Rat Intestinal Acetic Acid and Butyric acid and Effects of Age, Sex, and High-fat Diet on the Intestinal Levels in Rats

Tributyrin reverses the deleterious effect of saturated fat on working memory and synaptic plasticity in juvenile mice: differential effects in males and females

Short-chain fatty acids, such as butyric acid, derived from the intestinal fermentation of dietary fiber, have been proposed as a treatment for certain pathologies of the central nervous system. Our research group has shown that tributyrin (TB), a butyric acid prodrug, reverses deficits in spatial memory and modulates hippocampal synaptic plasticity. In the present work, diets enriched in either saturated (SOLF; Saturated OiL-enriched Food) or unsaturated (UOLF; Unsaturated OiL-enriched Food) fat were supplied during either 2 h or 8 weeks to 5-week-old male and female mice undergoing a treatment schedule with TB. After the dietary treatment, spatial learning and memory (SLM) was assessed in both the Y-maze and the eight-arm radial maze (RAM). Hippocampal expression of genes involved in glutamatergic transmission as well as synaptic plasticity (long-term potentiation -LTP- and long-term depression -LTD-) were also analyzed. Our results show that 2 h of SOLF intake impaired LTP as well as the performance in the Y-Maze in juvenile male mice whereas no effect was found in females. Moreover, TB reversed both effects in SLM and LTP in males. In the case of chronic intake, both SOLF and UOLF deteriorated SLM measured in the RAM in both sexes whereas TB only reversed LTP impairment induced by SOLF in male mice. These results suggest that TB may have a potentially beneficial influence on learning and memory processes, contingent upon the type of diet and the sex of the individuals.

Maternal high-fat diet alters the neurobehavioral, biochemical and inflammatory parameters of their adult female rat offspring

BACKGROUND

Lipid metabolism dysregulations have been associated with depressive and anxious behaviors which can affect pregnant and lactating individuals, with indications that such changes extend to the offspring. Therefore, the aim of this study was to evaluate the effect of a maternal high-fat diet on the neurobehavioral, biochemical and inflammatory parameters of their adult female offspring.

METHODS

Wistar rats ± 90 days old were mated. The dams were allocated to consume a control (CTL) or high-fat (HFD) diet during pregnancy and lactation. After weaning, the female offspring from the CTL (N=10) and HFD (N=10) groups received standard chow. The offspring behavioral tests were started at 120 days old. Then, the somatic measures were evaluated followed by euthanasia, histological and biochemical analyses.

RESULTS

The HFD group had less ambulation and longer immobility time in the open field test compared to the CTL. The HFD group had lower HDL (48.4%) and a higher adiposity (71.8%) and LDL (62.2%) than the CTL. The CTL had a higher organic acid concentration in the intestine, mainly acetic and butyric acids, however the HFD had a higher citric and acetic acid concentration in the brain and ischemic lesion in the hippocampus with a higher NF-κB concentration.

CONCLUSION

The results demonstrate deleterious effects of a maternal HFD on the neurobehavioral and biochemical parameters of their offspring which may be associated with the role of organic acids and NF-κB in fetal programming.

Effect of Clostridium butyricum on High-Fat Diet-Induced Intestinal Inflammation and Production of Short-Chain Fatty Acids

BACKGROUND/AIMS

A high-fat diet (HFD) can cause intestinal inflammation and alter the gut microbiota; probiotics, however, are known to have anti-inflammatory effects. This study aimed to investigate the response of rat colon to HFD and the effect of Clostridium butyricum on HFD-induced intestinal inflammation and production of short-chain fatty acids (SCFAs) according to sex.

METHODS

Male and female 6-week-old Fischer-344 rats were fed a chow diet or HFD for 8 weeks, and Biovita or three different concentrations of C. butyricum were orally gavaged. The levels of tight junction proteins (TJPs), inflammatory markers in the ascending colonic mucosa, and bile acids (BAs) and SCFAs in stool were measured.

RESULTS

HFD significantly increased the histological inflammation scores and fat proportions. Fecal BA levels were higher in the HFD group than in the control group, with a more prominent increase in deoxycholic acid/cholic acid after probiotics administration in females; however, no statistically significant differences were observed. TJPs showed an opposite response to HFD depending on sex, and tended to increase and decrease after HFD in males and females, respectively. The HFD-reduced TJPs were recovered by probiotics, with some statistical significance in females. HFD-decreased butyric acid in stools appeared to be recovered by probiotics in males, but not in females. The expression of inflammatory markers (TNF-α) was increased by HFD in males and decreased with medium-concentration probiotic supplementation. The opposite was observed in females. MPO was increased by HFD in both sexes and decreased by probiotic supplementation.

CONCLUSIONS

The probiotic C. butyricum improved indicators of HFD-induced colonic inflammation such as levels of inflammatory markers and increased the production of SCFAs and the expression of TJPs. These effects tended to be more pronounced in male rats, showing sex difference.

Fecal Microbial Enterotypes Differentially Respond to a High-fat Diet Based on Sex in Fischer-344 Rats

The gut microbiota interacts with the host gut environment, which is influenced by such factors as sex, age, and host diet. These factors induce changes in the microbial composition. The aim of this study was to identify differences in the gut microbiome of Fisher-344 (F344) rats fed a high-fat diet (HFD), depending on their age and sex. Fecal microbiomes from 6-, 31-, and 74-week-old, and 2-year-old both male and female rats (corresponding to 5-, 30-, 60-, and 80-year-old humans) were analyzed using 16S rRNA gene sequencing, phylogenetic investigation of communities by reconstruction of unobserved states, and enterotype (E) assessment. Moreover, the effect of an HFD on colonic epithelial cells was measured using real-time quantitative PCR. Alpha diversity decreased in the HFD group regardless of age and sex. Based on the enterotype clustering of the whole fecal microbiome, clusters from male rats were divided into E1 and E2 enterotypes, while clusters from female rats were divided into E1, E2, and E3 enterotypes. The female E3 group showed a significantly high abundance in the Ruminococcus genus and expression of Tlr2 mRNA, which may reflect compensation to the HFD. Moreover, the female E3 group showed a lower ratio of opportunistic pathogenic strains to commensal strains compared to the female E2 group. Administration of an HFD influenced the rat fecal microbiota in all assessed age groups, which could be further differentiated by sex. In particular, female rats showed a compensatory enterotype response to an HFD compared to male rats.

The role of Bacillus acidophilus in osteoporosis and its roles in proliferation and differentiation

Background

Osteoporosis is one of the most closely related diseases associated with the elderly. In recent years, the studies found that gut microbiota can cause osteoporosis. We evaluated the role of Bacillus acidophilus in osteoporosis and its roles in proliferation and differentiation.

Methods

We selected 5 healthy people and 10 osteoporosis patients and analyzed their level of 25‐hydroxyvitamin D and procollagen type I N‐terminal peptide (PINP), the characteristic of gut microbiota. The effect of lactobacillus acidophilus and Lactobacillus rhamnosus supernatant and butanoic acids on proliferation, differentiation, and maturity of osteoblasts MC3T3‐E1 and osteoclasts RAW 264.7 cells and the activity of alkaline phosphatase, concentration of osteocalcin, and the expression of RUNX2, RANK, NFATc1, cathepsin K, DC‐STAMP, OSCAR, WNT2, and CTNNB1 were measured in the above cell lines.

Results

The diversity of gut microbiota in osteoporosis patients is decreased and imbalanced with lower abundance of lactobacillus and butyric acid bacteria; meanwhile, 25‐hydroxyvitamin D and PINP of osteoporosis patient were significantly lower than the normal group. The proliferation, differentiation, and maturity of MC3T3‐E1 cells were stimulated; the activity of alkaline phosphatase, concentration of osteocalcin, and the expression of RUNX2, NFATc1, cathepsin K, DC‐STAMP, OSCAR, WNT2, and CTNNB1 were improved by supernatant of lactobacillus acidophilus, Lactobacillus rhamnosus and butanoic acids; however, the proliferation, differentiation, maturity, and the expression of RANK, NFATc1, cathepsin K, DC‐STAMP, OSCAR, WNT2, and CTNNB1 in RAW 264.7 cells were suppressed.

Conclusions

The lactobacillus acidophilus and Lactobacillus rhamnosus supernatant could stimulate the proliferation, differentiation, and maturation of osteoblasts; the production of butyric acid may be the potential mechanism.

Metabolic and functional interplay between gut microbiota and fat-soluble vitamins

Gut microbiota is a complex ecosystem seen as an extension of human genome. It represents a major metabolic interface of interaction with food components and xenobiotics in the gastrointestinal (GI) environment. In this context, the advent of modern bacterial genome sequencing technology has enabled the identification of dietary nutrients as key determinants of gut microbial ecosystem able to modulate the host-microbiome symbiotic relationship and its effects on human health. This article provides a literature review on functional and molecular interactions between a specific group of lipids and essential nutrients, e.g., fat-soluble vitamins (FSVs), and the gut microbiota. A two-way relationship appears to emerge from the available literature with important effects on human metabolism, nutrition, GI physiology and immune function. First, FSV directly or indirectly modify the microbial composition involving for example immune system-mediated and/or metabolic mechanisms of bacterial growth or inhibition. Second, the gut microbiota influences at different levels the synthesis, metabolism and transport of FSV including their bioactive metabolites that are either introduced with the diet or released in the gut via entero-hepatic circulation. A better understanding of these interactions, and of their impact on intestinal and metabolic homeostasis, will be pivotal to design new and more efficient strategies of disease prevention and therapy, and personalized nutrition.