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Gut bacteria and gut barrier plays important roles in body homeostasis. Ciprofloxacin (CPFX) is widely used to treat bacterial infections. However, whether high dosage of CPFX has side effects on gut barrier integrity is still unclear. Our results indicated that the High CPFX treatment (1 mg/ml) caused weight loss, nervousness, anorexia, and increased apoptosis cells in gut, but less influence was observed in the Low CPFX group (0.2 mg/ml). Meanwhile, the High CPFX treatment impaired tight junction molecules Ocln/ZO-1 level and down-regulated antibacterial genes expression (reg3γ, pla2g2α and defb1). Further, the High CPFX treatment increased pro-inflammatory cytokine IL-1β in intestinal tract, decreased IL-17A of duodenum but increased IL-17A of colon at day 37. In addition, the gut bacterial diversity and richness behaved significantly loss regarding CPFX treatment, especially in the High CPFX group during the experiment. Indole exhibited sharply decline in both Low and High CPFX groups at day 7, and the High CPFX mice needed longer time on restoring indole level. Meanwhile, CPFX treatment strongly decreased the concentrations of butyric acid and valeric acid at day 1. Correlation analysis indicated that the linked patterns between the key bacteria (families Bacteroidales_S247, Ruminococcaceae and Desulfovibrionaceae) and metabolites (indole and butyric acid) were disturbed via the CPFX treatment. In conclusion, the High CPFX treatment impaired the gut barrier with the evidence of reduced expression of tight junction proteins, increased apoptosis cells and inflammatory cells, decreased the bacterial diversity and composition, which suggesting a proper antibiotic-dosage use should be carefully considered in disease treatment.  相似文献   
3.
The gut microbiota and the bile acid pool play pivotal roles in maintaining intestinal homeostasis. Bile acids are produced in the liver from cholesterol and metabolized in the intestine by the gut microbiota. Gut dysbiosis has been reported to be associated with colorectal cancer. However, the interplay between bile acid metabolism and the gut microbiota during intestinal carcinogenesis remains unclear. In the present study, we investigated the potential roles of bile acids and the gut microbiota in the cholic acid (CA; a primary bile acid)‐induced intestinal adenoma‐adenocarcinoma sequence. Apc min/+ mice, which spontaneously develop intestinal adenomas, were fed a diet supplemented with 0.4% CA for 12 weeks. Mice that were fed a normal diet were regarded as untreated controls. In CA‐treated Apc min/+ mice, the composition of the gut microbiota was significantly altered, and CA was efficiently transformed into deoxycholic acid (a secondary bile acid) by the bacterial 7α‐dehydroxylation reaction. The intestinal adenoma‐adenocarcinoma sequence was observed in CA‐treated Apc min/+ mice and was accompanied by an impaired intestinal barrier function and IL‐6/STAT3‐related low‐grade inflammation. More importantly, microbiota depletion using an antibiotic cocktail globally compromised CA‐induced intestinal carcinogenesis, suggesting a leading role for the microbiota during this process. Overall, our data suggested that the crosstalk between bile acids and the gut microbiota mediated intestinal carcinogenesis, which might provide novel therapeutic strategies against intestinal tumor development.  相似文献   
4.
Objectives: Increases in astrocytes and one of their markers, glial fibrillary acidic protein (GFAP) have been reported in the brains of patients with Alzheimer’s disease (AD). N-3 polyunsaturated fatty acids (PUFA) modulate neuroinflammation in animal models; however, their effect on astrocytes is unclear.

Methods: Fat-1 mice and their wildtype littermates were fed either a fish oil diet or a safflower oil diet deprived of n-3 PUFA. At 12 weeks, mice underwent intracerebroventricular infusion of amyloid-β 1-40. Astrocyte phenotype in the hippocampus was assessed at baseline and 10 days post-surgery using immunohistochemistry with various microscopy and image analysis techniques.

Results: GFAP increased in all groups in response to amyloid-β, with a greater increase in fish oil-fed mice than either fat-1 or wildtype safflower oil-fed mice. Astrocytes in this group were also more hypertrophic, suggesting increased activation. Both fat-1- and fish oil-fed mice had greater increases in branch number and length in response to amyloid-β infusion than wildtype safflower animals.

Conclusion: Fish oil feeding, and to a lesser extent the fat-1 transgene, enhances the astrocyte activation phenotype in response to amyloid-β 1-40. Astrocytes in mice fed fish oil were more activated in response to amyloid-β than in fat-1 mice despite similar levels of hippocampal n-3 PUFA, which suggests that other fatty acids or dietary factors contribute to this effect.  相似文献   

5.
Beneficial therapeutic effects of phenolic acids have been proven in various research projects including in vivo and in vitro studies. Gentisic acid (GA) is a phenolic acid that has been associated with useful effects on human health, such as antiinflammatory, antigenotoxic, hepatoprotective, neuroprotective, antimicrobial, and especially antioxidant activities. It is an important metabolite of aspirin and also widely distributed in plants as a secondary plant product such as Gentiana spp., Citrus spp., Vitis vinifera, Pterocarpus santalinus, Helianthus tuberosus, Hibiscus rosa‐sinensis, Olea europaea, and Sesamum indicum and in fruits such as avocados, batoko plum, kiwi fruits, apple, bitter melon, black berries, pears, and some mushrooms. This study was undertaken to review the pharmacological effects, pharmacokinetic properties as well as toxicity and pharmaceutical applications of GA.  相似文献   
6.
丹参干燥前后,新鲜和干燥丹参中酚酸成分含量有显著性差异,即在干燥过程中随脱水增加,丹参酚酸含量显著增加。为探究丹参干燥前后游离型和结合型酚酸含量的差异及转化,该实验对丹参酚酸水解方法、水解产物、水解规律等进行研究,采用UPLC测定丹参结合型酚酸4种主要水解产物丹参素、咖啡酸二聚体(SMND-309)、咖啡酸、甘西鼠尾草酸甲(原紫草酸)以及丹参中3种主要游离酚酸成分(迷迭香酸、紫草酸和丹酚酸B)的含量。结果显示,丹参酚酸的碱水解效果显著优于酸水解,优选的碱水解条件为用含有1%抗坏血酸的2 mol·L-1氢氧化钠溶液于70℃水解4 h;游离酚酸和结合酚酸的水解产物相同;新鲜丹参中游离酚酸含量较低,结合酚酸含量较高,而干燥丹参却相反。提示丹参生长过程中已积累储存了大量的结合型酚酸,主要以酯键与细胞壁多糖结合形成了不溶性酚酸,常规方法不易检出,在干燥脱水过程中,结合型酚酸或在相关酶的作用下转化生成大量的游离酚酸。  相似文献   
7.

Background and Aims

Diet is known to play a decisive role in the development of coronary heart disease (CHD). One factor believed to decrease lifetime risk of CHD is the consumption of omega-3 fatty acids. Yet, conclusive evidence regarding the potential cardioprotective effects of fatty acids is far from being reached. The present study aimed to provide further evidence on the association of serum fatty acid profiles with CHD risk.

Methods and Results

The CARdio-vascular Disease, Living and Ageing in Halle study (CARLA study) is an observational cohort study comprising an older adult's general population with a high level of cardiovascular risk factors. In a matched case–control design the serum fatty acid concentrations of 73 subjects with an incident fatal or nonfatal CHD event were compared to 146 controls matched for sex and age. Our data show that the participants of the CARLA study are underserved in unsaturated fatty acids with respect to current dietary recommendations. In addition, the ratio of omega-6 to omega-3 fatty acids was determined to be 8:1 which underlines the consumption of a Western-style diet enriched in omega-6 fatty acids. There were no significant differences in fatty acid patterns between cases and controls. Thus, no clear association of particular serum fatty acid levels with cardiovascular risk was found.

Conclusion

Our results support the conclusion that in populations with a homogenous low level of omega-3 polyunsaturated fatty acids consumption, serum fatty acid levels are not associated with CHD risk.  相似文献   
8.
9.
Background and aimsThe metabolic syndrome (MetS) is a cluster of coexisting cardiovascular risk factors. The role of specific dietary fats was reemphasized by dietary recommendations. This systematic review aims to assess evidence for the effect of dietary fat intake on MetS occurrence and reversion in adults.Methods and ResultsThe MEDLINE database was used to search the existing literature. We included observational studies that analyzed dietary fat intake in adults with MetS and clinical trials that compared the effects of different dietary fat diets on MetS and/or its components. Thirty articles were selected (14 observational and 16 clinical trials), and we included information of dietary fat and fatty acids as well as MetS, body mass index, cholesterol, hypertension, and diabetes in adults. SFA intake was found to be positively associated with MetS components. Most of the observational reviewed studies found beneficial associations between MUFA and PUFA (including n-3 and n-6 subtypes) intake and MetS components. Clinical trials also supported the benefits of MUFA- or PUFA-enriched diets (including low-fat diets) in reducing MetS.ConclusionsThe effects of dietary SFAs on MetS will be influenced by other specific nutrients. Replacement of SFA by MUFA and PUFA has been associated with a decrease in MetS. Dietary recommendations should emphasize on different qualities of fat intake, not only to reduce total fat intake, to obtain health benefits in adults.  相似文献   
10.
Type 2 diabetes mellitus (T2DM) is a complicated metabolic disease and has become one of the significant medical problems worldwide. Researchers aim to provide fine-tuned treatment for T2DM with minimal exposed side effects. Nutraceuticals are compounds or materials and emerging evidence suggests that the use of nutraceuticals has recently been recognized as a promising option for the prevention and management of T2DM, such as probiotics and prebiotics, Vitamin D, n-3 long-chain polyunsaturated fatty acids, and Plant-derived nutraceuticals. This review attempts to show the most popular nutraceuticals and review their effects and possible mechanisms in the prevention or glycemic control of T2DM.  相似文献   
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