Impact of Formate Supplementation on Body Weight and Plasma Amino Acids

Abstract

Current nutritional recommendations are focused on energy, fat, carbohydrate, protein and vitamins. Less attention has been paid to the nutritional demand of one-carbon units for nucleotide and methionine synthesis. Here, we investigated the impact of sodium formate supplementation as a nutritional intervention to increase the dietary intake of one-carbon units. A cohort of six female and six male mice received 125 mM of sodium formate in the drinking water for three months. A control group of another six female and six male mice was also followed up for the same period of time. Tail vein blood samples were collected once a month and profiled with a haematology analyser. At the end of the study, blood and tissues were collected for metabolomics analysis and immune cell profiling. Formate supplementation had no significant physiological effect on male mice, except for a small decrease in body weight. Formate supplementation had no significant effect on the immune cell counts during the intervention or at the end of the study in either gender. In female mice, however, the body weight and spleen wet weight were significantly increased by formate supplementation, while the blood plasma levels of amino acids were decreased. Formate supplementation also increased the frequency of bifidobacteria, a probiotic bacterium, in the stools of female mice. We conclude that formate supplementation induces physiological changes in a gender-specific manner.

Short-chain fatty acids promote the effect of environmental signals on the gut microbiome and metabolome in mice

“…The stability of SCFA solution kept at RT for 7 days was verified by NMR analysis. The SCFA concentrations used were similar to those used in previous papers 18 , 60 , 69 , 76 , 77 and shown not to be toxic in mice. Sodium matched SE groups were used in all the experiments with SCFAs.…”

The gut microbial metabolite formate exacerbates colorectal cancer progression

“…Here, 11–15-week-old germ-free in-house-bred C57BL/6Ntac mice ( M. musculus ) received a single 10 mg kg −1 intraperitoneal azoxymethane (AOM) injection (A5486, Sigma-Aldrich). Three days later, male and female mice received 10 8 colony forming units (CFU) Fn suspended in 200 µl of PBS via by oral gavage (PBS alone as control) or formate (250 mM) was provided in the drinking water (male mice only) for the course of the experiment (pure drinking water as control) 77 . At endpoint (8 or 14 weeks after AOM injection, for bacterial gavage or formate treatment respectively), mice were euthanized via intraperitoneal injection of medetomidine (1 mg kg −1 ) and ketamine (150 mg kg −1 ).…”