CholesterolCholesterolSoňa Lichovníková a Marek KulíšekSoňa Lichovníková a Marek Kulíšek

xclichovnikova@fch.vutbr.czxclichovnikova@fch.vutbr.cz

xckulisek@fch.vutbr.czxckulisek@fch.vutbr.cz

What is it?

• Cholesterol is a Cholesterol is a lipid substancelipid substance, it belongs , it belongs to sterols and it has quite complicated to sterols and it has quite complicated molecule (several carbon rings).molecule (several carbon rings).

• It is a basic unit of cell-walls (It is a basic unit of cell-walls (membranesmembranes), ), participates in forming of participates in forming of sex hormonessex hormones, , hormones of adrenal gland and bile acids.hormones of adrenal gland and bile acids.

• Cholesterol generates Cholesterol generates vitamin Dvitamin D, it is , it is important in structure of nerve cellsimportant in structure of nerve cells

How does it look like?How does it look like?

• 4 carbon rings with a 4 carbon rings with a side chain - has 8 side chain - has 8 carbonscarbons

• Belongs to steroidsBelongs to steroids• Subgroup of sterols Subgroup of sterols

(due to OH group)(due to OH group)• Lipid groupLipid group

• lipids - heterogenous material group, lipids - heterogenous material group, characteristic qualities: characteristic qualities: – Insolubility in waterInsolubility in water– Solubility in organic solventsSolubility in organic solvents

• Occcurs in all body cells, mostly in nerve Occcurs in all body cells, mostly in nerve tissuetissue

• Also in animal fats, not in vegetable fatsAlso in animal fats, not in vegetable fats

Metabolism of cholesterol Metabolism of cholesterol synthesissynthesis

• about about 1g/day1g/day originates by originates by synthesissynthesis

• about about 0,3g/day0,3g/day extracted extracted from foodfrom food

• Cholesterol is synthesized in :Cholesterol is synthesized in :– liver, small intestineliver, small intestine, adrenal cortex, skin, , adrenal cortex, skin,

aortaaorta

• first level of metabolic pathway is acetyl-first level of metabolic pathway is acetyl-COA. Than follows more than 20 reactions COA. Than follows more than 20 reactions

Metabolism of cholesterolMetabolism of cholesterolsecretionsecretion

• Cholesterol is secreted in 2 main ways: Cholesterol is secreted in 2 main ways: – Conversion on bile acidsConversion on bile acids– Excretions of neutral sterols by stoolExcretions of neutral sterols by stool

• Synthesis of steroid hormone from Synthesis of steroid hormone from cholesterol and elimination of their cholesterol and elimination of their degradation products by urine.degradation products by urine.

In what food it is?In what food it is?

• Product of animal metabolismProduct of animal metabolism

meatmeat

liverliver

brainbrainegg yolkegg yolk

• It is risky to use technology which leads to heating up cholesterol with air (desiccation of It is risky to use technology which leads to heating up cholesterol with air (desiccation of milk and eggs, rendering of butter and lard – žluknutí – butter and lard turning rancid)milk and eggs, rendering of butter and lard – žluknutí – butter and lard turning rancid)

Where can it be found in body?Where can it be found in body?

• free, or in form of cholesterol esters with free, or in form of cholesterol esters with fatty acidsfatty acids

• Their transport is allowed in blood only in Their transport is allowed in blood only in form of specific elements - form of specific elements - lipoproteinslipoproteins, in , in which fats are bound on which fats are bound on proteins proteins transmiterstransmiters in combination with in combination with tryglicerides.tryglicerides.

Types of lipoproteinsTypes of lipoproteins

• Lipoproteins with high density (HDL)Lipoproteins with high density (HDL) - less - less cholesterol than LDL and more amount of cholesterol than LDL and more amount of proteins.proteins.

• Lipoproteins with low density (LDL)Lipoproteins with low density (LDL) – risky for – risky for organism, transmits much of cholesterol in blood organism, transmits much of cholesterol in blood and it more often inlay in vascular walls and it and it more often inlay in vascular walls and it makes them thinner. makes them thinner.

• Lipoproteins with very low density (VLDL)Lipoproteins with very low density (VLDL) – aren – aren´t so important like LDL and HDL, contains quite ´t so important like LDL and HDL, contains quite small amount of cholesterol.small amount of cholesterol.

Occurrence in world?Occurrence in world?• Low levels of HDL - smokers and Low levels of HDL - smokers and

overweight persons.overweight persons.• High levels of HDL – in some long-lived High levels of HDL – in some long-lived

families.families.• High levels of HDL – persons with good High levels of HDL – persons with good

physical shape, also moderate periodic physical shape, also moderate periodic consummation of alcohol can increase consummation of alcohol can increase HDL.HDL.

• higher occurrence of ischemic heart disease in higher occurrence of ischemic heart disease in USA and in Europe. (Czech republic - third).USA and in Europe. (Czech republic - third).

Diseases which are caused due to Diseases which are caused due to cholesterolcholesterol

• cholesterol stores into vessels in the form of cholesterol stores into vessels in the form of itit’s’s compounds – necking of vessels, ISCH, compounds – necking of vessels, ISCH, ateriosclerosisateriosclerosis

• Amount of cholesterol - optimal 300 mg per day Amount of cholesterol - optimal 300 mg per day and less.and less.

Genetics and it´s roleGenetics and it´s role(look at our parents)(look at our parents)• Synthesis and degradation of Synthesis and degradation of

cholesterol is genetically cholesterol is genetically predicted.predicted.

• But the main influence have also But the main influence have also outer conditions, mainly the food outer conditions, mainly the food we eat.we eat.

How to reduce cholesterol?How to reduce cholesterol?

• Lower also income of sugars and maily alcoholLower also income of sugars and maily alcohol• medicaments: statines, fibrates and their medicaments: statines, fibrates and their

combinationcombination

CuriositiesCuriosities

• For the first time For the first time cholesterol was cholesterol was isolated in 18th isolated in 18th century from bile century from bile stones.stones.

• Another research Another research found that this steroid found that this steroid alcohol occurs in all alcohol occurs in all cells of human body.cells of human body.

CuriositiesCuriosities

• Cholesterol under microscope

ReferencesReferences

• http://www.lekarna.cz/detail.php?id=122http://www.lekarna.cz/detail.php?id=122• http://www.brnacek.cz/poradna/zivot/2.htmhttp://www.brnacek.cz/poradna/zivot/2.htm• http://www.faf.cuni.cz/Gerontology/nutrition/agedependence/http://www.faf.cuni.cz/Gerontology/nutrition/agedependence/

Agedependence.aspAgedependence.asp• http://www.fitnet.cz/vyziva/ZSP02.htmlhttp://www.fitnet.cz/vyziva/ZSP02.html• http://www1.lf1.cuni.cz/~zfisar/bhap/6dalsi.htm#6_2http://www1.lf1.cuni.cz/~zfisar/bhap/6dalsi.htm#6_2• http://www.pacienti.cz/hcy-PS04.htmhttp://www.pacienti.cz/hcy-PS04.htm• http://www.referaty.sk/index.php?referat=3355http://www.referaty.sk/index.php?referat=3355