Usoro nke mmepụta uric acid
Uric acid bụ otu n'ime ihe ndị na-emepụta metabolism purine n'ime mmadụ. A na-ekwukarị ihe a n'ihi na oke ọbara nwere ike ibute hyperuricemia ma mee ka gout na akụrụ kpụọ nkume. Agbanyeghị, uric acid abụghị naanị "ihe dị ize ndụ" - na ọkwa nkịtị, ọ bụ akụkụ nke usoro ahụ ji alụso ọrịa ọgụ ma na-arụkwa ọrụ dị ka antioxidant na plasma. Iji ghọta ihe kpatara ọkwa uric acid nwere ike iji mụbaa ma kpatara nsogbu, anyị kwesịrị ịghọta usoro e si emepụta ya: site na isi iyi nke purines, ụzọ mmebi, enzymes dị mkpa, na usoro mwepụ.
1. Purine dị ka ihe e ji emepụta uric acid
Mmepụta uric acid na-amalite site na purines. Purines bụ akụkụ nke nucleotides (adenine na guanine) dị na DNA na RNA. Purines sitere na isi mmalite abụọ:
1. Endogenous purine (site n'ime ahụ)
Ahụ́ na-eme ka mkpụrụ ndụ dị ọhụrụ mgbe niile. Mgbe mkpụrụ ndụ nwụrụ ma gbajie ihe ndị dị na mkpụrụ ndụ ahụ, a na-emegharị ma ọ bụ gbajie nucleotides nke DNA/RNA. Usoro mmebi a na-emepụta purines efu, nke enwere ike ịgbanwe ka ọ bụrụ uric acid.
2. Purine sitere na mpụga (site na nri/ihe ọṅụṅụ)
Nri ndị nwere purine dị elu—dịka anụ akụkụ ahụ, ụdị nri mmiri ụfọdụ, ụfọdụ anụ uhie, ofe e tinyere n'ime mmiri, na ụfọdụ ngwaahịa e ji eme achịcha—nwere ike ime ka ibu purine dịkwuo elu. Ihe ọṅụṅụ na-aba n'anya na ihe ọṅụṅụ nwere nnukwu fructose na-enyekwa aka, ọ bụghị n'ihi na ha nwere ọtụtụ purine n'onwe ha, kama n'ihi na ha nwere ike ịkpalite mmepụta uric acid ma gbochie mwepụ ya.
Ọ bụ ezie na iri nri na-akpata nsogbu, n'ọtụtụ ọnọdụ, mmụba nke uric acid na-abụkarị n'ihi mmepụta endogenous na karịsịa mmebi nke mwepụta site na akụrụ.
2. Nchịkọta zuru oke nke metabolism purine
Purines sitere na mmebi nke nucleotides na-agafe ọtụtụ usoro biochemical. N'ụzọ dị mkpirikpi, ụzọ ahụ bụ dịka ndị a:
– Nucleotide (AMP/GMP) → nucleoside (adenosine/guanosine) → purine base (adenine/guanine)
– A na-agbanwe Adenine na guanine ka ha bụrụ ihe ndị dị n'etiti nke na-eduga na hypoxanthine na xanthine.
- A na-eme ka xanthine na hypoxanthine dịghachi ka uric acid
N'ime ụmụ mmadụ, uric acid bụ "ihe ikpeazụ" n'ihi na ụmụ mmadụ enweghị enzyme uricase (urate oxidase), nke na-agbanwe uric acid ka ọ bụrụ allantoin nke na-agbaze nke ọma. Enweghị uric acid a na-eme ka ụmụ mmadụ nwee ike ịnweta kristal uric acid mgbe ọkwa ya dị elu.
3. Usoro nhazi uric acid n'ụzọ zuru ezu
a) Njehie Nucleotide: site na AMP na GMP
A na-ahụ purine n'ọtụtụ n'ụdị nucleotides: AMP (adenosine monophosphate) na GMP (guanosine monophosphate). Mgbe mkpụrụ ndụ mebiri ma ọ bụ dochie ha, nucleotides ndị a na-agbaji.
– Enwere ike ịgbanwe AMP ka ọ bụrụ adenosine, wee bụrụ inosine. A na-ekewa Inosine ka ọ bụrụ hypoxanthine.
– A na-agbanwe GMP ka ọ bụrụ guanosine, wee bụrụ guanine, nke a na-agbanwe ka ọ bụrụ xanthine.
N'oge a, ọtụtụ ụzọ nwere ike ịgafe. Nsonaazụ ikpeazụ na-ejikọtakarị na molekul abụọ dị mkpa: hypoxanthine na xanthine.
b) Ọrụ nke enzyme xanthine oxidoreductase (XOR)
Isi ihe dị mkpa n'ịmepụta uric acid bụ oxidation nke hypoxanthine na xanthine. Otu enzymes a na-akpọkarị xanthine oxidoreductases na-akpali usoro a, nke nwere ike ịdị n'ụdị abụọ:
- Xanthine dehydrogenase (XDH)
– Xanthine oxidase (XO)
Mmeghachi omume ndị na-esochi usoro nke na-eme:
1. Hypoxanthine → Xanthine
2. Xanthine → Uric acid
N'ọnọdụ ụfọdụ (dịka nrụgide oxidative ma ọ bụ mbufụt), ụdị XO na-akawanye njọ ma nwee ike ịmepụta radicals free (ụdị oxygen reactive). Nke a bụ otu ihe kpatara hyperuricemia ji ejikọta ya na usoro mkpali na nsogbu metabolic mgbe ụfọdụ.
c) Ụzọ "Salvage": imegharị ihe nke purine nke na-egbochi mmepụta uric acid
Ọ bụghị purine niile ka a na-akpọ uric acid. Ahụ nwere usoro "na-azọpụta" a na-akpọ purine salvage pathway, nke na-emegharị ntọala purine ka ọ bụrụ nucleotides. Enzymes dị mkpa n'ụzọ a gụnyere:
– HGPRT (hypoxanthine-guanine phosphoribosyltransferase): na-emegharị hypoxanthine na guanine.
– APRT (adenine phosphoribosyltransferase): na-emegharị adenine.
Ọ bụrụ na ụzọ mgbapụta ahụ na-arụ ọrụ nke ọma, a na-emegharị ọtụtụ purines, na-ebelata mmepụta uric acid. N'aka nke ọzọ, ọ bụrụ na e nwee nsogbu (dịka enweghị HGPRT n'ọnọdụ mkpụrụ ndụ ihe nketa ụfọdụ), ọtụtụ purines na-abanye n'ụzọ mmebi nke uric acid, na-amụba ọkwa ya.
4. Gịnị mere ọkwa uric acid ji amụba?
N'ụzọ usoro, a na-ekpebi ọkwa uric acid dị n'ọbara site na nguzozi dị n'etiti mmepụta na mwepụta.
a) Mmepụta na-abawanye
Mmepụta uric acid na-abawanye mgbe:
- Ịṅụ purine dị elu mgbe niile.
– Nnukwu mmebi mkpụrụ ndụ na-eme (dịka ọmụmaatụ n'ọnọdụ ụfọdụ nke na-eme ka mgbanwe mkpụrụ ndụ dịkwuo elu).
– Ụfọdụ metabolism ike na-eme ka mmepụta nke purines na mmebi ha dịkwuo elu.
– Ịṅụ mmanya nwere ike ime ka mmepụta lactate dịkwuo elu ma gbanwee metabolism ka urate wee mụbaa.
- Fructose nwere ike ime ka mmebi nke ATP dị n'ime imeju dịkwuo elu, na-emepụta ihe ndị na-ebute ụzọ nke purine nke na-eme ka uric acid dịkwuo elu.
b) Mbelata mwepụ nke ihe (ihe a na-ahụkarị n'ọrụ ahụike)
A na-esi n'akwara akụrụ wepụta ọtụtụ uric acid, ebe ihe fọdụrụ na-esi n'ime eriri afọ apụta. N'ime akụrụ, uric acid na-eme usoro ndị a:
1. Nzacha na glomerulus
2. Mweghachi n'ime tubule proximal
3. Mmịpụta azụ n'ime tubule
4. Mweghachi akụkụ nke mmiri
Nke a pụtara na nhazi uric acid n'ime akụrụ na-agbanwe agbanwe nke ukwuu. Ọrụ akụrụ na-adịghị mma, akpịrị ịkpọ nkụ, iguzogide insulin, ma ọ bụ ụfọdụ ọgwụ nwere ike ibelata mmịpụta uric, nke na-eduga n'ọbara na-abawanye.
5. Site na uric acid ruo kristal: mmalite nke nsogbu gout
Uric acid na-agbaze n'ọbara ruo n'ókè ụfọdụ. Mgbe ọkwa ya gafere oke ịgbaze, karịsịa n'okpomọkụ dị ala (dịka ọmụmaatụ, na nkwonkwo dị n'akụkụ dịka mkpịsị ụkwụ ukwu), uric acid nwere ike ịmepụta kristal monosodium urate. Sistemụ ahụ ji alụso ọrịa ọgụ na-amata kristal ndị a dị ka "ihe dị ize ndụ," na-akpata nnukwu mbufụt, ihe mgbu, ọbara ọbara, na ọzịza nke njirimara nke mwakpo gout.
E wezụga na nkwonkwo, ihe ndị na-abanye n'ime akụrụ nwekwara ike ime, nke na-eme ka ohere nke nkume uric acid dịkwuo elu.
6. Ihe ndị na-emetụta usoro mmepụta uric acid
Ụfọdụ ihe nwere ike ime ka usoro maka mmepụta na ọkwa uric acid dị elu gụnyere:
– Mkpụrụ ndụ ihe nketa: mgbanwe dị na mkpụrụ ndụ ihe nketa nke na-ebuga urate na enzymes nke akụrụ ma ọ bụ purine metabolism.
– Nri: ọtụtụ purines, mmanya na-aba n'anya, ihe ọṅụṅụ dị ụtọ nke fructose dị elu.
– Ọnọdụ mmiri mmiri: enweghị mmanya na-eme ka mmamịrị na-amịkọrọ ma na-ebelata mmịpụta uric.
– Ibu ahụ na iguzogide insulin: ejikọtara ya na mbelata mwepụta urate.
– Ọrụ akụrụ: ka ọrụ akụrụ na-ebelata, otú ahụ ka ohere nke hyperuricemia na-abawanye.
– Ọgwụ ụfọdụ: ụfọdụ ọgwụ nwere ike ibelata mmịpụta urate ma ọ bụ metụta metabolism.
7. Mmechi
Usoro nke mmepụta uric acid n'ime mmadụ bụ nsonaazụ ikpeazụ nke metabolism purine, ọkachasị site na ụzọ mbibi nke gụnyere hypoxanthine, xanthine, na enzyme xanthine oxidoreductase, na-ebute mmepụta uric acid. Ahụ nwere ụzọ recycle purine (salvage) nke nwere ike igbochi mmepụta uric acid, mana nguzozi ka na-emetụta nke ukwuu site na oriri, mgbanwe mkpụrụ ndụ, na ikike akụrụ nwere iwepụ urate. Mgbe mmepụta na-abawanye ma ọ bụ na-ebelata mwepụta, ọkwa uric acid nwere ike gafere oke mgbaze ma kpalite mmiri ozuzo kristal, na-eduga na gout ma ọ bụ nkume akụrụ. Site n'ịghọta usoro ahụ, mgbochi na njikwa ọkwa uric acid nwere ike ibute ihe mgbaru ọsọ karịa - site na nri, ụdị ndụ, na ụzọ ahụike, ọ bụrụ na ọ dị mkpa.
