BBC2-K34 Biosintesis Hormon

8/11/2019 BBC2-K34 Biosintesis Hormon

1/23

HORMONE SYNTHESIS,RELEASE AND TRANSPORT


2/23

Hormone:

produced in small amounts by specific

tissues (endocrine glands), control the

metabolic and biological activities in thetarget cells

Hormone


3/23

HORMONE CLASSIFICATION

Protein and polypeptide

Amine Steroid

Eicosanoid


4/23

BIOCHEMISTRYMEDICAL FACULTY USU


5/23

PEPTIDE HORMONES

Consist of specific amino acids

Synthesized as large precursor proteins

Stored in membrane-enclosed

compartments

Hydrophillic


6/23

PEPTIDA INSULIN

Di sintesa di Pulau Pankreas sebagaipreproinsulin

Untuk sekresi disimpan di RES oleh enzim mikrosomal dibelah menjadiproinsulin sewaktu memasuki membran RES

Proinsulin diangkut ke golgi kompleksdikemas menjadi secretory granules

Di granula, C-Peptida dipisahkan insulindisekresikan


7/23

Protein and Polypeptide Hormones Synthesis

: Peptide hormone synthesis and packaging


8/23

Proinsulin

Insulin


9/23

AMINE HORMONES

Derived from the amino acid tyrosine

Includes thyroid hormones and

catecholamines

Stored until secreted


10/23

Thyroid gland produce T3 and T4

hormones Iodide (I-) actively transported into the

follicle of thyroid gland

Oxidized to iodine (Io

) by a peroxidase

Thyroid Hormones


11/23

Iodine attached to tyrosine within

thyroglobulin chain

MIT, DIT

MIT and DIT or 2 DIT molecules

coupled together

TSH via cAMP stimulates hydrolyze T3

and T4 from thyroglobulin (inhibited by

KI)

Thyroid Hormones


12/23

STEROID HORMONES

Precursor: Cholesterol

Lipophillic

Immediately released from the cell

following synthesis


13/23

Hormon Steroid

Korteks adrenal sintesis :

glukokortikoid, mineralokortikoid, sexsteroid

Terutama dari kolesterol plasma(sebahagian kecil dari asetil koA)

Kolesterol plasma dirubah menjadi

pregnenolon oleh enzim sitokrom P450(mitkondria atau RES)


14/23

Hormon Steroid


15/23

Hormon Steroid

Kekhususan seluler :

sintesis mineralokortikoid pada sel

glomerulosa18 hidroksilase dan 18 hidroksisteroid

dehidrogenase hanya ditemukan pada

sel ini


16/23

Golongan Hormon Steroid


17/23

Protein Transport

Thyroid Hormones

Globulin alfa (85%)TBG

TBPA (transferitin)

Albumin sedikit


18/23

Protein Transport

Hormon Steroid

Kortisol- 75 % terikat CBG (transkortin)

- 10 % kortisol bebas

- selebihnya pada albumin(mis deksametason)


19/23

Protein Transport

Hormon Steroid

Androgen

- DHEA terikat lemah pada albumin

- Testoteron terikat pada globulin spesifik( SHBG)

Mineralokortikoid- tidak punya protein pengangkut spesifik

- membentuk ikatan lemah dengan

abumin


20/23

EICOSANOIDS HORMONE

Produced from arachidonic acid,

Released from phospholipids by action of

phospholipase A2,phospholipase C

Produced in almost every organ

In one pathway arachidonic acid is converted

to prostanoids by a group of enzymes, thecyclooxygenase system

A second pathway to produce leukotrienes

by the enzyme 5 lipoxygenase


21/23

EICOSANOIDS HORMONE


22/23

Prostaglandins

SAIDS inhibit action of phospholipase

NSAIDs, such as aspirin and derivatives of

ibuprofen, inhibit cyclooxygenase activity ofPGH2 Synthase

They inhibit formation of prostaglandinsinvolved in fever, pain, & inflammation

They inhibit blood clotting by blockingthromboxane formation in blood platelets


23/23

REFERENCES

Devlin T M, PhD. Text Book of Biochemistry withClinical Correlations 5thed. Wiley-Liss, New York.2002 : 906-952, 982-983

McKee Trudy, McKee James R. The molecular

basis of Life. 3rded. McGraw-Hill. Americas, NewYork. 2003 : 541-559

Murray R K, et al. Harpers Biochemistry 26thed.Appleton & Lange. America 2003: 434-473

Raff A, et al. Moleculer Biology of The Cell. 4thed.Garland Science. New York. 2002: 832-892

Stryer L. Biokimia. Edisi 4. EGC, Jakarta. 2000.:340-358

BBC2-K34 Biosintesis Hormon

Documents

Transcript of BBC2-K34 Biosintesis Hormon