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Osteocompatibility of biofilm inhibitors.

Rawson M, Haggard W, Jennings JA - Open Orthop J (2014)

Bottom Line: Farnesol and dFBr induced cytotoxic responses within the reported biofilm inhibitory concentration range and low doses of dFBr were found to inhibit osteoblast differentiation.At high concentrations, such as those that may be present after local delivery, many of these biofilm inhibitors can have effects on cellular viability and osteoblast function.Concentrations at which negative effects on osteoblasts occur should serve as upper limits for delivery to orthopaedic trauma sites and guide development of these potential therapeutics for orthopaedics.

View Article: PubMed Central - PubMed

Affiliation: Biomedical Engineering, University of Memphis, 330 Engineering Technology Building, Memphis, TN 38152, USA.

ABSTRACT
The demand for infection prevention therapies has led to the discovery of several biofilm inhibitors. These inhibiting signals are released by bacteria, fungi, or marine organisms to signal biofilm dispersal or disruption in Gram-positive, Gram-negative, and fungal microorganisms. The purpose of this study was to test the biocompatibility of five different naturally-produced biofilm chemical dispersal and inhibition signals with osteoblast-like cells: D-amino acids (D-AA), lysostaphin (LS), farnesol, cis-2-decenoic acid (C2DA), and desformyl flustrabromine (dFBr). In this preliminary study, compatibility of these anti-biofilm agents with differentiating osteoblasts was examined over a 21 days period at levels above and below concentrations active against bacterial biofilm. Anti-biofilm compounds listed above were serially diluted in osteogenic media and added to cultures of MC3T3 cells. Cell viability and cytotoxicity, after exposure to each anti-biofilm agent, were measured using a DNA assay. Differentiation characteristics of osteoblasts were determined qualitatively by observing staining of mineral deposits and quantitatively with an alkaline phosphatase assay. D-AA, LS, and C2DA were all biocompatible within the reported biofilm inhibitory concentration ranges and supported osteoblast differentiation. Farnesol and dFBr induced cytotoxic responses within the reported biofilm inhibitory concentration range and low doses of dFBr were found to inhibit osteoblast differentiation. At high concentrations, such as those that may be present after local delivery, many of these biofilm inhibitors can have effects on cellular viability and osteoblast function. Concentrations at which negative effects on osteoblasts occur should serve as upper limits for delivery to orthopaedic trauma sites and guide development of these potential therapeutics for orthopaedics.

No MeSH data available.


Related in: MedlinePlus

Graphical representation comparing day 3 ALP/DNA production for control groups and sub-toxic concentrations of test groups.Data are represented as mean ± standard deviation; * indicates significant difference compared to osteogenic control, # indicates significantdifference compared to osteogenic ethanol control.
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Figure 4: Graphical representation comparing day 3 ALP/DNA production for control groups and sub-toxic concentrations of test groups.Data are represented as mean ± standard deviation; * indicates significant difference compared to osteogenic control, # indicates significantdifference compared to osteogenic ethanol control.

Mentions: ALP, an early indicator of osteogenic differentiation, peaked around day 3 for the osteogenic and non-osteogenic control groups (Fig. 3a). The osteogenic control group with ethanol had a decreased day 3 ALP production, but had higher ALP/DNA ratios than the other groups after day 3 and continued to positively increase throughout the 21day study. The D-AA test samples decreased in ALP/DNA production over time in comparison to the osteogenic control groups with ethanol (Fig. 3b). No significant differences from the osteogenic control group were detected in the evaluated concentrations of lysostaphin (Fig. 3c). Farnesol stimulated early significant increases in ALP/DNA on day 3 compared to both osteogenic control groups with and without ethanol, then continued to decrease in ALP production throughout the remainder of the 21 day study (Fig. 3d). In a similar fashion to farnesol, the C2DA test group ALP/DNA ratio peaked at day 3 at a significantly higher value than the osteogenic control groups, but steadily declined over the remainder of the 21 day time period (Fig. 3e). The farnesol and C2DA test groups displayed high variability, which may correspond to higher variability in the DNA levels. dFBr significantly lowered ALP production in the early stages of exposure to the cells, but peaked at levels similar to the osteogenic control by day 14 (Fig. 3f). With day 3 representing the peak in control ALP production, only farnesol, C2DA, non-osteogenic media, and osteogenic media containing ethanol sig-nificantly differed from the osteogenic positive control (Fig. 4).


Osteocompatibility of biofilm inhibitors.

Rawson M, Haggard W, Jennings JA - Open Orthop J (2014)

Graphical representation comparing day 3 ALP/DNA production for control groups and sub-toxic concentrations of test groups.Data are represented as mean ± standard deviation; * indicates significant difference compared to osteogenic control, # indicates significantdifference compared to osteogenic ethanol control.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4260234&req=5

Figure 4: Graphical representation comparing day 3 ALP/DNA production for control groups and sub-toxic concentrations of test groups.Data are represented as mean ± standard deviation; * indicates significant difference compared to osteogenic control, # indicates significantdifference compared to osteogenic ethanol control.
Mentions: ALP, an early indicator of osteogenic differentiation, peaked around day 3 for the osteogenic and non-osteogenic control groups (Fig. 3a). The osteogenic control group with ethanol had a decreased day 3 ALP production, but had higher ALP/DNA ratios than the other groups after day 3 and continued to positively increase throughout the 21day study. The D-AA test samples decreased in ALP/DNA production over time in comparison to the osteogenic control groups with ethanol (Fig. 3b). No significant differences from the osteogenic control group were detected in the evaluated concentrations of lysostaphin (Fig. 3c). Farnesol stimulated early significant increases in ALP/DNA on day 3 compared to both osteogenic control groups with and without ethanol, then continued to decrease in ALP production throughout the remainder of the 21 day study (Fig. 3d). In a similar fashion to farnesol, the C2DA test group ALP/DNA ratio peaked at day 3 at a significantly higher value than the osteogenic control groups, but steadily declined over the remainder of the 21 day time period (Fig. 3e). The farnesol and C2DA test groups displayed high variability, which may correspond to higher variability in the DNA levels. dFBr significantly lowered ALP production in the early stages of exposure to the cells, but peaked at levels similar to the osteogenic control by day 14 (Fig. 3f). With day 3 representing the peak in control ALP production, only farnesol, C2DA, non-osteogenic media, and osteogenic media containing ethanol sig-nificantly differed from the osteogenic positive control (Fig. 4).

Bottom Line: Farnesol and dFBr induced cytotoxic responses within the reported biofilm inhibitory concentration range and low doses of dFBr were found to inhibit osteoblast differentiation.At high concentrations, such as those that may be present after local delivery, many of these biofilm inhibitors can have effects on cellular viability and osteoblast function.Concentrations at which negative effects on osteoblasts occur should serve as upper limits for delivery to orthopaedic trauma sites and guide development of these potential therapeutics for orthopaedics.

View Article: PubMed Central - PubMed

Affiliation: Biomedical Engineering, University of Memphis, 330 Engineering Technology Building, Memphis, TN 38152, USA.

ABSTRACT
The demand for infection prevention therapies has led to the discovery of several biofilm inhibitors. These inhibiting signals are released by bacteria, fungi, or marine organisms to signal biofilm dispersal or disruption in Gram-positive, Gram-negative, and fungal microorganisms. The purpose of this study was to test the biocompatibility of five different naturally-produced biofilm chemical dispersal and inhibition signals with osteoblast-like cells: D-amino acids (D-AA), lysostaphin (LS), farnesol, cis-2-decenoic acid (C2DA), and desformyl flustrabromine (dFBr). In this preliminary study, compatibility of these anti-biofilm agents with differentiating osteoblasts was examined over a 21 days period at levels above and below concentrations active against bacterial biofilm. Anti-biofilm compounds listed above were serially diluted in osteogenic media and added to cultures of MC3T3 cells. Cell viability and cytotoxicity, after exposure to each anti-biofilm agent, were measured using a DNA assay. Differentiation characteristics of osteoblasts were determined qualitatively by observing staining of mineral deposits and quantitatively with an alkaline phosphatase assay. D-AA, LS, and C2DA were all biocompatible within the reported biofilm inhibitory concentration ranges and supported osteoblast differentiation. Farnesol and dFBr induced cytotoxic responses within the reported biofilm inhibitory concentration range and low doses of dFBr were found to inhibit osteoblast differentiation. At high concentrations, such as those that may be present after local delivery, many of these biofilm inhibitors can have effects on cellular viability and osteoblast function. Concentrations at which negative effects on osteoblasts occur should serve as upper limits for delivery to orthopaedic trauma sites and guide development of these potential therapeutics for orthopaedics.

No MeSH data available.


Related in: MedlinePlus