Placental lactogen also known as human chorionic somatomammotrophin hormone produced during pragnancy.I t stimulate glucose production

1. University of Chakwal
Pakistan

2. Presented by: Aiman
Roll no# UOC-BSZOL-F2020/016
Department of Zoology
Session: 2020-2024
Subject: Endocrinology
Instructor Name: Dr. Syeda Nadia Ahmad
Topic: Placental Lactogen Hormone

3. PLACENTAL LACTOGEN
HORMONE
(A vital player in pregnancy)

4. Introduction:
Placental lactogen(PL) also known as human
chorionic somatomammotrophin, is a
hormone produced during pregnancy
Origin:
Syncytiotrophoblast cells of the placenta
Structure:
Similar to GH & prolactin
Single chain Polypeptide
(191 amino acids)
(Handwerger & Freemark, 2000)
Figure:1.Crystalline structure
of placental
lactogen(https://en.m.wikipedia.o
rg/wiki/File:1Z7C.pdb.png)

5. Regulation of synthesis and secretion:
Synthesize by syncytiotrophoblast cells
Detected at 6th week of gestation
Peak conc. at 30thweek (5-7ug/ml)
1g/day near term
Positively correlated with placental mass
Minute amount enter in fetal circulation
(Sibiak et al., 2020)
Figure:2.PLlevel during pregnancy
https://images.app.goo.gl/nWTxW17q7hB
2f3g69

6. Regulation of synthesis and secretion:
• Specific hormonal & metabolic
regulatory factors are unknown
• Prolonged fasting &hyperglycemia
decrease PL secretion
• Epidermal growth factor increase hPL
release
(Handwerger & Freemark, 2000) Figure.3:syncytiotrophoblast
cells of placenta secrete PL
https://images.app.goo.gl/Yz2t7i4f
d1apMNvf9

7. In Mother In Fetus
Functions

8. ACTIONS IN
MOTHER
Insulin
resistance
Lipolysis
β-cell
proliferation
Breast
development
Metabolic
changes
Enhance
insulin
secretion

9. ➢ Role in
Pancreatic Beta
Cells:
Promotes β-cell
proliferation
Inhibit apoptotic
activity
Protect against
glucolipotoxicity

10. Figure.4:Mechanisms of the biological activity of
placental lactogen (PL) in pancreatic β-cells.
https://images.app.goo.gl/BTeKW1WF4ccJf4ay9
Mechanism
PL bind with PRL
receptors and stimulate
intracellular pathway
inhibit apoptotic activity
by phosphorylation of
protein kinase B
increase expression of
BCL-XL
(Sibiak et al., 2020)

11. Actions in fetus:
Nutrient supply
Promote fetal growth
Organogenesis
Enhance IGF production
Increase glycogen synthesis
Inhibit glycogenolysis
(Handwerger & Freemark, 2000)

12. PL role in early organogenesis:
9.5 day rat embryo were cultured in vitro in the presence&
absence of PL for 48 h by karabulut et al
Embryos treated with PL show improved parameters:
morphological score
 yolk sac diameter
 crown-rump length
somite number
Embryonic & yolk sac protein content
(KARABULUT et al., 2002).

13. PL as a Gestational Marker of Fetal Development:
Higher PL levels
result in better fetal
growth
PL stimulates IGF
production and plays
a role in the
regulation of fetal
growth
(Sibiak et al., 2020)
Figure .5:The influence of increased blood PL levels
on tissues of the developing fetus.
https://images.app.goo.gl/558hcToe2K9zi

14. Metabolic actions of PL in mother & fetus during
gestation:
Figure.6:Metabolic effect of PL.https://images.app.goo.gl/rjaBCXiXCc5V6BvB7

15. Figure.8:conditions
associatedwith
differentlevel of
PL.Created with
BioRender
https://images.app.goo.gl
/F6LYivUVh3ow7dZ27
The summary of clinical conditions associated with elevated
and decreased placental lactogen blood level:

16. How PL cause gestational diabetes?
PL stimulate glucose
production
PL cause insulin
resistance due to which
blood glucose level
increase that leads to
gestational diabetes
(Sibiak et al., 2020).

Figure.7:Higher PLlevel leads to gestational
diabetes
https://images.app.goo.gl/jhxVnznmp1BCiqgRA

17. Macrosomia
Low glucose level
Respiratory
distress
Premature birth
Cesarean delivery
Type 2 diabetes
after delivery
On the
baby:
Risk and effects of gestational diabetes :
On the
Mother:

18. How to deal with gestational diabetes :
Eat right carbohydrates
Eat healthy breakfast
Take prescribed medicine
Monitor blood sugar level
opt for sugar free diet
Sleep well
Avoid sugary drinks and
desserts Figure.8:How to deal with gestational diabetes.
https://images.app.goo.gl/TKcVNaEsju74EzMP6

19. How placental lactogen cause fetal Macrosomia:
PL cause insulin
resistance that leads
to high blood
glucose level in
mother
Transport extra
glucose to fetus
Cause baby to put
on extra weight Figure. 9:fetal macrosomia
https://images.app.goo.gl/L7oH
1P77Px9r5a5K9

20. Conclusions:
In summary, current evidence strongly suggests that
Placental Lactogen is a multifunctional hormone crucial
for fetal growth and maternal adaptations.
PL ensure the optimal supply of nutrients to the fetus and
utilization of the nutrients by fetal tissues.
(Sibiak et al., 2020).

21. References:
• Handwerger, S., & Freemark, M. (2000). The roles of placental growth hormone and placental
lactogen in the regulation of human fetal growth and development. Journal of Pediatric
Endocrinology and Metabolism, 13(4), 343-356.
• KARABULUT, A. K., Layfield, R., & Pratten, M. K. (2002). Growth promoting effects of
human placental lactogen during early organogenesis: a link to insulin-like growth factors. The
Journal of Anatomy, 198(6), 651-662.
• Sibiak, R., Jankowski, M., Gutaj, P., Mozdziak, P., Kempisty, B., & Wender-Ożegowska, E.
(2020). Placental lactogen as a marker of maternal obesity, diabetes, and fetal growth
abnormalities: current knowledge and clinical perspectives. Journal of Clinical Medicine, 9(4),
1142.