Meredith Rutledge presented research on the effects of a cytochrome P450 2B6 (Cyp2b) gene knockout in mice fed normal diet (ND) or high fat diet (HFD). Behavioral tests found HFD increased boldness in wild type females but ND increased boldness in wild type males. Weight gain was affected by both diet and genotype in males, and diet affected weight gain in females. Fasting blood glucose levels increased in all mice on HFD over time, suggesting diet and lack of Cyp2b impacts glucose metabolism and susceptibility to diet-induced obesity and diabetes. The conclusion was that diet, genotype, and lack of Cyp2b each influence weight gain and glucose levels.

1. 2015 Summer Research
Presentation
By Meredith Rutledge

2. Cytochrome P450 (CYPs)
• Hemoproteins (superfamily of proteins
containing a heme cofactor)
• Terminal oxidase enzymes in electron chains
• More than 21,000 identified CYP proteins
Cytochrome P450 Oxidase

3. Cytochrome P450 2B6
• Monooxygenase
• Catalyze many reactions involved in drug
metabolism and synthesis of cholesterol,
steroids and other lipids
• CYP2B localized in endoplasmic reticulum
• Expression induced by phenobarbital
• Known to metabolize some xenobiotics (anti-
cancer drugs)

4. Hypothesis: Cyp2b-null mice will be
more susceptible to a HFD in
comparison to the WT group

5. W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-null F
N
D
(B
)
2b-null F
N
D
(A
)
2b-null F
H
FD
(B
)
2b-null F
H
FD
(A
)
0
100
200
300
400
500
Total movements females
Movements
B=before treatment
A=after treatment
W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-null F
N
D
(B
)
2b-null F
N
D
(A
)
2b-null F
H
FD
(B
)
2b-null F
H
FD
(A
)
0
2
4
6
Outside:Inside movements females
Ratioofmovements
B=before treatment
A=after treatment
*
W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-nullF
N
D
(B
)
2b-nullF
N
D
(A
)
2b-nullF
H
FD
(B
)
2b-nullF
H
FD
(A
)
0
100
200
300
400
Total outside movements females
Movements
B=before treatment
A=after treatment
W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-nullF
N
D
(B
)
2b-nullF
N
D
(A
)
2b-nullF
H
FD
(B
)
2b-nullF
H
FD
(A
)
0
50
100
150
Total inside movement females
Movements
B=before treatment
A=after treatment
*
Activity Study on Cyp2b-null and BL6 (WT) Female Mice
Treatment HFD and ND
HFD caused
increase in
boldness for WT
females

6. W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-null M
N
D
(B
)
2b-null M
N
D
(A
)
2b-null M
H
FD
(B
)
2b-null M
H
FD
(A
)
0
200
400
600
Total movements males
Movements
B=before treatment
A=after treatment
** *
W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-null M
N
D
(B
)
2b-null M
N
D
(A
)
2b-null M
H
FD
(B
)
2b-null M
H
FD
(A
)
0
1
2
3
4
5
Outside:Inside movements males
Ratioofmovements
B=before treatment
A=after treatment
W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-nullM
N
D
(B
)
2b-nullM
N
D
(A
)
2b-nullM
H
FD
(B
)
2b-nullM
H
FD
(A
)
0
100
200
300
400
Total outside movements males
Movements
B=before treatment
A=after treatment
* *
W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-nullM
N
D
(B
)
2b-nullM
N
D
(A
)
2b-nullM
H
FD
(B
)
2b-nullM
H
FD
(A
)
0
50
100
150
200
Total inside movement males
Movements
B=before treatment
A=after treatment
*
Activity Study on Cyp2b-null and BL6 (WT) Male Mice
Treatment HFD and ND
Decrease in total
activity due to ND
and HFD treatment

7. W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-null F
N
D
(B
)
2b-null F
N
D
(A
)
2b-null F
H
FD
(B
)
2b-null F
H
FD
(A
)
-50
0
50
100
150
200
Total movements females
Movements
B=before treatment
A=after treatment
W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-null F
N
D
(B
)
2b-null F
N
D
(A
)
2b-null F
H
FD
(B
)
2b-null F
H
FD
(A
)
-200
0
200
400
600
800
Time to move from home females
Time
B=before treatment
A=after treatment
W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-nullF
N
D
(B
)
2b-nullF
N
D
(A
)
2b-nullF
H
FD
(B
)
2b-nullF
H
FD
(A
)
-100
0
100
200
300
400
Total time out of home females
TIme(s)
B=before treatment
A=after treatment
W
T-F
N
D
(B
)
W
T-F
N
D
(A
)
W
T-F
H
FD
(B
)
W
T-F
H
FD
(A
)
2b-nullF
N
D
(B
)
2b-nullF
N
D
(A
)
2b-nullF
H
FD
(B
)
2b-nullF
H
FD
(A
)
0
2
4
6
8
# of different spaces visited females
#differentspaces
B=before treatment
A=after treatment
Boldness Study on Cyp2b-null and BL6 (WT) Female Mice
Treatment HFD and ND

8. W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-null M
N
D
(B
)
2b-null M
N
D
(A
)
2b-null M
H
FD
(B
)
2b-null M
H
FD
(A
)
-50
0
50
100
150
Total movements males
Movements
B=before treatment
A=after treatment
W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-nullM
N
D
(B
)
2b-nullM
N
D
(A
)
2b-nullM
H
FD
(B
)
2b-nullM
H
FD
(A
)
-200
0
200
400
600
800
Time to move from home males
TIme(s)
B=before treatment
A=after treatment
W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-nullM
N
D
(B
)
2b-nullM
N
D
(A
)
2b-nullM
H
FD
(B
)
2b-nullM
H
FD
(A
)
0
100
200
300
400
Total time out of home males
TIme(s)
*
B=before treatment
A=after treatment
W
T-M
N
D
(B
)
W
T-M
N
D
(A
)
W
T-M
H
FD
(B
)
W
T-M
H
FD
(A
)
2b-nullM
N
D
(B
)
2b-nullM
N
D
(A
)
2b-nullM
H
FD
(B
)
2b-nullM
H
FD
(A
)
0
2
4
6
8
# of different spaces visited males
#differentspaces
B=before treatment
A=after treatment
ND treatment
increased
boldness in
WT
Boldness Study on Cyp2b-null and BL6 (WT) Male Mice
Treatment HFD and ND

9. W
eek
0W
eek
1W
eek
2W
eek
3W
eek
4W
eek
5W
eek
6W
eek
7W
eek
8
15
20
25
30
Females Weight vs Week
Weightmeasured(gm)
WT-F ND
WT-F HFD
Cyp2b-null F ND
Cyp2b-null F HFD
a=Cyp2b-null F HFD different than Cyp2b-null F ND
b=Cyp2b-null F HFD different than WT F HFD
C=WT F HFD different than WT F ND
a/c a a/c
a a/c a/c
W
eek
1W
eek
2W
eek
3W
eek
4W
eek
5W
eek
6W
eek
7W
eek
8
0
2
4
6
8
WeightChange(gm)
Females Weight Change vs Week
WT-F ND
WT-F HFD
Cyp2b-null F ND
Cyp2b-null F HFD
c
c
a/c
a/c
a/c
a
a=Cyp2b-null F HFD different than Cyp2b-null F ND
b=Cyp2b-null F HFD different than WT F HFD
C=WT F HFD different than WT F ND
a/c a/c
Diet had an
effect on the
weight gain
Weight Data on Cyp2b-null and BL6 (WT) Female Mice
Treatment HFD and ND

10. W
eek
0
W
eek
1
W
eek
2
W
eek
3
W
eek
4
W
eek
5
W
eek
6
W
eek
7
W
eek
8
20
25
30
35
40
Males Weight vs Week
Weightmeasured(gm)
WT-M ND
WT-M HFD
Cyp2b-null M ND
Cyp2b-null M HFD
a=Cyp2b-null M HFD different than Cyp2b-null M ND
b=Cyp2b-null M HFD different than WT M HFD
C=WT M HFD different than WT M ND
a/c a/c
a/c a/c
a/c
a/b/c
a/b/c
a/b/c
W
eek
1W
eek
2W
eek
3W
eek
4W
eek
5W
eek
6W
eek
7W
eek
8
0
5
10
15
WeightChange(gm)
Males Weight Change vs Week
WT-M ND
WT-M HFD
Cyp2b-null M ND
Cyp2b-null M HFD
a/c
a/c
a/c
a/c
a/c
a/c
a=Cyp2b-null M HFD different than Cyp2b-null M ND
b=Cyp2b-null M HFD different than WT M HFD
C=WT M HFD different than WT M ND
a/b/c
a/b/c
Genotype and diet
had an effect on
weight gain
Weight Data on Cyp2b-null and BL6 (WT) Male Mice
Treatment HFD and ND

11. W
T-F
N
D
W
T-F
H
FD
C
yp2b-null F
N
D
C
yp2b-null F
H
FD
0
100
200
300
400
Week 2 Female Glucose Levels
BloodGlucoselevel(mg/dl)
W
T-F
N
D
W
T-F
H
FD
C
yp2b-null F
N
D
C
yp2b-null F
H
FD
0
100
200
300
400
Week 5 Female Glucose Levels
BloodGlucoselevel(mg/dl)
W
T-F
N
D
W
T-F
H
FDC
yp2b-nullF
N
D
C
yp2b-nullF
H
FD
0
100
200
300
400
Week 8 Female Glucose Levels
BloodGlucoselevel(mg/dl)
Fasting Glucose Data on Cyp2b-null and BL6 (WT) Female Mice
Treatment HFD and ND

12. W
T-M
N
D
W
T-M
H
FD
C
yp2b-null M
N
D
C
yp2b-null M
H
FD
0
100
200
300
Week 2 Male Glucose Levels
BloodGlucoselevel(mg/dl)
W
T-M
N
D
W
T-M
H
FDC
yp2b-nullM
N
D
C
yp2b-nullM
H
FD
0
100
200
300
400
Week 5 Male Glucose Levels
BloodGlucoselevel(mg/dl)
W
T-M
N
D
W
T-M
H
FDC
yp2b-nullM
N
D
C
yp2b-nullM
H
FD
0
100
200
300
400
Week 8 Male Glucose Levels
BloodGlucoselevel(mg/dl)
*
Fasting Glucose Data on Cyp2b-null and BL6 (WT) Male Mice
Treatment HFD and ND

13. Conclusion
• Diet and genotype has an effect on weight
gain in males
• Diet had an effect on weight gain in female
mice
*Cyp2b-null plays a role in fat metabolism