Trimethylamine-N-oxide (TMAO) is a gut microbial metabolite that promotes Alzheimer's disease (AD) progression. Given that probiotics can alleviate AD symptoms by inhibiting the synthesis of TMAO, here we investigated the correlation between TMAO and cognitive deterioration by measuring TMAO levels in the plasma of choline-treated APP/PS1 mice (an AD mouse model) with and without probiotic treatments. We found that declines in L. plantarum in the gut were associated with cognitive impairment. Moreover, 12-weeks of treatment with memantine plus L. plantarum ameliorated cognitive deterioration, decreased Αβ levels in the hippocampus, and protected neuronal integrity and plasticity. These effects were accompanied by reductions in TMAO synthesis and neuroinflammation. These experiments demonstrate that L. plantarum augments the beneficial therapeutic effects of memantine treatment in APP/PS1 mice by remodeling the intestinal microbiota, inhibiting the synthesis of TMAO, and reducing clusterin levels. Our results thus highlight intestinal microbiota as a potential therapeutic target to decrease the risk of AD.

We investigated the neuroprotective effects of baicalin and the role of gut microbiota in a mouse model of cerebral ischemia-reperfusion injury. Repeated cerebral ischemia-reperfusion significantly increased plasma levels of trimethylamine (TMA), trimethylamine-N-oxide (TMAO), and clusterin (a neuroinflammation biomarker). These changes correlated with cognitive decline; short-term memory deficits; abnormal long term potentiation (LTP); decreased functional connectivity (FC) between various brain regions; reduced plasticity and dendritic spine density in the hippocampus; increased levels of the pro-inflammatory cytokines IL-1β, IL-6, and TNFα; and altered the gut microbial composition. Treatment with 50-100 mg/Kg baicalin for 7 days after cerebral ischemia-reperfusion significantly restored normal plasma levels of TMA, TMAO, and clusterin. Baicalin treatment also suppressed neuroinflammation, remodeled the gut microbial composition back to normal, and improved cognition, memory, LTP, cerebral FC, and hippocampal neuronal plasticity. The neuroprotective effects of baicalin were diminished when mice undergoing repeated cerebral ischemia-reperfusion were pretreated with broad-spectrum antibiotics to deplete gut microbial populations. This suggests the neuroprotective effects of baicalin in cerebral ischemia-reperfusion injury are mediated by the gut microbiota. It thus appears that baicalin ameliorates neuropathology in a repeated cerebral ischemia-reperfusion model mice by remodeling the gut microbiota.

Colon cancer is the second most common cancer in developed countries. Activated platelets play a key role in inflammation and atherothrombosis, with mean platelet volume (MPV) is an early marker of platelet activation. The aim of the study was to clarify the relevance of MPV in patients with colon cancer. We measured MPV levels in 128 patients with colon cancer before and after surgery, and 128 controls matched for age, gender, body mass index (BMI) and smoking status. The odds ratios (ORs) and 95% confidence intervals (CIs) for colon cancer were calculated using multivariate logistic regression analyses across MPV quartiles. Patients with colon cancer had higher MPV compared with controls. Surgical tumor resection resulted in a significant decrease in MPV levels (11.4 fL vs 10.7 fL; p<0.001). A positive correlation between MPV and tumor-nodule-metastases (TNM) stage was found. Furthermore, after adjusting for other risk factors, the ORs (95%CIs) for colon cancer according to MPV quartiles were 1.000, 2.238 (1.014-4.943), 3.410 (1.528-7.613), and 5.379 (2.372-12.198), respectively. The findings show that patients with colon cancer have higher MPV levels compared with controls, and these are reduced after surgery. In addition, MPV was found to be independently associated with the presence of colon cancer. Further studies are warranted to assess the utility of MPV as a novel diagnostic screening tool for colon cancer.

Platelets play a multifaceted role in cancer progression and metastasis. Mean platelet volume (MPV) and platelet distribution width (PDW) are commonly used platelet parameters from routine blood test. The aim of the present study was to investigate the correlation between platelet indices and prognosis in patients with non-small cell lung cancer (NSCLC). A total of 270 patients who were diagnosed with NSCLC between January 2009 and December 2009 were retrospectively analyzed. Patients’ characteristics and hematologic tests data at initial diagnosis were collected. The overall survival rate was estimated using Kaplan-Meier method. The prognostic analysis was carried out with univariate and multivariate Cox regressions model. Reduced PDW was significantly correlated with T stage, N stage, TNM stage, and histological type of the disease. Moreover, survival analysis showed that the overall survival of patients with PDW ≥ 16.3% was significantly longer than that of those with PDW < 16.3% (P < 0.001). In multivariate Cox regression model, age, sex, TNM stage, and PDW were identified as independent prognostic factors for overall survival (for PDW, P < 0.001). In conclusion, reduced PDW is an unfavorable predictive factor of NSCLC patient survival. Further studies are warranted.

Altered mean platelet volume (MPV) is implicated in several malignancies. However, the clinicopathological significance and prognostic value of MPV in colorectal cancer (CRC) is still elusive. The purpose of this study was to elucidate the predictive significance of MPV in CRC. The retrospective study recruited 509 consecutive CRC patients between January 2009 and December 2009. The relationships between MPV and clinicopathological characteristics were analyzed. Kaplan-Meier method and Cox regression were used to evaluate the prognostic impact of MPV. Of the 509 CRC patients, high MPV levels were detected in 150 (29.5%) patients. Elevated MPV was associated with tumor differentiation (p < 0.001). Patients with increased MPV had poor overall survival compared with those with normal level (60.0% vs. 83.6%, log-rank test, p = 0.035). Cox regression analysis showed that MPV was an independent prognostic factor in CRC (HR = 1.452, 95% CI = 1.118–1.884, p = 0.005). In conclusion, MPV is easily available in routine blood test. Elevated MPV might act as a marker of prognosis and therapeutic target for CRC.