Different effects of acute and chronic oxidative stress on the intestinal flora and gut-liver axis in weaned piglets

IntroductionOxidative stress plays a pivotal role in modulating the balance of intestinal flora and the gut-liver axis, while also serving as a key determinant of the growth potential of weaned piglets. However, few studies have subdivided and compared acute and chronic oxidative stress.MethodsIn this study, an intestinal model of acute oxidative stress in weaned piglets using paraquat (PQ) and a chronic oxidative stress model using D-galactosa in weaned piglets were conducted. And we further systematically compare their effects.ResultsBoth acute and chronic oxidative stress models impaired intestinal barrier function and liver function. Chronic stress caused by D-galactose can result in severe redox dysregulation, while acute stress caused by paraquat can lead to inflammation and liver damage. Additionally, the components involved in the CAR pathway were expressed differently. Chronic or acute oxidative stress can reduce the diversity and composition of intestinal flora. In the PQ group, the richness of Mogibacterium and Denitratisoma improved, but in the D-gal group, the richness of Catenisphaera and Syntrophococcus increased.DiscussionNot only does this research deepen our understanding of the effects of acute and chronic oxidative stress on intestinal functions, but it also characterizes characteristic changes in the gut flora, potentially identifying novel therapeutic targets and opening new avenues for future research

Long-Term l-Serine Administration Reduces Food Intake and Improves Oxidative Stress and Sirt1/NFκB Signaling in the Hypothalamus of Aging Mice

Serine has recently been shown to reduce oxidative stress and inflammation, which, when occurring in the hypothalamus, contribute to age-related obesity. To explore whether long-term serine administration reduces oxidative stress and body weight in aging mice, various concentrations of l-serine dissolved in water were administered to 18-month-old C57BL/6J mice for 6 months. The results showed that the administration of 0.5% (w/v) l-serine significantly reduced food intake and body weight gain during the experiment. Moreover, the administration of 0.5% l-serine decreased the concentrations of leptin, malondialdehyde, interleukin-1β, and interleukin-6, while it increased those of superoxide dismutase and glutathione, in both the serum and hypothalamus. Reactive oxygen species and the activity of nicotinamide adenine dinucleotide phosphate oxidase were reduced in the hypothalamus of aging mice treated with l-serine as compared with untreated control mice. Additionally, the expression of the leptin receptor increased while the levels of neuropeptide Y and agouti-related protein decreased in mice that had been treated with 0.5% l-serine. The expression of Sirt1 and phosphorylated signal transducers and activators of transcription 3 (pSTAT3) increased, while that of phosphorylated NFκB decreased in the mice treated with 0.5% l-serine. These results indicated that long-term l-serine administration reduces body weight by decreasing orexigenic peptide expression and reduces oxidative stress and inflammation during aging in mice, possibly by modulating the Sirt1/NFκB pathway. Thus, l-serine has the potential to be used in the prevention of age-related obesity

An Alternative to Current Therapies of Functional Dyspepsia: Self-Administrated Transcutaneous Electroacupuncture Improves Dyspeptic Symptoms

Functional dyspepsia is of high prevalence with little treatment options. The aim of this study was to develop a new treatment method using self-management transcutaneous electroacupuncture (TEA) for functional dyspepsia (FD). Twenty-eight patients with FD were enrolled and underwent a crossover clinical trial with 2-week TEA at ST36 and PC6 and 2-week sham-TEA at nonacupuncture sham-points. Questionnaires were used to assess symptoms of dyspepsia and quality of life. Physiological testing included gastric emptying and electrogastrography. It was found that (1) TEA but not sham-TEA significantly improved dyspeptic symptoms and 4 domains in quality of life; improvement was also noted in self-rated anxiety and depression scores; (2) gastric emptying was significantly and substantially increased with 2-week TEA but not sham-TEA; and (3) gastric accommodation was also improved with TEA but not sham-TEA, reflected as increased ingested nutrient volumes at the levels of satiety and maximum tolerance. These findings suggest a therapeutic potential of self-administrated TEA method for functional dyspepsia, possibly attributed to improvement in gastric motility

A comprehensive census of microbial diversity in hot springs of Tengchong, Yunnan Province China using 16S rRNA gene pyrosequencing

The Rehai and Ruidian geothermal fields, located in Tengchong County, Yunnan Province, China, host a variety of geochemically distinct hot springs. In this study, we report a comprehensive, cultivation-independent census of microbial communities in 37 samples collected from these geothermal fields, encompassing sites ranging in temperature from 55.1 to 93.6°C, in pH from 2.5 to 9.4, and in mineralogy from silicates in Rehai to carbonates in Ruidian. Richness was low in all samples, with 21–123 species-level OTUs detected. The bacterial phylum Aquificae or archaeal phylum Crenarchaeota were dominant in Rehai samples, yet the dominant taxa within those phyla depended on temperature, pH, and geochemistry. Rehai springs with low pH (2.5–2.6), high temperature (85.1–89.1°C), and high sulfur contents favored the crenarchaeal order Sulfolobales, whereas those with low pH (2.6–4.8) and cooler temperature (55.1–64.5°C) favored the Aquificae genus Hydrogenobaculum. Rehai springs with neutral-alkaline pH (7.2–9.4) and high temperature (>80°C) with high concentrations of silica and salt ions (Na, K, and Cl) favored the Aquificae genus Hydrogenobacter and crenarchaeal orders Desulfurococcales and Thermoproteales. Desulfurococcales and Thermoproteales became predominant in springs with pH much higher than the optimum and even the maximum pH known for these orders. Ruidian water samples harbored a single Aquificae genus Hydrogenobacter, whereas microbial communities in Ruidian sediment samples were more diverse at the phylum level and distinctly different from those in Rehai and Ruidian water samples, with a higher abundance of uncultivated lineages, close relatives of the ammonia-oxidizing archaeon “Candidatus Nitrosocaldus yellowstonii”, and candidate division O1aA90 and OP1. These differences between Ruidian sediments and Rehai samples were likely caused by temperature, pH, and sediment mineralogy. The results of this study significantly expand the current understanding of the microbiology in Tengchong hot springs and provide a basis for comparison with other geothermal systems around the world

Regulation of PIN-FORMED Protein Degradation

Auxin action largely depends on the establishment of auxin concentration gradient within plant organs, where PIN-formed (PIN) auxin transporter-mediated directional auxin movement plays an important role. Accumulating studies have revealed the need of polar plasma membrane (PM) localization of PIN proteins as well as regulation of PIN polarity in response to developmental cues and environmental stimuli, amongst which a typical example is regulation of PIN phosphorylation by AGCVIII protein kinases and type A regulatory subunits of PP2A phosphatases. Recent findings, however, highlight the importance of PIN degradation in reestablishing auxin gradient. Although the underlying mechanism is poorly understood, these findings provide a novel aspect to broaden the current knowledge on regulation of polar auxin transport. In this review, we summarize the current understanding on controlling PIN degradation by endosome-mediated vacuolar targeting, autophagy, ubiquitin modification and the related E3 ubiquitin ligases, cytoskeletons, plant hormones, environmental stimuli, and other regulators, and discuss the possible mechanisms according to recent studies

Weanling Offspring of Dams Maintained on Serine-Deficient Diet Are Vulnerable to Oxidative Stress

Serine plays an important role in the antioxidant defense system. However, the effects of maternal serine deficiency on the antioxidant ability of weanling offspring have not been reported. In the present study, we investigated the oxidative status of offspring of dams that are maintained on serine-deficient diet and subjected to diquat challenge. Individual pregnant animals were randomly divided into two dietary groups, namely, the control diet group and the serine- and glycine-deficient diet group. Samples were collected from weanling offspring at the age of 3 weeks after diquat challenge. Our results showed that maternal serine deficiency did not affect the levels of antioxidant enzymes and reactive oxygen species, as well as the expression of cellular and mitochondrial stress markers (Hspd1 and Hspa1a), which indicated that maternal serine deficiency did not affect basal oxidative status in weanling offspring. However, the weanling offspring were found to be vulnerable to oxidative challenges. Furthermore, our results suggested that the dysfunctional antioxidant system in response to oxidative stress in offspring of dams fed with serine-deficient diet was primarily caused by reduced availability of nicotinamide adenine dinucleotide phosphate. Furthermore, impairment of the antioxidant defense system caused by maternal serine deficiency was mediated by the Akt/AMPK/Sirt1 pathway. Our results indicated that maternal serine availability is important for maintaining antioxidant defense against oxidative challenge in weanling offspring

Analysis of Regional Tourism Strategy Cooperation Based on the Evolutionary Game Theory

This paper uses evolutionary game theory to analyse regional tourism cooperation. Asymmetricevolutionary game model is established to explore the intrinsic motivation of regional tourismcooperation, and we via rigorous mathematical reasoning to prove a series of proposition. At the same time, through numerical simulation on each proposition by the MATLAB software, it vividly reflects the evolution process of the regional tourism cooperation. The results show that, first, it is necessary to cooperate, which is the inevitable trend in the development; Second, we shall specify the necessary condition to maintain cooperation, when the no-cooperative party can obtain additional benefit of freeriding from the cooperation party, and the additional benefit is greater than the benefit from bilateral cooperation, cooperation will ultimately fail; third, we must focus on the sufficient conditions to guarantee cooperation, which mainly reflected on the utilization of shared resources, cooperation cost, the benefit of “free-riding” etc.. In view of the results, we propose some suggestions to promote regional tourism cooperation from the regulations of regional tourism cooperation, government and the utilization of shared resources

Tourism Attraction and Tourist Satisfaction with World Heritage: A Case Study of Mount Wuyi

This paper takes Mount Wuyi - a world natural and cultural heritage site - as an example. It collects data through questionnaires, employs factor analysis to explore tourism attraction of world heritage and adopts the ologit model for regression analysis of tourist satisfaction. The results show: firstly, world heritage brand significantly enhances the attractiveness of tourist attractions. Secondly, natural landscape, tea culture, ecological environment, accommodation, transportation, ticket price, staff service quality and world heritage brand all significantly and positively influence tourists’ overall satisfaction while cultural relics, security conditions and individual characteristics have no significant impact. Finally, this paper puts forward some suggestions about the construction and management for Mount Wuyi

Optimized Tibial Nerve Stimulation Partially Reduces Visceral Hypersensitivity in Rats Mediated via Autonomic and Opioid Mechanisms

ObjectivesThe aim of this study was to investigate the therapeutic effect and possible mechanisms of tibial nerve stimulation (TNS) on visceral hypersensitivity in rats.Materials and Methods1) The effects of TNS with five sets of parameters on visceral sensitivity in normal rats were evaluated by the assessment of abdominal electromyogram (EMG) and abdominal withdrawal reflex (AWR). 2) The effects and mechanisms of TNS with a special set of parameters (14 Hz, 330 μsec, and 40% motor threshold) were evaluated in acute visceral hypersensitivity rats induced by restraint stress and colonic hypersensitized rats induced by acetic acid during the neonatal stage assessed by the EMG, AWR, and the spectral analysis of heart rate variability derived from the electrocardiogram.Results1) In normal rats, TNS did not show any effect on the visceromotor reflex. 2) In rats with restraint stress‐induced hypersensitivity, TNS with the special set of parameters reduced AWR scores and EMG responses to rectal distention at a pressure of 20–60 mmHg (p < 0.05, vs. baseline for both AWR and EMG). Concurrently, TNS increased vagal activity and decreased sympathetic activity (p < 0.03 for both). 3) Similar effects were noted on the EMG (p < 0.05, vs. baseline) and AWR (p < 0.05 vs. baseline) with acute and chronic TNS in rats with chronic colonic hypersensitivity and the effects were blocked by naloxone.ConclusionsTNS with parameters of 14 Hz, 330 μsec, and 40% motor threshold is effective in improving visceral hypersensitivity in rodent models of colonic hypersensitivity via the modulation of autonomic and opioid mechanisms.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/169304/1/ner13378.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/169304/2/ner13378_am.pd