Lactobacillus plantarum (L. plantarum) is a well-known probiotic among the ingested-microorganism probiotics (i.e., ingested microorganisms associated with beneficial effects for the host). However, few studies have examined the effects of L. plantarum TWK10 (LP10) supplementation on exercise performance, physical fatigue, and gut microbial profile. Male Institute of Cancer Research (ICR) strain mice were divided into three groups (n = 8 per group) for oral administration of LP10 for six weeks at 0, 2.05 × 10⁸, or 1.03 × 10⁹ colony-forming units/kg/day, designated the vehicle, LP10-1X and LP10-5X groups, respectively. LP10 significantly decreased final body weight and increased relative muscle weight (%). LP10 supplementation dose-dependently increased grip strength (p < 0.0001) and endurance swimming time (p < 0.001) and decreased levels of serum lactate (p < 0.0001), ammonia (p < 0.0001), creatine kinase (p = 0.0118), and glucose (p = 0.0151) after acute exercise challenge. The number of type I fibers (slow muscle) in gastrocnemius muscle significantly increased with LP10 treatment. In addition, serum levels of albumin, blood urea nitrogen, creatinine, and triacylglycerol significantly decreased with LP10 treatment. Long-term supplementation with LP10 may increase muscle mass, enhance energy harvesting, and have health-promotion, performance-improvement, and anti-fatigue effects.

Probiotic supplements are potential therapeutic agents for age-related disorders due to their antioxidant and anti-inflammatory properties. However, the effect of probiotics on age-related brain dysfunction remains unclear. To investigate the effects of Lactobacillus paracasei PS23 (LPPS23) on the progression of age-related cognitive decline, male and female senescence-accelerated mouse prone 8 (SAMP8) mice were divided into two groups (n = 6 each): the control and PS23 groups. From the age of 16 weeks, these groups were given saline and LPPS23, respectively, because SAMP8 mice start aging rapidly after four months of age. After 12 weeks of treatment, we evaluated the effect of LPPS23 by analyzing their appearance, behavior, neural monoamines, anti-oxidative enzymes, and inflammatory cytokines. The PS23 group showed lower scores of senescence and less serious anxiety-like behaviors and memory impairment compared to the control group. The control mice also showed lower levels of neural monoamines in the striatum, hippocampus, and serum. Moreover, LPPS23 induced the anti-oxidative enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx). Higher levels of tumor necrosis factor (TNF)-α and monocyte chemotactic protein-1 (MCP1) and lower levels of interleukin (IL)-10 indicated that LPPS23 modulated the inflammation. Our results suggest that LPPS23 supplements could delay age-related cognitive decline, possibly by preventing oxidation and inflammation and modulating gut–brain axis communication.

Background: Changes in the gene expressions for tumor necrosis factor-α (TNF-α) and/or interleukin-1β (IL-1β) during tinnitus have not been previously reported. We evaluated tinnitus and mRNA expression levels of TNF-α, IL-1β, and N-methyl D-aspartate receptor subunit 2B (NR2B) genes in cochlea and inferior colliculus (IC) of mice after intraperitoneal injections of salicylate. Methods: Forty-eight 3-month-old male SAMP8 mice were randomly and equally divided into two groups: salicylate-treated and saline-treated. All mice were trained to perform an active avoidance task for 5 days. Once conditioned, an active avoidance task was performed 2 hours after daily intraperitoneal injections of saline, either alone or containing 300 mg/kg sodium salicylate. Total numbers of times (tinnitus score) the mice climbed during the inter-trial silent period for 10 trials were recorded daily for 4 days (days 7 to 10), and then mice were euthanized for determination of mRNA expression levels of TNF-α, IL-1β, and NR2B genes in cochlea and IC at day 10. Results: Tinnitus scores increased in response to daily salicylate treatments. The mRNA expression levels of TNF-α increased significantly for the salicylate-treated group compared to the control group in both cochlea (1.89 ± 0.22 vs. 0.87 ± 0.07, P < 0.0001) and IC (2.12 ± 0.23 vs. 1.73 ± 0.22, p = 0.0040). mRNA expression levels for the IL-1β gene also increased significantly in the salicylate group compared to the control group in both cochlea (3.50 ± 1.05 vs. 2.80 ± 0.28, p < 0.0001) and IC (2.94 ± 0.51 versus 1.24 ± 0.52, p = 0.0013). Linear regression analysis revealed a significant positive association between tinnitus scores and expression levels of TNF-α, IL-1β, and NR2B genes in cochlea and IC. In addition, expression levels of the TNF-α gene were positively correlated with those of the NR2Bgene in both cochlea and IC; whereas, the expression levels of the IL-1β gene was positively correlated with that of the NR2B gene in IC, but not in cochlea. Conclusion: We conclude that salicylate treatment resulting in tinnitus augments expression of the TNF-α and IL-1β genes in cochlea and IC of mice, and we suggest that these proinflammatory cytokines might lead to tinnitus directly or via modulating the NMDA receptor.

Hyaluronan (HA) is present in all connective tissues and organs, including the skin and joint fluid. However, few clinical trials have comprehensively evaluated the impacts of oral HA on skin conditions, including wrinkles and moisturization. In this study, we conducted a placebo-controlled, randomized, double-blind trial of daily HA (120 mg) intake for 12 weeks in 40 healthy Asian men and women (aged 35–64 years). Skin condition was determined by the evaluation of wrinkles, stratum corneum water content, the amount of transepidermal water loss, elasticity, and through image analysis. After 12 weeks, skin condition was significantly improved in terms of wrinkle assessment, stratum corneum water content, transepidermal water loss, and elasticity in the HA group compared to the placebo group. Regarding the percentage change from baseline, wrinkle assessment, stratum corneum water content, and skin elasticity were significantly improved in the HA group versus the placebo group after 8 and 12 weeks of ingestion. The present findings indicate that oral ingestion of HA may suppress wrinkles and improve skin condition.

The present study was carried out to explore the effects of oolong and green teas on improving the memory deficits and brain pathological changes in senescence accelerated-prone mice P8 (SAMP8). Six-month-old mice were supplied with oolong tea, green tea or water as the sole drinking fluid for 16 wk. The memory ability of mice was evaluated by passive and active avoidance tests, while the extent of the brain degeneration was measured by the spongiosis grades and the lipofuscin percentage in the hippocampus. The total grading score and serum biochemical levels were also measured. The results indicated that the mice supplemented with the oolong and green tea drinks reversed the cognitive impairment, lessened the spongy degeneration and lipofuscin, and increased the serum Trolox equivalent antioxidant capacity more than the control group. The total grading score of the oolong tea group was lower than that of the control group in male mice, whereas it did not differ among female groups. No differentiations in the concentrations of total cholesterol, triglyceride, glucose, iron or hemoglobin were observed among three drink groups. In conclusion, oolong and green teas could reduce the deteriorations of cognitive ability, brain degenerative changes and aging process in SAMP8, probably through the potent antioxidative activity of the tea.

(1) Background: An age-related cognitive decline is commonly affecting the life of elderly with symptoms involved in progressive impairments to memory and learning. It has been proposed that probiotics could modulate age-related neurological disorders via the gut–brain axis. (2) Methods: To investigate the anti-aging effect of probiotic Lactobacillus plantarum GKM3, both survival tests and cognitive experiments were conducted in the SAMP8 mice model. The six-month-old SAMP8 (n = 20 in each gender) were fed with probiotic GKM3 at a dosage of 5.1 × 10⁹ and 1.0 × 10⁹ cfu/ kg B.W./day until their natural death. Then, the life span was investigated. Three-month-old SAMP8 (n = 10 in each gender) were administered GKM3 for 14 weeks. Then, the behavior tests and oxidation parameters were recorded. (3) Results: GKM3 groups showed significantly increased latency in the passive avoidance test and time of successful avoidance in the active avoidance test. The TBARS and 8-OHdG from mice brains also showed a significant reduction in the groups treated with GKM3. In addition, lower accumulation of the amyloid-β protein was found in SAMP8 mice brains with the supplement of GKM3. (4) Conclusions: These results indicated that L. plantarum GKM3 delayed the process of aging, alleviated age-related cognitive impairment, and reduced oxidative stress.