LH hormone.pdf

LH is a heterodimeric glycoprotein
• One alpha and one beta subunit make
the full functional protein
• During the reproductive years, typical
levels of LH are between 1-20 IU/L

1. University of Chakwal,Pakistan

2. Topic:Upregulationand downregulation
of Luteinizing hormone
Department of Zoology
Presented by: Alishba Qirat
Roll# 20M-UOC/ZOL-25
BS Zoology
Session: 2020-2024
Subject: Endocrinology
Instructor Name: Dr.SyedaNadia Ahmad

3. •Introduction
•Originofproduction
•Function
•Upregulation
•Downregulation
•Treatment

4. Luteinizing hormone(LH)
•LHisaheterodimericglycoprotein
•Onealphaandonebetasubunitmake
thefullfunctionalprotein
•Duringthereproductiveyears,typical
levelsofLHarebetween1-20IU/L
•Inmalesover18yearsof
age,referencerangeshavebeen
estimatedtobe1.8-8.6IU/L
(Rodolfo,2018).
Fig 1.1: Structure of LH
https://commons.wikimedia.org/
wiki/File:LH-4_structure.svg

5. Origin of production
•LuteinizingHormone(LH) is
producedinthepituitarygland
undertheregulationofthe
Gonadotrophicreleasinghormone
(GnRH).
•Itisthenreleasedintotheblood
streamtowardsthetargettissues.
•LHlevelsarenormallylowduring
childhoodandinwomen,highafter
menopause(Holesh,2022).
Fig.1.2 : HPG Axis
https://www.sciencedirect.com/topics/
neuroscience/hypothalamic-pituitary-
gonadal-axis

6. Functionsof Luteinizing Hormone
•In Women
•Targetorgans:Ovaries
•Stimulateconversionof
ovarianfollicletoCorpus
Luteum
•ActsonCorpusLuteumto
stimulateestrogenand
progesteroneproduction
(Holesh,2022).
•In Men
•Target organs:Testis
•Predominant regulator of
testicular steroidogenesis
•Acts on leydigcells to stimulate
the production of testicular
androgens (Holesh,2022).

7. On day 14 there is a burst of LH that
triggers ovulation

8. Normal LH Levels
LUTEINIZING HORMONE NORMALRANGES
InChildhood 0.5-1.9 IU/L
InAdults 1.8-8.6 IU/L
In follicular phase 1-18 IU/L
In luteal phase 0.5-18 IU/L
Post menopause 12-55 IU/L

10. UPREGULATION
OFLH
HighLHlevelscansignify
thatsexorgansaren’t
producingenoughsteroid
hormonesneededfora
reproductiveprocessto
takeplace.Thisistypical
ofwhentheovariesand
testeshaveexhaustedtheir
abilitytoproduceestrogen
andtestosterone,from
genetic,autoimmune,
surgical,orphysiologic
causes.

11. Elevated LH Levels
Thyroid Diseases
and Adrenal gland
Disorders

12. High levels of LH in a woman’s blood can be a sign of
“primary ovarian failure,”
It can happen because of
•Metabolicdisorder
•Geneticdisorder
•Autoimmunedisorderorhavealownumberoffollicles,
thetinysacsinovaries
•Inmale,abnormallyhighLHlevelscanbeasignof
primarytesticularfailureGonethroughchemotherapyor
radiationtherapy(Gaskinsetal.,2021).

13. DOWNREGULATION
OF LH
Low LH levels can
signify that pituitary
gland isn’t making the
LH needed to spur
changes in your body
that support sexual
development,repro-
duction.

14. •LowlevelsofLHmaybeasignof“secondaryovarian
failure,”whichmeanstheproblemstartswiththepituitary
glandorhypothalamus.
•LowLHlevelsarelinkedtolatepuberty,andhighlevelsare
linkedtoearlypuberty.
•LHdeficiencycanbecongenitaloracquiredbutbasedon
HPGaxis.
•CausesofLHdeficiencycansubdividedintohypothalmic
andpituitarycauses(Gaskinsetal,2021).

15. Hypothalamic Causes
1.KallmannSyndrome
•CongenitalcauseofLHdeficiency
•DecreasedproductionofGnRHhormone
•Reducedproductionofsexhormones
•Asaresultabsenceofpubertyandsecondarysexual
characteristics
2.LHbeta-subunitmutations
•MutationsinbetasubunitofLH

16. 3.IdiopathicHypogonadotropichypogonadism
•CompleteorpartialabsenceofGnRH-inducedreleaseof
LH.
4.Stressrelatedhypogonadotropichypogonadism
•Duetohypothalamicsuppression
•Byprolongedstrenuousphysicalexerciseandextreme
weightloss.
•CauseelevationinCRHwhichinhibitGnRHrelease
(kalantaridouetal.,2004).

17. Pituitary Causes
1. Hyperprolactinemia
•High level of prolactin inhibits the secretion of LH from
anterior pituitary.
•Result in hypogonadism,infertility.
2. Sheehan syndrome
•Caused by massive haemorrhageduring childbirth.
•Causes ischemic infarction of pituitary gland (kalantaridou
et al.,2004).

18. Epidemiology
•Hypogonadotropichypogonadismis between 1 to 10000 in
men and women.
•Almost 66% of cases are associated with kalmannsyndrome
,more common in men.
•Stress-related HH is common in young women and accounts
for 30% cases.
•About 52% of women suffering from PCOs and 30% of
them are unaware (Samperiet al.,2022).

19. •Measuring the level of
luteinizing hormone.
•To evaluate fertility issues.
•Working of reprodutiveorans
of male and female.
•Diagnose puberty in children.
•To diagnose pituitary functions.

20. Treatment
•TreatmentwilleithertargetLHlevelsdirectlyormake
upforthelackofLHbytargettingotherProcesses
•Withexerciseandlowglycaemicnutrition.
•Inadditionantioxidanthavebeenshowneffectivein
reducingtheLHlevels.
•WomenwithLHdeficiencyshouldreceiveestrogen
replacementTherapyorhormonereplacementtherapy
(Wortmannetal.,2019)

21. References
•HoleshJE,BassAN,LordM,StatPearlsPublishing;
TreasureIsland(FL):May8,2022.Physiology,Ovulation.
•GaskinsAJ,MumfordSL,Wactawski-WendeJ,
SchistermanEF.Luteinizinghormonelevelsinreproductive-
agedwomen.EurJNutr;51(2):249-253.Accessed
1/08/2021.