Lactose digestion in humans: intestinal lactase appears to be constitutive whereas the colonic microbiome is adaptable

Ontogeny of intestinal safety factors: lactase capacities and lactose loads.

We measured intestinal safety factors (ratio of a physiological capacity to the load on it) for lactose digestion in developing rat pups. Specifically, we assessed the quantitative relationships between lactose load and the series capacities of lactase and the Na+-glucose cotransporter (SGLT-1). Both capacities increased significantly with age in suckling pups as a result of increasing intestin...

The pro-region of human intestinal lactase-phlorizin hydrolase is enzymatically inactive towards lactose.

The pro-region of intestinal lactase-phlorizin hydrolase (LPH alpha) has been proposed to be important for the correct folding of pro-LPH and mature LPH (LPH beta). In this communication, analysis of the catalytic function of the LPH alpha pro-region is presented. Expression of a cDNA encoding LPH alpha in COS-1 cells reveals a polypeptide that does not hydrolyse lactose. Likewise, no lactase a...

Lactose and lactase.

Lactose nutrition in lactase nonpersisters.

Lactose handling by the human gut by most people, beyond being breast-fed, has been considered a disorder rather than physiological. A non-human mammalian milk source is novel for the majority. During the first 6 months of life, when neonates and infants are best breast-fed, lactose along with other macronutrients, provides energy, but may have other functions as well. At birth, babies are endo...

Effect of lactase preparations in asymptomatic individuals with lactase deficiency--gastric digestion of lactose and breath hydrogen analysis.

We compared two lactase preparations derived from Aspergillus orizae (AOL) and Penicillinase multicolor (PML) for stability in the stomach and overall enzymatic activity in 10 asymptomatic subjects with lactase deficiency. The subjects were given 10,000 FCC units of either AOL or PML 30 min prior to or simultaneously with 300 ml of milk. Gastric juice was withdrawn through a nasogastric tube im...