Effect of Amplitude and Frequency of Cyclic Tensile Strain on the Inhibition of MMP-1 mRNA Expression in Tendon Cells: An In Vitro Study

Aim: In this study, curcumin was encapsulated in niosomes (Nio-Curc) to increase its effectiveness for the treatment of asthma. Materials & methods: The formulation underwent various physicochemical characterization experiments, an in vitro release study, molecular simulations and was evaluated for in vitro anti-inflammatory activity. Results: Results showed that Nio-Curc had a mean particle size of 284.93 ± 14.27 nm, zeta potential of -46.93 and encapsulation efficacy of 99.62%, which demonstrates optimized physicochemical characteristics. Curcumin release in vitro could be sustained for up to 24 h. Additionally, Nio-Curc effectively reduced mRNA transcript expression of pro-inflammatory markers; IL-6, IL-8, IL-1β and TNF-α in immortalized human airway basal cell line (BCi-NS1.1). Conclusion: In this study, we have demonstrated that Nio-Curc mitigated the mRNA expression of pro-inflammatory markers in an in vitro study, which could be applied to treatment of asthma with further studies.

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Differential regulation of gene expression in isolated tendon fascicles exposed to cyclic tensile strain in vitro

Journal of Applied Physiology ◽

10.1152/japplphysiol.90981.2008 ◽

2009 ◽

Vol 106 (2) ◽

pp. 506-512 ◽

Cited By ~ 40

Author(s):

Eijiro Maeda ◽

Julia C. Shelton ◽

Dan L. Bader ◽

David A. Lee

Keyword(s):

Mrna Expression ◽

Incubation Period ◽

Tensile Strain ◽

Cyclic Strain ◽

Type Iii Collagen ◽

Type I ◽

Cyclic Tensile Strain ◽

Type Iii ◽

Catabolic Genes

Mechanical stimulus is a regulator of tenocyte metabolism. The present study investigated temporal regulation of the expression of selected genes by tenocytes in isolated fascicles subjected to tensile strain in vitro. Cyclic tensile strain with a 3% amplitude superimposed on a 2% static strain was provided for 10 min, followed by either an unstrained period or continuous cyclic strain until the end of a 24-h incubation period. mRNA expression of selected anabolic and catabolic genes were evaluated with quantitative PCR at 10 min, 1 h, 6 h, and 24 h. The application of 6-h cyclic strain significantly upregulated type III collagen mRNA expression in strained fascicles compared with unstrained controls, but no alterations were observed in mRNA expression of type I collagen and biglycan. Significant downregulation in the expression of the decorin core protein was observed in fascicles subjected to 24-h cyclic strain. MMP3 and MMP13 expression levels were upregulated by the application of 10 min of cyclic strain, followed by a progressive downregulation until the end of the incubation period in both the absence and the presence of the continuing cyclic strain. Accordingly, alterations in the expression of anabolic genes were limited to the upregulation of type III collagen by prolonged exposure to cyclic strain, whereas catabolic genes were upregulated by a small number of strain cycles and downregulated by a prolonged cyclic strain. These findings demonstrate distinctive patterns of mechanoregulation for anabolic and catabolic genes and help our understanding of tenocyte response to mechanical stimulation.

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