Chromium Chromium Cr Dietary Sources Bioavailability Regulation l

Chromium

Chromium (Cr): Dietary Sources, Bioavailability, & Regulation l l l Food content depends on soil Whole grains, fruits/veg, processed meats, dairy and fish Bioavailability affected by: • Vitamin C • Acidic medications • Antacids Transported in blood to liver Excess excreted in urine & feces

Functions of Chromium l l Regulates insulin • Synergistic with insulin in its action for glucose utilization Growth & development • Increases lean mass • Decreases fat mass

Chromium Deficiency & Toxicity l Deficiency l Toxicity • �� Hospitalized patients • �� Elevated blood glucose • �� Decreased insulin sensitivity • �� Weight loss • �� Rare • �� Industrially released chromium can be toxic at very high levels

Manganese (Mn): l l RDA 4 mg Blood 4– 20 micro gm / dl

Manganese (Mn): Dietary Sources & Regulation Whole grains, pineapples, nuts, legumes, dark green leafy vegetables, water l <10% absorbed l Excess incorporated into bile & excreted in feces l

Functions of Manganese l Cofactor for metalloenzymes l Cofactor for superoxide dismutase Mn dependant enzymes: decarboxylase, phosphatase, glycerol transferase etc Digestion of food Supports immune system l l l • �� Gluconeogenesis • �� Bone formation

Functions of Manganese l l Regulates blood sugar level Production of energy & cell reproduction Bone growth Supports blood clotting along with Vitamin K

Manganese Deficiency & Toxicity l Deficiency l Toxicity ( Total Mn content above 10 mg ) • Rare • Scaly skin, poor bone formation, growth retardation • Rare • Mining • Liver disease • Psychosis • Parkinsonism like symptoms

Selenium l l Se is essential trace element at lower concentrations Toxic at higher concentrations Essential for production of steroids hormones like testosterone Requirement • 3— 4 micro gm / d

Absorption, Metabolism, & Regulation of Selenium Most Se enters blood l Incorporated into selenomethionine l Makes selenoproteins l Stored in muscles l Maintenance of Se through excretion in urine l

Functions of Selenium Component of glutathione peroxidase • catalyzes removal of hydrogen peroxide • GSH + H 2 O 2 GSSG + H 2 O • GSH = reduced glutathione • GSSG = oxidized glutathione Component of iodothyronine-5’- deiodinase • Converts T 4 to T 3 Improves killing ability of neutrophils • Reduces the prevalence and severity of mastitis

Functions of Selenium l l l Responsible for normal pancreatic function Digestion and absorption of fats & vitamin E For ATP synthesis For synthesis of steroids and related compounds Protective role against antioxidants

Selenium Deficiency & Toxicity l Deficiency • Keshan disease ( cardiomyopathy ) • Muscular dystrophy • Stiff limb disease • Liver dystrophy • Muscular degeneration

Selenium Deficiency & Toxicity l l Toxicity Above 15 micro gm • Garlic-like odor of breath • Nausea • Vomiting • Diarrhea • Brittleness of teeth & fingernails • Loss of hair
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