Mechanisms by which gut microorganisms influence food sensitivities

Central and peripheral mechanisms by which ghrelin regulates gut motility.

Ghrelin is the recently discovered endogenous ligand for the growth hormone secretagogue receptor. This receptor had previously been characterized based on the stimulatory effect of synthetic peptides, enkephalin analogues, on growth hormone secretion by pituitary somatotrophs. Surprisingly, ghrelin is most abundant in the stomach, suggesting that it may have effects beyond the stimulation of g...

Food-derived bioactive peptides influence gut function.

Bioactive peptides either present in foods or released from food proteins during digestion have a wide range of physiological effects, including on gut function. Many of the bioactive peptides characterized to date that influence gut motility, secretion, and absorption are opioid agonists or antagonists. The authors review a body of experimental evidence that demonstrates an effect of peptides ...

Food allergies and sensitivities.

Food allergies and other food sensitivities.

Some people experience individual adverse reactions to foods that most other people can eat with no ill effects. These food sensitivities include true food allergy, involving the body's immune system, and various types of nonallergic food sensitivities.

Mechanisms of steroid oxidation by microorganisms.

Two enzymes are responsible for the cleavage of pregnane side chains. A steroid-inducible oxygenase, in the presence of reduced nicotinamide adenine trinucleotide and molecular oxygen, catalyzes the conversion of progesterone into testosterone acetate. The latter ester is then hydrolyzed by an esterase to yield testosterone. The oxygenase has been partially purified and separated from the ester...