Table 1 Results on changes in cellular, signaling and/or mechanical response to explants for hydrostatic and direct compression (Fig. 2). PG is proteoglycan; MMP is matrix metalloproteinases; # is number; h is hours; h/day is hours per day; − is decrease or inhibition; = is no change or status quo; + is increase; ++ is highest increase. *-symbol implies pressure converted from strain, which is added in brackets
From: What quantitative mechanical loading stimulates in vitro cultivation best?
Study | Cell source, cultivated construct, additive(s) | Magnitude (MPa) | Freq (Hz) | Loading (h/day) | Loading (# days) | Loading (total h) | Culture composition (change -, =, +) | mRNA response (change -, =, +) | Other findings (change -, =, +) |
|---|---|---|---|---|---|---|---|---|---|
Hydrostatic compression | |||||||||
Parkinnen 1993 (Parkkinen et al. 1993) | Bovine | 5 | 0.5 | 1.5 | 1 | 1.5 | + PG synthesis | Â | Â |
Explant | 0.25 | ||||||||
Fetal calf serum | 0.05 | = PG synthesis | Â | Â | |||||
| Â | 0.0167 | ||||||||
Direct compression | |||||||||
Li 2013 (Li et al. 2013) | Young Bovine Bruised Explant Serum free medium, 20Â g/ml ascorbic acid | 0.6-1.2* (10Â %) | 0.5 | 4 | 4 | 16 | + PG synthesis | + aggrecan | Control show better results compared to bruised explants |
+ collagen II | |||||||||
1.2-2.4* (20Â %) | ++ PG synthesis | ++ aggrecan | |||||||
++ collagen II | |||||||||
1.8-3.6* (30Â %) | + PG synthesis | + aggrecan | |||||||
= collagen II | |||||||||
Okuda 2013 (Okuda et al. 2013) | Young Bovine, Explant 20Â % Fetal bovine serum; 50Â mg/LÂ L-ascorbic acid | 0.6-1.2* (10Â %) | 1 | 3.5 | 5 | 17.5 | + sGAG | Â | + compressive modulus |
+ # of cells | |||||||||
Torzilli 1996 (Torzilli et al. 1996) | Bovine, Explant 10 % Fetal bovine serum; 50 μg/mL ascorbic acid | 1 | 1 | 24 | 1 | 24 | - PG synthesis |  |  |
Torzilli 2011 (Torzilli et al. 2011) | Bovine, Explant 10 % Fetal bovine serum; 50 μg/mL ascorbic acid | 0.5 (10 %) | 0.5 | 24 | 3 | 72 | = PG content | = MMP −3, −13 |  |