Effects of fermented soymilk with Lacticaseibacillus paracasei YIT 9029 on gut microbiota and defecation habits: a randomised, double-blind, placebo-controlled study.

Previous studies have demonstrated that soymilk and Lacticaseibacillus paracasei YIT 9029 (strain Shirota: LcS) each beneficially affect the gut microbiota and defecation habits. To investigate the effects of daily consumption of fermented soymilk containing LcS (FSM), we conducted a randomised, double-blind, placebo-controlled study of 112 healthy Japanese adults with a low faecal Bifidobacterium count. They consumed 100 ml FSM or placebo (unfermented soymilk base) once daily for 4 weeks. Their gut microbiota was analysed by 16S rRNA gene amplicon sequencing and quantitative reverse transcription-polymerase chain reaction (PCR), and faecal short-chain fatty acids (SCFAs) and urinary putrefactive products were assessed during the pre- and post-consumption periods. Defecation habits were examined weekly using a subjective questionnaire. In the post-consumption period, living LcS were not detected in two subjects in the FSM group (n = 57) but were detected in one subject in the SM group (n = 55). The FSM group had a significantly higher number and relative abundance of faecal lactobacilli compared with the placebo group. The relative abundance of Bifidobacterium, alpha-diversity of microbiota, and concentrations of acetate and total SCFAs in faeces were significantly increased in the FSM group, although no significant differences were detected between the groups. The number of defecations and defecation days per week significantly increased in both groups. Subgroup analysis of 109 subjects, excluding 3 with inconsistent LcS detection (2 and 1 subjects in the FSM and SM groups, respectively), revealed that the FSM group (n = 55) had significantly greater increases in faecal acetate concentration compared with the SM group (n = 54) and significant upregulation of pathways related to energy production or glucose metabolism in the gut microbiota. These findings suggest that daily FSM consumption improves the gut microbiota and intestinal environment in healthy adults and may help to maintain health and prevent diseases. Registered at the University Hospital Medical Information Network (UMIN) clinical trials registry under: UMIN 000035612.

Effects of fermented soymilk with Lactobacillus casei Shirota on skin condition and the gut microbiota: a randomised clinical pilot trial.

Several clinical studies have shown that isoflavones and Lactobacillus casei Shirota (LcS) have beneficial effects on skin condition and the gut microbiota, respectively. Thus, we investigated the effects of consecutive intake of fermented soymilk (FSM) with LcS on skin condition and the gut microbiota, as well as isoflavone bioavailability, in a randomised, double-blind, placebo-controlled trial as a pilot study. Sixty healthy premenopausal Japanese women received FSM containing a moderate level of isoflavone aglycones and a probiotic LcS, or soymilk (SM) containing neither of them, twice a day for 8 weeks. Skin condition was assessed by a subjective questionnaire for face and morphological analysis of the stratum corneum on the inner forearm. Faecal microbiota and urinary isoflavone were analysed by 16S rRNA gene amplicon sequencing and high-performance liquid chromatography tandem mass spectrometry, respectively. Both the FSM and SM groups had improved skin condition as assessed from scores of overall satisfaction, dryness, moisture, elasticity, coarseness, pigmentation and/or stratum corneum morphology, as well as significantly increased levels of urinary isoflavones during the intake period compared with the pre-intake period, although there were no significant differences between the two groups. There was a significant positive correlation between urinary isoflavone levels and skin questionnaire scores. In contrast, the relative abundance levels of Lactobacillaceae significantly increased and those of Bifidobacteriaceae tended to increase during the intake period compared with the pre-intake period. For the after-intake period they only decreased significantly in the FSM group. The levels of Enterobacteriaceae and Porphyromonadaceae significantly decreased during the intake period in the FSM group. These findings suggest that daily intake of FSM, as well as SM, provides health benefits that improve skin condition via increased levels of isoflavone absorption in the body, and that only FSM beneficially modifies the gut microbiota in premenopausal healthy women.

Cytoplasmic domain is not essential for the cell adhesion activities of gicerin, an Ig-superfamily molecule.

Gicerin is a cell adhesion molecule in the immunoglobulin (Ig) superfamily and is expressed abundantly during development in the nervous system. It has homophilic cell adhesion activity and also has heterophilic binding activity with NOF (neurite outgrowth factor) and mediates neurite extension. There are two isoforms of gicerin, one with a short (s-gicerin) and the other with a longer cytoplasmic domain (l-gicerin). We have reported that s-gicerin possesses stronger activities than l-gicerin during cell aggregation, in NOF-binding, and in neurite extension. In this study, we established cell lines which expressed a mutant-gicerin whose cytoplasmic domain was deleted and we compared the above three biological activities of the mutant-gicerin with those of s- and l-gicerin. We found that the mutant-gicerin retained all these activities, but the activities were weaker than those of s-gicerin and almost the same as those of l-gicerin. We concluded that the cytoplasmic domain of gicerin is not essential for optimal adhesive activities of gicerin, but might be involved in the regulation of its activities.

Neurite promotion from ciliary ganglion neurons by gicerin.

Gicerin is a cell adhesion molecule of an immunoglobulin superfamily member and transiently expressed on the surface of neurons such as retinal ganglion cells during synaptogenesis. Gicerin is a receptor for NOF (neurite outgrowth factor) that belongs to the laminin family, and mediates neurite extension induced by NOF. As we have reported, gicerin also exhibits homophilic cell adhesion activity, we compared the patterns of extending neurites induced by homophilic and heterophilic cell adhesion activities of gicerin using ciliary ganglion (CG) neurons. CG neurons expressed gicerin and extended neurites on a feeder layer of gicerin-transfected cells, suggesting a neurite extension by gicerin-gicerin (homophilic) interaction. We found that CG neurons cultured on gicerin-transfected cells extended slightly branched neurites, while those cultured on NOF-coated substratum extended many long branched neurites. It is suggested that neurites induced by homophilic or heterophilic cell adhesion activities of gicerin differ in the length and branching.

Expression and functional analysis of a novel isoform of gicerin, an immunoglobulin superfamily cell adhesion molecule.

We have cloned a novel cDNA of gicerin, a cell adhesion molecule belonging to the immunoglobulin superfamily. Both gicerin isoforms share the same extracellular domain, which has five immunoglobulin-like loop structures and a transmembrane domain as s-gicerin, but differ in the cytoplasmic tail domain. As the newly identified form has a larger cytoplasmic domain than the previously reported form, we refer to them as l-gicerin and s-gicerin, respectively. l-gicerin is transcribed from a distinct mRNA containing an inserted sequence not found in s-gicerin mRNA which caused a frameshift for the coding region for a cytoplasmic domain. Previous studies demonstrated that gicerin showed a doublet band of 82 and 90 kDa in chicken gizzard smooth muscle. We report that the 82-kDa protein corresponds to s-gicerin and the 90-kDa protein to l-gicerin. We also found that the two gicerin isoforms are expressed differentially in the developing nervous system. Functional analysis of these gicerin isoforms in stable transfectants revealed that they had differ in their homophilic adhesion properties, as well as in heterophilic cell adhesion assayed with neurite outgrowth factor. In addition, these isoforms have neurite-promoting activity by their homophilic adhesion, but differ in their ability to promote neurite outgrowth.

Expression of gicerin in development, oncogenesis and regeneration of the chick kidney.

Neurite outgrowth factor, which promotes neurite extension from neuronal cells, is an extracellular matrix glycoprotein belonging to the laminin family. Gicerin is a protein that binds neurite outgrowth factor. Its cDNA cloning has revealed that it is a novel cell adhesion molecule belonging to the immunoglobulin super-family. Functional analysis demonstrates that gicerin possesses homophilic binding activity as well as heterophilic binding activity with neurite outgrowth factor. We examined the role and expression of neurite outgrowth factor and gicerin in chick kidney during development. In the embryonic kidney, gicerin was found to be highly expressed both on ureteric bud cells and metanephrogenic mesenchymal cells, when the mesenchymal cells become condensed to be converted into polarized epithelial cells. In the adult kidney, the expression of gicerin was decreased and restricted to the glomerulus, proximal tubule and medullary loop. On the other hand, neurite outgrowth factor was constitutively expressed in the basement membranes of tubules and the matrices of glomeruli during development. As some molecules which are expressed during embryogenesis and suppressed after maturation are re-expressed in tumor cells or tissues during regeneration, we also examined the expression of gicerin in chicken Wilms' tumor and regenerating kidney in interstitial nephritis. Gicerin was remarkably upregulated in Wilms' tumor and re-expressed in collecting ducts recovering from interstitial nephritis. These findings suggest that gicerin could play a role not only in normal renal development but also in oncogenesis and regeneration.