Effects of dietary tributyrin and physterol ester supplementation on growth performance, intestinal morphology, microbiota and metabolites in weaned piglets.

AIM: This study was conducted to investigate the effects of dietary tributyrin (TB) and physterol ester (PSE) supplementation on the growth performance and intestinal health of weaned piglets. METHODS AND RESULTS: Ninety-six piglets were randomly allocated to one of four groups, including a control group (basal diet), TB group (basal diet + 1500 g t-1  TB), PSE group (basal diet + 300 g t-1 PSE) and TB + PSE group (basal diet + 1500 g t-1  TB + 300 g t-1 PSE). All groups had eight replicates with three piglets per replicate. The experiment lasted for 28 days. The results showed that dietary TB supplementation increased (p < 0.05) average daily feed intake and average daily gain, as well as the acetate and butyrate concentration in ileum, and dietary PSE supplementation decreased (p < 0.05) the ratio of feed to gain (F/G) on days 1-14 of the trial. Dietary TB or PSE alone supplementation improved the ratio of villus height to crypt depth (VH/CD) and the expression level of Occludin in ileum. The linear discriminant analysis effect size analysis identified eight biomarkers in the control group, 18 in the TB + PSE group, two in the PSE group in ileum respectively. Correlation analysis showed that the relative abundances of Enterococcus, and Streptococcus were positively correlated (p < 0.05) with propionate concentration, while the relative abundance of Clostridium_sensu_stricto_1 was negatively correlated (p < 0.05) with acetate concentration in ileum. CONCLUSION: These findings suggest that dietary TB or PSE alone supplementation could alter the growth performance, intestinal morphology, microbiota community and metabolites of weaned piglets. SIGNIFICANCE AND IMPACT OF THE STUDY: Weaning stress is a major cause of slow growth and increased diarrhoea in piglets. This study demonstrated that dietary TB and PSE presented a beneficial role in growth performance and gut health via regulating intestinal morphology, microbiota composition and metabolites.

Light-excited photoelectrons coupled with bio-photocatalysis enhanced the degradation efficiency of oxytetracycline.

Intimately coupled photocatalysis and biodegradation (ICPB) is a novel wastewater treatment technique that has potential applications in refractory degradation. This paper reports a synergistic degradation protocol that allowing the transfer of photoelectrons between photocatalysts and microbes without supplementary electron donors or improving the loading rate of the photocatalysts. As a result, a degradation rate of ∼94% was sustained for 400 h in a perturbation setup with a hydraulic retention time of 4.0 h. We achieved the degradation of ß-apo-oxytetracycline, a stable antimicrobial intermediate compound (half-life of 270 d in soil interstitial water), within 10 min, and no accumulation was observed. Moreover, the required loading rate of the photocatalyst was dramatically reduced to 18.3% compared to previous reports which mentioned much higher rates. The results of our study provided a new strategy to improve the degradation efficiency of oxytetracycline and give new insight into the degradation mechanism of the bio-photocatalytic degradation system.

Effects of dietary supplementation with glutamate and aspartate on diquat-induced oxidative stress in piglets.

This study aimed to investigate the protective effects of dietary glutamate and aspartate supplementations on diquat-induced oxidative stress in piglets. Diquat injection significantly reduced growth performance, including body weight, average daily weight gain, and feed intake (P<0.05). Meanwhile, diquat administration induced oxidative stress evidenced by the decreased serum nitric oxide (NO) and elevated malondialdeyhde (MDA) concentration (P<0.05). Furthermore, diquat-induced oxidative stress disrupted intestinal absorption system and decreased serum threonine, serine, and glycine levels. Dietary supplementation with glutamate improved final body weight, antioxidant system, and expressions of amino acids transporters and enhanced serum glutamate concentration compared with diquat group (P<0.05). While aspartate failed to alleviate diquat-induced oxidative stress, growth depression, and dysfunction of nutrients absorption except for liver relative weight. In conclusion, dietary supplementation with glutamate confers beneficial effects on diquat-induced oxidative stress in piglets, while aspartate exhibits little effects.

Peptide-based cancer therapy: opportunity and challenge.

Cancer is one of the leading causes of death worldwide. Conventional cancer therapies mainly focus on mass cell killing without high specificity and often cause severe side effects and toxicities. Peptides are a novel class of anticancer agents that could specifically target cancer cells with lower toxicity to normal tissues, which will offer new opportunities for cancer prevention and treatment. Anticancer peptides face several therapeutic challenges. In this review, we present the sources and mechanisms of anticancer peptides and further discuss modification strategies to improve the anticancer effects of bioactive peptides.

Rupintrivir is a promising candidate for treating severe cases of enterovirus-71 infection: evaluation of antiviral efficacy in a murine infection model.

Enterovirus-71 (EV71) infections can cause life-threatening diseases with neurological symptoms. Currently, no direct targeting antivirals are available to combat severe EV71 infection. Rupintrivir (AG7088) is a compound originally designed for Rhinovirus 3C protease. Previous computational analyses by us and crystallography studies by others suggested that rupintrivir is also a high affinity inhibitor to EV71 3C. Thus, we aimed to further evaluate its anti-EV71 activity in vivo at clinically acceptable doses. It was observed that administration of rupintrivir in suckling mice largely protected them from limb paralysis and dramatically improved survival (38.5% DMSO vs. 90.9% at 0.1mg/kg, p=0.006). Histological, immunohistochemical and quantitative RT-PCR analyses confirmed that rupintrivir profoundly alleviated virus induced necrotizing myositis, suppressed viral RNA and blocked EV71 VP1 expression in various tissues. In conclusion, we established that rupintrivir can strongly contain the spread of EV71 infection in vivo at a clinically acceptable dose (as low as 0.1mg/kg). As its safety has been fully tested in previous clinical trials, rupintrivir is suitable for immediate evaluation of potential benefits in EV71-infected individuals with life-threatening neurological symptoms.

Gene expression is altered in piglet small intestine by weaning and dietary glutamine supplementation.

Dietary supplementation of glutamine prevents intestinal dysfunction and atrophy in weanling piglets, but the underlying mechanism(s) are largely unknown. This study was conducted to test the hypothesis that weaning or glutamine may modulate expression of genes that are crucial for intestinal metabolism and function. In Expt. 1, we obtained small intestine from 28-d-old pigs weaned at 21 d of age and from age-matched suckling piglets. In Expt. 2, piglets were weaned at 21 d of age and then had free access to diets supplemented with 1% L-glutamine (wt:wt) or isonitrogenous L-alanine (control). At d 28, we collected small intestine for biochemical and morphological measurements and microarray analysis of gene expression using the Operon Porcine Genome Oligo set. Early weaning resulted in increased (52-346%) expression of genes related to oxidative stress and immune activation but decreased (35-77%) expression of genes related to macronutrient metabolism and cell proliferation in the gut. Dietary glutamine supplementation increased intestinal expression (120-124%) of genes that are necessary for cell growth and removal of oxidants, while reducing (34-75%) expression of genes that promote oxidative stress and immune activation. Functionally, the glutamine treatment enhanced intestinal oxidative-defense capacity (indicated by a 29% increase in glutathione concentration), prevented jejunal atrophy, and promoted small intestine growth (+12%) and body weight gain (+19%) in weaned piglets. These findings reveal coordinate alterations of gene expression in response to weaning and aid in providing molecular mechanisms for the beneficial effect of dietary glutamine supplementation to improve nutrition status in young mammals.