Gluconeogenesis in dairy cows: The secret of making sweet milk from sour dough

@article{Aschenbach2010GluconeogenesisID,
  title={Gluconeogenesis in dairy cows: The secret of making sweet milk from sour dough},
  author={J{\"o}rg R. Aschenbach and Niels Bastian Kristensen and Shawn S. Donkin and Harald Michael Hammon and Gregory B Penner},
  journal={IUBMB Life},
  year={2010},
  volume={62}
}
Gluconeogenesis is a crucial process to support glucose homeostasis when nutritional supply with glucose is insufficient. Because ingested carbohydrates are efficiently fermented to short‐chain fatty acids in the rumen, ruminants are required to meet the largest part of their glucose demand by de novo genesis after weaning. The qualitative difference to nonruminant species is that propionate originating from ruminal metabolism is the major substrate for gluconeogenesis. Disposal of propionate… 

Control of Hepatic Gluconeogenesis During the Transition Period

The importance of gluconeogenesis, a metabolic pathway that results in formation of glucose from non-carbohydrate carbon substrates, is underscored in dairy cattle by to the lack of intestinal

Short communication: Regulation of hepatic gluconeogenic enzymes by dietary glycerol in transition dairy cows.

The observed increase in PEPCK-C expression with glycerol feeding may indicate regulation of hepatic gene expression by changes in rumen propionate production and suggests that dietary energy source alters hepatic expression.

Propionate induces gluconeogenesis in dairy cattle through direct activation of the bovine cytosolic phosphoenolpyruvate carboxykinase gene promoter

The central hypothesis of this dissertation is that propionate regulates its own metabolism in liver of dairy cattle through regulation of the PCK1 gene, a critical reaction for gluconeogenesis.

Effect of propionate on mRNA expression of key genes for gluconeogenesis in liver of dairy cattle.

Data indicate a tendency for in vivo effects of propionate to alter hepatic gene expression in mid-lactation cows and neonatal calves, which is consistent with a feed-forward effect of propIONate to regulate its own metabolism toward gluconeogenesis through changes in hepatic PCK1 mRNA.

Histidine Promotes the Glucose Synthesis through Activation of the Gluconeogenic Pathway in Bovine Hepatocytes

It is demonstrated that bovine hepatocytes can efficiently convert His into glucose to provide the energy required and indicate that the addition of His may be efficiently converted into glucose via the upregulation of genes related to the gluconeogenic pathway.

Increased anaplerosis, TCA cycling, and oxidative phosphorylation in the liver of dairy cows with intensive body fat mobilization during early lactation.

Data indicate that increasing lipolysis leads to augmenting nutrient catabolism for anaplerosis and mitochondrial respiration, providing a molecular link between hepatic oxidative processes and feed intake.

Precursors for liver gluconeogenesis in periparturient dairy cows.

Combining data from quantitative and qualitative experimental techniques on L-lactate metabolism point to the conclusion that the quantitatively most important adaptation of metabolism to support the increased glucose demand in the immediate post partum period is endogenous recycling of glucogenic carbon through lactate.

Hepatic pyruvate carboxylase expression differed prior to hyperketonemia onset in transition dairy cows

It is demonstrated that HYK cows experience a decrease in the ratio of hepatic PC to PCK at 1 day postpartum prior to HYK diagnosis which, on average, manifested a week later.

Metabolic Hydrogen Flows in Rumen Fermentation: Principles and Possibilities of Interventions

  • E. Ungerfeld
  • Chemistry, Medicine
    Frontiers in Microbiology
  • 2020
A basic kinetic model of competition for dihydrogen is presented, and possibilities for intervention to redirect metabolic hydrogen from methanogenesis toward alternative useful electron sinks are discussed.
...

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...