Sex Differences in Central Expression and Effects of Brain-Derived Neurotrophic Factor

Haifei Shi

Department of Biology, Miami University

International Conference on Endocrinology

October 22, 2014

VMH

3V

BDNF

Leptin

ARC

POMC

Arcuate melanocortin system

Xu, et al., Nat Neurosci 2003 Komori, et al., Neuroscience 2006Wang, et al., AJP 2007, 2010

BDNF

+

+

Expenditure Intake

Lepr

BDNF conditional deficient mice

Transgenic mouse models

Rios, et al., Mol Endocrinol 2001

ControlBdnf deficient

VMH

3V

ARC

Asarian & Geary, Philos T Roy Soc B 2006

Estradiol regulates food intake

estradiol

Expenditure Intake

100 mm

Xu, et al., Nat Neurosci 2003

BDNF in the hypothalamus

BDNF

BDNF and estrogen receptor alpha (ERα) in the hypothalamus

ERa

Arc

VMH

100 mm

Shi Lab

Colocalization of ERα and BDNF in the VMH

ERα: brownBDNF: blueBlurton-Jones, et al., J Comp Neurol 2004

ER α: brown (DAB)BDNF: blue black (nickel-enhanced DAB)BDNF + ER αShi Lab

VMH

3V

BDNF

Leptin

ARC estrogen

POMC

Expenditure Intake

estradiol

Potential regulation of BDNF by estradiol

Hypothesis: Central BDNF expression and action are regulated by estradiol.

Q1: Is central BDNF expression regulated by estradiol?Q2: Is central BDNF action regulated by estradiol?

VMH

3V

BDNF

Leptin

ARC

POMC

Expenditure Intake

estradiol

Hypothesis: Central BDNF expression and action are regulated by estradiol.

Q1: Is central BDNF expression regulated by estradiol?Q2: Is central BDNF action regulated by estradiol?

VMH

3V

BDNF

Leptin

ARC

POMC

Expenditure Intake

estradiol

Ovariectomy (OVX)

Estradiol (E2; subcu)

Q1: Is central BDNF expression regulated by estradiol? (1) Does ovariectomy (OVX) or estradiol (E2) replacement modulate VMH BDNF gene expression?

Experiment groups

Sham-Oil OVX-Oil ad libOVX-Oil pairfeed (PF) (pairfeed to Sham-Oil)OVX-E2

0 2 4 6 8 10 12 14 16 18 20 22200

220

240

260

280

300 Sham-Oil

OVX-Oil

OVX-Oil PF

OVX-E2

*

Days

Bo

dy

wei

gh

t (g

)

0 2 4 6 8 10 12 14 16 18 20 226

8

10

12

14

16

18

20

Sham-Oil

OVX-Oil

OVX-E2

*#

Days

Fo

od

inta

ke (

g)

Sham-O

il

OVX-Oil

OVX-Oil

PF

OVX-E2

0

10

20

30

40

50

60

* *

Pla

sma

estr

adio

l lev

el(p

g/m

l)

Sham-O

il

OVX-Oil

OVX-Oil

PF

OVX-E2

0

50

100

150

* *

Bdnf

mR

NA

lev

el i

n V

MH

(% o

f S

ham

fem

ales

)

Zhu, Liu, et al., Horm Behav 2014

Q1: Is central BDNF expression regulated by estradiol? (1) Does ovariectomy (OVX) or estradiol (E2) replacement modulate VMH BDNF gene expression?

(2) Do male and female rats have different BDNF expression? Does estrous cycle modulate VMH BDNF gene expression?Experiment groups (Ordered 10-week old male and female rats, sacrificed at 12-week of age)

Daily Food Intake

Male D-P P-E E-M M-D10

15

20

25

Fo

od

In

take

(g

)

Dairy Body Weight

Male D-P P-E E-M M-D200

250

300

350

400

Bo

dy

wei

gh

t (g

)Q1: Is central BDNF expression regulated by estradiol?

11

12

13

14

15

Diest

rus

Proest

rus

Estru

s

Mete

stru

s

Diest

rus

*

Fo

od

inta

ke (

g)

240

242

244

246

248

Diest

rus

Proest

rus

Estru

s

Mete

stru

s

Bo

dy

wei

gh

t (g

)

Mal

e

Diest

rus

Proes

trus

Estru

s

Met

estru

s0

10

20

30

40

50

60*

**

Pla

sma

estr

adio

l lev

el(p

g/m

l)M

ale

Diest

rus

Proes

trus

Estru

s

Met

estru

s0

50

100

150

200

250 *

Bdnf

mR

NA

lev

el i

n V

MH

(% o

f m

ale)

Zhu, Liu, et al., Horm Behav 2014; Liu, Zhu, et al., Physiol Behav 2014

Summary 1Q1: Is central BDNF expression regulated by estradiol?

BDNF gene expression is regulated in an estradiol-sensitive manner.

• OVX decreases BDNF gene expression; reversed by estradiol replacement.

• Estrous female rats have greater BDNF expression than males.

• BDNF expression is dynamically regulated across estrous cycle with a temporal elevation at estrous phase.

Hypothesis: Central BDNF expression and action are regulated by estradiol.

Q1: Is central BDNF expression regulated by estradiol?Q2: Is central BDNF action regulated by estradiol?

VMH

3V

BDNF

Leptin

ARC

POMC

Expenditure Intake

estradiol

Clegg, et al., Diabetes 2006de Souza, et al., Eur J Pharmacol 2011Gao, et al., Nat Med 2007

Experiment groups

Male-OilSham-OilOVX-Oil ad libOVX-Oil pairfeed (PF) (pairfeed to Sham-Oil Female)OVX-E2

Q2: Is central BDNF action regulated by estradiol?

(1) Is central BDNF’s anorexic effect regulated by estradiol?

Experiment procedure

Lights i3vt Lights out; 4-hour 24-hourOn 0.1μg, 0.3μg food intake food intake

BDNF orvehicle

LightDarkLight

Plasma Estradiol Levels

Mal

e

Sham F

emal

e

OVX-Oil

Femal

e

OVX-Oil

PF Fem

ale

OVX-E2

Femal

e0

20

40

60

* **

Pla

sma

E2

leve

l (p

g/m

l)

Baseline 24-Hour Food Intake

Mal

e Sham

-Oil

Femal

e Sham

-Oil

OVX-Oil

OVX-Oil

PF

OVX-E2

0

5

10

15

20

25 *

Fo

od

Inta

ke (

g)

Baseline Body Weights

Mal

e Sham

-Oil

Femal

e Sham

-Oil

OVX-Oil

OVX-Oil

PF

OVX-E2

200

250

300

350

400 *

Bo

dy

Wei

gh

t (g

)

#

Zhu, Liu, et al., Horm Behav 2014

Q2: Is central BDNF action regulated by estradiol?

(1) Is central BDNF’s anorexic effect regulated by estradiol?

Mal

e Sham

-Oil

Femal

e Sham

-Oil

0

2

4

6

8 0 g BDNF0.1 g BDNF0.3 g BDNF

*

* *

4-h

ou

r fo

od

inta

ke (

g)

Mal

e Sham

-Oil

Femal

e Sham

-Oil

02468

1012141618202224 0 g BDNF

0.1 g BDNF0.3 g BDNF

*

* *

24-h

ou

r fo

od

inta

ke (

g)

Zhu, Liu, et al., Horm Behav 2014

Q2: Is central BDNF action regulated by estradiol?

(1) Is central BDNF’s anorexic effect regulated by estradiol?

OVX-E2

OVX-Oil

PF

OVX-Oil

0

2

4

6 0 g BDNF0.1 g BDNF0.3 g BDNF

* *

**

4-h

ou

r fo

od

inta

ke (

g)

OVX-E2

OVX-Oil

PF

OVX-Oil

02468

101214161820

0 g BDNF0.1 g BDNF0.3 g BDNF

* **

*

24-h

ou

r fo

od

inta

ke (

g)

Q2: Is central BDNF action regulated by estradiol?

(2) Does ovariectomy or estradiol replacement regulate BDNF’s

anorexic effect?

Zhu, Liu, et al., Horm Behav 2014

Experiment procedure

Lights i3vt Lights out; 24-hour On 0.1μg energy expenditure

BDNF or vehicle

LightDarkLight

Q2: Is central BDNF action regulated by estradiol?

(3) Is central BDNF’s effect on energy expenditure different between

males and females?

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

15

20

25

30

35

40

saline0.1 g BDNF

*

**

Time (hour)

VO

2 m

l/kg

BW

/min

Dark Light0

10

20

30

40

saline0.1 g BDNF

**

VO

2 m

l/kg

BW

/min

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 2415

20

25

30

35

40saline0.1 g BDNF

Time (hour)

VO

2 m

l/kg

BW

/min

Dark Light0

10

20

30

40 saline0.1 g BDNF

VO

2 m

l/kg

BW

/min

Male Rats

Dark Light

0.7

0.8

0.9

1.0 saline

0.1 g BDNF

RQ

*

Female Rats

Dark Light

0.7

0.8

0.9

1.0 saline

0.1 g BDNF

RQ

* *

Liu, Zhu, Shen, Shi. Unpublished.

Q2: Is central BDNF action regulated by estradiol?

(3) Is central BDNF’s effect on energy expenditure different between

males and females?

Summary 2Q2: Is central BDNF’s action regulated by estradiol?

• Estrous female rats respond to a lower dose of BDNF than male rats to reduce food intake.

• Estradiol-replaced OVX rats respond to a lower dose of BDNF than oil-injected OVX rats to reduce food intake.

• Central administration of a low dose (0.1 µg) of BDNF increased energy expenditure in female but not male rats.

• Central administration of a low dose (0.1 µg) of BDNF increased lipid oxidation during dark and light phases in females and only during light phase in males.

VMH

3V

BDNF

Leptin

ARC

POMC

Expenditure Intake

estradiol

ConclusionEstradiol increases BDNF central expression and action.

Acknowledgement

Graduate students:Zheng ZhuXian LiuMinqian ShenShiva Senthil-Kumar

Undergraduate students:Ashley Goudjo-AkoSean Pugh

SDG4520028

R15DK090823

Funding:

Summer research fellowship

Undergraduate research funding