CARBOHYDRATE CHEMISTRY:-

High yield Medical biochemistry - NEET,PG & FMGE Dr.G.Bhanuprakash

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CARBOHYDRATE CHEMISTRY:-

Formula:- Cn (H2O)n Glucose and mannose are epimers at C2 carbon

Glucose galactose epimers at C4

Enantimomers are mirror images to each other.

α and β cyclic forms of D-glucose known as anomers

C1 is anomeric carbon

Benedict test reducing properties of sugars

Sodium amalgam is used as reducing agent.

Reduction of mono saccharides gives alcohols.

Aldose reductase converts aldehydes to alcohols.

Fructose is converted to sorbitol dehydrogenase (liver)

Monosaccharides gives needle shaped osazones.

Maltose gives sunflower shaped osazones

Lactose gives powderpuff shaped osazones

Maltose (α1-4) (glucose + glucose) – maltose (hydrolysed)

Lactose (βgalactose – βglucose) (β1-4) – lactase (hydrolysed)

Sucrose (glucose-fructose) (α1- β2)

Glucosidic bond- bond between monosaccharides.

Sucrose is hydrolysed by sucrase/invertase

Dextrins are breakdown product of starch

Inulin is a polymer of fructose

Glycogen and starch are polymer of glucose

Inulin is need to assess GFR

Dietary fiber is cellulose (β-glycoside bond)

D-glucoronic acid + N-acetyl glucosamine – Hyaluronic acid

Keratin sulphate keeps cornea transparent

LIPID CHEMISTRY:-

Saturated fatty acids does not contain double bond

Unsaturated fatty acids has double bonds

Linolecic, linolenic and arachidonic acid (PUFA)

Deficiency of EFA – phyrnoderma (toad skin)

Arachidonic acid gives Eicasonoids

Unsaturated fatty acids exists in Cis form

Hydrolysis of triacyl glycerin with alkali produces soaps (saponification)

Vit.E is naturally occuring antioxidant, superoxide dismutase, urase


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Purity of fatty acid is checked by iodine number

RM number (Reichert-Meissl) – to check purity of butter

Phospholipids – free fatty acids + alcohol + phosphate + nitrogen Base

Lecithin – choline ( nitrogen base) - ( lung surfactant)

Hormones like oxytocin and vasopressin action is mediated by phosphatidyl inositol

Sphinogophospholipid :- cerebonic acid + sphingosine + phosphate + choline =

sphingomyelin.

Phospholipases – A1, A2, C, D

PLA2 (phospholipase A2)– give arachidonic acid

Ganglioside GM2 accmulates in taysachs disease

Cholesterol –C27 H46 O

Cholesterol has ohg group at C3. Double bond between C5-C6

Ergosterol is precussor for vit.D

Zaks test is used to identify the qualitative analysis of cholesterol

Emulsified fats in the intestine forms Micelles

PROTEINS AND AMINO ACID CHEMISTRY:-

kjeldahi’s method is used to find out protein in biological fluids.

the amino acid glycine has H as side chain

alanine has –CH3 (methyl) as side chain.

Cysteine and methionine are sulphur containing aminoacid.

Aspartic acid and glutamic acid are acidic aminoacid

Phenyl alanine, tyrosine, tryptophan –aromatic aminoacid

Alanine is glucogenic aminoacid.

Leucine and lysine – ketogenic aminoacid.

Monosodium glutamate intolerance causes chinese restaurant syndrome

D-penicilamine- used as chelating agent in Wilson’s disease (Accmulation of copper in

brain)

N-acetyl cysteine used in cystic fibrosis and chronic renal failure.

GABA-pentane is used as anticonvulsant

Linear sequence of aminoacid seen in primary structure

α helix and β sheath – secondary structure.3 diminsional arrangement of protein –teritary

2 or more poly peptide chains- quartenary structure

Peptide bond – bond between 2 aminoacid.

Sangers reagent – used to determine aminoacid sequence

Sangers reagent used to determin insulin structure

Biurate is a compound formed by heating urea to 180 degrees . process is biurate reaction

Copper sulphate is used for heatin in biurate reaction


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Glutathione is involved in transport of amino acfid in intestine and kidney via glutanyl

cycle/meister cycle.

Aspertame – artifical sweetner.

NUCLEIC ACIDS AND NUCLEOTIDES:-

Nucleotides – nitrogen base + pentose sugar + phosphate

Nucleoside – nitrogen base + sugar

Ribose and deoxyribose differs in C2

Purine nucleotide is Adenosin mono phosphate

Pyramide nucleotide is Cyitidine MonoPhosphate, UradineMonoPhosphate

Alopurinol used in the treatment of gout

5- fluorouracil used in the treatment of cancers

Azathioprine is used to suppress immunological rejection during transplantation

The width of double helix of DNA – 20 Å / 2 nm

Each turn of helix contains 10 base pairs

Each turn of helix is 34 Å

2 strands of double helixd are hold by H-bonds

DNA protiens are known as histones

B-DNA proposed by watson and crick in 1953

A-DNA has 11 base pairs per turn.

A and B- DNA are right handed helix

Z-DNA is left handed helix

Z-DNA has 12 base pairs per turn (zigzag)

Formamide destahilses H-bonds, therefore it lowers Tm

Formamide used in recombinant DNA technology

The sugar in RNA kis ribose

RNA is subjected to alkali hydrolysis and DNA cannot

RNA can be identified lby orcinol colour reaction because of ribose

Nucleolus synthesis r-RNA

DNA converts M-RNA converts protein

M-RNA has 7 methyl guicnosine at 5 prime end

The 3 prime kend contains poly- A tail (MRNA)

The stucture of t-RNA resembles clover leaf

the acceptor arm of t-RNA has CCA cap (3prime)

D-arm has dihyrouridine (t-RNA)

TψC arm has T, pseudouridine and C (tRNA)

http://en.wikipedia.org/wiki/%C3%85

http://en.wikipedia.org/wiki/%C3%85


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ENZYMES :-

There are 6 cclasses of enzymes

The functional unit of enzyme is holoenzyme

Holoenzyme is made up of apoenzyme (protein part) and co-enzyme (non-protein part).

Increase in concentration of substrate increase enzyme velocity

Km = ½ Vmax

Km = S (substrate concentration) Km-(michaelis-menten constant)

Km is defined as the substrate concentration to produce ½ maximum velocity.

Low Km denotes strong affinity between enzyme and substrate

When enzymes are exposed to C and above temperatures denaturation occurs.

All enzymes are active at neutral PH (7)

The most common aminoacid at active site is serine

INHIBITORS:-

Xanthine oxidase – allopurinol

MAO (mono amino oxidase) – ephedrine, auphetamine

Dihydrofolate reducatse – aminopterin, amethopterin, methotrexate

Acetylcholine esterase – succinyl choline

Dihydropteroate synthase – sulfanilamide

Vit. Kepoxide reductase – dicumorol

HMG co-A reducatse – lorastatin, compactin.

Disulfiran is the drug used in the treatment of alcoholism

Transketolase requires TPP

Streptokinase is used to remove blood clots

Streptokinase converts plasminogen to plasmin

Asperginase is used in treatment of leukemias

Increase amylase – acute pancreatitis

Increase SGPT (serum glutamate pyruvate transaminase) – liver diseases

Increase alkaline phosphatase – rickets and bone diseases

Increase acid phosphatase – prostate carcinoma

Increase aldolase – muscle dystrophy

Increase troponin I – MI (first marker)

Increase CPK1 – BB (brain)

Increase CPK2 – MB (heart)

Increase CPK3 – MM (skeletal muscle)


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LIPID METABOLISM:-

TG – plasma concentration is 75-150 mg/dl

Cholesterol – plasma concentration is 150-200 mg/dl

Hypercholesteremia - >250mg/dl

Hormone sensitive TG lipase removes fatty acid from C1 or C3 of TAG

glucagon, epinephrine, thyroxine, ACTH – increase cAMP – increase lipolysis.

Insulin – decrease cAMP – decrease lipolysis

Glycerol is metabolized by liver.

FFA from Adipose Tissue are transported to liver by albumin.

Brain, erythrocytes cannot utilize FA

FA activation – cytosol (ATP, Co-A, mg2+) requires 2 ATP

Long chain FA are metabolized in peroxisomes

Tangair’s disease – plasma HDL particles are almost absent

Biosynthesis of FA in liver starts with glycerol and in adipose tissue with glucose and

acetyl Co-A

Glycolipids act as receptors in cell membrane

Absorption of cholesterol from intestine is by diffusion

Cholesterol gives bile salts, vit.D, steroid hormones (sex hormone and corticoids)

Prostaglandin exhibit platelet aggregation, increase cAMP and vasodilation

Obesity gene – leptin

β-oxidation – mitochondria

activation of FA in β-oxidation – cytosol

melanoyl Co-A inhibits – CAT-I, thus inhibits β-oxidation

CAT-I – outer mitochondrial membrane

CAT-II – inner mitochondrial membrane

Medium chain aceyl Co-A dehydrogenase, rate limiting step of β-oxidation.

β-oxidation of palmitate gives 106 ATP

SIDS (sudden infant dead syndrome) – deficiency of medium chain aceyl Co-A

dehydrogenase (M-CAD.)

Methyl melanoic academia – vit.B12 deficiency

Methyl melanoic Co-A – requires Vit. B12

Zellweger syndrome – absence of peroxisomes cerebrohepatorenal syndrome.

Zellweger syndrome – defect in long chain fatty breakdown

α-oxidation – Refsums disease – accumulation of phytanic acid.

ω-oxidation requires – cytochrome P450 , NADPH, O2.

Ketone bodies are synthesized in liver

Ketone bodies are utilized by brain in prolonged starvation

HMG – CoA synthase – rate limiting step in ketone bodies synthesis

Ketone bodies cannot be utilized by liver because of deficiency of thiophorase

Acetone exhaled by lungs – sweetish odur.


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Detection of ketone bodies in urine – rothers test

Glucagon stimulates ketone bodies synthesis, insulin inhibits

Treatment of keto acidosis – insulin

Fatty acid bio-synthesis – cytosol.

Acetyl Co-A for fatty acid biosynthesis (FAB) obtains from citrate lyase

NADPH in FAB obtained form HMP- pathway and malic enzyme

Acetyl Co-A carboxylase – rate limiting step in FAB

Insulin stimulates FAB –glucagon inhibits

Un-saturated fatty acids synthesized by fatty aceyl Co-A desaturase. Human lacks this

enzyme.

TAG synthesis – adipose tissue

Cerebronic acid + phyngosine = seramide

Seramide + phosphate + choline = sphingomyelin

Phospholipase A1 – cleaves FFA at C1

Phospholipase A2 – cleavesFFA at C2

Phospholipase C - cleaves phosphate and glycerol found in lysozomes of hepatocytes

L-CAT found in lungs

L-CAT activity is associated with apo-A1 of HDL

Sphingomyelinase deficiency niemann’s pick’s desease

Deficiency of seramidase Fauber’s disease

Deficiency of β-galactidase krabbe’s disease

Deficiency of β-glucosidase gauchers disease

Deficiency of α-galactidase fabrys disease

Deficiency of hexosaminidase A – Taysachs disease

Cholesterol biosynthesis, liver- 50%, intestine- 15%

Cholesterol synthesis- cytosol.

HMG- CoA reductase – rate limiting step in cholesterol biosynthesis

Cholesterol formulae :- C27 H46 O

Glucagon – glucocorticoids – decrease cholesterol biosynthesis

Compactin, lorastatin inhibits – HMG Co-A reductase

HMG-CoA reductase also inhibited by bileacids

7-α-hydroxylase – rate limiting step in bileacid biosynthesis

95% of the bile is reabsorbed and return back to liver

Primary bileacids – cholic acid chenodeoxycholic acid.

Conjuation of bile acids done by – glycine , taurine

Deoxycholic acid,lithocholic acid – secondary bile acids

Chenodiol treat for cholilithiasisctiatn of chylomi

Chylomicrons has B48

VLDL has B100

HDL has apoprotein-A


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Activation of chylomicrons and VLDL requires Apo-CII and Apo-E from HDL

Lipoprotein lipase deficiency – hyperlipoprotenimia type I

Defect in LDL receptors – type IIA

Excess apoB – type IIB

Abnormality in apo-E – type III

Over production of TG – type IV

Defect in HDL receptors – tangier’s disease

OXIDATIVE PHOSPHORYLATION AND ETC:-

Phosphophenol pyruvate is 14.8 cal/mole.

S-adenosyl methionane is 10 cal/mole

cAMP is 12 cal/mole

ATP is 7.3 cal/mole

The inner mitochondrial membrane is impermeable to H+, K+ and Na+

Co-enzyme Q is also known as ubiquione

Complex-I – NADH-co-encyme Q reductase inhibited by – amytal, rotenone,

pricydine-A

Complex III – Co-enzyme Q-cytC reductase inhibited by antimycin A,

BAL (british anti lewisite)

Comple IV – cytochrome oxidase inhibited by cyanide, CO, Na-azide.

otation of -subunit is 12

ATP synthatase has F0 and F1 subunits.

F0 – channel protein C

F1 – central γ subunit, 3α, 3β

Mutation of mitochondrial DNA – oxiphos disease AKA (lebers hereditary optic

neuropathy)

2, A dinitrophenol – uncoupler of oxiphosphorylation

Digomycin inhibits oxidative phosphorylation by binding to ATP synthetase 2 blockes

proton channels

Atractyloside inhibits oxidative phosphorylation by blocking the adequate supply of

ADP.


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VITAMINS:-

Vit.A:-

Retinol is present in animals in the form of retinylester

Retinal,retinol and retinoic acid are vitamers of vitamin A

β- carotene gives l2 moles of retinal by 1 ’-1 ’ di-oxygenase

retinyl esters are transported by chylomicrons and stored in liver

retinol is transported in circulation by RBP 9retinal binding protein)

rods – dim light vision

cones – bright light

vit-A required for rods

rhodopsin present in rods

rhodopsin = 11-cis retinal + opsin

during walds visual cycle rhodipsin is bleached to metarhodopsin-II which increases C-

GMP an degenerates nerve impulse

Vit-A deficiency night blindness

Serene deficiency of vit-A causes xerophthalmia, characterized of dryness of conjunctiva

and cornea, white triangular plaques, bitot’s spots are seen

Xerophthalmia leads to keratomalacia causing total blindness

Vit. D

Ergosterol (plants) ergocalciferol – vit. D2

Cholecalciferol (animals)- vit.D3

Vit-D synthesis takes place in skin.

1,25- Di-hydroxycholecalciferal is known as calcitriol i.e., active form of vit-D

25- α -hydroxylase and 1-α-hydroxylase requires cyt-p-450, NADPH and O2

Vit.D is essential for bone formation

Vit-D deficiency:- pickets – bowlegs – children; osteomalacia – Adults.

Alkaline phosphatase activity elevated in rickets

Vit-D is more toxic in over doses

Vit-D is transported in the circulation by α2-globulin

1-α-hydroxylase present in kidney and stimulated by PTH

25- α –hydroxylase present in liver

Vit-E:-

Anti sterility vitamin

Also known as tocopherols α,β,γ,δ out of these α-tocopherols more active

Vit-E is transported by VLDL and LDL in the circulation

Normal plasma levels of tocopherols <1mg/dl


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Vit-E naturally occurring antioxidant and it requires selenium

Vit-E prevents peroxidation reactions of PUFA

ALA-synthase requires vit.E

Vit-K:-

Vit-K also synthesized by intestinal bacteria

Bile salts are essential for absorption of vit- K

Transported to liver by means of LDL

Vit-K is responsible for post transitional modification of 2,7,9,10 clotting factors by

carboxylation of glutamic acid

Carboxylation of glutamic acid is inhibited by dicumarol

Deficiency of vit-K leads to lack of acive prothrobin in circulation

High doses of vit-K causes hemolytic anemia

Vit-C :-

Vit-C is required for collagen formation

Vit-C is co-enzyme for hydroxylation of proline and lysine, where protocollagen is

converted to collagen

Deficiency of vit-C leads to scurvy, delayed wound healing

Vit-B1 :-

co-enzyme – TPP

TPP required for PDH transketolase

Deficiency seen in the people who consume polished rice as a staple food

Elevation of pyruvate in plasma and excrets in urine

Wet-beriberi – edema – systolic increase – diastolic decrease – bouncing pulse.

Dry-beriberi – no edema – neurological manifestations are seen

Decrease transketoplase activity – Wernick’s korsakoff syndrome

Thyamine deficiency more commonly seen in alcoholics.


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B2 – RIBOFLAVIN:-

Coenzymes – FMN, FAD

Used in oxidation reduction reactions

Deficiency – cheilosis, glosittis, dermatitis

Assessment of glutathione reductase in erythrocytes will be useful in

accessing riboflavin deficiency

NIACIN:-

Coenzyme – NAD, NADP

Pellagra preventive factor

Niacin coenzymes synthesized from tryptophan

Niacin deficiency results pellagra

Pellagra symptoms – diarrhea, dementia, dermatitis – death “HD”

Niacin inhibits lipolysis

Niacin is used in treatment of hyperlipoprotenuria type_IIB. (increased

VLDL, increased LDL)

PYRIDOXINE:- B6

Coenzyme – pyridoxine, pyridoxal pyridoxamine

Pyridoxine used in transamination, decarboxylation, deamination.

Active form is pyridoxal phosphate (PLP) transamination

It is required for the production of the monoamine neurotransmitters

serotonin, dopamine, norepinephrine and epinephrine, as it is the precursor

to pyridoxal phosphate: cofactor for the enzyme aromatic amino acid

decarboxylase. This enzyme is responsible for converting the precursors 5-

hydroxytryptophan (5-HTP) into serotonin and levodopa (L-DOPA) into

dopamine, noradrenaline and adrenaline. As such it has been implicated in

the treatment of depression and anxiety.

DEFICIENCY MANIFESTATIONS:-

1. neurological symptoms

2. excretion of xanthurenic acid in urine

3. drugs isoniazid and penicillamine can cause B6 deficiency.


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BIOTIN – B7

It is required for carboxylation reactions

Eg.:- 1. acetyl CoA carboxylase

2. propony CoA carboxylase

3. pyruvate carboxylase

PANTOTHENIC ACID:-

also known as coenzyme –A

deficiency – burning feet syndrome

FOLIC ACID:-

it is important for one carbon metabolism

the active form if tetrahydrofloate TH4 or THF

the most common vitamin deficiency

important for the synthesis of nitrogenous bases in DNA and RNA.

Supplemented in pregnancy to prevent neural tube defects

Deficiency of folic acid megaloblastic anemia.

In folic acid deficiency FIGLU excreted in urine.

(FIGLU- formiminoglutamate)

VITAMIN –B12 (COBALAMIN)

The absorption of vit-B12 requires intrinsic factor, intrinsic factor

produced by gastric parietal cells

Absorption of B12 into mucosal cells is Ca+2 dependent

In mucosal cells B12 converts to methyl B12

From the mucosal cells transported in the plasma by transcobalamins

i.e., Tc-I and Tc-II

Methyl –B12 (mucosal cells) – 90% binds to Tc-I and 10% binds to

Tc-II

Vit-B12 stores in liver, as deoxyadenosyl

B12 (storage form of vit B12)

DEFICIENCY:-

Methyl melanoic acidemia

Pernicious anemia

Neurological manifestations (optic neuropathy)


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Use schilling test to detect deficiency

Vit-B12 deficiency - most common cause is malabsorption sprue .

HAEMOGLOBIN AND PORPHYRINS:-

METABOLISM:-

Heme contains porphyrin molecule known as protoporphyrin IX

Heme contains 4 pyrole rings

The central atom of heme contains Fe

The adult hemoglobin – α2,β2 – HbA1

Fetal hemoglobin – α2 γ2 – HbF

HbA2 – α2 δ2

Glycosylated hemoglobin – Hb A1 C – α2 β2 –glucose (diabetes)

Fetal Hb has more affinity towards O2 than adult – HbF – 100% ;

HbA1 – 95%.

In heme if Fe2+ oxidizes to form Fe3+ known methehemoglobin

BIOSYNTHESIS OF HEME:-

Heme synthesis take place in liver

ALA synthase is rate limiting step in heme biosynthesis


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HEME METABOLISM :-

Bilirubin bound to albumin to form bilirubin albumin complex


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Enters liver for conjugation

Bilirubin enters into intestine where it reacts with bacterial enzymes to

form stercobilin which enters into feces

1 gm of Hb gives 35 mg of bilirubin

Bilirubin- albumin complex binds to receptor LIGANDIN which in

present on hepatocytes

Porphyrias :-


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CARBOHYDRATE METABOLISM:-

Insulin dependent glucose transport – GLIT-4 skeletal muscle, adipose

tissue

GLUT-1 – erythrocytes

GLYCOLYSIS CYCLE:-


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Location – cytosol of all most all the cells

Glucokinase – liver, hexokinase – other tissues

Hexokinase – low Km, glucokinase- High Km

(PFK-1) Phosphofructokinase-1 – rate limiting step

Spilitting – aldolase-A . 7 ATP in aerobic glycolysis and 2 ATP in

anerobic

Glycolysis in RBC is always anerobic

IRREVERSIBLE STEPS:-

Hexokinase

PFK-1

Pyruvate kinase ( deficiency hemolytic anemia )

INHIBITORS:-

Glycerol dehyde 3 phosphate dehydrogenase – iodo acetate ,arsenate

Enolase – fluoride

Phospphotriose isomerase - bromohydroxy acetone phosphate

End product of aerobic glycolysis – pyruvate

End product of anaerobic glycolysis – lactate

Glycolysis in erythrocytes is always anaerobic

Number of ATP under aerobic glycolysis 7

Number of ATP under anaerobic glycolysis 2

PFK-1 is regulated by PFK-2

A product of glycolysis – 2,3 BPG combines with hemoglob9in and

unloads O2 to tissues.

Increase 2,3-BPG shifts O2 /Hb dissociation curve to right

Decrease 2,3-BPG shifts O2/Hb dissociation curve to left.

PDH COMPLEX:

Location – mitochondria

Enzyme complexes:-

1. E1 – pyruvate dehydrogenase – TPP

2. E2 – dihydro lipoyl transacetylase – lipoamide ,CoA

3. E3 – dihydro lipoyl dehydrogenase – NAD, FAD

Inhibitors – arsenic poisoning

TCA CYCLE:-


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Location – mitochondria

Citrate synthase - rate limitin step

NADH produce in :-

1. iso citrate dehydrogenase

2. α-ketoglutarate dehydrogenase

3. malate dehydrogenase

FADH produced by succinate dehydrogenase

GTP produced by succinate thiokinase

INHIBITORS:-

1. Aconitase – fluroacetate

2. Α-keto glutarate dehydrogenase – arsenate

3. Succinate dehydrogenase – malonate

Number of ATP produced from 1 Acetyl Co-A is 10.

GLUCONEOGENESIS:-

Synthesis of glucose from non-carbohydrate compounds.

160 gms of glucose required per day (whole body)

120 gms of glucose is required brain

Location:- initial step mitochondria ; key step – cytosol

Rate limiting step – pyruvate carboxylase


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Alanin glucogenic aminoacid

Glucagon stimulates gluconeogenesis, insulin inhibits

Αlpha- cells secrets glucagone

Alcohol inhibits gluconeogenesis induces hypoglycemia

GLYCOGEN METABOLISM

Liver glycogen maintains blood glucose

Muscle glycogen is used ony for muscle

Glycogenesis in muscle starts with hexokinase

Glycogenesis in liver starts with glucokinase

Glycogen in protein produced by liver acts as initiator of glycogen

synthesis

The tyrosine residue of glycogenin adds glucose from UDP-G to form

glycogen primer

Glycogen synthatase – rate limiting step in glycogen synthesis


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Glycogen phosphorylase breaks glycogen at α1-4 residues.

Glucagons stimulates glycogen breakdown in liver

Epinephrine stimulates glycogen breakdown in muscle

Calcium promotes glycogen breakdown by Ca+2 colmodulin complex

Glucose 6 phosphatase deficiency –Von Girek’s disease

Lysosomal α (1, 4) glucosidase deficiency – Pompe’s disease – heart is

more commonly involved – death occurs due to heart failure.

De-branching enzyme deficiency Anderson’s disease

Muscle glycogen phosphorylase deficiency –MC Ardle’s disease

Liver glycogen phosphorylase Her’s disease

Phosphofructokinase – Taruri’s disease – erythocytes, hemolysis

HMP PATHWAY:-

HMP pathway is only pathway which synthesizes NADPH in RBC

(required for antioxidant reaction)

Rate limiting step – glucose 6 phosphate dehydrogenase

Deficiency of glucose 6 phosphate dehydrogenase – hemolytic anemia

HMP pathway – synthesis of riboses

Transketolase dependent on TPP – decrease TPP – Werick’s

korsakoff syndrome

Glucose 6 phosphate dehydrogenase deficiency is resistant to malaria

Deficiency of xylitol dehydrogenase – essential pentosuria

GLACTOSE METABOLISM:-

CLASSICAL GALACTOSEMIA

Infants

Deficiency of galactose 1-phosphate Transferase uradyl.

Increase galactitol by aldose reductae – cataract diagnosis – elevated

galactose 1-phosphate uridyl transferase

FRUCTOSE METABOLISM:-

Deficiency of fructokinase essential fructosuria

Deficiency of aldolase-B hereditary fructose intolerance

Mucopolysaccharidoses-I – Iduronidase – Hurler’s syndrome

Mucopolysaccharidoses-II – iduronate sulfatase – Hunter’s syndrome

Mucopolysaccharidoses-III – sanfilippo syndrome

β- glucuronidase – sly syndrome (Mucopolysaccharidoses-VII)

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CARBOHYDRATE CHEMISTRY:-