Ọ dị ezigbo mkpa ịghọta etu njikọta cholesterol n’ime imeju si eme. Ọ bụrụ n’inyocha okwu a n’ụzọ zuru ezu, ọ ga - amata ozugbo ihe njikọta imeju nwere njikọ a. Mana ibu ụzọ cheta na ihe ahụ nwekwara aha, nke a na-ejikarị ya, nke bụ cholesterol.
Dịka anyị kwuworo n’elu, ihe a bụ ihe mejupụtara ya na-ahụ ihe nile dị ndụ. Ọ bụ akụkụ dị mkpa nke lipids.
A na-ahụta nlebara anya kachasị elu na ngwaahịa sitere na anụmanụ. Ma na ngwaahịa osisi enwere naanị obere akụkụ nke onyinye a.
Ọ dịkwa mkpa ịmara eziokwu na yana nri naanị pasenti iri abụọ nke ngụkọta cholesterol na-abanye, pasent iri asatọ na-ahụ ahụ na-amịpụta onwe ha. Site n'ụzọ, n'ime ihe niile mejupụtara naanị ya, 50% mejupụtara na imeju ya. Nke a na-eme na ọkwa cellular, a na-emepụta 30% fọdụrụ n'ime eriri afọ na anụ ahụ.
Ahụ mmadụ nwere ọtụtụ ụdị nke ihe a. N'otu oge ahụ, ekwesịrị ịmara na ọ bụ usoro hematopoietic juputara n'ihe a. Cholesterol n'ime ọbara bụ akụkụ nke ogige mgbagwoju anya nke nwere protein, a na-akpọ ogige ndị a dị ka lipoproteins.
Mgbako nwere ike ịbụ ụdị abụọ:
- HDL - nwere nnukwu njupụta, a na-akpọ ha nke ọma;
- LDL - nwere ntakịrị nha, a na-akpọ ihe ndị a dị njọ.
Ọ bụ ụdị nke abụọ na-eburu mmadụ ọnwụ. Mgbe emechara ha, nke mejupụtara kristal nke ihe ahụ, ha na-amalite ịchịkọta n'ụdị iberibe n'ahụ mgbidi nke arịa ọbara, na-ebute mbufe ọbara. N'ihi ya, usoro a na - aghọ ihe na - ebute mmepe na ahụ nke ọrịa dị ka atherosclerosis.
Ọganihu nke atherosclerosis na-eduga na mmepe nke ọtụtụ ọrịa ndị siri ike.
Ihe njiri mara njikọ
Dịka e kwuru n’elu, ihe a nwere ike ịbara mmadụ uru, n’ezie, naanị ma ọ bụrụ na anyị na-ekwu maka HDL.
Dabere na nke a, ọ bịara doo anya na nkwupụta nke cholesterol na-emerụ ụmụ mmadụ kpamkpam bụ mmejọ.
Cholesterol ịbụ ihe dị ndụ na - arụ ọrụ:
- na-ekere òkè na njikọ nke homonụ mmekọahụ;
- ana achi achi aru oru ndi choro serotonin na ụbụrụ;
- bụ isi ihe dị na bile, yana vitamin D, nke bụ ọrụ maka ịnabata abụba;
- na - egbochi usoro mbibi nke ụlọ intracellular n'okpuru mmetụta nke radicals n'efu.
Mana yana ezigbo njiri mara, ihe nwere ike imerụ ahụike mmadụ. Dịka ọmụmaatụ, LDL nwere ike ibute mmepe nke ọrịa ndị siri ike, na-enye aka na mmepe nke atherosclerosis.
N'ime imeju, a na-agwakọta biocomponent n'okpuru mmetụta nke HMG redutase. Nke a bụ enzyme bụ isi metụtara biosynthesis. Ihe mgbochi nke njikọta sitere na mmetụta nke nzaghachi na-adịghị mma.
Usoro nchịkọta nke ihe na-emeju na imeju nwere mmekọrịta na-adịghị mma maka ogo nke onyinye na-abanye ahụ mmadụ na nri.
Ọbụna dị mfe, a kọwara usoro a n'ụzọ a. Imeju na-edozi ọkwa nke cholesterol. Ka mmadụ na-erikwu nri nke nwere ihe mejupụtara ya, a na-emepụta obere ihe na mkpụrụ ndụ nke ahụ, ma ọ bụrụ na anyị eburu n'uche na abụba na-erikọ nri na ngwaahịa ndị nwere ya, yabụ usoro nhazi a dị ezigbo mkpa.
Njirimara nke njikọta okwu
Ndị okenye nkịtị nwere ike na-agbakọta HDL na ọnụọgụ ruru 1 g / ụbọchị ma na-eri ihe dị ka 0.3 g / ụbọchị.
Ọkwa cholesterol dị n'ọbara mgbe niile nwere uru ahụ - 150-200 mg / dl. Ejidere ya kachasị site na ịchịkwa ọkwa nke njikọ dinetụ.
Ọ dị mkpa iburu n'obi na nchịkọta nke HDL na LDL nke endogenous sitere na usoro nri.
Cholesterol, sitere na nri ma mekwaa ya na imeju, ka etinyere membranes, na njikọ nke homonụ steroid na bile acid. A na-eji ihe kachasị ukwuu nke ihe ahụ eme ihe na njikọta nke bile acid.
Usoro ntinye nke HDL na LDL site na mkpụrụ ndụ ka ana - ejide n’aka nke ọma site na usoro atọ dị iche iche:
- Iwu nke HMGR Ọrụ
- Iwu nke cholesterol oke intracellular na-enweghị ihe ọ bụla site na ọrụ O-acyltransferase sterol, SOAT1 na SOAT2 na SOAT2, nke bụ akụrụngwa kacha arụ ọrụ na imeju. Ntinye aha mbụ nke enzyme ndị a bụ ACAT maka acyl-CoA: cholesterol acyltransferase. Enzymes ACAT, ACAT1, na ACAT2 bụ acetyltransferases 1 na 2 acetyl CoA.
- Site na ijikwa ọkwa plasma cholesterol site na LDL onye na-enweta mgbasa ozi na ebugharị HDL.
Iwu nke ọrụ HMGR bụ ụzọ bụ isi na-achịkwa ọkwa biosynthesis nke LDL na HDL.
Enzyme a nwere ụzọ anọ dị iche iche na-achịkwa:
- nzaghachi mgbochi nzaghachi;
- njikwa usoro igosipụta mkpụrụ ndụ;
- ọnụego enzyme;
- phosphorylation-dephosphorylation.
Usoro atọ ndị mbụ na-achịkwa na-eme ihe ozugbo na njiri ahụ. Cholesterol na - arụ ọrụ dịka nzaghachi nzaghachi na HMGR dịbu adị ma na - akpata mbibi ngwa ngwa nke enzyme ahụ. Nke ikpeazụ bụ nsonaazụ polyubiquitilation nke HMGR na mmebi ya na proteosome. Ikike a bụ nsonazụ nke ngalaba ikuku na-elebara anya nke HMGR SSD.
Na mgbakwunye, mgbe cholesterol riri nne, ọnụego mRNA maka HMGR na-ebelata n'ihi nkwụpụta sitere na usoro belatara.
Enzymes so na njikọ
Ọ bụrụ na a na-achịkwa mpaghara ihe dị na mgbanwe site na mgbanwe covalent, a ga - ebu usoro a n'ihi phosphorylation na dephosphorylation.
Enzyme ahụ na-arụkarị ọrụ n'ụdị na-akwadoghị. Phosphorylation nke enzyme na-ebelata ọrụ ya.
HMGR sitere na phosphorylated site na AMP na-arụ ọrụ protein kinase, AMPK. AMPK n'onwe ya na-eme ka phosphorylation rụọ ọrụ.
Enzymes abụọ na-ejikọ AMPK site na opekata mpe abụọ, ya bụ:
- Isi kinase nke na - eme ihe maka ịgbalite AMPK bụ LKB1 (imeju kinase B1). Ihe mbu LKB1 mere ka amata ya dị ka mkpụrụ ndụ ihe nketa n’ime ụmụ mmadụ na-ebu mmụpụta akpaghị aka na Putz-Jegers syndrome, PJS. Achọpụtakwara LKB1 ka ọ bụrụ na ọ na-emegharị ahụ na adenocarcinoma pulmonary.
- Ihe nke abụọ phosphorylating enzyme AMPK bụ proteinodini dabere protein kinase kinase beta (CaMKKβ). CaMKKβ na - ebute phosphorylation AMPK na nzaghachi na mmụba nke Ca2 + intracellular n'ihi mmetụ akwara.
Nhazi nke HMGR site na mgbanwe covalent na-enye ohere ịmepụta HDL. HMGR kacha rụọ ọrụ na steeti dephosphorylated. Phosphorylation (Ser872) enzyme protein protein nke AMP na-arụ ọrụ, bụ nke a na-ejikwa site na phosphorylation.
Phosphorylation nke AMPK nwere ike ime n'ihi opekata mpe abụọ.
- LKB1;
- CaMKKβ.
Dephosphorylation nke HMGR, weghachi ya na steeti dị ike karị, a na-arụ site na ọrụ protein phosphatases nke ezinụlọ 2A. Usoro a na - enyere gị aka ịchịkwa mmepụta nke HDL.
Kedu ihe na-emetụta ụdị cholesterol?
PP2A arụ ọrụ dị n'ụdị abụọ dị iche iche ejikọtara dịka PPP2CA na PPP2CB. Ihe abụọ dịpụrụ adịpụ nke PP2A bụ enzyme heterodimeric na heterotrimeric holoenzyme.
Isi enzyme PP2A nwere mejupụtara mkpụrụ osisi dị arọ (nke a na-akpọbu A subunit) yana subunit cat (nke dị n'okpuru ala). Egosipụta onyinye amara nke catalytic un PPP2CA site na mkpụrụ ndụ PPP2CB kpuchie ya.
Ejiri usoro PPP2R1A mechie ihe ntụhie ihu igwe ahụ site na mkpụrụ ndụ PPP2R1B. Isi enzyme ahụ, PP2A, na-arụkọ ọrụ na ngalaba nchịkwa na-agbanwe agbanwe iji chịkọta holoenzyme.
Ihe ntinye akara PP2A gụnyere ezinaụlọ anọ (nke akpọrọ B-subunits na mbụ), nke ọ bụla nwere ọtụtụ isoforms nke mkpụrụ ndụ dị iche iche tinyere.
Ugbu a, enwere mkpụrụ ndụ ihe dị iche iche iri na ise maka ntanetị nke PP2A B. Ọrụ bụ isi nke usoro nchịkwa nke PP2A bụ ịgbadobe mkpụrụ ndụ ndị na-enye ike na-arụ ọrụ phosphatase nke ọrụ prọfesọ PP2A.
PPP2R bụ otu n'ime usoro nchịkwa nchịkwa 15 dị iche iche nke PP2A. Hormones dịka glucagon na adrenaline na-emetụta cholesterol biosynthesis nke ukwuu site na ịbawanye ọrụ nke ngalaba nchịkwa usoro nke enzymes PP2A kpọmkwem.
PKA-onye gbara akwụkwọ na ntanetị nke PP2A (PPP2R) na - eduga na ntọhapụ nke PP2A na HMGR, na - egbochi dephosphorylation ya. Site na ibelata mmetụta glucagon na adrenaline, insulin na-akpali iwepụ phosphates ma si otú a na-abawanye ọrụ nke HMGR.
Iwu agbakwunyere nke HMGR pụtara site na mgbochi nke nzaghachi na cholesterol, yana iwu nke njikọ ya site na ịba ụba ọkwa cholesterol na sterol.
Ihe omume ikpeazu a jikọtara ya na SREBP transcription factor.
Kedụ ka usoro dị na ahụ mmadụ?
A na-enyocha ọrụ HMGR ọzọ site na ịdebanye aha na AMP. Mmụba na cAMP na-eduga n'ịrụ ọrụ nke protein protein dabere na cAMP, PKA. N'ihe banyere usoro iwu HMGR, PKA phosphory na-achịkwa ngalaba nchịkọta, nke na-eduga n'ịba ụba nke PP2A na HMGR. Nke a na - egbochi PP2A iwepu phosphates na HMGR, na - egbochi iweghachi ya.
Otu nnukwu ezinụlọ nke protein phosphatase subunits na-achịkwa ma ọ bụ gbochie ọrụ ọtụtụ phosphatases, gụnyere ndị otu PP1, PP2A, na ezinụlọ PP2C. Na mgbakwunye na phoPhates PP2A na-ewepụ phosphates na AMPK na HMGR, phosphatases nke protein phosphatase 2C ezinụlọ (PP2C) na-ewepụ phosphates na AMPK.
Mgbe usoro nchịkwa ndị a subunits phosphorylate PKA, ọrụ nke phosphatases agbatị na-ebelata, na-eme ka AMPK fọdụrụ na steeti phosphorylated na arụ ọrụ, na HMGR na steeti phosphorylated na-adịghị arụ ọrụ. Ka ewepụrụ mkpali ahụ, na-eduga n'ịba ụba na mmepụta CAMP, ọkwa phosphorylation na-ebelata, ọkwa dephosphorylation na-abawanye. Nsonaazụ njedebe bụ nlọghachi n'ọkwa dị elu nke ọrụ HMGR. N'aka nke ọzọ, insulin na-eduga n'ịbelata cAMP, nke, n'aka nke ya, na-eme ka njikọ ahụ rụọ ọrụ. Nsonaazụ njedebe bụ nlọghachi n'ọkwa dị elu nke ọrụ HMGR.
N'aka nke ọzọ, insulin na-eduga n'ịbelata cAMP, nke, n'aka nke ya, na-eme ka cholesterol na-arụ ọrụ. Nsonaazụ njedebe bụ nlọghachi n'ọkwa dị elu nke ọrụ HMGR. Insulin na-ebute mbelata nke cAMP, nke, n’aka nke ya, iji wee mee ka usoro ihe ndi ozo di ike.
Ikike iji kpalie insulin na igbochi glucagon, ọrụ HMGR kwekọrọ na mmetụta nke homonụ ndị a na usoro metabolic ndị ọzọ. Isi ọrụ nke homonụ abụọ ndị a bụ ịchịkwa nnweta na ibuga ike gị na sel niile.
Njikwa ogologo oge nke ọrụ HMGR na-arụkarị site na ịchịkwa njikọ na mmebi nke enzyme. Mgbe ọkwa cholesterol dị elu, ọkwa nke usoro ngosipụta nke HMGR na-agbada, ma na-atụgharị, ọkwa dị ala na-eme ka ngosipụta mkpụrụ ndụ dịkwuo elu.
Enyere ozi banyere cholesterol na vidiyo dị n'isiokwu a.
