Ralstonia solanacearum differentially modulates soil physicochemical properties and rhizospheric bacteriome of resistant and susceptible tobacco cultivars.

Ralstonia solanacearum is a devastating soilborne pathogen which poses significant yield and economic losses to tobacco production globally. The impact of R. solanacearum on rhizosphere bacteriome and soil physicochemical characteristics in resistant and susceptible tobacco cultivars is poorly understood. This study aims to determine the effect of R. solanacearum on soil physicochemical parameters and rhizosphere bacteriome of resistant (K326) and susceptible (Hongda) tobacco cultivars at various growth stages. Results demonstrated that the contents of available potassium and phosphorus, as well as soil pH were significantly increased in K326 soils (CK and T2) compared with Hongda (T1) after 21, 42, and 63 days post-inoculation (dpi) of R. solanacearum except for available nitrogen which showed an opposite trend. The qPCR results showed a significant decrease in R. solanacearum population in rhizosphere of K326 (T2) compared to the Hongda (T1) at 21 and 63 dpi than that after 42 dpi. The rhizosphere bacteriome analysis through 16S rRNA amplicon sequencing revealed that rhizosphere bacterial community composition was significantly different between two tobacco cultivars (Hongda and K326) and this effect was more prominent after 63 dpi (93 days after post-transplantation), suggesting that each cultivar recruits a unique set of bacterial communities. There was no obvious difference observed in the rhizosphere bacteriome of CK (K326) and T2 (K326), which might be attributed to the same genetic makeup and inherent resistance of K326 to bacterial wilt infection. Analysis of co-occurrence networks revealed that the microbial network in T1 (Hongda) was more complex than those in T2 (K326) and CK (K326), while the networks in CK and T2 were almost identical. The present research highlights the time-course relationship between environmental factors and rhizosphere bacteriome of tobacco cultivars showing different levels of resistance against R. solanacearum. Conclusively, studying the plant-soil-microbe interaction system in susceptible and resistant tobacco cultivars may enable us to develop effective integrated disease control plans for the healthy production of tobacco crops.

Correlations Between Endocrine Hormones and Cognitive Function in Patients with Obesity: a Cross-sectional Study.

BACKGROUND: Obesity not only affects physical and mental conditions, but also influences cognitive function. Endocrine hormones may influence the risk of obesity and severe obesity. Our study investigated the influences of changes in levels of endocrine hormones on cognitive function in patients with obesity and severe obesity. METHODS: We used the MATRICS Consensus Cognitive Battery (MCCB) to evaluate cognitive function in the groups of healthy control (HC), obesity (OB), and severe obesity (SOB). We detected the levels of endocrine hormones and cortisol at 8:00 am in the three groups. We statistically analyzed differences in cognitive function and levels of endocrine hormones among the three groups, and performed linear correlation analysis of cortisol level and cognitive function. Using mediation analysis, we assessed the influences of body mass index (BMI) on endocrine levels and cognitive function. RESULTS: Our findings revealed that OB and SOB groups exhibited a lower level of cortisol than HC group. Among the three groups, we found significant differences in verbal learning (F = 4.433, P = 0.014), social cognition (F = 4.778, P = 0.010), and total cognition (F = 2.989, P = 0.008). After post hoc Bonferroni correction, we noted that SOB group had worse scores in the above-mentioned three areas than OB and HC groups. Moreover, except for working memory and visual cognition, we identified that the degree of cognitive impairment in SOB group was more severe than that in OB group. In our study, mediation analysis showed a mediating effect of BMI on cortisol level and verbal learning. We also found correlations between cortisol level and attention/alertness (r = 0.277, P = 0.003), between cortisol level and verbal learning (r = 0.205, P = 0.030), and between BMI and verbal learning (r = - 0.192, P = 0.043). CONCLUSION: In our study, patients in both OB and SOB groups experienced a widespread cognitive impairment. We also found that patients with severe obesity had more severe cognitive impairment. Cognitive impairment could be mediated by abnormal cortisol metabolism, and BMI could be a mediating factor in regulation of cortisol level.

Grape seed proanthocyanidin reverses pulmonary vascular remodeling in monocrotaline-induced pulmonary arterial hypertension by down-regulating HSP70.

Heat shock protein 70 (HSP70) is a molecular chaperone which has a low content in cytoplasm under normal physiological conditions. A higher intracytoplasmic HSP70 level can be observed in pulmonary arterial smooth muscle cell (PASMC) in pulmonary arterial hypertension (PAH), and this up-regulation can promote pho-IκBα expression, which is an NF-κB signaling pathway inhibitor. NF-κB signaling pathway up-regulation can promote PASMC proliferation and pulmonary vascular remodeling in PAH, resulting in elevation of pulmonary pressure and the subsequent right heart failure caused by right ventricular hypertrophy. Grape seed proanthocyanidin (GSP) is effective in vascular protection and several tumor treatments, and its effect on PAH treatment remains to be elucidated. In this study, we made observations and contrasts in monocrotaline(MCT) -induced PAH rats, and found decrease in mPAP, PVR and RVHI after GSP administration. Our study also proved GSP's effect on down-regulating the intracytoplasmic HSP70 content both in cellular and animal levels. The results indicate a possible mechanism of GSP reversing pulmonary vascular remodeling by down-regulating HSP70, and this change may influence pho-IκBα expression. Therefore, inhibition of NF-κB signaling pathway caused by GSP can lead to inhibition of PASMC proliferation in PAH.