CXCL5/CXCL8 induces neutrophilic inflammation in peri-implantitis.

OBJECTIVE AND BACKGROUND: This research aimed to examine the role of C-X-C motif chemokine ligand 5 (CXCL5) and C-X-C motif chemokine ligand 8 (CXCL8; also known as IL-8) in neutrophilic inflammation triggered by peri-implantitis and to shed light on the underlying mechanisms that link them to the development of this condition. MATERIALS: This study included 40 patients who visited the Department of Periodontology at Kyungpook University Dental Hospital. They were divided into two groups based on their condition: healthy implant (HI) group (n = 20) and peri-implantitis (PI) group (n = 20). Biopsy samples of PI tissue were collected from the patients under local anesthesia. HI tissue was obtained using the same method during the second implant surgery. To construct libraries for control and test RNAs, the QuantSeq 3' mRNA-Seq Library Prep Kit (Lexogen, Inc., Austria) was used according to the manufacturer's instructions. Samples were pooled based on representative cytokines obtained from RNA sequencing results and subjected to Reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Hematoxylin and eosin staining, and immunohistochemistry (IHC) analysis were performed to visually assess expression levels and analyze tissue histology. Student's t-test was employed to conduct statistical analyses. RESULTS: Initially, heatmaps were used to examine gene expression variations between the HI and PI groups based on the results of RNA sequencing. Notably, among various cytokines, CXCL5 and CXCL8 had the highest expression levels in the PI group compared with the HI group, and they are known to be associated with inflammatory responses. In the gingival tissues, the expression of genes encoding cytokines such as interleukin (IL)-1ß, tumor necrosis factor-alpha (TNF)-α, interleukin (IL)-6, and CXCL5/CXCL8 was assessed via RT-qPCR. The mRNA expression level of CXCL5/CXCL8 significantly increased in the PI group compared with the HI group (p < .045). Contrarily, the mRNA expression level of interleukin 36 receptor antagonist (IL36RN) significantly decreased (p < .008). IHC enabled examination of the distribution and intensity of CXCL5/CXCL8 protein expression within the tissue samples. Specifically, increased levels of CXCL5/CXCL8 promote inflammatory responses, cellular proliferation, migration, and invasion within the peri-implant tissues. These effects are mediated through the activation of the PI3K/Akt/NF-κB signaling pathway. CONCLUSIONS: This study found that the PI sites had higher gene expression level of CXCL8/CXCL5 in the soft tissue than HI sites, which could help achieve more accurate diagnosis and treatment planning.

The impact of raw material form and starter culture inoculation on bacterial communities and metabolites in fermented anchovy sauce.

This study explored the dynamics of anchovy sauce fermentation and investigated how the raw material form and the use of starter cultures affect bacterial and metabolite profiles. Using a comprehensive approach, we examined the fermentation process using anchovies in two forms (whole and ground) and three different starter cultures. The use of ground anchovies resulted in an accelerated fermentation process for anchovy sauce; however, the increased diversity of bacterial phylotypes and altered accumulation of biogenic amines were observed. Inoculation of starter cultures resulted in a shift from spontaneous to controlled fermentation, highlighting their ability to regulate bacterial communities. Despite a slightly reduced fermentation rate, inoculation with Tetragenococcus halophilus was shown to be a potent method for reducing biogenic amines and affecting metabolite profiles. As the industry strives to balance fermentation speed and quality, our research could provide insights for improving the efficiency, safety, and quality of anchovy sauce production.

Selective influence of garlic as a key ingredient in kimchi on lactic acid bacteria in a fermentation model system.

Garlic is an essential ingredient added to kimchi, a fermented vegetable, in small amounts owing to its sensory and antibacterial properties. This study aimed to elucidate the complex relationship between garlic and specific lactic acid bacteria (LAB) and the resulting metabolite changes in a controlled kimchi model system using nine strains as mixed and individual starters. The group without garlic using mixed starters showed the highest LAB growth activity, which influenced lactic acid production, pH, and titratable acidity. The group without garlic also showed differences in the composition of bacteria, such as Latilactobacillus sakei, Levilactobacillus brevis, unclassified Leuconostoc, and Weissella koreensis, during the fermentation period. In addition, the altering patterns of metabolites in the group without garlic during fermentation differed from those in the group with garlic. In addition, the metabolic profile of L. brevis group was mostly different from that of the other strains in the controlled model kimchi system using individual starters, suggesting that changes in LAB composition by garlic could subsequently affect metabolites during fermentation. This study provides valuable insights into the complex interactions among food ingredients, LAB succession, and metabolite production during fermentation.

Impact of essential and optional ingredients on microbial and metabolic profiles of kimchi.

This study aimed to examine the impacts of essential and optional ingredients on the microbial and metabolic profiles of kimchi during 100 days of fermentation, using a mix-omics approach. Kimchi manufactured without essential ingredients (e.g., red pepper, garlic, ginger, green onion, and radish) had lower lactic acid content. The absence of garlic was associated with a higher proportion of Latilactobacillus and Lactococcus, while the absence of red pepper was associated with a greater proportion of Leuconostoc than the control group. In addition, red pepper and garlic served as primary determinants of the levels of organic acids and biogenic amines. Sugar was positively correlated with the levels of melibiose, and anchovy sauce was positively correlated with the levels of amino acids such as methionine, leucine, and glycine. These findings contribute to a fundamental understanding of how ingredients influence kimchi fermentation, offering valuable insights for optimizing kimchi production to meet various preferences.

Effects of seasonal harvest of kimchi cabbage on microbial and metabolic profiles of kimchi.

Kimchi cabbage, the key ingredient in kimchi, is cultivated year-round to meet high production demands. This study aimed to examine the effects of seasonal harvesting (spring, summer, fall, and winter) on the microbial and metabolic profiles of kimchi during 30 days of fermentation. Lactic acid bacteria distribution is notably influenced by seasonal variations, with Latilactobacillus dominant in fall-harvested kimchi group and Weissella prevailing in spring, summer, and winter. The microbial communities of spring and fall group exhibited similar profiles before fermentation, whereas the microbial communities and metabolic profiles of spring and summer group were similar after 30 days of fermentation. Seasonal disparities in metabolite concentrations, including glutamic acid, serine, and cytosine, persist throughout fermentation. This study provides a comprehensive understanding of the substantial impact of seasonal harvesting of kimchi cabbage on the microbial and metabolic characteristics of kimchi, providing valuable insights into producing kimchi with diverse qualities.

Effects of ingredient size on microbial communities and metabolites of radish kimchi.

In this study, changes in physicochemical characteristics, microbial communities, and metabolites were investigated to identify the fermentation characteristics of radish kimchi according to the size of radish cubes used. The small-sized radish kimchi group showed the highest hardness value and glucose content in the early stages of fermentation. The relative abundance of major lactic acid bacteria, including Leuconostoc, Weissella, and Lactobacillus, was the highest in the small-sized radish kimchi group on day 5 of fermentation, which resulted in rapid production of lactic acid, thereby causing a decrease in pH and an increase in titratable acidity. The size of the radish in kimchi plays a pivotal role in determining various factors, most notably during the first 5 days of fermentation, leading to marked metabolic changes. A total of 17 metabolites, including glucose, sucrose, lactic acid, malic acid, citric acid, and GABA, exhibited significant differences in the small-size radish kimchi group. Interestingly, the sucrose content was higher in the large-sized radish group at the beginning of fermentation. This study revealed that ingredient size can selectively affect the growth of specific microorganisms in an environment where several microorganisms coexist, which could change the quality of radish kimchi.