Presentation is loading. Please wait.

Presentation is loading. Please wait.

بسم الله الرحمن الرحيم.

Similar presentations

Presentation on theme: "بسم الله الرحمن الرحيم."— Presentation transcript:

1 بسم الله الرحمن الرحيم

2 Glycolipids By Amr S. Moustafa, M.D.; Ph.D.

3 Outlines Overview and Functions Structure and Types
Synthesis and Degradation Sphingolipidosis

4 Overview Essential component of membranes Abundant in nervous tissue
Extra-nervous tissue: e.g., Receptors for Cholera toxins Diphtheria toxins Viruses

5 Overview Regulation of growth & development Very antigenic:
CONT’D Regulation of growth & development Very antigenic: Blood group antigen Embryonic antigen Tumor antigen Cell transformation

6 Sphingolipids: Structure and Types
Ceramide = Sphingosine + fatty acid Sphingomyelin = Ceramide + Phosphorylcholine Cerebrosides = Ceramide + Monosaccharides Globoosides = Ceramide + Oligosaccharides Gangliosides = Ceramide oligosaccharides + NANA

7 Neutral Glycosphingolipids
Cerebrosides = Ceramide monosaccharides Galactocerbrosides = Ceramide + Galactose Glucocerbrosides = Ceramide + Glucose Globosides = Ceramide Oilgosaccharides Lactosylceramide = Cer-Glc-Gal Forssman antigen = Cer-Glc-(Gal)2-(GalNac)2

8 Galactocerbroside

9 Acidic Glycosphingolipids
Negatively charged at physiological pH Gangliosides: Most complex Ganglion cells Ceramide oligosaccharides + NANA 2. Sulfatides: Nerve tissue and kidneys Cerbrosides + Sulfated Gal

10 Gangliosides GM2

11 Sulfate donor: PAPS

12 Sulfatides Galactocerbroside 3-sulfate

13 Sphingolipids’ Synthesis

14 Sphingolipids’ Degradation
Lysosomal hydrolytic enzymes Last on, First off Defective: Total or partial Sphingolipidosis

15 Sphingolipidosis Synthesis (Normal); Degradation (Defective)
Substrate accumulates in organs Progressive, early death Phenotypic and genotypic variability Autosomal recessive, Except Fabry (X-linked) Rare, Except Ashkenazi Jewish

16 Sphingolipidosis Diagnosis: Treatment: CONT’D Measure enzyme activity
Cultured fibroblasts or peripheral leukocytes Cultured amniocytes (prenatal) Histologic examination DNA analysis Treatment: Replacement Therapy: Recombinant human enzyme Bone marrow transplantation: Gaucher disease

17 CONT’D Sphingolipidosis

18 Niemann - Pick Disease

19 Gaucher Disease

20 Prostaglandins Eicosanoids (20 C): Prostaglandins (PG)
Thromboxanes (TX) Leukotrienes (LT) PG Vs Hormones: All cells Local acting & Not stored Short half-life Plasma membrane & nuclear receptors

21 Prostaglandin’S Synthesis
Dietary precursor: Linoleic acid 18:2 (9, 12) Immediate precursor: Arachidonic acid 20:4 (5, 8,11,14) Prostaglandin endoperoxide synthase: Microsomal enzyme Two Catalytic activities: Fatty acid cyclooxygenase (COX), 2 O2 Peroxidase (GSH) Parent Prostaglandin : PGH2

22 Prostaglandin’S Synthesis

23 COX Isoenzymes COX-1: Constitutive Most tissues Important for:
Integrity of gastric mucosa Renal homeostasis Platelet aggregation

24 COX Isoenzymes CONT’D COX-2 Inducible Limited No. of tissues Stimulus:
Products of inflammatory & immune cells Mediates: Inflammatory response: Pain, Redness & Swelling Fever of infection

25 COX Inhibitors Cortisol (Steroid): Selective COX-2 (-)
Phospholipase A2 (-) NSAIDS: Both COX-1 and –2 (-) Side effects: Gastric, Renal & Clotting Low-dose Asprin therapy Celecoxib: Selective COX-2 (-)

26 Prostaglandin’S Functions

Download ppt "بسم الله الرحمن الرحيم."

Similar presentations

Ads by Google