To quantify the rate of superoxide anion production over time in
response to the different treatment conditions, sigmoidal and linear
equations were fitted to the data (See Materials & Methods). Figure 3b
consists of the data fitted to the sigmoidal equation for AA and
combination treatment, and linear equation for control, metformin, and
sulindac treatments. The nonlinear fitting used for AA and the
combination treatment demonstrates a greater increase in the
O2•− production rate in the
aforementioned groups in comparison to the remaining groups. This can be
further justified by Table 1, where slopes of AA and the combination of
metformin and sulindac are notably greater than the linear slopes. Table
2 depicts the percent change between the slopes of the control group and
the treatment groups, including AA. The percent change between the
control and positive control group is the greatest (75.93%), followed
by the difference between the control and combination of metformin and
sulindac groups (33.22%), control group and sulindac (7.88%), and
lastly control group and metformin (5.48%). The highest difference was
expected, as AA is the positive control, though the greater difference
in percent change between control and combination group, compared to
control and the treatments alone indicates the role of the drug
combination in superoxide production increases over time.
The slopes of red channel fluorescence intensity for each group are
compared to one another statistically in Figure 4 and showed significant
changes in the positive control and combined treatment compared to the
control group. In these treatment cases, there was a large difference in
the rate of superoxide production over time with respect to the control
group, reflecting the effects of the drugs on the mitochondria and its
processes.