Decrease of ‘health‑benefiting’ microbes and increase of pathogenic bacteria (a condition termed dysbiosis) in intensive care unit patients is considered to induce or aggravate sepsis (gut‑origin sepsis). Orally administered probiotics have been effective in the prevention of nosocomial infections. However, the mechanisms of probiotic‑induced anti‑infection and anti‑sepsis remain to be explored. In the present study, 4‑week‑old C57BL6 mice were orally administrated with Lactobacillus rhamnosus GG (LGG) or normal saline (control) 4 weeks prior to cecal ligation and puncture (CLP). A subset of the mice were sacrificed at 24 h post‑CLP, and the others were used for survival studies. Ileum tissues, blood and fecal samples were collected. The survival rate of septic mice pretreated with LGG was significantly improved compared with untreated mice. The levels of inflammatory cytokines were reduced in LGG‑pretreated septic mice. A decrease of colonic proliferation and epithelial tight junctions and an increase of colonic apoptosis were observed in control septic CLP+saline mice. LGG pretreatment reversed the colonic proliferation, apoptosis and expression of tight junction proteins to the levels of the sham group. LGG pretreatment improved the richness and diversity of intestinal microbiota in septic mice. The principal coordinates analysis clustering plots revealed a significant separate clustering in microbiota structure between three groups. Bacteria associated with energy consumption, including Bacteroidetes, with opportunistic infection, including Proteobacteria, Staphylococcaceae and Enterococcaceae, lipopolysaccharide producers, including Enterobacteriaceae, and facultative anaerobes, such as Bacteroidaceae and Erysipelotrichaceae, increased in septic mice. By contrast, bacteria associated with energy harvest, including Firmicutes, intestinal barrier function regulators, including Akkermansia, hepatic function regulators, including Coprococcus and Oscillospira, and obligate anaerobes, including Prevotellaceae, decreased in septic mice. With LGG pretreatment, the sepsis‑induced microbiota dysbiosis was reversed. The present results elucidated the potential mechanism of LGG treatment in sepsis, by improving intestinal permeability and modulating microbiota dysbiosis.

Alzheimer’s disease (AD) is the most common cause of dementia characterized by amyloid-β (Aβ) deposition, tau hyperphosphorylation, and neuroinflammation. Naringenin (NRG), a natural flavonoid widely present in citrus fruits, has been reported can penetrate the blood-brain barrier and exert anti-inflammatory effects in the central nervous system. Here, we investigate the protective effects of long-term NRG treatment on AD. The novel object recognition test and Morris water maze test reveal that NRG treatment can improve the learning and memory ability of APP/PS1 mice. Besides, we find that NRG can significantly reduce Aβ deposition, microglial and astrocytic activation, and pro-inflammatory cytokine levels in APP/PS1 mice. Results further show that NRG effectively decreases pro-inflammatory cytokines in LPS/Aβ-stimulated BV2 cells. Lastly, the molecular mechanistic study reveals that NRG attenuates neuroinflammatory responses via inhibition of the MAPK signaling pathway in vivo and in vitro. Overall, NRG may emerge as a promising compound for the prevention and treatment of AD.

Disruption of the intestinal barrier is both the cause and result of sepsis. The proliferation and differentiation of intestinal stem cells (ISCs) promote the regenerative nature of intestinal epithelial cells, repairing the injured intestinal mucosal barrier; however, it is uncertain whether the recovery effects mediated by the ISCs are related to the gut microbiota. This research found that the survival rate of septic mice was improved with a Lactobacillus rhamnosus GG (LGG) treatment. Furthermore, an increased proliferation and decreased apoptosis in colon epithelial cells were observed in the LGG-treated septic mice. In vitro, we found that a LGG supernatant was effective in maintaining the colonoid morphology and proliferation under the damage of TNF-α. Both in the mice colon and the colonoid, the LGG-induced barrier repair process was accompanied by an increased expression of Lgr5⁺ and lysozyme⁺ cells. This may be attributed to the upregulation of the IL-17, retinol metabolism, NF-kappa B and the MAPK signaling pathways, among which, Tnfaip3 and Nfkbia could be used as two potential biomarkers for LGG in intestinal inflammation therapy. In conclusion, our finding suggests that LGG protects a sepsis-injured intestinal barrier by promoting ISCs regeneration, highlighting the protective mechanism of oral probiotic consumption in sepsis.

To evaluate evidence for the role of probiotic supplementation in enhancing natural killer (NK) cell function in healthy elderly individuals. Five electronic databases were searched, and references of included articles and eligible reviews up to December 2019, with English language and human subject restrictions, were examined. Two independent reviewers identified randomized control trials (RCTs) of probiotic supplementation influencing NK cell function in healthy elderly individuals, assessed the quality of every article, and extracted data for subsequent meta-analysis. We identified six eligible trials including 364 healthy elderly subjects. Trials were heterogeneous in study design and probiotic supplementation (including genus, strain, dose, and duration). Five trials used Lactobacillus interventions alone or in combination with Bifidobacterium. Only one trial focused on Bacillus coagulans. The duration of supplementation ranged from 3 to 12 weeks, and the doses, from 1 × 10⁹ to 4 × 10¹⁰ colony-forming units. Pooling data of eligible trials showed that probiotics significantly (P < 0.05) increased NK cell activity in healthy elderly individuals (standardized mean difference = 0.777, 95% confidence interval: 0.187‒1.366, P = 0.01, I² = 84.6%). Although we obtained a significant outcome, the data do not provide convincing evidence for associations between probiotic supplementation and enhancement of NK cell function, given the small final number and very large heterogeneity. More RCTs with sufficient sample sizes and long-term follow-up are needed to focus on optimal probiotic dose, species, and duration of supplementation for healthy elderly individuals.

Background: Ultrasound is emerging as an effective method for measuring muscle mass in elderly people. It has been applied in numerous studies to obtain measurement of lower limbs. The study aims to explore the relationship between sarcopenia and ultrasound measurements of biceps brachii.