Mannose da glucose, ko da yake suna da tsarin kwayoyin halitta iri ?aya (C ? H ?? O ?), duka aldoses ne kuma sune C-2 isomers (watau shugabanci na ?ungiyar hydroxyl akan carbon carbon na biyu ya bambanta), amma hanyoyin su na rayuwa da ayyukan physiological sun bambanta sosai. Mai zuwa yana ba da cikakken kwatancen bambance-bambancen metabolism na su daga mahalli da yawa:

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1. Shanyewar hanji

Glucose:

Ingantacciyar sha: SGLT1 (sodium glucose cotransporter 1) ke jigilar shi a cikin ?ananan ?wayoyin epithelial na hanji. Yawan sha yana da yawa sosai (>95%), wanda zai iya shiga cikin jini da sauri kuma yana ha?aka sukarin jini.

Ya dogara da sodium ion gradient. "

Mannose:

Rashin ingantaccen sha: galibi ta hanyar sau?a?e watsawa (yiwuwar ha?awa da jigilar dangin GLUT kamar GLUT5 ko tashoshi makamancin haka). Yawan sha yana da ?asa sosai (kimanin 10-20%), kuma yawancin mannose da ba a sha ba yana shiga cikin hanji kuma ana ha?e shi da ?wayoyin hanji ko kuma a fitar da shi da najasa.

2. Shiga cikin jini

Glucose:

Bayan sha, kai tsaye yana shiga cikin jijiyar tashar portal, yana haifar da saurin ha?aka matakan sukari na jini.

Mannose:

Adadin sha yana da ?asa, kuma yawan ?wayar mannose a cikin jini ya yi ?asa sosai (ha?in jini na al'ada na azumi yana kusan 50 μ mol/L, ?asa da 4-6 mmol/L na glucose). Gudanar da baki na mannose baya haifar da gagarumin canji a matakan sukari na jini.

3. Matakan farko na ?aukar nama da metabolism

Glucose:

Insulin dogara: tsokar tsoka da adipose nama na glucose yana dogara sosai akan siginar insulin (ta hanyar jigilar GLUT4).

Hexokinase/Glucokinase: Bayan shigar da sel, ana fitar da shi ta hanyar hexokinase (HK) (nauyin tsarin) ko glucokinase (GK) (hanta) zuwa glucose-6-phosphate (G6P). Wannan shi ne ainihin kwayar cutar ciwon sukari.

Mannose:

Bai dogara da insulin ba: ?aukar nama baya dogaro da insulin.

Mannokinase (MK): An fi samun phosphorylated da mannokinase a cikin hanta (tare da ?an ?aramin adadin a cikin sauran kyallen takarda kamar kodan) zuwa mannose-6-phosphate (Man-6-P). Wannan shine ma?alli mai ?ayyadaddun ?ayyadaddun ?ayyadaddun ?ayyadaddun ?imar mannose metabolism.

Phosphomannose isomerase (PMI): Man-6-P an canza zuwa fructose-6-phosphate (F6P) ta phosphomannose isomerase. F6P samfurin matsakaici ne na hanyar glycolysis.

4. Babban hanyoyin rayuwa

Glucose:

Glycolysis makamashi wadata: G6P na iya shiga hanyar glycolysis don samar da makamashi (ATP).

Glycogen synthesis: Ha?awa da ajiyar glycogen a cikin hanta da tsokoki.

Hanyar pentose phosphate: yana haifar da NADPH da ribose-5-phosphate (an yi amfani da su don rage biosynthesis da ha?in nucleotide).

Fat synthesis: Lokacin da wuce haddi ya kasance, an canza shi zuwa mai.

Mannose:

Juyawa zuwa tsaka-tsakin glycolytic: Bayan fassarar PMI zuwa F6P, zai iya shiga hanyar glycolytic (za'a iya canza sashi na ?arshe zuwa glucose ko gaba ?aya oxidized don samar da makamashi).

Glycosylation precursor: Babban aikinsa shine ya zama farkon rukunin sukari don ha?a sar?o?in sukari masu ala?a da N! Man-6-P za a iya ?ara canzawa zuwa GDP mannose a cikin vivo, yana aiki a matsayin mai ba da gudummawa kai tsaye na ragowar mannose a cikin glycoproteins da glycolipids.

Glycosylation: Mannose shine ma?alli mai mahimmanci na sarkar oligosaccharides a cikin furotin N-linked glycosylation gyare-gyare (kamar Man ? GlcNAc ?). Wannan tsari yana faruwa a cikin endoplasmic reticulum da Golgi apparatus, kuma yana da mahimmanci don nadawa sunadaran gina jiki, kwanciyar hankali, yanki, da aiki (kamar ?wayoyin cuta, masu kar?ar hormone, da ?wayoyin mannewar tantanin halitta).

Juyawa zuwa glucose/glycogen: Amfanin yana da ?asa ka?an, kuma wasu hanyoyin glycolysis na F6P masu juyawa suna haifar da G6P, wanda aka canza zuwa glucose ko glycogen, amma gudummawar tana da ka?an.

5. Tasiri kan glucose jini da insulin

Glucose:

Girman sukarin jini mai mahimmanci: shine babban tushen sukarin jini.

Tsananin ru?i na ?oyewar insulin: Kwayoyin beta na pancreatic kai tsaye suna jin karuwa a cikin sukarin jini kuma suna ?oye insulin.

Mannose:

Kusan baya shafar sukarin jini: yana ?aukar ?asa ka?an, yana daidaitawa ba tare da samar da glucose ba, kuma baya dogaro da insulin.

Ba mai kuzarin fitar insulin ba: rashin ingantattun siginonin motsa glucose na jini.

6. Babban bambance-bambance a cikin ayyukan ilimin lissafi

Glucose:

Aiki mai mahimmanci: Babban tushen makamashi mai sauri (musamman kwakwalwa, tsokoki, da jajayen ?wayoyin jini), kiyaye ciwon sukari homeostasis.

Mannose:

Aiki mai mahimmanci: Ma?alli mai mahimmanci don biosynthesis na glycosylation, yana goyan bayan tsari da aikin glycoproteins da glycolipids (ganewar kwayar halitta, siginar siginar, rigakafi, nadawa sunadaran, da dai sauransu).

Ayyuka na biyu: Hana kamuwa da cututtukan urinary fili (ta hanyar toshe mannewar ?wayoyin cuta).

7. Bambance-bambancen aikace-aikacen asibiti

Glucose:

Kariyar makamashi (jiko), maganin hypoglycemic, gwajin ha?uri na glucose.

Mannose:

Rigakafin kamuwa da cututtuka na urinary fili (wanda aka fi sani da Escherichia coli) da kuma kula da takamaiman cututtukan glycosylation na kwayoyin halitta (kamar rashi CDG Ib MPI).