## 3 Results
### Tencytes Proliferation in xCELLigence System
#### 3.1.4. Interaction Between Ascorbic Acid and Dexamethasone  
Three concentrations of dexamethasone and ascorbic acid were cross-matched to see their effects on tenocytes proliferation among donors.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & \multirow{2}{*}{**Control**} & \multicolumn{4}{c}{**Ascorbic Acid**} & \multicolumn{4}{c}{**Dexamethasone**} \\ \cline{3-8}  & & **50 ug/mL** & **250 ug/mL** & **500 ug/mL** & **0.5 mg/mL** & **2.5 mg/mL** & **5 mg/mL** \\ \hline Young Donor & 2.21 \(\pm\) 0.22 & 2.5 \(\pm\) 0.08 & 1.52 \(\pm\) 0.17 & 0.61 \(\pm\) 0.36 & 2.62 \(\pm\) 0.28 & 0.47 \(\pm\) 0.05 & \(-\)0.14 \(\pm\) 0.05 \\ Old Donor & 2.47 \(\pm\) 0.31 & 2.46 \(\pm\) 0.12 & 1.94 \(\pm\) 0.34 & 0.67 \(\pm\) 0.3 & 2.82 \(\pm\) 0.1 & 0.54 \(\pm\) 0.06 & \(-\)0.17 \(\pm\) 0.05 \\ \(p\) Values & 1 & 1 & 0.2 & 1 & 1 & 1 & 1 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Cell index at 190 h when tenocytes were exposed to ascorbic acid and dexamethasone in young and old donors.  
Figure 4: Real-time changes of cell index when tenocytes were exposed to different concentrations of dexamethasone. (**a**) Cell index when tenocytes were exposed to 0.5, 2.5, and 5 mg/mL dexamethasone in the 20-year-old patient. (**b**) Cell index when tenocytes were exposed to 0.5, 2.5, and 5 mg/mL dexamethasone in the 41-year-old patient. * \(p\) < 0.05.  
Dexamethasoneone 0.5 mg/mL and Three Concentrations of Ascorbic Acid  
CI increased significantly when 50 and 250 ug/mL ascorbic acid were used in combination with 0.5 mg/mL dexamethasone (\(p\) = 0) in both the young and the old donor's tenocytes (Figure 5a,b). They failed to demonstrate any benefit in proliferation when 500 ug/mL ascorbic acid and 0.5 mg/mL dexamethasone were used together (\(p\) = 1 for young and 0.75 for old tenocytes) (Figure 5a,b). When the same conditions were compared between donors, tenocytes from the old donor demonstrated significantly better proliferation in 0.5 mg/mL dexamethasone with 250 ug/mL ascorbic acid and 0.5 mg/mL dexamethasone with 500 ug/mL ascorbic acid group compared to the young donor (\(p\) = 0 and \(p\) = 0.03) (Table 2).  
and 250 \(\upmu\)g/mL ascorbic acid when used with 2.5 mg/mL dexamethasone. The lowest proliferation was observed in 2.5 mg/mL dexamethasone with 500 \(\upmu\)g/mL ascorbic acid group (\(p\) = 0.02), which confirmed the hypothesis that tenocytes from the old donor had more susceptibility towards a specific concentration of dexamethasone and ascorbic acid (Figure 6b).  
Dexamethasone 5 mg/mL and Three Concentrations of Ascorbic Acid  
All tenocytes proliferations were close to zero. This implied the cytotoxicity of 5 mg/mL dexamethasone could not be alleviated by all three concentrations of ascorbic acid in both donors (Figure 7a,b). No significant difference was found between groups (\(p\) = 1).  
Figure 6: Real-time changes of cell index when tenocytes were exposed to 2.5 mg/mL of dexamethasone and different concentrations of ascorbic acid. (**a**) Cell index when tenocytes were exposed to 50, 250, and 500 \(\upmu\)g/mL ascorbic acid in the 20-year-old patient. (**b**) Cell index when tenocytes were exposed to 50, 250, and 500 \(\upmu\)g/mL ascorbic acid in the 41-year-old patient. \({}^{*}p<0.05\).