Human gut Targeted Locus (Loci)

Arginine flux during pregnancy is slower in Indian compared with American and Jamaican women and may contribute to the high prevalence of low birth weight babies in India. The gut is an important site of arginine and citrulline metabolism, and gut microbiota may affect gut function and dietary arginine metabolism. This study aimed to identify baseline differences in the gut microbiota of non-pregnant American, Indian, and Jamaican women as well as the relationship to gut permeability and citrulline and arginine metabolism. Citrulline and arginine fluxes, enteral arginine hydrolysis, and gut function were measured in the fasting and fed states in 30 American, Indian, and Jamaican women (n=10 per group). Fecal bacteria communities were characterized by 16S rRNA gene sequencing. Indian women had lower citrulline flux relative to American and Jamaican women in the fasting state and compared with American women in the fed state, and enteral arginine conversion to ornithine was higher in Indian women compared with American women in the fasting state. Indian women also had significantly impaired gut absorptive capacity compared with other women. Three dominant stool community types characterized by increased abundances of the genera Prevotella, Bacteroides, and Bacteroides with Clostridium were identified and reflected sample geographic origin. Indian women had increased relative abundances of Prevotella which were associated with diet, impaired intestinal absorptive capacity, and arginine flux. The combination of increased gut arginine metabolism, impaired absorptive capacity, and decreased citrulline flux in Indian women suggests decreased enterocyte mass.Increased understanding regarding the causes of low birth weight, particularly in developing countries such as India, is needed. Indian women have low production of the amino acid arginine, a compound that is necessary for the synthesis of new proteins, and this may lead to the development of low birth weight babies during pregnancy. Gastrointestinal bacteria are involved in digestion and may influence arginine availability to the body. In addition, the degree to which the gut absorbs arginine and produces and uses arginine within its cells may be important in determining arginine availability. The gut bacteria can be affected by environment and diet. The purpose of this study was to determine differences in gut bacteria in women from three geographic areas – America, India, and Jamaica – and their relationship to gut function as well as the production and utilization of arginine.