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Androgens:
They Don’t Just Make a Man
Out of You !
Aritro Sen Ph.D. University of Rochester School of Medicine & Dentistry
Department of Medicine
Division of Endocrinology & Metabolism
Androgens: They Don’t Just Make a Man Out of You !
Hyperandrogenism is Detrimental to Women’s Health
Androgen Priming may work…
The Egg Timer is about to (((Ring)))
If Too Many Androgens Cause
Unregulated Follicle Overgrowth,
Then What Happens When There Are
Too Few Androgen?
Shiina et.al., (2006) PNAS 103 ; 1 224-229
• Defective folliculogenesis
• Subfertility
• Premature ovarian Failure
Hu et.al., (2004) PNAS 101 ; 11209-11214
Androgen Receptor Knockout Mice
Have Decreased Fertility
Pituitary
Uterus
Ovary
Theca cells
Granulosa cells
Oocytes
The Follicle
Androgen Receptor is Expressed Throughout the Hypothalamus-Pituitary-Gonadal axis
Hypothalamus
AR loxp/loxp
+ XAmh-RII cre - GC
Generation of Granulosa cell (GC)-specific
Androgen Receptor knockout (ARKO)
Mouse Model
(From Dr. Guido Verhoeven) (From Dr. Martin Matzuk)
AR mRNA levels are low in the
granulosa cells (GC) of GC-ARKO mice
GC Pituitary Hypothalamus
WT GC AR +/- GC AR -/-
Rela
tive
expr
essi
on
of A
R m
RNA
*0
1
2
Sen et.al., Mol Endo 2010
+/+ +/- -/-AR
ActinGC
AR Protein levels are low in the
granulosa cells (GC) of GC-ARKO mice
Sen et.al., Mol Endo 2010
Sen et.al., Mol Endo 2010
WT
GC
AR -/
-
GCGC
40XGC
GC
**
*
*
* *
40X
20X
20X20XI II III
AR is Expressed in Theca but not Granulosa cells in GC-ARKO Mice
GC AR +/- GC AR -/-
Ovary
Uterus
GC-ARKO Mice Have Grossly Normal Reproductive Organs
Fertility Test
Genotype n Litter Pups Pups/litter Litter/female
GC AR -/- 8 17 48 2.82 ± 0.2* 2.13 ± 0.22*
WT 8 28 200 7.14 ± 0.29 3.5 ± 0.19
GC AR +/- 8 28 195 6.96 ± 0.28 3.5 ± 0.19
Genotype n Litter Pups Pups/litter Litter/female
GC AR -/- 6 10 16 1.6 ± 0.23* 1.66 ± 0.21*
WT 6 20 119 5.97 ± 0.25 3.33 ± 0.21
GC AR +/- 6 19 113 5.65 ± 0.42 3.16 ± 0.16
B. 24-25 week old animals
A. 8-9 week old animals
Sen et.al., Mol Endo 2010
GC-ARKO Mice Have Less Frequent and Smaller Litters
Why do GC-ARKO Mice Have Less Frequent Litters ?
Sen et.al., Mol Endo 2010
0 10 20 30Days
PDE
Stag
es o
f Es
trus
Cyc
le GC AR +/-
GC AR -/-PDE
GC-ARKO Mice Cycle Abnormally
GC AR +/-GC AR -/-
8-9 weeks 24-25 weeks0
5
10
Num
ber o
f oo
cyte
s
**
8-9 weeks 24-25 weeks0
510152025
Num
ber o
f sup
er-
ovul
ated
ooc
ytes
*
Why do GC-ARKO Mice Have Smaller Litter Size?
Sen et.al., Mol Endo 2010
GC-ARKO Mice Have Decreased Ovulation
GC AR +/- GC AR -/-0
20
40
FSH
(ng/
ml)
GC-ARKO Mice HavePremature Loss of Ovarian Reserve
(Premature Ovarian Failure)
*
Loss of AR in Granulosa Cells Results in:
• Less Frequent Ovulation
• Decreased number of oocytes ovulated
• Premature Ovarian Failure
Follicle Growth in the Ovary
% o
f fol
licle
s
Pr P PA A CL AF0
20
40
60
GC AR +/- GC AR -/-
GC-ARKO Mice Have a Normal Follicle Distribution at 4-5 Weeks
Pr P PA A CL AF0
20
40
60
**
*
*
CL
AFAFAF
AF AF
AF
AF
AF
A
A
A
ACL
CL
A
GC AR +/- GC AR -/-
GC-ARKO Mice Have Decreased Follicle Progression and Increased Follicle Atresia with Age
% o
f fol
licle
s
Folli
cle
diam
eter
(μm
)
D0 D40
150
300
*GC AR -/-GC AR +/+
Knockout of ARs in GCs Results in Slow Follicular Growth Rate
Sen et.al., Mol Endo 2010
The AR is Required for Follicle Progression from Pre-Antral to Antral Stage
Supplemental Fig 1
AOvaries from GC-ARKO Mice Have High
Rate of Apoptosis
Sen et.al., Mol Endo 2010
TUNNEL assay-detects DNA fragmentation that results from apoptosis
CleavedCaspase 3
Caspase 3]
-/-+/-
Gra
nulo
sa c
ells
Actin
ANDROGENS (Secret) :
Strong enough for a man but made for a woman
How do Androgens Promote Follicle Growth and Prevent Follicle Atresia?
How do Androgens Signal?
TF
Cellular Response
Gene ExpressionGenomic
Kinases
Androgens
AR
ARNonGenomic
Androgen Signaling
Extra-nuclear Androgen Signaling
Src
EGFR
ARMMP
ERK
Ras
Raf
MEK
Membrane bound
EGF ligands
Androgens
Sen et.al. JBC 2010; JCI 2012
PXNP-Y(Matrix Metalloproteinase)
EGFR
ARMMP Src
ERK
Ras
Raf
MEK
PXNP-Y
PXNP-Y P-S
Nucleus
PXNP-Y P-S
Androgens
DHT Promotes Paxillin Phophorylation & Phosphoserine-Paxillin Nuclear Localization
Sen et.al., JCI 2012
Media DHT
P-PXN
a b
PXN
PAXILLIN
AR
EGFR
ARMMP Src
ERK
Ras
Raf
MEK
PXNP-Y
PXNP-Y P-S
Nucleus
PXNP-Y P-S
Androgens
Media DHT
Nsp
si
RNA
PXN
si
RNA
1a 1b
2a 2b
Paxillin is Required for DHT-Induced ARNuclear Localization
Sen et.al., JCI 2012
Androgen Receptor
How do Androgens Promote Follicle Growth and Prevent Follicle Atresia?
Atresia
AR
Androgen-Induces miRNA-125b Expression
in Granulosa Cells
Sen et.al., unpublished
miR-125b
TATAAA
IIIIIIIV
ARE: 5’-GGTACAnnnTGTTCT-3’
5’ UTR region of miR-125b consists of
a TATA box and four potential AREs
5’ 3’
Media DHT0
5
10
15
GC Primary Culture (WT)
Rela
tive
expr
essi
on
of m
iRN
A125
b *
Sen et.al., unpublished
EGFR
ARMMP Src
ERK
Ras
Raf
MEK
PXNP-Y
PXNP-Y P-S
Nucleus
AR
PXNP-Y P-S
miRN-125b
Androgen-induced expression of miRNA-125b Requires the Extranuclear Pathway
Med
ia
DH
T
Flut
amid
e
U01
26
PXN
siRN
A
DHT
Rela
tive
expr
essi
on
of m
iRN
A125
b *
GC Primary Culture (WT)
0
4
8
EGF
Expression of miR-125b in GCs require a synergistic action between the nuclear
and extranuclear actions of ARs
Androgen ARExtranuclear
• MAPK• Paxillin
Nuclear
miRNA-125b expression(+)
Targets of miR-125b
• Bak1: Bcl-2 homologous killer • Bmf: Bcl2 modifying factor• Bax: bcl2 associated X protein• P53: tumor suppressor protein
miRNA-125b Suppresses Pro-Apoptotic Protein Expression in Granulosa Cells
BakBaxBmf
GAPDH
Nsp anti-
miR
125b
inhi
bito
r
DHT
P53
0
0.4
0.8
1.2
*
Rela
tive
expr
essi
on
of m
iRN
A125
b
GC Primary Culture (WT)
Nsp Anti-miR125b inhibitor
Sen et.al., unpublished
miRNA-125b expression
Pro-apoptotic proteins
Decreased Follicular atresia
Androgens
AIn GC-ARKO mice, miRNA-125b Expression Correlates with Apoptosis
B
CleavedCaspase 3
Caspase 3
]
-/-+/-
Gra
nulo
sa c
ells
Actin
WT KO0
0.5
1
1.5
Rela
tive
expr
essi
on
of m
iR-1
25b
*
WT KOBakBaxBmf
GAPDHP53
Androgen ARExtranuclear
• MAPK• Paxillin
Nuclear
miRNA-125b expression
Pro-apoptotic proteins
Decreased Follicular atresia
(+)
How do Androgens Promote Follicle Growth and Prevent Follicle Atresia?
Atresia
AR
Follicles Will Not Grow Without FSH
“Androgens augment FSH actions to promote follicular growth”
But How ?????
Androgens Increase Antral Follicle NumberIn Whole Ovary Organ Culture
Sen et.al., unpublished
0 10 25 1000
100
200
300
400 D0 D4
DHT (nM)
Fo
llic
ula
r di
amet
er (
μm
)
* *
Androgens Increase Growth of Follicles In Vitro
Sen et.al., unpublished
-DHT
+DHT
WT GC-ARKO0
0.6
1.2
Rela
tive
expr
essi
on
of F
SHR
mRN
A
WT KOFSHR
GAPDH
Androgens are not essential for FSHR expression
Sen et.al., unpublished
In Primary Granulosa Cells, Androgens Increase FSH Protein but not mRNA Expression
M DHTFSHR
GAPDH
M DHT0
0.6
1.2
Rela
tive
expr
essi
on
of F
SHR
mRN
A
GC Primary Culture (WT)
Sen et.al., unpublished
While androgens are not essential for FSHR expression, androgens can increase FSHR protein levels in a
transcription-independent (non-genomic) fashion
Androgen AR
AR Signaling in Granulosa Cells Stimulates FSH Receptor Expression,
which Mediates Follicle Growth
FSH Receptor
Increased Pre-AntralFollicle Growth
Extranuclear
• MAPK• Paxillin
Androgen Treatment Increases the Sensitivity Of Follicles Towards FSH Actions
0
25
50
FSH (ng/ml)0 1 10 100
Perc
ent o
f Fol
licle
s
- DHT
+ DHT
Antral Follicle Count
AR Signaling in Granulosa Cells Blocks Apoptosis and Promotes Follicle Growth
Androgen AR FSHR Increased Pre-Antral
Follicle GrowthExtranuclear
• MAPK• Paxillin
Nuclear
miRNA-125b expression
Pro-apoptotic proteins Decreased Follicular atresia
DHEA in DOR Patients
DHEA
Testosterone
Androstenedione
Androstenediol
17b
HSD
Estradiol
CYP19Estrone
3bHSD
CYP193bHSD 17b
HSD
17b
HSD
AR
FSH (10ng/ml)DHEA (100nM) Flutamide (100nM)
0
10
20
FSH FSH +DHEA
FSH + DHEA+ Flutamide
Perc
ent o
f Fol
licle
s
Antral Follicle Count
DHEA Mimics DHT Effects on Follicular Development
M DHT0
4
8
12
Rela
tive
expr
essi
on o
f AM
H m
RNA
GC culture (WT)*
WT GC-ARKO0
0.7
1.4
*
Androgens induce AMH expression in granulosa cells
Sen et.al., unpublished
DHEA in DOR Patients- IVF
DHEA
DHEA
Testosterone
Androstenedione
Androstenediol
17b
HSD
Estradiol
CYP19Estrone
3bHSD
AR
AMH expression
Follicular survival
FSH sensitivity
# of oocytes retrieved during IVF
AFC
3bHSD CYP19
17b
HSD
17b
HSD
“Balance is Key”Mr. Miyagi…….Karate kid
Too much androgens: PCOSToo few androgen: Diminished Ovarian Reserve
Acknowledgements
Funding
NIH
University of Rochester
Foundation of Reproductive Medicine
Stephen R Hammes MD PhD
Melissa Rasar MD PhD
Amber West
Liliana Carbajal PhD
Kristen Evaul PhD
James Deng PhD
Tamara Strauss PhD
Francesco Caiazza PhD
Anindita Biswas MS
Hen Prizant
Ismary DeCastro MD
Allison Light
CHR
Norbert Gleicher MD
David Barad MD
Ho-Joon Lee PhD
Tamar Michaeli PhD
Aya Shohat-Tal PhD
Baylor College of Medicine
Martin Matzuk PhD
Catholic University of Leuven, Belgium
Guido Verhoeven PhD
Now….. who says I don’t have ANDROGENS!!!!!!
THANK YOU
Granulosa cell (GC)- and Oocyte specific Androgen Receptor knockout female mouse
ARAMHRII / GDF9 promoter
AMHRII / GDF9 promoter
AR
promoter
AR
AR
Androgen-Induced Increase in FSHR Protein Levels is Likely Mediated Through
Non-Genomic Actions
M DHT ActD CHX
DHT
FSHR
GAPDH
Sen et.al., unpublished
Med
iaDH
TFlu
tam
ide
U0126
PXNsiR
NA
DHT
PXNsiR
NA +
WT
PXN R
escu
e
Androgens Through Extranuclear ActionsInduce FSHR Protein levels
FSHR
GAPDH
PABPAAAAAA
eIF
5’ Cap
PABP
Src
EG
FR
ARMMP
EGF
Raf
MEK
ERK
PaxillinP-Y
PaxillinP-SP-Y
PaxillinP-SP-Y
PABPPaxillin
TSC1TSC2
mTOR-C1
S6KP
4EBP1P
Tran
slat
ion
Translationinitiation