Carbohydrates - Discussion PDF

**[CARBOHYDRATES]** **OVERVIEW:** Dietary carbohydrates include starch, sucrose, lactose and indigestible fibers. **Indigestible Fibers** - Fiber is a type of carbohydrate that the body can\'t digest. Though most carbohydrates are broken down into sugar molecules called glucose, fiber cannot be br...

**[CARBOHYDRATES]** **OVERVIEW:** Dietary carbohydrates include starch, sucrose, lactose and indigestible fibers. **Indigestible Fibers** - Fiber is a type of carbohydrate that the body can\'t digest. Though most carbohydrates are broken down into sugar molecules called glucose, fiber cannot be broken down into sugar molecules, and instead it passes through the body undigested. The major product of digestion of carbohydrates is glucose, but some Galactose and fructose are also produced. ***Glucose*** -- is a major fuel source that is oxidized by cells for energy. **Oxidized** - combine or become combined chemically with oxygen. After a meal, it is converted to glycogen or to TAG. Also converted to compound such as; proteoglycans, glycoprotein, and glycolipids. ***Fructose and Galactose*** -- converted to intermediates in the pathways by which the glucose is metabolized. ***Glycogen*** -- is the major storage forms of CHO in animals. The largest stores are in muscle and liver: - *Muscle Glycogen* -- used to generate ATP for muscle contraction. - *Liver Glycogen* - used to maintain blood glucose during fasting or exercise. The maintenance of blood glucose is a major function of the liver. **CARBOHYDRATES** Is the staff of life for the most organisms and the most abundant compound found in nature. Cellulose - is the most abundant carbohydrates and found in the woody structures and fibers of plants. TWO MAJOR BIOLOGICAL FUNCTIONS OF CHO: *1. as storage forms of fuel* - 1 g of CHO when oxidized will yield 4Kcal of energy - Glucose is the major source of energy in our body - Starch is the chief storage forms of CHO in most plant - Glycogen is the chief storage forms of CHO in animals *2. as structural elements* - Cellulose is the main structural component of the rigid cell wall - Acid mucopolysaccharides and proteoglycans are important structural polysaccharides in animal tissue. OTHER FUNCTIONS OF CHO: - Acts as a lubricants of skeletal joints - Major components of the cell wall of bacteria. - They provide adhesion between cells. - They confer biological specificity on the surface of animal cells. **CLASSIFICATION OF CHO:** CHO may be classified depending on the number of sugar unit they contain as: **I: Simple Sugar / Monosaccharide's** - Contain a single polyhdroxyl aldehyde or ketone unit Aldehydes - an organic compound containing the group ---CHO, formed by the oxidation of alcohols. Typical aldehydes include methanal (formaldehyde) and ethanal (acetaldehyde). Aldehydes are sweet-smelling compounds that are found in plants like rose and citronella. When these compounds are added as an ingredient in products like perfume, cologne and even laundry detergent, they help add a sweet or fresh scent. Ketones - any of a class of organic compounds (such as acetone) characterized by the presence of a carbonyl group attached to 2 CA. - They are those that cannot be hydrolyzed into a simpler form. - They have the empirical formula of CnH~2~n On - These sugars contains from 2-10 carbon atoms. - The names of the sugars end with "ose" SEVERAL METHODS OF NAMING THESE SUGARS: - According to the \# of carbon atoms: - Triose -- contains 3 carbon atoms (glyceraldehyde) - Tetrose -- 4 c.a. (erythrose) - Pentose -- 5 c.a. (ribose) - Hexose -- 6 c.a. (glucose) - According to the functional group they contain: - Aldoses -- those that contain the aldehyde group (mannose, Galactose) - Ketoses -- those that contain ketone group (fructose) - Combination of 1^st^ and 2^nd^ methods: aldotriose, ketopentose... - According to the ring structure: furanose (5 membered ring), pyranose (6 membered ring). IMPORTANT DERIVATIVES OF MONO: *1. Amino sugars* Two amino sugars that are widely distributed in plants and animals: - Glucosamine → product of hydrolysis of chitin -- the major polysaccharides of the shell of insects and crustaceans. - Galactosamine → found in the characteristic polysaccharides of cartilage and chondroitin sulfates. *2. Sialic acid -* They are actually a family compounds that contains 9 carbon atoms and are acetylated derivatives of neuraminic acid. Sialic acids - the term \"sialic acid\" (from the Greek for saliva. Sialic acids are found widely distributed in animal tissues and related forms are found to a lesser extent in other organisms like in some micro-algae, bacteria and archaea. In humans the brain has the highest sialic acid content, where these acids play an important role in neural transmission and ganglioside structure Ex: N-acetylneuraminic acid -- important building block of the oligosaccharide chains found in the glycoprotein and glycolipids of the cell coats and membranes of animal tissue. *N-acetylmuramic acid -* They are the major building block of the polysaccharides backbone of bacterial cell wall. **II: Compound Sugars /Oligosaccharides** - Contains from 2-10 sugar units. - Empirical formula: Cn(HnO)n Disaccharides -- the most important oligosaccharides. These are sugars which can be hydrolyzed into 2 monosaccharaides. Ex: - Glucose + glucose = maltose - Glucose + Galactose = lactose - Glucose + fructose = sucrose MALTOSE - least sweet sugars - malt sugars - Contained two D-glucose residues joined by a glycosidic linkage between carbon atom 1 (the anomeric carbon) of the 1^st^ glucose residue and carbon atom 4 of the 2^nd^ glucose A glycosidic bond or glycosidic linkage is a type of covalent bond that joins a carbohydrate (sugar) molecule to another group.. - Systemic name: O-D glucopyranosyl and β-D glucopyranose. Characteristics: - composed of 2 glucose units linked by 1:4 glycosidic bond - Exhibit mutarotation, because of free anomeric carbon. Mutarotation is a difference in the specific rotation of plane-polarized light, due to the change in the equilibrium between two anomers in the solution. Mutarotation property was first observed in sugar. The anomeric carbon can be determined by the carbon (C) attached to two oxygen (O) atoms joined by single bonds. This rotation brings about two distinct configurations, α and β -anomers. - can react with excess phenyl hydrazine to form maltosazone crystals - can be formed through enzymatic hydrolysis of starch - it is a glucose-glucoside - a repeating disaccharide units of starch and glycogen. LACTOSE - Formed by mammary gland and occurs to the extent of about 5% in milk. - On hydrolysis, it yields D-galactose and D-glucose. Characteristics: - A reducing disaccharides, because of the potentially free carbonyl group. In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. - Exhibit mutarotation, therefore it exists α-β anomers. Beta-anomers (β-anomers): A carbohydrate in which the group bonded to the anomeric carbon is cis to the CH2O group on the other side of the pyranose or furanose ring ether oxygen atom. - It is dextrorotatory, it forms lactosazone with phenylhydrazine. Dextrorotatory - (of a compound) having the property of rotating the plane of a polarized light ray to the right, i.e. clockwise facing the oncoming radiation. Turning clockwise or toward the right specifically: rotating the plane of polarization of light toward the right dextrorotatory crystals --- compare levorotatory. SUCROSE - also called saccharose or cane sugars - ordinary table sugar - very soluble and very sweet - In contrast to maltose and lactose, sucrose contains no free anomeric carbon. Characteristics: - because of the absence of free or potentially free anomeric carbon, sucrose is not a reducing sugar - will give (-) result in Benedict's test - does not exhibit mutarotation - Cannot form osazone crystals with seliwanoff's test. **III: Polysaccharides** - these groups contain more than 10 sugar units - empirical formula: (C~6~H~10~O~5~)~X~ Another term for polysaccharides is glycans. It is suggested that polysaccharide such as starch, glycogen and cellulose which are made up of a single kind of monosaccharide be called ***"HOMOGLYCANS"*** and that polysaccharides composed of 2 or more kinds of monosaccharide such as mucopolysaccharides be called ***"HETEROGLYCANS".*** CLASSIFICATION OF POLYSACCHARIDES: 1. HOMOPOLYSACCHARIDES (HOMOGLYCANS) - Contain only 1 type of sugar unit. Glucosans -- the most important of the single polysaccharide. *Ex:* - STARCH. The most important food source of CHO. It contains 2 type of glucose polymers: - Amylose -- constitute 15-20% of starch. It forms helical structure responsible for the blue black color with iodine. Amylose is a linear polymer with 200 to 2000 α-linked glucose units that serves as a major source of food for some animals. It is known as the "starchy, non-sticky starch" in cooking. It does not dissolve in water, and high levels of amylose help grains, like rice, maintain their shape. In food manufacturing, some companies use amylose as a stabilizer and thickener. - Amylopectin -- constitute 80-85% of starch. Amylopectin is a water-insoluble polysaccharide and highly branched polymer of α-glucose units found in plants. Enzymes that hydrolyze starch are called: - α amylase -- animal origin and it is found in the GIT especially in the saliva (ptyalin) and pancreatic juice (amylopsin) - β amylase -- a plant origin. - DEXTRIN. When starch is partially hydrolyzed by the action of acid or enzyme, it is broken down to\# of products of lower molecular weight known as dextrins. - DEXTRAN. Important in medicine, because of its use a plasma expander or substitute in the treatment of hypovolemic shock. A plasma volume expander made from natural sources of sugar (glucose). It works by restoring blood plasma lost through severe bleeding. Severe blood loss can decrease oxygen levels and can lead to organ failure, brain damage, coma, and possibly death. - GLYCOGEN. This is the form in which CHO is stored in the animal organisms, thus it is called animal starch. - CELLULOSE. The chief constituent of the fibrous parts of plant and it helps in the formation of normal stool. It also relieves constipation if taken moderate amount. - INULIN. Used in testing kidney function and in other studies of renal physiology. Inulin is a type of prebiotic. It\'s not digested or absorbed in the stomach. It stays in the bowel and helps certain beneficial bacteria to grow. 2. HETEROPOLYSACCHARIDES (HETEROGLYCANS) - Contains more than 1 type of sugar units. Acid Mucopolysaccharides (glycosaminoglycans) - A group of structural and protective polysaccharides. They are called mucins or mucoprotein, also referred to as proteoglycans. *Ex:* - HYALURONIC ACID. The most abundant acid mucopolysaccharides and present in cell coats and in the extracellular ground substances of the connective tissues. It also occurs in the synovial fluid in joints and vitreous humor of the eye. - CHONDROITIN SULFATES. It is the major structural components of cell coats, cartilage, bone, cornea, skin and other connective tissue. - HEPARIN. It is very powerful inhibitors of blood clotting. Heparin is used to prevent blood clots from forming in people who have certain medical conditions or who are undergoing certain medical procedures that increase the chance that clots will form. Heparin is also used to stop the growth of clots that have already formed in the blood vessels, but it cannot be used to decrease the size of clots that have already formed. Heparin is used to prevent or treat certain blood vessel, heart, and lung conditions. Heparin is also used to prevent blood clotting during open-heart surgery, bypass surgery, kidney dialysis, and blood transfusions **IV: Derived Carbohydrates** - Derived by certain chemical reactions on sugars. Ex: - OXIDATION PRODUCT -- sugar acids - Glucoronic acid - it is important in detoxication reaction or conjugation reaction in our body. - Ascorbic acid or vitamin C - one of the most important sugar acids. A derivative of hexonic acid. Present in large amount in citrus fruits and tomatoes - REDUCTION PRODUCT -- sugar alcohol - Mannitol (mannose) - an osmotic diuresis - Is generally used for certain non-electrolyte that are rapidly excreted and the presence of which in the urine leads to an increase in urine volume. Has been employed in the management of the early phases of acute oliguria (↓ urine volume). - Galactitol (Galactose) - this substance is the cause of cataract (opacity of the lens of the eye) in infants suffering from galactosemia. - AMINO SUGARS - DEOXY SUGARS Ex: D-2 deoxyribose............................. **LABORATORY DISCUSSION** EX OF SIMPLE SUGARS: - Glucose - Galactose -- synthesized in the mammary gland to make lactose of milk. - Fructose -- the sweetest among sugars and also called as laevulose. It is insoluble in distilled water, 10% NaCl, 2% HCl, 95% ROH. EX OF REDUCING SUGARS: - Maltose - Lactose - Glucose - Galactose - Fructose STARCH -- microscopic fine irregular crystal with clear white color. A tasteless sugar and polymer of lactose **DIFFERENT TYPES OF SUGARS:** MANNOSE Impt: occurring in glycoprotein Source: hydrolysis of plant gum GLUCOSE Impt: sugar of the body Source: hydrolysis of starch, cane sugar, maltose and lactose FRUCTOSE Impt: can be charged to glucose in the liver and intestine Source: hydrolysis of cane sugar and insulin RIBOSE Impt: structural elements of nucleic acid and co-enzyme Source: nucleic acid ARABINOSE Impt: used in the studies of bacterial metabolism Source: gum Arabic, cherry gum, plum (dried grapes or raisin) LYXOSE Impt: isolated from human heart muscle Source: heart muscle XYLOSE Impt: used in the studies of bacterial metabolism Source: wood gums, proteoglycans, glycosaminoglycan's GALACTOSE Impt: constituent of glycolipids and glycoprotein Source: hydrolysis if lactose RIBULOSE Impt: intermediate in hexose monophosphate shunt Source: formed in metallic process **DIFFERENT TESTS FOR SUGARS (COLOR REACTION TEST):** - MOLISCH'S TEST Rgt and Procedure: α-napthol, then heat with concentrated H2SO4, general test for CHO Product Responsible for color: furfural and hydroxyfurfural Is not a specific test for CHO, but a (-) results is a good evidence of the absence of CHO. (+) result: reddish violet ring at the junction. - FEHLING'S TEST Fehling's reagent is prepared in 2 separate solutions: Fehling's A (CuSO~4~) and Fehling's B (NaOH, NaK^+^ tartrate -- Rochelle salt). Fehling's mixture is very strong alkaline solution. Rgt and Procedure: CuSO~4,~ sodium tartrate (+) result: orange color - BENEDICT'S TEST This test has the same principle as the Fehling's. The difference is in the Fehling's reagent alkali which is NaCO~3~ and the salt is trisodium citrate. Benedict's reagent is less alkali then (+) result: reduction is indicated by a precipitate which may vary from green, yellow or red depending on the amount of sugar present. - BARFOED'S TEST A reduction test for sugar in acid media Rgt and Procedure: copper acetate in acetic acid. (+) result: reduction is indicated by the formation of a brick red precipitate of cuprous oxide. Two things must be taken into consideration as to be able to differentiate monosaccharide from disaccharides: - time element - concentration **TEST FOR REDUCING PROPERTY OF SUGARS:** - Fehling's - Benedict's - Barfoed's **TEST FOR REDUCTION PROPERTY IN ALKALINE MEDIA:** - Benedict's - Barfoed's - Osazone Test -- the formation of an osazone with phenyl hydrazine is another carbonyl reaction of the sugars being due to the presence of the aldehyde or ketone group. Presence of osazone crystals. **SPECIFIC TEST FOR SUGARS:** - SELIWANOFF'S TEST (resorcinol - HCl test) - Specific test for ketose sugar. Rgt and Procedure: HCl + resorcinol, differentiates aldohexoses from ketohexoses (+) result: bright cherry red with ketohexoses; pale pink with aldohexoses - BIAL'S ORCINOL TEST -- formation of the silver mirror in the side of the tube - ORCINOL AND TOLLENS TEST -- specific test for pentose sugar **OTHER TESTS FOR SUGARS:** - MUCIC ACID TEST -- a test to differentiate galactose and lactose from other reducing sugars. - IODINE TEST -- general test for polysaccharides. A blue-black precipitate is a (+) test for starch. **CLINICAL ASPECTS: CHO METABOLISM** **Diabetes Mellitus** - The most common disease related to CHO metabolism - Characterized by insufficient levels of active insulin. - A disease characterized primarily by abnormally high levels of glucose in the body. - A syndrome with multiple causes -- because it occurs as 1^0^ or 2^0^ disorder to a certain disease. - A common disorders associated with CHO metabolism due to insufficient levels of active insulin. Diabetes -- means running through, referring to the characteristic diuresis (↑ the secretion of urine). Mellitus -- sweet or honey like, referring to the presence of large amount of glucose in urine. CHO Metabolism in DM: - Occurs when there is glycogen depletion due to glucose deficient - ↑ CHON catabolism to become alanine - Glucose thru gluconeogenesis - ↑ BS level Reasons Why Insulin Is Insufficient: - Pancreatic disease - Destruction of islet cells - Pancreatectomy -- surgical removal of the pancreas. - Number of insulin receptors is ↓ or abnormal - Over secretion of the somatostatin. **Pathways in Glucose Metabolism:** - Glycolysis- metabolism of glucose molecule to pyruvate or lactate for production of energy - Gluconeogenesis - is the conversion of AA by the liver and other specialized tissues such as the kidney to substrates that can be converted to glucose. It also encompasses the conversion of glycerol, lactate and pyruvate to glucose. - Glycogenolysis - breakdown of glycogen to glucose for use of energy. - Glycogenesis - conversion of glucose to glycogen for storage. - Lipogenesis - conversion of CHO to FA. - Lipolysis - decomposition of fats. **Hormones Which Control Glucose:** - *Insulin* - the 1^0^ hormone responsible for the entry of glucose into the cells. It is synthesized by the β cells of the **islet of Langerhans** in the pancreas. The only hormone that ↓'s glucose level and can be referred to as hypoglycemic agent. Action of Insulin in CHO Metabolism: - ↑ glycogenesis and glycolysis - ↑ lipogenesis - ↓ glycogenolysis - *Glucagon-* the 1^0^ hormone responsible for ↑'ing glucose levels. It synthesized by the alpha cells of islet of Langerhans in the pancreas and is released during stress and fasting state. Actions of Glucose in CHO Metabolism: - ↑'s glycogenolysis in the liver and ↑ in gluconeogenesis and it can be referred to as hyperglycemic agents. - Enhances release of glucose from glycogen. - Enhances release of glucose from AA or FA. - *Somatostatin-* produced by the δ cells of the islet of Langerhans in the pancreas. Actions: - It ↑'s plasma glucose levels by inhibition of insulin, glucagon, GH and other endocrine hormones. - *Catecholamine* 2 hormones produced by the adrenal glands affect in CHO metabolism: 1. Epinephrine - Produced by the adrenal medulla - The inner part of the adrenal gland (a small organ on top of each kidney) - ↑'s plasma glucose by inhibiting insulin secretion. - ↑glycogenolysis and promoting lipolysis. 2. Glucocorticoids - primarily cortisol, are released from the adrenal cortex (zona fasciculata and zona reticularis) on stimulation by ACTH (adrenocorticotrophic hormone). CORTISOL - an essential hormone that affects almost every organ and tissue in your body. It plays many important roles, including: Regulating your body\'s stress response or danger. Helping control your body\'s use of fats, proteins and carbohydrates, or your metabolism. Suppressing inflammation. ACTH - a tropic hormone produced by the anterior pituitary Actions: - It ↑'s plasma glucose by ↓'ing intestinal entry into the cell and ↑'ing gluconeogenesis, liver glycogen and lipolysis. - *Growth hormone*- produced and secreted by the somatotrophic cells of the anterior pituitary. Actions: - It ↑'s plasma glucose by ↓'ing the entry of glucose into the cells and by ↑'ing glycolysis **Classification of DM:** **A) Primary DM** - based on the activity and state of the pancreas involving the insulin producing cells. ***Types:*** **1. Type I / IDDM or Insulin Dependent Diabetes Mellitus** - characterized by inappropriate hyperglycemia primarily due to pancreatic islet β cells destruction. - occurs at an early age (juvenile onset) before 30 y/o - seen in thin patient - Abrupt onset of symptoms - Sudden onset symptoms are symptoms that develop quickly. They can also be called quick onset symptoms or acute symptoms. - insulin dependent/ requires insulin for treatment - ketosis prone -- a metabolic state characterized by raised levels of ketone bodies in the body tissues, which is typically pathological in conditions - Congenital -- not hereditary. *S/sx (sign and symptoms):* - Polydypsia -- excessive thirst as a response to an excessive water loss via urination. - Polyphagia - ↑ food intake - Polyuria -- excessive urine production due to osmotic diuresis. - rapid weight loss - hyperventilation - mental confusion - skin is warm but not dry - breath has a sweet, fruity odor - loss of consciousness (due to ↑ glucose to brain) *Complication Include:* - heart disease - microvascular problem such as: - Nephropathy - deterioration of kidney function. The final stage of nephropathy is called kidney failure, end-stage renal disease (ESRD). - Neuropathy - a nerve problem that causes pain, numbness, tingling, swelling, or muscle weakness in different parts of the body - Retinopathy - disease of the retina. There are several types of retinopathy but all involve disease of the small retinal blood vessels. **2. Type II /NIDDM or Non-Insulin Dependent Diabetes Mellitus** - characterized by hyperglycemia due to an individual's resistance to insulin with an insulin secretory defect. - occurs after age of 40 (maturity onset) - seen in obese or have an ↑ed percentage of body fat distribution in the abdominal region - gradual onset of symptoms - ketosis resistant - requires drug that potentiate insulin - hereditary and genetically linked **B) Secondary DM** - associated with other endocrinopathies: - Cushing syndrome -- a disease of the adrenal cortex causing excessive secretion of diabetogenic Glucocorticoids. - Pheochromocytoma -- a tumor involving the chromocytes of the adrenal medulla causing excessive production of epinephrine. - Acromegaly -- a disease characterized by enlargement of the bones of the hand, feet, and skull due to excessive amount of GH. C\) Gestational DM (GDM) - is any degree of glucose intolerance with onset or first recognition during pregnancy. The causes of GDM include: metabolic and hormonal changes. Infants born to diabetic mother are at increased risk for respiratory distress syndrome, hypocalcaemia and hyperbilirubinemia. RESPIRATORY DISTRESS SYNDROME (RDS) - is a breathing problem that sometimes affects babies born six weeks or more before their due dates. Their lungs aren\'t developed enough to make surfactant, a liquid that coats the inside of the lungs and keeps them open so that the baby can breathe in air once he or she is born. HYPOCALCEMIA - the calcium level in blood is too low. A low calcium level may result from a problem with the parathyroid glands, as well as from diet, kidney disorders, or certain medications. HYPERBILIRUBINEMIA - a condition in which there is too much bilirubin in your baby\'s blood. When red blood cells break down, a substance called bilirubin is formed. **Criteria for Diagnosis of DM: -** The process of identifying a disease, condition, or injury from its signs and symptoms. According to the new American Diabetes Association (ADA) recommendation, testing should be carried out at an early age or more frequently in individuals who displays: - obesity (120% of desirable body weight or body mass index of 27 kg) - family history of diabetes in a 1^st^ degree relatives - membership in a high risk minority population (African-American, Hispano-American, Native-American) - history of GDM or delivering a baby \> 9lbs ( \> 4.1 kg) - HPN (\> 140/90) - low HDL cholesterol concentration ( \< 35 mg/dl) - elevated TAG concentration (\> 250 mg/dl) - history of impaired fasting glucose / impaired glucose tolerance An intermediate group that did not meet the criteria of DM but had glucose levels above normal was defined by 2 methods: - *impaired fasting glucose* - those patient with fasting glucose levels ≥ 110 mg/dl but \< 126 mg/dl - *impaired glucose tolerance* - to indicate glucose tolerance values above normal but below diabetes level. Patient who had 2H OGTT (oral glucose tolerance test) levels of ≥ 140 mg/dl but \< 200 mg/dl. GDM is diagnosed when any 2 of the following 4 values are meeting or exceeded: - fasting: \> 105 mg/dl - 1H: \> 190 mg/dl - 2H: ≥ 165 mg/dl - 3H: ≥ 145 mg/dl **Diagnostic Criteria for DM (According to ADA): -** A test used to help figure out what disease or condition a person has based on their signs and symptoms **1. FBS (Fasting Blood Sugar)** - the preferred test for diagnosing diabetes - 8-14 H fasting - used to detect elevation in glucose concentration either [hyperglycemia] or [hypoglycemia. ] [Hyperglycemia:] - ↑ plasma glucose levels. It may be secondary to other endocrine diseases, or even be due to an abnormal to the insulin receptors. *Laboratory Findings in Hyperglycemia:* - ↑ glucose in plasma and urine - ↑ urine specific gravity -- term used to express density - ↑ Serum and urine osmolality. Osmolality is a physical property of a solution, based on the concentration of solutes per kg of solvent. - Ketones in serum and urine (Ketonemia and ketonuria). Ketone bodies is the product of incomplete fat metabolism. - ↓ blood and urine pH (acidosis). [Hypoglycemia:] - ↓ BS level due to hyperinsulinism from lack of glucose. A syndrome characterized by low plasma glucose and an associated group of symptoms that are relieved by ingestion of foods or CHO. - It can be classified as [post absorptive (fasting)] and [post] [Prandial (reactive]) hypoglycemia. [Fasting hypoglycemia] - An individual can rely on gluconeogenesis to maintain the extracellular glucose concentration. A serious form of disease, usually with some underlying metabolic condition. [Reactive hypoglycemia] - Usually not a serious form of disease. It include an excessive release of insulin that results in glucose levels dropping below normal fasting levels. - ↓ plasma glucose levels ad can have many causes like insulinomas - one of the most important cause of hypoglycemia. Tumor of the pancreas. - it is excessive and inappropriate secretion of insulin by pancreatic beta tumor such as: - Mesotheliomas - a cancer affecting the mesothelial cells which cover most internal organs - Hepatic carcinomas - occurs when a tumor grows on the liver. - Adrenocortical tumor - a rare, aggressive cancer that affects your adrenal gland. - Gastrointestinal carcinomas - refers to malignant conditions of the gastrointestinal tract and accessory organs of digestion, including the esophagus, stomach, biliary system, pancreas, small intestine, large intestine, rectum and anus. Symptoms of tumors: - ↑ hunger, sweating, nausea, vomiting, dizziness, nervousness, shaking, blurring of speech and sight, mental confusion Laboratory Findings Include: - ↓ plasma glucose levels during hypoglycemic episodes - extremely elevated insulin levels in β cells tumor (Insulinomas) Categories of Fasting Plasma Glucose/FBS: - normal fasting glucose: FPG \< 110mg/dl - impaired fasting glucose: FPG ≥ 110 mg/dl and 126 mg/dl - provisional diabetes diagnosis: FPG ≥ 126 mg/dl NV of FBS: 70-110 mg/dl **2**. **RBS (Random Blood Sugar)** - -anytime. NV: 45-130 mg/dl **3.** **2H PPT (2 Hours Post Prandial Test)** - The most modern approach to GTT (glucose tolerance test) and more sensitive index of DM. NV: \< 130 mg/dl **4. OGTT (Oral Glucose Tolerance Test)** - Not recommended for routine use under the new ADA guidelines. This procedure is not inconvenient to patient and is not being used by physician for diagnosing diabetes. However, if the OGTT is used, WHO recommends the criteria: - normal glucose tolerance: 2H PG \< 140 mg/dl - impaired glucose tolerance: 2H PG ≥ 140 mg/dl and \< 200 mg/dl - provisional diabetes diagnosis: 2H 200 mg/dl Confirmatory Test For GTT (Used To Measure Liver Function): - OGTT (Oral Glucose Tolerance Test) - oral, because the glucose challenge administered orally. *Factors to be considered:* - patient must be on full -- well balanced diet (minimum of 80 g of CHON and 150 g of CHO) 3 days prior to the test. - Patient must be ambulatory -- smoking and exercise are not allowed before and during the test. - Fasting for 8-14H (overnight) -- the test should be performed in the morning. - Administered glucose challenged -- 75 grams of glucose load must be given. - 100g -- pregnant - 75g -- adult - 1.75g/kg body weight -- child - IGTT *(*Intravenous Glucose Tolerance Test) - used for gastrointestinal disease and Gastroenterectomy -- surgical formation of a connection between stomach and small intestine. Diagnostic Criteria for DM: - RBS: ≥ 200 mg/dl (11.1 mmol/L) - FBS: ≥ 126 mg/dl (7.0 mmol/L) - 2H PG: ≥ 200 mg/dl (11.1 mmol/L) during an OGTT\> **ADDITIONAL INFORMATION** **Indigestible Fibers** - Fiber is a type of carbohydrate that the body can\'t digest. Though most carbohydrates are broken down into sugar molecules called glucose, fiber cannot be broken down into sugar molecules, and instead it passes through the body undigested. **Oxidized** - combine or become combined chemically with oxygen. **Aldehydes** - an organic compound containing the group ---CHO, formed by the oxidation of alcohols. Typical aldehydes include methanal (formaldehyde) and ethanal (acetaldehyde). Aldehydes are sweet-smelling compounds that are found in plants like rose and citronella. When these compounds are added as an ingredient in products like perfume, cologne and even laundry detergent, they help add a sweet or fresh scent. **Ketones** - any of a class of organic compounds (such as acetone) characterized by the presence of a carbonyl group attached to 2 CA. **Hydrolysis** - the chemical breakdown of a compound due to reaction with water. The word hydrolysis comes from the word hydro, which is Greek for water, and lysis, which means \"to unbind.\" In practical terms, hydrolysis means the act of separating chemicals when water is added. **Acid mucopolysaccharides** -- is a test that measures the amount of mucopolysaccharides released into the urine either during one episode or over a 24-hour period. **Cartilage** is a strong, flexible connective tissue that protects your joints and bones. It acts as a shock absorber throughout your body. Cartilage at the end of your bones reduces friction and prevents them from rubbing together when you use your joints. Cartilage has many functions, including the ability to resist compressive forces, enhance bone resilience, and provide support on bony areas where there is a need for flexibility. **Chondroitin sulfate** is a chemical found in human and animal cartilage. It is commonly used by mouth with glucosamine or other ingredients for osteoarthritis. **Chondroitin** helps keep cartilage healthy by absorbing fluid (particularly water) into the connective tissue. It may also block enzymes that break down cartilage, and it provides the building blocks for the body to produce new cartilage. **Sialic acids** - the term \"sialic acid\" (from the Greek for saliva. Sialic acids are found widely distributed in animal tissues and related forms are found to a lesser extent in other organisms like in some micro-algae, bacteria and archaea. In humans the brain has the highest sialic acid content, where these acids play an important role in neural transmission and ganglioside structure **A glycosidic bond or glycosidic linkage** is a type of covalent bond that joins a carbohydrate (sugar) molecule to another group. **Mutarotation** is a difference in the specific rotation of plane-polarized light, due to the change in the equilibrium between two anomers in the solution. Mutarotation property was first observed in sugar. In organic chemistry, a **carbonyl group** is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. **Beta-anomer** (β-anomer): A carbohydrate in which the group bonded to the anomeric carbon is cis to the CH2O group on the other side of the pyranose or furanose ring ether oxygen atom. The **anomeric carbon** can be determined by the carbon (C) attached to two oxygen (O) atoms joined by single bonds. This rotation brings about two distinct configurations, α and β -anomers. **Dextrorotatory** - (of a compound) having the property of rotating the plane of a polarized light ray to the right, i.e. clockwise facing the oncoming radiation. Turning clockwise or toward the right specifically: rotating the plane of polarization of light toward the right dextrorotatory crystals --- compare levorotatory. **Amylose** is a linear polymer with 200 to 2000 α-linked glucose units that serves as a major source of food for some animals. It is known as the "starchy, non-sticky starch" in cooking. It does not dissolve in water, and high levels of amylose help grains, like rice, maintain their shape. In food manufacturing, some companies use amylose as a stabilizer and thickener. **Amylopectin** is a water-insoluble polysaccharide and highly branched polymer of α-glucose units found in plants. A **plasma volume expander** made from natural sources of sugar (glucose). It works by restoring blood plasma lost through severe bleeding. Severe blood loss can decrease oxygen levels and can lead to organ failure, brain damage, coma, and possibly death. **Inulin** is a type of prebiotic. It\'s not digested or absorbed in the stomach. It stays in the bowel and helps certain beneficial bacteria to grow. **Hyaluronic acid** is a natural substance found in the fluids in the eyes and joints. It acts as a cushion and lubricant in the joints and other tissues. Different forms of hyaluronic acid are used for cosmetic purposes. Hyaluronic acid might also affect the way the body responds to injury and help to decrease swelling. Hyaluronic acid helps skin stretch and flex and reduces skin wrinkles and lines. Hyaluronic acid is also proven to help wounds heal faster and can reduce scarring. **Synovial fluid** is a thick liquid located between the joints. A synovial fluid analysis checks for disorders that affect the joints. Synovial fluid, also known as joint fluid, is a thick liquid located between your joints. The fluid cushions the ends of bones and reduces friction when you move your joints. **Heparin** is used to prevent blood clots from forming in people who have certain medical conditions or who are undergoing certain medical procedures that increase the chance that clots will form. Heparin is also used to stop the growth of clots that have already formed in the blood vessels, but it cannot be used to decrease the size of clots that have already formed. Heparin is used to prevent or treat certain blood vessel, heart, and lung conditions. Heparin is also used to prevent blood clotting during open-heart surgery, bypass surgery, kidney dialysis, and blood transfusions