Promising role of D-amino acids in irritable bowel syndrome

Irritable bowel syndrome (IBS) is an important health care concern. Alterations in the microbiota of the gut-brain axis may be linked to the pathophysiology of IBS. Some dietary intake could contribute to produce various metabolites including D-amino acids by the fermentation by the gut microbiota. D-amino acids are the enantiomeric counterparts of L-amino acids, in general, which could play key roles in cellular physiological processes against various oxidative stresses. Therefore, the presence of D-amino acids has been shown to be linked to the protection of several organs in the body. In particular, the gut microbiota could play significant roles in the stability of emotion via the action of D-amino acids. Here, we would like to shed light on the roles of D-amino acids, which could be used for the treatment of IBS.     

中医药调控益生菌防治肺炎的研究进展＊

肺炎是呼吸系统疾病中的常见疾病，发病率高，可伴有多种并发症，严重时可危及生命健康。肺炎患者多伴有肠道菌群失调，表现为有益菌减少，且益生菌可通过“肠-肺轴”影响肺部免疫参与肺炎的发生发展。中医以“肺”与“大肠”两者之间的生理及病理关系为基础，通过整体观念和辨证论治发挥了治疗肺炎的独特的优势。近年来，许多研究表明中医药在治疗肺炎的过程中具有改善肠道微生态作用，但肺炎的中医辨证分型与肠道菌群的相关性尚不明确。本文从中医辨证分型论治肺炎的角度出发，总结不同辨证分型的肺炎与肠道菌群结构特征，阐述中医治疗肺炎过程中对于益生菌的调节作用和“证型—中药—益生菌”的对应关系。通过讨论益生菌在防治肺炎中的关键作用，展望中医辩证联合益生菌治疗肺炎的应用前景，以期为肺炎的防治提供新思路和新靶点，也为将来指导不同肺炎证型患者选择适合的中药及益生菌提供理论依据。     

New insights into necrotizing enterocolitis: From laboratory observation to personalized prevention and treatment

Background/purpose

Necrotizing enterocolitis (NEC) is a devastating disease of prematurity that develops after feeding, often without warning, and results in diffuse intestinal necrosis leading to sepsis and death in many cases. The lack of improvement in overall survival is influenced by nonspecific diagnostic modalities as well as inexact and nonpersonalized treatment strategies.

益生菌联合肠内营养对急性胰腺炎患者肠道菌群及外周血miR-155的影响

目的 探讨益生菌联合肠内营养对急性胰腺炎患者肠道菌群及外周血miR-155的影响。 方法 选取2016年6月至2018年12月河北医科大学第二医院消化内科收治的92例急性胰腺炎患者作为研究对象，根据随机数字表法分为观察组（n=46）和对照组（n=46），对照组在常规治疗基础上给予肠内营养治疗，观察组在对照组基础上给予双歧杆菌乳杆菌三联活菌片，观察两组患者治疗前后肠道菌群、炎性介质及血清miR-155变化，比较两组患者治疗后胃肠道功能恢复情况。结果 治疗后，观察组双歧杆菌、乳酸杆菌增加数量，肠球菌、大肠埃希菌减少数量，血清CRP、IL-6、IL-17、TNF-α、miR-155降低水平均显著高于对照组（P<0.05）；观察组患者胃肠生活质量量表（GIQLI）评分高于对照组，腹胀消失时间、腹痛消失时间、肠鸣音恢复时间、血清淀粉酶恢复正常时间均少于对照组（P<0.05）。结论 益生菌联合肠内营养治疗急性胰腺炎可调节肠道菌群平衡，降低血清miR-155水平，缓解炎性反应，促进肠道功能恢复。     

Stability of probiotics with antibiotics via gastric tube by simple suspension method: An in vitro study

Data on the stability of probiotics with antibiotics delivered via gastric tube using the simple suspension method (SSM) are limited. Therefore, we investigated bacterial survivability in probiotics treated with antibiotics prepared by the SSM in vitro. Probiotics and antibiotics were suspended in 20 mL of sterilized hot water (55 °C) and then 1-mL of the suspensions were taken each at 10, 60, 120, 180 and 360 min. Thereafter, the samples were inoculated on 3 media and cultured at 37 °C for 24 h. Survival of probiotic strains was measured in colony-forming units. The growth of Clostridium butyricum did not change without antibiotics at all experimental times, but in the case of Enterococcus faecium tended to increase. On the other hand, the viable bacterial number of C. butyricum was decreased significantly by treatment with cefdinir, tosufloxacin, clarithromycin, or azithromycin, but was not altered by levofloxacin, minocycline, or vancomycin. The viable bacterial number of E. faecium was significantly decreased by treatment with tosufloxacin, levofloxacin, minocycline, vancomycin, or azithromycin, and was significantly increased by clarithromycin. In conclusion, our results suggest that the efficacy of probiotic therapies might be reduced by the SSM when specific antibiotics are used. Moreover, antibiotics might inhibit probiotic growth, although some probiotics are spore-forming and have high minimum inhibitory concentrations. Additionally, early administration of non-spore-forming bacteria might be desirable. Therefore, when patients are administered therapy combining probiotics and antibiotics by the SSM, we should consider the characteristics of the probiotics and the administration times.     

Early-life stress,microbiota, and brain development: probiotics reverse the effects of maternal separation on neural circuits underpinning fear expression and extinction in infant rats

Early-life stress has pervasive, typically detrimental, effects on physical and mental health across the lifespan. In rats, maternal-separation stress results in premature expression of an adult-like profile of fear regulation that predisposes stressed rats to persistent fear, one of the hallmarks of clinical anxiety. Probiotic treatment attenuates the effects of maternal separation on fear regulation. However, the neural pathways underlying these behavioral changes are unknown. Here, we examined the neural correlates of stress-induced alterations in fear behavior and their reversal by probiotic treatment. Male Sprague-Dawley rats were exposed to either standard rearing conditions or maternal-separation stress (postnatal days [P] 2–14). Some maternally-separated (MS) animals were also exposed to probiotics (Lactobacillus rhamnosus and L. helveticus) via the maternal drinking water during the period of stress. Using immunohistochemistry, we demonstrated that stressed rat pups prematurely exhibit adult-like engagement of the medial prefrontal cortex during fear regulation, an effect that can be prevented using a probiotic treatment. The present results add to the cross-species evidence that early adversity hastens maturation in emotion-related brain circuits. Importantly, our results also demonstrate that the precocious neural maturation in stressed infants is prevented by a non-invasive probiotic treatment.     

Probiotics for intestinal decolonization of ESBL-producing Enterobacteriaceae: a randomized,placebo-controlled clinical trial

ObjectivesInfections with extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (EPE) are a major healthcare concern. Our goal was to investigate whether a probiotic mixture could be used for eradication therapy in patients with prolonged intestinal EPE carriage.MethodsWe performed a randomized, placebo-controlled, single-blinded clinical superiority trial in the south of Sweden between February 2017 and April 2019. Probiotic Vivomixx®, a mixture of 8 different living bacterial strains or placebo was given to adult outpatients intestinally colonized for at least 3 months with EPE. Patients with suspected active infections at the time of evaluation were excluded, and also those with immunosuppression, severe psychiatric disorder, drug abuse or dementia. Each patient in the probiotic arm was administered 2 sachets (9.0 × 10¹¹ live bacteria) twice daily for 2 months. The primary outcome was intestinal EPE eradication at the end of the 1-year follow-up, as shown by 3 consecutive negative EPE rectal swabs during the follow-up year. The per protocol follow-up for all patients was 1, 3, 6 and 12 months after the initiation of the intervention. ClinicalTrials.gov Identifier: NCT03860415.ResultsIn total, the target size of 80 patients were included. The median age was 68 years in both groups. The number of females in the probiotics group was 23 (58%) and in the placebo group 28 (70%). At the end of the trial, 12.5% (5 out of 40) of the patients in the probiotic group had achieved successful eradication of EPE, as defined by the primary outcome, in the intention to treat analysis. In the placebo group, 5% (2 out of 40) of the patients had achieved successful eradication of EPE (odds ratio 2.71; 95% confidence interval (CI), 0.49–14.9; p 0.24).ConclusionsSuccessful EPE eradication was observed in very few individuals. This trial did not support Vivomixx® as being superior to placebo for intestinal decolonization in adult patients with chronic colonization of EPE, but was limited in power.     

Designer probiotics: Development and applications in gastrointestinal health

Given the increasing commercial and clinical relevance of probiotics, improving their stress tolerance profile and ability to overcome the physiochemical defences of the host is an important biological goal. Herein, I review the current state of the art in the design of engineered probiotic cultures, with a specific focus on their utility as therapeutics for the developing world; from the treatment of chronic and acute enteric infections, andtheir associated diarrhoeal complexes, to targeting HIV and application as novel mucosal vaccine delivery vehicles.