic surgery. The use of intra-articular blue staining is a helpful method to visualize a fistula and to differentiate between superficial and intra-articular infections. Regarding this clinical implication data about the effects of indigo carmine, a frequently used blue staining substance, on cartilage is missing. The hypothesis of this study was that indigo carmine damages human chondrocytes in a time and concentration dependent manner. Human chondrocytes were isolated from donors with osteoarthritis who were treated with TKA. Cells were cultivated and treated with different concentrations of indigo carmine for 5 and 10 minutes. Morphologic damage was examined by light microscopy. Toxicity was quantified by counting vital cell number and lactate dehydrogenase (LDH) expression. Analysis by light microscopy showed defected cell structure and loss of cell number after treatment with 100% indigo carmine for 10 minutes. Treatment with 10% and 1% indigo carmine showed no significant cell defects and loss of cells. Counting vital cell number showed loss of vital cells after treatment with 100% and 10% indigo carmine for 10 minutes. LDH expression was significantly increased after treatment with 100% indigo carmine.Toxic effects were shown after treatment with indigo carmine. Therefore, it should be used in 1:100 dilution. This is both, sufficient for visualizing a fistula in a possible clinical application and could be protective for chondrocytes.

Effects of some cosmetic dyes and pigments on the proliferation of human foreskin fibroblasts and cellular oxidative stress; potential cytotoxicity of chlorophyllin and indigo carmine on fibroblasts

“…Although according to some texts, indigo carmine is not toxic, researchers recently have identified some hazardous effects, such as mutagenicity for this dye 33 . Treatment of the isolated human chondrocytes with 100% and 10% of indigo carmine has shown a clear loss of active cells followed by significant LDH expression in the case of using 100% of indigo carmine 34 . Further investigation on indigo toxicity mechanisms revealed that this dye could act on aryl hydrocarbon receptor (AhR), which probably allows inhibition of myofibroblast differentiation and extracellular matrix production, 35 which is in line with our finding on the toxicity of indigo carmine on human fibroblast cells.…”

“…33 Treatment of the isolated human chondrocytes with 100% and 10% of indigo carmine has shown a clear loss of active cells followed by significant LDH expression in the case of using 100% of indigo carmine. 34 Further investigation on indigo toxicity mechanisms revealed that this dye could act on aryl hydrocarbon receptor (AhR), which probably allows inhibition of myofibroblast differentiation and extracellular matrix production, 35 which is in line with our finding on the toxicity of indigo carmine on human fibroblast cells. Some previous reports have indicated a positive effect for chlorophyllin on the viability of the human periodontal ligament cell.…”

Indigo Carmine: Between Necessity and Concern

“…Indigo carmine is used in orthopedics and trauma surgery for staining cystic lesions at the knee and hip level (a 0.8% solution) or in herniated disc surgery (a 10 or 20% solution) [99,105]. It is also used for intradiscal visualization through the preferential staining of the degenerated nucleus pulposus [106].…”

“…Indigo carmine was tested in vitro on cell cultures prepared from bovine coccygeal intervertebral disc tissue, and it was demonstrated that the staining efficacy and cytotoxicity were proportional to dye concentration, but significant toxicity was observed at concentrations higher than 2.5 mg/mL [146]. Furthermore, the effect of indigo carmine was tested in vitro on human chondrocytes, where a significant decrease in the number of viable cells was observed at concentrations of 10% and 100% [105] and on human fibroblasts where it was observed a reduction in cell proliferation at concentrations of 100, 250, 500, 1000, and 2000 µg/mL [21].…”

Food waste as a carbon source in carbon quantum dots technology and their applications in food safety detection

“…In one study, CQDs were prepared to determine carmine in drinks with dried lemon peel as carbon source. Excessive amount of carmine added to food products causes damage to human health (Zippelius, et al, 2013). The CQDs were made by heating at 200℃ for 6h.…”