Association between a low-carbohydrate diet and macronutrient intake with the gut microbiome, and their interaction with dyslipidemia among Korean adults.

Background: The prevalence of dyslipidemia has increased in recent years; however, it remains a modifiable condition through diet and gut microbiome modulation. Yet, evidence from population-based studies remains limited. This study aimed to investigate the relationships among a low-carbohydrate diet (LCD), macronutrient intake, and the gut microbiome, and to evaluate their interaction effects on dyslipidemia in a Korean population.

Deciphering gut microbiome patterns from host preferences and microbial interactions in healthy Korean individuals.

Background: The gut microbiome is crucial for human health maintenance and disease development, yet limited understanding of its structure and maintenance hinders effective microbiome-based health improvement strategies. We investigated gut microbiome compositional patterns in healthy Koreans (n = 890), identifying six clusters (I-VI) with unique compositions and host preferences.

Results: Each cluster had a distinct topological structure within the microbial interaction network, underscoring its diverse roles in maintaining microbial communities.

Balancing harm and harmony: Evolutionary dynamics between gut microbiota-derived flagellin and TLR5-mediated host immunity and metabolism.

The gut microbiota maintains host health and shapes immune responses through intricate host-microbe interactions. Bacterial flagellin, a key microbe-associated molecular pattern, is recognized by Toll-like receptor 5 (TLR5) and NOD-like receptor family caspase activation and recruitment domain-containing 4 inflammasome. This dual recognition maintains the delicate balance between immune tolerance and activation, thereby influencing health and disease outcomes.

Effects of Limosilactobacillus fermentum KBL375 on Immune Enhancement and Gut Microbiota Composition in Cyclophosphamide-Induced Immunosuppressed Mice.

This study evaluated the immune-enhancing efficacy of Limosilactobacillus fermentum KBL375 isolated from the feces of healthy Koreans. KBL375-treated splenocytes showed enhancement of cytotoxicity against YAC-1 cells, the target of natural killer (NK) cells, with an increase in CD335, granzyme B, perforin, and interferon-gamma (IFN-γ). Oral administration of KBL375 in mice with cyclophosphamide (CP)-induced immunosuppression improved body weight and immune functions, including immune organ indices, lymphocyte proliferations, and immunoglobulin (Ig) A levels.

Understanding the role of the gut microbiome in solid tumor responses to immune checkpoint inhibitors for personalized therapeutic strategies: a review.

Immunotherapy, especially immune checkpoint inhibitor (ICI) therapy, has yielded remarkable outcomes for some patients with solid cancers, but others do not respond to these treatments. Recent research has identified the gut microbiota as a key modulator of immune responses, suggesting that its composition is closely linked to responses to ICI therapy in cancer treatment. As a result, the gut microbiome is gaining attention as a potential biomarker for predicting individual responses to ICI therapy and as a target for enhancing treatment efficacy.

Fecal Microbial Dysbiosis Is Associated with Colorectal Cancer Risk in a Korean Population.

Purpose: The association between the fecal microbiota and colorectal cancer (CRC) risk has been suggested in epidemiologic studies. However, data from large-scale population-based studies are lacking.

Materials And Methods: In this case-control study, we recruited 283 CRC patients from the Center for Colorectal Cancer, National Cancer Center Hospital, Korea to perform 16S rRNA gene sequencing of fecal samples.

Lacticaseibacillus paracasei completely utilizes fructooligosacchrides in the human gut through β-fructosidase (FosE).

The fecal microbiota of two healthy adults was cultivated in a medium containing commercial fructooligosaccharides [FOS; 1-kestose (GF), nystose (GF), and 1-fructofuranosylnystose (GF)]. Initially, the proportions of lactobacilli in the two feces samples were only 0.42% and 0.

Gut microbiome in healthy aging versus those associated with frailty.

As the proportion of older people in the world's population steadily increases, there is an urgent need to identify ways to support healthy aging. The gut microbiome has been proposed to be involved in aging-related diseases and has become an attractive target for improving health in older people. Herein, we cover the relationship between the gut microbiome and chronological age in adults, and then, we discuss the gut microbiome features associated with frailty, as a hallmark of unhealthy aging in older people.

A qRT-PCR Method Capable of Quantifying Specific Microorganisms Compared to NGS-Based Metagenome Profiling Data.

Metagenome profiling research using next-generation sequencing (NGS), a technique widely used to analyze the diversity and composition of microorganisms living in the human body, especially the gastrointestinal tract, has been actively conducted, and there is a growing interest in the quantitative and diagnostic technology for specific microorganisms. According to recent trends, quantitative real-time PCR (qRT-PCR) is still a considerable technique in detecting and quantifying bacteria associated with the human oral and nasal cavities, due to the analytical cost and time burden of NGS technology. Here, based on NGS metagenome profiling data produced by utilizing 100 gut microbiota samples, we conducted a comparative analysis for the identification and quantification of five bacterial genera (, , , , and ) within same metagenomic DNA samples through qRT-PCR assay in parallel.

Effect of Supplementation on the Gut Microbial Composition of Healthy Korean Adults: A Single-Group Pilot Study.

is a type of meal-replacement product or dietary supplement comprising an uncooked and dried plant-based food mixture with various health-promoting properties, such as antidiabetic, anti-dyslipidemic, antioxidant, and anticancer properties. Although these properties are considered attributable to the various bioactive components absorbed through the intestine and its remolding effect on intestinal microorganisms, the effect of supplementation on gut microbiota profiles has not yet been studied. In this study, we investigated the effect of administration on the composition of gut microbiota.

Accuracy comparison study of new smartphone-based semen analyzer versus laboratory sperm quality analyzer.

Purpose: This study aimed to test the clinical efficacy of a portable smartphone-based App assisted semen analysis (SA) system, O'VIEW-M PRO® to clinically accurate in comparison with results of laboratory-based conventional semen analyses including manual microscopic and computer-assisted semen analysis (CASA) for self-evaluation of seminal parameters.

Materials And Methods: From January to May 2021, a total of 39 semen samples were analyzed for the sperm concentration and motility with new smartphone-based App assisted semen analyzer, O'VIEW-M PRO®, and results compared with those from laboratory-based manual microscopic SA with Makler Counting Chamber and CASA.

Results: The coefficient factors among the results of the measurement with Makler chamber and laboratory-based CASA comparing to O'VIEW-M PRO® were 0.

Gut Microbiome Structure and Association with Host Factors in a Korean Population.

Characterizing the gut microbiome in the healthy population is the first step in elucidating its associations with host health conditions. Populations with different diet patterns, lifestyles, and genetic backgrounds harbor different gut microbes. In this study, we characterized the gut microbiome of 890 healthy Koreans using 16S rRNA sequencing.

The effect of taxonomic classification by full-length 16S rRNA sequencing with a synthetic long-read technology.

Characterizing the microbial communities inhabiting specimens is one of the primary objectives of microbiome studies. A short-read sequencing platform for reading partial regions of the 16S rRNA gene is most commonly used by reducing the cost burden of next-generation sequencing (NGS), but misclassification at the species level due to its length being too short to consider sequence similarity remains a challenge. Loop Genomics recently proposed a new 16S full-length-based synthetic long-read sequencing technology (sFL16S).

Association Between Gut Microbiome and Frailty in the Older Adult Population in Korea.

Frailty is a common geriatric syndrome associated with the risk of adverse health outcomes. Recently, 2 key pathophysiological characteristics of frailty, altered energy metabolism and dysregulated immunity, have been reported to be associated with gut microbiome dysbiosis, indicating that the gut microbiome plays a role in frailty. However, few studies have directly examined the relationship between the gut microbiome and frailty.

Evaluation of fecal DNA extraction protocols for human gut microbiome studies.

Background: DNA extraction is an important factor influencing the microbiome profile in fecal samples. Considering that the QIAamp DNA Stool Mini Kit, one of the most commonly used DNA extraction kits, is no longer manufactured, this study aimed to investigate whether a new commercially available kit, the QIAamp PowerFecal Pro DNA Kit, yields comparable microbiome profiles with those previously obtained using the QIAamp DNA Stool Mini Kit.

Results: We extracted DNA from fecal samples of 10 individuals using three protocols (protocol P of the QIAamp PowerFecal Pro DNA Kit, and protocols SB and S of the QIAamp DNA Stool Mini Kit with and without an additional bead-beating step, respectively) in triplicate.

Roseburia spp. Abundance Associates with Alcohol Consumption in Humans and Its Administration Ameliorates Alcoholic Fatty Liver in Mice.

Although a link between the gut microbiota and alcohol-related liver diseases (ALDs) has previously been suggested, the causative effects of specific taxa and their functions have not been fully investigated to date. Here, we analyze the gut microbiota of 410 fecal samples from 212 Korean twins by using the Alcohol Use Disorders Identification Test (AUDIT) scales to adjust for host genetics. This analysis revealed a strong association between low AUDIT scores and the abundance of the butyrate-producing genus Roseburia.

Age-related compositional and functional changes in micro-pig gut microbiome.

Age-related changes in human gut microbiota composition have been reported, and such changes might be influenced by the intake of nutrients or diets. To investigate the effects of aging on the gut microbiota independent of nutrient effects, we analyzed the gut microbiomes of 126 micro-pigs at a wide range of ages from newborns to 10 years old. The micro-pigs were reared in a constantly controlled environment.

Validation of a smartphone-based, computer-assisted sperm analysis system compared with laboratory-based manual microscopic semen analysis and computer-assisted semen analysis.

Purpose: This study aimed to evaluate the clinical efficacy of a portable smartphone-based system for computer-assisted semen analysis (CASA) compared with the results of manual microscopic semen analysis (SA) and laboratory-based CASA for self-evaluation of semen parameters by a male partner.

Materials And Methods: From July 2017 to February 2018, a total of 28 samples were analyzed for concentration and motility with a smartphone-based CASA system and the results compared with those from laboratory-based CASA and manual microscopic SA with a Makler Counting Chamber (SEFI Medical Instruments, Israel).

Results: Sperm concentration and motility measured with the smartphone-based CASA system were positively correlated with the microscopic-based results.

Effect of raw potato starch on the gut microbiome and metabolome in mice.

The gut microbiome plays a pivotal role in human health and is affected by various factors. To investigate the association between phenotypic and microbiota-related changes in the gut and a raw starch-based diet, we fed mice with different starch substitutes (corn, wheat, rice, and potato) for 16 weeks. The potato starch-fed group showed the lowest weight gain and fat tissue accumulation of all the groups, as well as the highest insulin sensitivity.