Effect of Heat-Killed Lactobacillus paracasei KW3110 Ingestion on Ocular Disorders Caused by Visual Display Terminal (VDT) Loads: A Randomized, Double-Blind, Placebo-Controlled Parallel-Group Study

Abstract

Background: Visual display terminals (VDTs) emitting blue light can cause ocular disorders including eye fatigue. Some dietary constituents have been reported to be effective in improving ocular disorders while few clinical studies have been performed. We evaluated the effects of heat-killed Lactobacillus paracasei KW 3110 on improving ocular disorders and symptoms of eye fatigue among healthy human subjects with VDT loads. Methods: In vitro, the effect of L. paracasei KW3110 on blue light-induced human retinal pigment epithelial (ARPE-19) cell damage. For clinical studies, 62 healthy Japanese volunteers of 35 to 45 years of age who had experienced eye fatigue were randomized into two groups and given a placebo or L. paracasei KW3110-containing supplements for eight weeks. The primary endpoint was changes in VDT load-induced eye fatigue as determined by critical flicker frequency four and eight weeks after the start of supplementation. Results: In vitro, blue light-induced human retinal cell death was suppressed with the culture supernatants of cells treated with L. paracasei KW3110. In clinical study, the VDT load-induced reduction of critical flicker frequency tended to be milder in the L. paracasei KW3110 group when compared with the placebo group during the fourth week. Subgroup analysis classified by the degree of eye fatigue showed that the VDT load-induced reduction of critical flicker frequency was significantly better in the high-level eye fatigue subjects from the L. paracasei KW3110 group when compared with the placebo group during the fourth week (p = 0.020). Conclusions: L. paracasei KW3110 suppressed blue light-induced retinal pigment epithelial cell death. In the clinical study, ingestion of L. paracasei KW3110 had a potential to improve eye fatigue induced by VDT loads especially high levels of eye fatigue. However, further studies should be required to show more dependable clinical efficacy of L. paracasei KW3110.

Lactic acid bacterium, Lactobacillus paracasei KW3110, suppresses inflammatory stress-induced caspase-1 activation by promoting interleukin-10 production in mouse and human immune cells

“…In addition, IL-10 production was upregulated in the supernatant from KW3110-stimulated human monocytes ( Fig 6A), and both KW3110 and recombinant IL-10 protein treatments suppressed IL-1β production in LPS/ATP-stimulated cells (Fig 6B). IL-10 is a representative anti-inflammatory cytokine and is reported to be involved in inhibition of IL-1β production [23][24][25], which is consistent with our results shown in Fig 2B. KW3110 was previously reported to activate macrophages by interacting with gut immune cells and promoting cytokine production, including IL-10 [10,13,20]. It has also been reported that KW3110 suppresses the level of pro-inflammatory cytokines such as IL-1β in the serum of aged mice or the retina of blue-light exposure-induced mice [13,14].…”

“…The supernatant transferal experiment ( Fig 1B) suggested that molecules released from KW3110-treated J774A.1 cells suppressed IL-1β production in LPS/ATP-stimulated cells. KW3110 induces IL-10 production in M2 macrophages; therefore, we hypothesized that KW3110 suppresses the inflammatory response in macrophages through IL-10 induction [13,20]. KW3110 treatment dose-dependently increased IL-10 levels in J774A.1 cell supernatant (1.25 μg/mL, P = 0.002; 2.5 μg/mL, P < 0.001; 5 μg/mL, P < 0.001; Fig 2A).…”

Postbiotics—A Step Beyond Pre- and Probiotics

“…BLs can also reduce the frequency of allergic rhinitis episodes [60] and alleviate the symptoms of atopic dermatitis [61]. Finally, ingesting heat-killed Lactobacillus paracasei may be applicable in reducing the symptoms of dry eye syndrome, which primarily arises from the long-term, repetitive exposure to blue light emitted by LED screens [62].…”

A Novel Botanical Combination Attenuates Light-Induced Retinal Damage through Antioxidant and Prosurvival Mechanisms

“…It is frequently associated with situations where the accommodative and vergence processes are more intense, exemplified by long-period looking at video display units (VDUs), e.g., computer, mobile phone, and iPad [1]. Blue light emitted from VDUs can damage retinal cells, which has been reported to be related to eye fatigue [2][3][4]. With a global increasing rate of asthenopia paralleled with more frequently used VDUs at different stages of life [1,[5][6][7], it is important to develop an effective method to mitigate asthenopia-related manifestations and curb the progressing of retinal damage.…”