Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease and the leading cause of liver-related deaths worldwide. It has been established that microorganisms are involved in the interaction between the intestinal lumen and the liver; therefore, studies on probiotics as potential candidates are increasing. This study evaluated the effects of Limosilactobacillus fermentum MG4294 and Lactiplantibacillus plantarum MG5289 on NAFLD. The MG4294 and MG5289 reduced lipid accumulation in FFA-induced HepG2 by suppressing the adipogenic proteins through the regulation of AMP-activated protein kinase (AMPK). The administration of these strains in the HFD-induced mice model lowered body weight, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and cholesterol levels. In particular, MG4294 and MG5289 restored liver TG and TC to normal levels by lowering lipid and cholesterol-related proteins via the modulation of AMPK in the liver tissue. In addition, the administration of MG4294 and MG5289 reduced pro-inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-1β-, and IL6) in the intestinal tissues of the HFD-induced mouse model. In conclusion, MG4294 and MG5289 can be presented as probiotics with the potential to prevent NAFLD.

Skin photoaging, which causes wrinkles, increased epidermal thickness, and rough skin texture, is induced by ultraviolet B (UVB) exposure. These symptoms by skin photoaging have been reported to be involved in the reduction of collagen by the expression of matrix metalloproteinases (MMPs) and activator protein-1 (AP-1). This study investigated the protective effects of Bifidobacterium animalis subsp. lactis MG741 (Bi. lactis MG741) in Hs-68 fibroblasts and hairless mice (HR-1) following UVB exposure. We demonstrated that the Bi. lactis MG741 reduces wrinkles and skin thickness by downregulating MMP-1 and MMP-3, phosphorylation of extracellular signal-regulated kinase (ERK), and c-FOS in fibroblasts and HR-1. Additionally, in UVB-irradiated dorsal skin of HR-1, Bi. lactis MG741 inhibits the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), an inflammation-related factor. Thus, Bi. lactis MG741 has the potential to prevent wrinkles and skin inflammation by modulating skin photoaging markers.

Ultraviolet B (UVB) exposure causes a breakdown of collagen, oxidative stress, and inflammation. UVB activates mitogen-activated protein kinase (MAPK), activator protein-1 (AP-1), and matrix metalloproteinases (MMPs). In this study, we evaluated 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⁺) radical scavenging activity and the photoprotective effect of lactic acid bacteria LAB strains, including Lactobacillus, Bifidobacterium, and Streptococcus genera in UVB-exposed skin fibroblasts. Nine LAB strains displayed antioxidant activity by regulating superoxide dismutase in UVB-exposed skin fibroblasts. Four LAB strains (MG4684, MG5368, MG4511, and MG5140) recovered type I procollagen level by inhibiting MMPs, MAPK, and AP-1 protein expression. Additionally, these four strains reduced the expression of proinflammatory cytokines by inhibiting oxidative stress. Therefore, L. fermentum MG4684, MG5368, L. rhamnosus MG4511, and S. thermophilus MG5140 are potentially photoprotective.

Lee JY, et al. J Nutr Health. 2019 Jun;52(3):250-257. https://doi.org/10.4163/jnh.2019.52.3.250

Periodontitis is a chronic inflammatory disease characterized by tooth loss due to inflammation and the loss of alveolar bone. Periodontitis is closely related to various systemic diseases and is emerging as a global health problem. In this study, we investigated the anti-inflammatory effect of lactic acid bacteria (LAB) in vitro on Porphyromonas gingivalis (P. gingivalis) LPS-activated RAW264.7 and human gingival fibroblasts-1 (HGF-1) cells and the anti-osteoclastogenic effect of LAB on RANKL-induced RAW264.7 cells. All LAB strains (Lacticaseibacillus rhamnosus MG4706, MG4709, and MG4711) inhibited nitric oxide (NO)/inducible nitric oxide synthase (iNOS) in P. gingivalis LPS-activated RAW264.7 cells and pro-inflammatory cytokines (IL-1β and IL-6) and matrix metalloproteinase (MMP-8 and MMP-9) in HGF-1 cells. In addition, LAB treatment inhibited osteoclastogenesis by reducing tartrate-resistant acid phosphatase (TRAP) activity and cathepsin K (CtsK) through the downregulation of nuclear factor of activated T cells cytoplasmic 1 (NFATc1) and c-fos gene expression in RANKL-induced RAW264.7 cells. Administration of MG4706 alleviated alveolar bone loss indices and reduced the gene expression of IL-1β, IL-6, MMP-8, MMP-9, and RANKL/OPG ratio in gingival tissue. In conclusion, L. rhamnosus MG4706 has the potential to alleviate periodontitis.

Ultraviolet (UV) B exposure induces wrinkle formation, collagen fiber breakdown, and transepidermal water loss (TEWL). UVB irradiation induces the expression of mitogen-activated protein kinase (MAPK), activator protein 1 (AP-1), and nuclear factor kappa B (NF-κB), which affect the expression of matrix metalloproteinases (MMP). We confirmed the effects of Latilactobacillus sakei wikim0066 (wikim0066) on UVB-irradiated Hs68 cells and HR-1 hairless mice cells. wikim0066 restored the production of type I procollagen by regulating the expression of MMP-1 and -3, MAPK, AP-1, and NF-κB in UVB-irradiated Hs68 cells and HR-1 mice. Oral administration of wikim0066 alleviates wrinkle formation, epidermal thickness, and TEWL in UVB-irradiated HR-1 hairless mice. These results indicated that wikim0066 has the potential to prevent UVB-induced wrinkle formation.