Terrestrial Compound Protein Replacing Dietary Fishmeal Improved Digestive Enzyme Activity, Immune Response, Intestinal Microflora Composition, and Protein Metabolism of Golden Pompano (Trachinotus ovatus).

Terrestrial compound protein (Cpro) can be potentially used to replace fishmeal (FM) in the marine carnivorous teleost, golden pompano (Trachinotus ovatus). Four isonitrogenous (45%) and isolipidic (12%) diets named FM30, AP80, PP80, and CP80 were formulated. FM30 (control) contained 30% FM and 25% basic protein, while AP80, PP80, and CP80 only contained 6% FM, where 80% FM and 25% basic protein of control diet were completely replaced by animal protein, plant protein, and Cpro, respectively. After golden pompano juveniles (initial weight: 10.32 ± 0.09 g) were, respectively, fed the four diets in floating sea cages for 10 weeks, the growth performance, intestinal digestive enzyme activity, and immune responses, protein metabolism indices of the CP80 group were similar to or better than those of the FM30 group (P > 0.05), and significantly better than those of the AP80 and PP80 groups. Specifically, the weight gain (WG), feed conversion ratio (FCR), activity of alanine transaminase (ALT), growth hormone (GH), and insulin-like growth factor-1 (IGF-1) contents of serum, mRNA level of interleukin-10 (il-10), zonula occludens-2 (zo-2), claudin-3, claudin-12, and eukaryotic translation initiation factor 4G (eif4g) were significantly higher, and the activity of α-amylase (AMS), lipase (LPS) in the foregut and midgut, interleukin-8 (il-8) expression in the intestine was significantly lower than that in the CP80 group, compared with those in AP80 and PP80 groups (P < 0.05). Moreover, the intestinal microflora composition of golden pompano fed with the CP80 diet was improved. Specifically, at the phylum level, the relative abundance of harmful bacterial strains cyanobacteria and TM7 of CP80 group was similar to those of FM30 group (P > 0.05), but was significantly lower than those of AP80 and PP80 groups (P < 0.05). At the genus level, the beneficial bacterial strains Agrobacterium and Blantia of CP80 group were also similar to those of FM30 group (P < 0.05), which were significantly higher than those of AP80 and PP80 groups, but the beneficial bacterial strains Bifidobacterium and Devosia of CP80 group were significantly higher than that in the other groups (P < 0.05). Besides, in diet CP80, the contents of amino acids and anti-nutritional factor, as well as the in vitro digestion rate were comparable to those of FM30, and the anti-nutritional factor content was between AP80 and PP80; total essential amino acids (EAAs) and methionine contents were higher than those in AP80, the glycine content was higher than that in PP80. Taken together, these results indicated that the CP80 diet had better amino acid composition and relatively low content of anti-nutritional factors, as well as high-digestion rate, and thus leads to the fish fed CP80 displaying improved effects in digestive enzyme activity, immune response, protein metabolism, and intestinal microbiota composition, which may be the important reasons to explain why that 80% of FM can be replaced by Cpro in the diet of golden pompano.

Effects of dietary n-3 highly unsaturated fatty acids on growth, non-specific immunity, expression of some immune-related genes and resistance to Vibrio harveyi in hybrid grouper (♀ Epinephelus fuscoguttatus × â™‚ Epinephelus lanceolatu).

This study was conducted to investigate the effects of dietary n-3 highly unsaturated fatty acids (n-3 HUFA) on growth performance, non-specific immunity, expression of some immune-related genes and resistance to Vibrio harveyi in juvenile hybrid grouper (♀ Epinephelus fuscoguttatus × â™‚ Epinephelus lanceolatu). Six isoproteic and isolipidic experimental diets were formulated with graded levels of n-3 HUFA (0.65, 1.00, 1.35, 1.70, 2.05 and 2.40% of dry matter, respectively), and the 0.65% group was used as control group. Each diet was randomly allocated to triplicate groups of fish in 1000 L fiberglass tank, and each tank was stocked with 40 fish (initial weight 12.06 ± 0.01 g) for 8 weeks. Results showed that feed conversion ratio (FCR), survival rate (SR), hepatosomatic index (HSI) and condition factor (CF) were all not significantly affected by dietary n-3 HUFA levels (P > 0.05). Weight gain (WG) and specific growth rate (SGR) in 1.35% group were significantly higher than those in 2.40% group (P < 0.05). Crude lipid of body in 1.00% group was significantly lower than that in 1.70% and 2.40% groups (P < 0.05). Liver and muscle fatty acid profiles reflected that of diets. Before challenge with Vibrio harveyi, the activity of serum superoxide dismutase (SOD), catalase (CAT) and content of complement 3 (C3) in 1.35% and 1.70% groups significantly higher than those of control group (P < 0.05). After challenge with Vibrio harveyi, serum CAT, glutathione peroxidase (GSH-PX), lysozyme (LZM) and C3 all increased sharply, while SOD showed the opposite trend. Before challenge with Vibrio harveyi, the expression levels of intestine toll-like receptor 22 (TLR22) and myeloid differentiation factor 88 (MyD88) mRNA in 2.40% group were significantly increased, and the expression levels of tumour necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) mRNA in 2.05% group were significantly higher than those in 1.00% and 1.35% groups (P < 0.05). In addition, the TLR22 and IL-1ß mRNA levels in kidney of 1.70% group were significantly lower than those in control group (P < 0.05). After challenge with Vibrio harveyi, the expression level of MyD88 mRNA in intestine of 1.35% group was significantly higher than that in 1.00% group and from 1.70% to 2.40% groups (P < 0.05), while TNF-α and IL-1ß obtained minimum values in 1.70% group. In the kidney, the interleukin 10 (IL10) mRNA expression was significantly higher in 1.70% group than that in other groups, while the IL-1ß expression in 1.70% group was on the contrary and significantly lower than that in 2.40% group (P < 0.05). Results of this study suggested that moderate dietary n-3 HUFA (1.47%-1.70% HUFA) could improve the growth performance, non-specific immunity and inhibit the inflammatory response of hybrid grouper.

Neural stem cell secretome and its role in the treatment of neurodegenerative disorders.

Neurological diseases in the central nervous system are mostly characterized by the failure of endogenous repair to restore tissue damage and salvage lost function. Currently, studies have shown that neural stem cell transplantation provides a good therapeutic effect on neurological diseases. For this reason, neural stem cell transplantation has been explored as a cell replacement therapy. Although transplanted cells can replace cells lost during or post central nervous system injury, many studies have shown that this mechanism is insufficient as most of these newly formed cells fail to integrate and eventually die. Although it was initially thought that neural stem cell could only replace lost cells, recent experiments have shown that transplanted neural stem cell can also play bystander roles such as neuroprotection and immune regulation, promote tissue repair by preventing tissue damage, interfere with pathogenic processes, or by rescuing endogenous nerve cells. However, compelling evidence has raised concerns about this bystander effect, which can be caused by several biologically active molecules (collectively known as the secretome) produced by neural stem cells. These results also raise the possibility of the neural stem cell secretome as a potential candidate for neural stem cell transplantation therapies based on the bystander effect. A better understanding of the molecules and mechanisms of this effect is of critical importance for neural stem cell-based therapies. This review aims to discuss the function and application of neural stem cell secretome in the treatment of neurodegenerative disorders.

Dietary Fishmeal Can Be Partially Replaced with Non-Grain Compound Proteins through Evaluating the Growth, Biochemical Indexes, and Muscle Quality in Marine Teleost Trachinotus ovatus.

In the context of human food shortages, the incorporation of non-grain feedstuff in fish feed deserves more research attention. Here, the feasibility and appropriate ratio of non-grain compound protein (NGCP, containing bovine bone meal, dephenolized cottonseed protein, and blood cell meal) for dietary fishmeal (FM) replacement were explored in golden pompano (Trachinotus ovatus). Four isonitrogenous (45%) and isolipidic (12%) diets (Control, 25NGP, 50NGP, and 75NGP) were prepared. Control contained 24% FM, whereas the FM content of 25NGP, 50NGP, and 75NGP was 18%, 12%, and 6%, respectively, representing a 25%, 50%, and 75% replacement of FM in Control by NGCP. Juvenile golden pompano (initial weight: 9.71 ± 0.04 g) were fed the four diets for 65 days in sea cages. There was no significant difference between the 25NGP and Control groups in terms of weight gain, weight gain rate, and specific growth rate; contents of crude protein, crude lipid, moisture, and ash in muscle and whole fish; muscle textural properties including hardness, chewiness, gumminess, tenderness, springiness, and cohesiveness; and serum biochemical indexes including total protein, albumin, blood urea nitrogen, HDL cholesterol, total cholesterol, and triglycerides. However, the golden pompano in 50NGP and 75NGP experienced nutritional stress, and thus some indicators were negatively affected. In addition, compared to the Control group, the expression levels of genes related to protein metabolism (mtor, s6k1, and 4e-bp1) and lipid metabolism (pparγ, fas, srebp1, and acc1) of the 25NGP group showed no significant difference, but the 4e-bp1 and pparγ of the 75NGP group were significantly upregulated and downregulated, respectively (p < 0.05), which may explain the decline in fish growth performance and muscle quality after 75% FM was replaced by NGCP. The results suggest that at least 25% FM of Control can be replaced by NGCP, achieving a dietary FM content of as low as 18%; however, the replacement of more than 50% of the dietary FM negatively affects the growth and muscle quality of golden pompano.

A Preclinical Model to Assess Brain Recovery After Acute Stroke in Rats.

The purpose of this study was to establish and validate an animal brain ischemia model in the recovery and sequela stages. A middle cerebral artery occlusion/reperfusion (MCAO/R) model in male Sprague-Dawley rats was chosen. By changing the rat's weight (260-330 g), the thread bolt type (2636/2838/3040/3043) and the brain infarct time (2-3 h), a higher Longa's score, a larger infarct volume and a greater model success ratio were screened using the Longa's score and TTC staining. The optimum model condition (300 g, 3040 thread bolt, 3 h brain infarct time) was acquired and used in a 1-90 day observation period after reperfusion via assessment of sensorimotor functions and infarct volume. At these conditions, the bilateral asymmetry test had a significant difference from 1 to 90 days, and the grid-walking test had a significant difference from 1 to 60 days; both differences could be a suitable sensorimotor functional test. Thus, the most appropriate condition of a novel rat model in the recovery and sequela stages of brain ischemia was found: 300 g rats that underwent MCAO with a 3040 thread bolt for a 3 h brain infarct and then reperfused. The appropriate sensorimotor functional tests were a bilateral asymmetry test and a grid-walking test.