Gluconeogenesis yog tus txheej txheem ntawm kev sib xyaw kom qabzib hauv lub cev los ntawm cov chaw uas tsis yog carbohydrate xws li lactate thiab pyruvate. Nws yog qhov biosynthesis ntawm cov piam thaj tshiab, tsis yog los ntawm Gluconeogenesis tuaj yeem pom raws li qhov rov qab anabolic ntawm glycolysis, lub rhuav tshem thiab extraction ntawm lub zog ntawm qabzib.
Kev Noj Zaub Mov Qis thiab Cov Khoom Noj Tsawg (Low Carb Diet)
Tag nrho peb lub cev lub hlwb siv tau cov suab thaj, thiab ob peb yog nyob ntawm nws.
Yog tias koj haus tau cov khoom noj tsis zoo, koj lub cev muaj ntau hom qab zib los ntawm cov khoom noj khoom haus nruab nrab noj haus nruab nrab. Piv txwv, starches (plentiful hauv cov nplej xws li cov hmoov nplej, qos yaj ywm, thiab lwm yam) yog qhov ntev ntawm chains ntawm qabzib. Tsis tas li ntawd, ib txwm muaj cov suab thaj ntxiv xws li ntxiv suab thaj yog plentiful hauv cov zaub mov ntawm cov neeg feem coob. Txawm li cas los xij, yog tias tsis yog cov carbohydrate tsis noj, lub cev yuav ua kom qabzib los ntawm lwm qhov chaw. Txawm tias tus txheej txheem siv ntau lub zog thiab yog tus txheej txheem rov qab hais txog lub cev ua haujlwm li cas, gluceoneogenesis yog ua haujlwm rau koj lub cev metabolism kom tau thiab tuav lub zog uas nws xav tau kom ua rau lub cev tsis ua haujlwm.
Gluconeogenesis thiab koj lub siab
Cov txheej txheem ntawm gluconeogenesis yuav siv qhov chaw nyob hauv daim siab, qhov twg cov kua qab ntsev yog ua los ntawm cov amino acids (protein), glycerol (caj npab ntawm triglycerides , thawj rog roj molecule), thiab cov metabolism hauv qab zib xws li lactate thiab pyruvate.
Lactate yog tsim los ntawm kev sib tawg ntawm cov leeg nqaij thiab xa mus rau lub siab los ntawm cov hlab ntshav. Thaum hmo ntuj, thaum peb tsis tau noj li ob peb xuab moos, lub cev pib tsim cov glucose uas siv gluconeogenesis. Ntawm no yog qhov txheej txheem ua haujlwm li cas.
Peb Cov Kauj Ruam hauv Gluconeogenesis
- Kev hloov ntawm pyruvate rau phosphoenolpyruvic acid (PEP) yog thawj kauj ruam hauv gluconeogenesis. Muaj ob peb kauj ruam xav tau Los hloov pyruvate rau PEP nrog rau cov enzymes. Piv txwv, pyruvate carboxylase, PEP carboxykinase, thiab malate dehydrogenase yog lub luag haujlwm ntawm qhov kev hloov dua siab tshiab. Pyruvate carboxylase nyob ntawm mitochondria thiab hloov pyruvate mus rau hauv oxaloacetate. Oxaloacetate tsis tuaj yeem dhau los ntawm mitochondria daim nyias nyias, yog li nws yuav tsum tau hloov dua siab tshiab rau hauv malate los ntawm malate dehydrogenase. Malate tuaj yeem hla lub cim membrane mitochondria rau hauv cytoplasm qhov twg nws tau hloov dua siab tshiab rov qab mus rau hauv oxaloacetate nrog lwm malate dehydrogenase. Thaum kawg, oxaloacetate hloov dua siab tshiab hauv PEP ntawm PEP carboxykinase. Lwm cov kauj ruam tom ntej no yog tib yam nkaus li glycolysis xwb txheej txheem nyob nraud.
- Cov kauj ruam thib ob uas txawv ntawm glycolysis yog qhov hloov ntawm fructose-1,6-bP rau fructose-6-P nrog rau kev siv cov enzyme fructose-1,6-phosphatase. Kev hloov ntawm fructose-6-P rau qabzib-6-P siv tib lub enzyme li glycolysis, phosphoglucoisomerase.
- Cov kauj ruam dhau los uas txawv ntawm glycolysis yog hloov ntawm cov suab thaj-6-P rau cov ntshav qab zib nrog rau cov enzyme glucose-6-phosphatase. Qhov no enzyme nyob rau hauv qhov endoplasmic reticulum.
Qhov tseem ceeb ntawm cov suab thaj kom koj lub cev thiab koj lub paj hlwb
Ntshav yog qhov tseem ceeb ntawm lub zog rau lub cev thiab lub hlwb. Gluconeogenesis saib kuas tias thaum tsis muaj qabzib los ntawm glycolysis uas tseem ceeb ntawm cov kabmob tseemceeb yog khaws cia thaum carbohydrate tsis tuaj. Lub hlwb ib leeg siv li 100 gram glucose ib hnub twg. Lub cev yog ua tau sai siv cov piam thaj rau lub zog.
Qhov chaw:
Dietary Reference Intakes rau Energy, Carbohydrate, Fibre, Muaj roj, Acid Acids, Cholesterol, Protein, thiab Amino Acids (Macronutrients) (2005), Lub koom haum tshuaj, Khoom noj khoom haus thiab khoom noj khoom haus Board, National Academy of Sciences.
Kev Kho Mob Biochemistry Page.
UC Davis. Gluconeogenesis. ChemWiki 2016.