carbohydrate metabolism

Presented by,Soundarya VIII BDS

PATHOPHYSIOLOGY OF CARBOHYDRATE

METABOLISM

1) Textbook of Oral Pathology – Shafer's2) Textbook of biochemistry – Satyanarayana3) Textbook of general physiology –

Sembulingam4) Textbook of general pathology – Harsh

Mohan5) www.wikipedia.org

REFERENCES

GLYCOGEN STORAGE DISEASE

TYPE NAME ENZYME DEFECT ORGAN(s) INVOLVED

CHARACTERISTIC FEATURES

1 VON GIERKE’SDISEASE(TYPE 1 glycogenosis)

GLUCOSE 6-PHOSPHATESE

LIVER,KIDNEY,INTESTINE

GLYCOGEN ACCUMULATES IN HEPATOCYTES AND RENAL CELLS,ENLARGED LIVER AND KIDNEY,FASTING HYPOGLYCEMIA,LACTIC ACIDEMIA,HYPERLIPIDEMIA,KETOSIS,ARTHRITIS.

2 POMP’Sdisease

LYSOSOMAL alpha-1,4glyosidase(acid maltase)

All organs Glycogen accumulation in lysosomes in almost all the tissues, heart is mostly involved, enlarged liver and heart, nervous system is also affected, death can occurs at an early age due to heart failure.

3 Corie’s disease Amylo alpha-1,6-glucosidase

Liver, muscle,heart,leucocytes

Branched chain glycogen accumulates, liver enlarged, clinical manifestation are similar but milder compared to von gierke’s disease.

type NAME ENZYME DEFECT ORGAN(S) INVOLVE

CHARACTERISTIC FEATURES

4 ADESON’S DISEASES

Glucosyl 4-6 transferase

Most tissue Rare disease, glycogen with only few branches accumulate, cirrhosis of liver, impairment in liver function

5 McArdle’s DISEASE(type V glycogenosis)

Muscle glycogen phosphorylase

Skeletal muscle Muscle glycogen storage is very high, not available during exercise, muscle cramps, blood lactase and pyruvate do not increase after exercise, muscle may damage due to inadequate energy supply.

6 HER’S DISEASE Liver glycogen phosphorylase

liver Liver enlarged, liver glycogen can not form glucose, mild hypoglycemia and ketosis seen.

7 TARUI’S DISEASES

phosphofructokinase

Skeletal muscle,erythrocytes

Muscle cramps due to exercise, blood lactase not elevated ,hemolysis occurs.

Von Gierke’s disease

Von Gierke’s disease

Pompe’s Disease

Pompe’s disease

• Mucopolysaccharidoses results from the abnormal degradation of glycosaminoglycans such as dermatan sulfate, keratin sulfate resulting in organ accumulation and evental dysfuntion

Glycosaminoglycan are present normally as a component of cornea, cartilage, bone, connective tissues & RE system

Disturbances in carbohydrate metabolism

1. Mucopolysaccharidoses (MPS)

Cause: deficiency of the catabolic enzymes required for the breakdown of glycosaminoglycan.

10 known enzyme deficiencies cause 6 distinct types of MPS

Transmission by autosomal recessive except for MPS type 2 which is X- linked.

MPS are progressive disorders characterized by involvement of multiple organ including brain , liver ,spleen , heart and blood vessel

Many are associated with coarse facial features , clouding of cornea and mental retardation

• 6 types of MPS Type 1 Hurler Syndrome, Hurler-Scheme

syndrome and Scheme syndrome.

Clinical Features

HURLER SYNDROME• It is a disturbance of mucopolysaccharide

metabolism

• Characterized by an elevated mucopolysaccharide excretion level in the urine

CLINICAL FEATURESProgressive corneal clouding is the classic manifestation of the disease as is hepatosplenomegali results in protuberant abdomen Head appears large Prominent forehead Broad saddle nose with wide nostrils Puffy eyelids with coarse bushy eyebrows Thick lips, large tongue, open mouth nasal congestion with noisy breathing

RAL MANIFESTAoooooooooooooTooijihION Consist of shortening and broadening of

mandible with prominent gonions Localized area of bone destruction in the jaw

which appear hyperplastic dental follicles with large pool of metachromatic material i.e muco polysaccharide

Teeth are small, wide space between two teeth Gingival hyperplasia

Histologic features• Excessive accumulation of intracellular

mucopolysaccharide in tissue and organs like liver, spleen, reticuloendothelial system, nervous system, cartilage , bone and heart.• Abnormal deposition are also found in fibroblast

appear as “clear” or “Gargoyle” cells.• Hurler cells are identified with Toluidine blue or

Alcian blue\Aldehyde fuschin stain.

Laboratory findings• Elevated level of mucopolysaccharides in

urine.• Metachromatic granules or Reilly bodies can

be seen in cytoplasm of circulating lymphocytes.

• Treatmen- no treatment for this disease.

THANK YOU