Kedu ka njikọta cholesterol n'ime imeju?

Ebe ọ bụ na ihe ahụ bụ nke otu ndị ahoụrụma, okwu ahụ bụ “cholesterol” bụ naanị ihe dị mma, ebe aha “cholesterol” (n'ụzọ nkịtị “ike nke bile” n'ihi mbịne ya na mbụ nke gallstones)) bụ nke emebere - site n'aka ọdịnala - nke mbụ onye French chemist Pouletier de La Sal, o gosipụtara njiri mara nke abụba dị iche iche, nke edoburu ya na mbụ.

N'ihi ụfọdụ akọ na uche nke ndị sayensị, cholesterol ekwuputara "onye iro Nke 1" maka ahụike ahụ ọtụtụ afọ, nke kpatara ezigbo mgbanwe na ụlọ ọrụ nri, ọgwụ na usoro ọgwụgwọ - yana ngwaahịa ndị nwere obere abụba, ọgwụ ọhụrụ na ụzọ pụtara na ụwa nke nwere ike belata mkpocha ahụ. ogige n'ime ọbara, yana ihe ndị a niile - yana ngwaọrụ nchịkwa maka "pesti" ka enwere ike idobe ya mgbe niile.

Ebe ọ bụ na ụzọ kachasị mma iji chọpụta ihe ọjọọ nke otu ma ọ bụ ihe ọzọ bụ usoro iji wepụ ya na mgbasa, a emeela ya - n'ihi nke a, ụwa niile na-aghọrọ mkpụrụ ọjọọ nke "nri na-emebi emebi", ndị sayensị na-amanye mgbaghara ma kwe nkwa idozi ya. Ma enwere ike ime nke a naanị ma ọ bụrụ na ịghọta mmalite na ezigbo ọrụ ihe dị na ahụ.

Isi ọrụ nke cholesterol

Na mgbakwunye na eziokwu na ọ bụ ihe dị mkpa (ihe na-eme ka ihe kwụsie ike) nke cytoplasmic membrane, na-agba mbọ na njiri ike nke okpukpu abụọ ya n'ihi ụmụ irighiri ihe ndị ọzọ dị na mkpụrụ ndụ pholesthorol, cholesterol na-egosipụta onwe ya dị ka onye na - akpata nhazi nke mgbidi sel, na - egbochi mgbochi hemolysis na-eme ka ọnụego ya .

Ọ na - arụ ọrụ dị ka ihe mbido maka mmepụta nke ogige ndị steroid:

• homonụ corticosteroid;
• homonụ mmekọahụ;
• bile acid;
• Vitamin D-otu (ergocalciferorol na cholecalciferol).

Nyere mkpa ọ dị otu a n’ime ihe eji eme ihe, ọ ga - apụta ihe mmerụ nke nri cholesterol na-adịghị ma ọ bụ mbelata nke anụ ahụ na ọkwa nke ihe a n’ime ọbara.

N'ihi insolubtersent ya na mmiri, enwere ike ibute ihe a site na ọbara naanị yana njikọ ya na protein nke ebufe (apolipoproteins), mgbe ejikọtara ya na usoro etolite nke lipoprotein.

N'ihi ịdị adị nke ọtụtụ apolipoproteins dị iche iche (nke nwere ọdịiche dị na ịdị arọ nke molekul, ogo tropism ha maka cholesterol, na kwa n'ihi ikike nke mgbagwoju anya ịgwakọta n'ọbara, na akụrụngwa na-adịghị mma nke kristal cholesterol iji mepụta atherosclerotic plaques), a na-amata ụdị Lipoproteins ndị a:

• njupụta dị elu (HDL, ma ọ bụ nnukwu molikula olu, ma ọ bụ HDL-lipoproteins);
• Ogologo nju (LDL, ma obu obere molikula, ma obu LDL-lipoproteins);
• njupụta dị oke ala (VLDL, oke molekul dị ala, ma ọ bụ VLDL nke lipoproteins);
• chylomicrons.

Ka anụ ahụ dị, cholesterol na-abanye na chylomicrons, LDL ma ọ bụ VLDL, na umeji (yana iwepụ anụ ahụ na - esote) - site na ibugharị apolipoproteins nke ụdị HDL.

Atụmatụ njikọ

Iji mee ka epeepe abụọ nke atherosclerotic mepụta site na cholesterol (nke na-abụ n'otu oge "patịles" na mgbidi akwara ozi mebiri emebi, yana "oghere" dị na mpaghara ebe na-enweghị atrophy nke akwara nke uru ahụ kwesịrị iduga na mgbapụ ya - saịtị ahụ dara), ma ọ bụ homonụ, ma ọ bụ ngwaahịa ndị ọzọ, a ga-ebu ụzọ rụọ ya n'otu n'ime ụzọ atọ:

• anụ ahụ
• eriri afọ;
• imeju.

Ebe ọ bụ na mkpụrụ ndụ akwara (cytosol na ezigbo endoplasmic reticulum) bụ ndị bụ isi ihe na - eweta ya (na 50% ma ọ bụ karịa), ekwesịrị ịtụle njikọ nke ihe ahụ kpọmkwem site n'ọnọdụ nke mmeghachi omume dị na ya.

Ngwakọta nke cholesterol na - aputa na ọkwa ise - na usoro nhazi usoro:

• mevalonate;
• dịpụrụ adịpụ pyrophosphate;
• squalene;
• lanosterol;
• n'ezie cholesterol.

A ga - ekwe omume na - emegharị mgbanwe agaghị enwe ike na - enweghị ike itinye aka na ndị enzymes.

Video on cholesterol synthesis:

Enzymes na-ekere na nguzobe nke okwu

Na nmalite izizi (nke mejuputara oru ato), ihe ndi ac acacacacion CoA (coenzyme A) bu ihe acetyl-CoA-acetyltrasferase (thiolase) site na mmekorita nke umu acetyl-CoA abuo. Ọzọkwa, site na ntinye aka nke HMG-CoA synthase (hydroxymethyl-glutaryl-CoA synthase), njikọ sitere na acetoacetyl-CoA na molecule nke acetyl-CoA ꞵ-hydroxy-ꞵ-methylglutaryl-CoA ga-ekwe omume.

Na mbelata nke HMG (ꞵ-hydroxy-ꞵ-methyl-glutaryl-CoA) site na ikpochapụ nke HS-CoA iberibe na ntinye nke NADP-based hydroxymethyl-glutaryl-CoA reductase (HMG-CoA reductase), ngwaahịa mbụ na-agbasa, ihe cholesterol preursor bụ melon, meva melon). )

Na ọkwa nke njikọ isoachinyl pyrophosphate, a na-arụ ọrụ anọ. Site na mevalonate kinase (ma phosphomevalonate kinase), a na-atụgharị Mevalonate na 5-phosphomevalonate na 1 na 2 Mevalonate kinase (na phosphomevalonate kinase), na nke ọzọ gaa na 5-pyrophosphomevalonate, nke na-aghọ 3-phospho-5-pyrophosphomevalonate na 3lation at 3 (yana ntinye nke enzyme kinase).

Ọrụ ikpeazụ bụ decarboxylation na dephosphorylation na usoro nke isoachinyl pyrophosphate (ebido na ntinye nke enzyme pyrophosphomevalonate decarboxylase).

Na njikọ nke squalene, a malitere isomerization nke isopentenyl pyrophosphate ka dimethylallyl pyrophosphate pụtara (n'okpuru mmetụta isopentyl phosphatisomerase), mgbe ahụ isoachenyl pyrophosphate na-echekwa pyrophosphate (njikọta electronic na-adị n'etiti C₅ mbụ na C₅ ihe ozo) na nguzo geranyl pyrophosphate (ma nwekwaa moro nke pyrophosphate).

Nzọụkwụ na-esote, njikọta n’etiti C₅ isopentenyl pyrophosphate na C₁₀ geranyl pyrophosphate - n'ihi nnabata nke mbụ ya na nke abụọ, etolitewo farnesyl pyrophosphate na molecule pyrophosphate nke ọzọ na-ekpochapu na C₁₅.

Oge a kwụsịrị na oghere nke ụmụ irighiri parnesyl pyrophosphate abụọ na mpaghara C₁₅- C₁₅ (na isi isi) site na iwepu molikula pyrophosphate abụọ n'otu oge. Maka oghere nke molekul abụọ, a na-eji mpaghara pyrophosphate dị iche iche, otu n'ime ha ga - emecha nke ọma, nke na - eduga n'ịmepụta pyrophosphate. Mgbe NADPH belatara (na mwepụ nke abụọ nke pyrophosphate), ihe a dị n'etiti (n'okpuru mmetụta nke squalene synthase) na-agbanwe n'ime skavalen.

Na njikọ nke lanosterol enwere arụmọrụ abụọ: nke mbụ gwụsịrị na ịmepụta squalene epoxide (n'okpuru mmetụta nke squalene epoxidase), nke abụọ - ya na cyclization nke squalene epoxide banye na ngwaahịa ikpeazụ nke ogbo - lanosterol. Akpagharị otu methyl site na C₁₄ na C₁₃, na C₈ na C₁₄ maara oxidosqualene-lanosterol cyclase.

Agba nke ikpeazụ nke mkpara gụnyere usoro nke arụmọrụ ise. N'ihi nsị nke anwụrụ C₁₄ Otu methyl nke lanosterol na - emepụta ihe ana - akpọ 14-desmethylanosterol. Mgbe mwepu nke abụọ methyl ọzọ (na C₄) ihe ahụ na-aghọ zymosterol, n'ihi nsonaazụ nke njikọ nke abụọ C₈= C₉ iji ọnọdụ C₈= C₇ nguzosi nke δ-7,24-cholestadienol na aputa ihe (n ’ime ihe isomerase).

Mgbe ịghafere njikọkọ abụọ C₇= C₈ iji ọnọdụ C₅= C₆ (site na ibụ nke deslesterol) na mweghachi nke njikọta abụọ na yinye, a na-emepụta ihe nke ikpeazụ - cholesterol (ma ọ bụ kama nke ahụ, cholesterol). Enzyme “δ” 24-reductase “na-eduzi” ọkwa ikpeazụ nke cholesterol synthesis.

Kedu ihe na-emetụta ụdị cholesterol?

N’iji ike dị ala nke lipoproteins molecule dị ala (LDL), ebumnuche ha maka ịkpalite kristal cholesterol (site na ịmalite ịkpụkpọ atherosclerosis na akwara ndị na-eme ka ohere nke obi na akwara ike), lipoproteins nke ụdị a na-akpọkarị "ajọ kọlesterol", ebe lipoproteins dị elu na Akpukpo moliles (HDL) nke nwere ihe ozo di iche (n’enweghi nsogbu nke atherogenicity) ka akporo cholesterol “bara uru.”

N'iburu n'uche mmeghachi omume nke usoro a (anụ ahụ enweghị ike ịbụ ihe ọ bụla na-abaghị uru ọ bụla ma ọ bụ na-enweghị mmerụ ahụ), n'agbanyeghị nke ahụ, a na-atụ aro ugbu a maka ndị nwere nnukwu ohere maka ọrịa vaskụla iji chịkwaa ma belata LDL n'ọkwa kachasị mma.

N'ihe kariri 4.138 mmol / l, a na-atụ aro ịhọrọ nri iji belata ọkwa ha na 3.362 (ma ọ bụ obere), ọkwa dị elu karịa 4.914 bụ ihe ngosipụta maka ịkọwa ọgwụ iji belata ọgwụ ị artifụ ọgwụ.

Ọ bụ ihe ndị mejupụtara akụkụ ọbara ọbara nke "ajọ cholesterol"

• arụ ahụ dị ala (arụ ọrụ nkịtị);
• ịreatụbiga nri ókè (ịdabere na nri), yana nsonaazụ ya - oke ibu ma ọ bụ oke ibu;
• ihe oriri na - eme ka ihe ghara ịdị mma - yana abụba nke trans abụba, carbohydrates dị omimi ngwa ngwa (Grafica, muffins) na mmebi nke ọdịnaya nke pectin, eriri, vitamin, Chọpụta akụkụ, abụba nke polyunsaturated mejupụtara;
• ọnụnọ nke ọgwụ egbu egbu nke ezinụlọ (ị smokingụ sịga, ị alcoholụ mmanya na-aba n'anya n'ụdị mmanya dị iche iche, ị abuseụ ọgwụ ọjọọ).

Ọnụnọ ọnụnọ ọrịa somatic na-adịghị ala ala na-enwekwa otu mmetụta siri ike:

• ọrịa ọnya;
• nsogbu endocrine na hyperproduction nke homonụ nke adrenal cortex, ụkọ nke thyroid ma ọ bụ homonụ mmekọahụ, ma ọ bụ ọrịa shuga mellitus;
• gbasara akwara na oke ịba ọcha n'anya nke nsogbu ụfọdụ nke njikọta akwara 'Lipoproteins' bara uru nke na-apụta na akwara ndị a;
• ọrịa dyslipoproteinemia.

Ọnọdụ cholesterol metabolism na-adabere kpọmkwem na steeti microflora nke eriri afọ, nke na-akwalite (ma ọ bụ gbochie) abụba nke abụba nri, yana esonye na njikọ, mgbanwe, ma ọ bụ mbibi sterol nke exogenous ma ọ bụ nkwụghachi.

Nke ozo, ime ka ihe choputa cholesterol “ihe jọrọ njọ”:

• mmụta mmụta anụ ahụ, egwuregwu, ịgba egwu;
• ịnọgide na-ebi ndụ dị mma n’enweghị anwụrụ na mmanya;
• nri dị mma n’enweghi ike carbohydrates dị mfe mmiri, nke nwere obere anụ nke abụba anụmanụ zuru oke - mana nwere afọ ojuju zuru ezu nke faiba, polyunsaturated fatty acids, ihe ndị na - eme ka mmiri (lecithin, methionine, choline), ihe ndị metụtara, vitamin.

Vidiyo site na ọkachamara ahụ:

Kedụ ka usoro dị na ahụ?

Naanị ihe dị ka 20% nke cholesterol na - abanye n'ime ahụ na nri a riri - ọ na - ekepụta 80% fọdụrụnụ site na ya, na mgbakwunye na imeju, a na - eme usoro njikọ ahụ site na ezigbo endoplasmic reticulum sel.

• eriri afọ;
• gren adrenal;
• akụrụ
• gril gital.

Na mgbakwunye na usoro oge gboo maka ịmepụta klọọkụ cholesterol nke akọwapụtara n’elu, enwere ike iji ya mee ihe na-abụghị mevalonate. Yabụ, otu n'ime nhọrọ bụ ịmepụta otu ihe si na glucose (nke na-esite na enzymes ndị ọzọ na n'okpuru ọnọdụ ndị ọzọ nke akụkụ ahụ).