Liver transcriptome and physiological analyses preliminarily revealed the adaptation mechanisms of Amur grayling (Thymallus arcticus grubei, Dybowski, 1869) fry for dietary lipid nutrition

The Amur grayling (Thymallus arcticus grubei Dybowski, 1869), a species of potentially economic and research value, is renowned for its tender meat, exquisite flavor, and high nutritional contents. This study was conducted to investigate the physiological adaptation mechanisms to dietary lipids in Amur grayling fry (with average initial weight 4.64±0.03 g). This study involved a 56-day feeding trial with diets containing varying lipid levels (9.07%, 12.17%, 15.26%, 18.09%, 21.16%, and 24.07%, designated as GL1 through GL6, respectively) to explore the impact of dietary lipids on growth performance, intestinal digestion, liver antioxidative function, and transcriptomic profiles. Results showed that The group receiving 18% dietary lipid exhibited a markedly higher weight gain rate (WGR) and specific growth rate compared to other groups, alongside a reduced feed conversion ratio (FCR), except in comparison to the 15% lipid group. Activities of lipase in pancreatic secretion and amylase in stomach mucosa peaked in the 18% lipid treatment group, indicating enhanced digestive efficiency. The liver of fish in this group also showed increased activities of antioxidative enzymes and higher levels of glutathione and total antioxidative capacity, along with reduced malondialdehyde content compared to the 9% and 24% lipid treatments. Additionally, serum high-density lipoprotein cholesterol levels were highest in the 18% group. Transcriptomic analysis revealed four significant metabolic pathways affected: Cholesterol metabolism, Fat digestion and absorption, PPAR signaling, and Fatty acid degradation, involving key genes such as Lipase, Lipoprotein lipase, Fatty acid-binding protein, and Carnitine palmitoyltransferase I. These findings suggest that the liver of Amur grayling employs adaptive mechanisms to manage excessive dietary lipids. Quadratic regression analysis determined the optimal dietary lipid levels to be 16.62% and 16.52%, based on WGR and FCR, respectively. The optimal dietary lipid level for juvenile Amur grayling appears to be around 18%, as evidenced by improved growth performance, digestive function, balanced serum lipid profile, and enhanced liver antioxidative capacity. Exceeding this lipid threshold triggers both adaptive and potentially detrimental liver responses.

Suitable Cottonseed Protein Concentrate Supplementation in Common Carp (Cyprinus carpio) Serves as an Effective Strategy for Fish Meal Sparing Based on Improvement in Intestinal Antioxidant Capacity, Barrier and Microbiota Composition

The application of cottonseed protein concentrate (CPC) is an effective strategy to moderate the shortage of fish meal (FM) for the aquafeed industry. However, little attention has been paid to the effects of replacing fishmeal with CPC on cyprinid fish. This study used common carp (Cyprinus carpio) as the biological model and assessed the potential of applying CPC as a substitute for fishmeal in the diet of common carp. The proportion of fish meal substituted with CPC in the six diets was 0% (CPC0), 25% (CPC25), 50% (CPC50), 75% (CPC75), and 100% (CPC100). Each diet was fed to three replicate groups of common carp (4.17 ± 0.02 g) for 56 days. Results revealed that the CPC50 group significantly increased the growth indexes via up-regulating the genes of the GH/IGF axis and the TOR pathway. The intestinal digestive ability was also elevated in the CPC50 group via markedly increasing intestinal villus height, protease and lipase activities in the whole intestine, and the amylase activity of the foregut and midgut. The CPC50 group captured significantly higher activities and gene expressions of antioxidant enzymes and lower malonaldehyde contents via evoking the Nrf2/Keap1 signal pathway. The CPC50 group enhance the intestinal mechanical barrier via up-regulating the gene expressions of tight junction proteins and heighten the intestinal biological barrier by increasing the probiotics (Lactococcus) and decreasing the harmful bacteria (Enterococcus). But excessive substitution levels (75% and 100%) would compromise growth performance, intestinal antioxidant capacity, and immune function. The optimum substitution level was estimated to be 46.47%, 47.72%, and 46.43% using broken-line regression analyses based on mass gain rate, protein efficiency ratio, and feed conversion rate. Overall, the fishmeal in common carp feed could be substituted up to 50% by CPC without negative influence on growth, feed utilization, and or intestinal health.

Seedlings of Poncirus trifoliata exhibit tissue-specific detoxification in response to NH4 + toxicity

Ammonium nitrogen (NH4 +-N) is essential for fruit tree growth, but the impact of excess NH4 +-N from fertilizer on evergreen citrus trees is unclear. In a climate chamber, 8-month-old citrus plants were exposed to five different hydroponic NH4 +-N concentrations (0, 5, 10, 15 and 20 mm) for 1 month to study effects of NH4 +-N on growth characteristics, N uptake, metabolism, antioxidant enzymes and osmotic regulatory substances. Application of 10 mm NH4 +-N adversely affected root plasma membrane integrity, root physiological functions, and plant biomass. MDA, CAT, POD, APX and SOD content were significantly correlated with leaf N metabolic enzyme activity (GOGAT, GDH, GS and NR). GDH was the primary enzyme involved in NH4 +-N assimilation in leaves, while the primary pathway involved in roots was GS-GOGAT. Under comparatively high NH4 + addition, roots were the main organs involved in NH4 + utilization in citrus seedlings. Our results demonstrated that variations in NH4 + concentration and enzyme activity in various organs are associated with more effective N metabolism in roots than in leaves to prevent NH4 + toxicity in evergreen woody citrus plants. These results provide insight into the N forms used by citrus plants that are important for N fertilizer management.

Comprehensive assessment of detoxification mechanisms of hydrolysis fish peptides in largemouth bass (Micropterus salmoides) under copper exposure: Tracing from bioaccumulation, oxidative stress, lipid deposition to metabolomics

As a heavy metal, copper is toxic to aquatic organisms in water, causing oxidative stress and lipid deposition. However, there is currently no effective dietary strategy to prevent damage caused by copper exposure. Here, copper bioaccumulation, antioxidant enzymes, lipogenic enzymes, lipid metabolism-related gene expression levels and metabolic pathways were synthesized and evaluated in copper-exposed largemouth bass (Micropterus salmoides) after hydrolysis fish peptides (HFP) pretreatment. The results showed that supplementation with 1% (P < 0.05), 3% (P < 0.01) and 5% (P < 0.05) HFP significantly reduced the copper bioaccumulation in largemouth bass. Hydrolysis fish peptides supplementation significantly reduced the activities of total antioxidant capacity (P < 0.01) and catalase (P < 0.01) and the contents of glutathione (P < 0.01) and malondialdehyde (P < 0.05). Fatty acid synthetase concentration was significantly reduced in fish supplemented with 3% (P < 0.05) and 5% HFP (P < 0.05). Similarly, fish fed 3% (P < 0.05) and 5% (P < 0.01) HFP significantly reduced the glucose-6-phosphate dehydrogenase concentration. Serum metabolomics revealed that 85, 144 and 207 differential metabolites were obtained in fish supplemented with 1%, 3% and 5% HFP, respectively. The differential metabolites were mainly lipids and lipid-like molecules, which were associated with the lipid metabolism pathways. The expression levels of fatty acid synthase (P < 0.01), sterol regulatory element binding protein-1c (P < 0.05), liver X receptor (P < 0.001), peroxisome proliferator activated γ (P < 0.01), apolipoprotein B (P < 0.001) and fatty acid-binding protein 1 (P < 0.01) were significantly down-regulated and the expression levels of carnitine palmitoyltransferase 1α (P < 0.01), hormone-sensitive lipase (P < 0.001), apolipoprotein A 1 (P < 0.05) were significantly up-regulated in fish fed with 3% HFP. Additionally, supplementation with 3% (P < 0.01) and 5% (P < 0.001) HFP significantly up-regulated the expression level of B-cell lymphoma-2 with a dose-dependent effect. In conclusion, our study confirmed that HFP supplementation was closely associated with oxidative stress, enzymatic activities and related pathways of lipid metabolism, and apoptosis, and in general alleviated lipid deposition caused by copper exposure in largemouth bass.

Fibulin-1 Regulates Initiation of Successional Dental Lamina

In humans, teeth are replaced only once, and the successional dental lamina (SDL) of the permanent tooth is maintained in a quiescent state until adolescence. Recently, we showed that biomechanical stress generated by the rapid growth of the deciduous tooth inhibits SDL development via integrin β1-RUNX2 signaling at embryonic day 60 (E60) in miniature pigs. However, the mechanism by which RUNX2 regulates SDL initiation within the SDL stem cell niche remains unclear. In the current study, we transcriptionally profiled single cells from SDL and surrounding mesenchyme at E60 and identified the landscape of cellular heterogeneity. We then identified a specific fibroblast subtype in the dental follicle mesenchyme between the deciduous tooth and the SDL of the permanent tooth (DFDP), which constitutes the inner part of the niche (deciduous tooth side). Compared with traditional dental follicle cells, the specific expression profile of DFDP was identified and found to be related to biomechanical stress. Subsequently, we found that RUNX2 could bind to the enhancer regions of Fbln1 (gene of fibulin-1), one of the marker genes for DFDP. Through gain- and loss-of-function experiments, we proved that the biomechanical stress-mediated RUNX2-fibulin-1 axis inhibits the initiation of SDL by maintaining SDL niche homeostasis.

Contouring Analysis on Synthetic Contrast-Enhanced MR from GRMM-GAN and Implications on MR-Guide Radiation Therapy

PURPOSE/OBJECTIVE(S)

MR-guided linear accelerators have been commercialized making MR-only planning and adaptation an appealing alternative circumventing MR-CT registration. However, obtaining daily contrast-enhanced MR images can be prohibitive due to the increased risk of side effects from repeated contrast injections. In this work, we evaluate the quality of contrast-enhanced multi-modal MR image synthesis network GRMM-GAN (gradient regularized multi-modal multi-discrimination sparse-attention fusion generative adversarial network) for MR-guided radiation therapy.

MATERIALS/METHODS

With IRB approval, we trained the GRMM-GAN based on 165 abdominal MR studies from 65 patients. Each study included T2, T1 pre-contrast (T1pre), and T1 contrast enhanced (T1ce) images. The two pre-contrast MR modalities, T2 and T1pre images were adopted as inputs for GRMM-GAN, and the T1ce image at the portal venous phase was used as an output. Ten MR scans containing 21 liver tumors were selected for contouring analysis. A Turing test was first given to six radiation oncologists, in which 100 real T1ce and synthetic T1ce image slices are randomly given to the radiation oncologists to determine the authenticity of the synthesis. We then invited two radiation oncologists (RadOnc 1 and RadOnc2) to manually contour the 21 liver tumors independently on the real T1ce images. RadOnc2 then performed contouring on the respective synthetic T1ce MRs. DICE coefficient (defined as the intersection over the average of two volumes) and Hausdorff distance (HD, measuring how far two volumes are from each other) were used as analysis metrics. The DICE coefficients were calculated from the two radiation oncologists' contours on the real T1ce MR for each tumor. The DICE coefficients were also calculated from RadOnc 2's contours on real and synthetic MRs. Besides, tumor center shifts were extracted. The tumor center of mass coordinates was extracted from real and synthetic volumes. The difference in the coordinates indicated the shifts in the superior-inferior (SI), right-left (RL), and anterior-posterior (AP) directions between real and synthetic tumor volumes.

RESULTS

An average of 52.3% test score was achieved from the six radiation oncologists, which is close to random guessing. RadOnc 1 and RadOnc 2, who had participated in the contouring analysis, achieved an average DICE of 0.91±0.02 from tumor volumes drawn on the real T1ce MRs. This result sets the inter-operator uncertainty baseline in the real clinical setting. RadOnc 2 achieved an average DICE (real vs. synth) of 0.90±0.04 and HD of 4.76±1.82 mm. Only sub-millimeter (SI: 0.67 mm, RL: 0.41 mm, AP: 0.39 mm) tumor center shifts were observed in all three directions.

CONCLUSION

The GRMM-GAN method has the potential for MR-guided liver radiation when contrast agents cannot be administered daily and provide synthetic contrast-enhanced MR for better tumor targeting. The network can produce synthetic MR images with satisfactory contour agreement and geometric integrity.

Genetically Encoded RNA Sensors for Ratiometric and Multiplexed Imaging of Small Molecules in Living Cells

Genetically encoded sensors afford powerful tools for studying small molecules and metabolites in live cells. However, genetically encoded sensors with a general design remain to be developed. Here we develop genetically encoded RNA sensors with a modular design for ratiometric and multiplexed imaging of small molecules in live cells. The sensor utilizes aptazyme as a recognition module and the light-up RNA aptamer as a signal reporter. The conformation of light-up aptamers is abrogated by a blocking sequence, and aptazyme-mediated cleavage restores the correct conformation, delivering activated fluorescence for small molecule imaging. We first developed a genetically encoded ratiometric sensor using Mango aptamer as a reference and SRB2 as a reporter. It is shown that the sensor allows quantitative imaging and detection of theophylline in live cells. The generality of the design is further demonstrated for imaging other small molecules by replacing the aptazymes. Its ability for multiplexed imaging of small molecules is further explored via the integration of different small-molecule responsive aptazymes and light-up RNA aptamers. This modular design could offer a versatile platform for imaging diverse molecules in living cells.

Momordica charantia saponins administration in low-protein-high-carbohydrate diet improves growth, blood biochemical, intestinal health and microflora composition of juvenile common carp (Cyprinus carpio)

An 8-week feeding trial was conducted to explore the feasibility of Momordica charantia saponins (MCS) administration to facilitate the protein-sparing action of high carbohydrate in diets for juvenile common carp (Cyprinus carpio) with initial mass of 5.41 ± 0.02 g. Based on our previous study, four diets with different the ratio of protein and carbohydrate (P/C ratio) were designed: 32%P/40%C, 30%P/43%C, 28%P/46%C, 28%P/46%C supplemented with 0.16% MCS (28%P/46%C + MCS). Each diet treatment was divided into 3 replicates. Results revealed that 30%P/43%C group increased growth performance and intestinal digestion, decreased intestinal inflammation, and optimized the intestinal microbiota compared to 32%P/40%C group, which presented the stronger protein-sparing action of high carbohydrate. But if the P/C ratio reduced to 28%P/46%C or less, the saving action would be restrained. However, compared to the 30%P/43%C and 28%P/46%C groups, 28%P/46%C + MCS group significantly elevated growth performance and activities of digestive enzymes and antioxidative enzymes, whilst the opposite trend occurred in the contents of glucose, triglyceride, total cholesterol, low density lipoprotein cholesterol, blood urea nitrogen, glutamic oxalacetic transaminase, glutamic-pyruvic transaminase and malondialdehyde. In addition, 28%P/46%C + MCS group markedly upregulated the expressions of GH/IGF axis genes, genes involved in protein synthesis, antioxidant genes and anti-inflammatory cytokine, whilst the opposite trend occurred in the expressions of pro-inflammatory cytokines. Moreover, 28%P/46%C + MCS group obtained the remarkably higher Enterococcus proportion and lower Lactococcus proportion compared to the 30%P/43%C and 28%P/46%C groups, whereas the opposite occurred in 30%P/43%C group, which indicated that there existed differences in the improvement mechanism on intestinal microflora composition between MCS and appropriate P/C ratio. Combined with the above mentioned changes in our research, we concluded that 0.16% MCS administration in a 28%P/46%C diet could facilitate the protein-sparing action of high carbohydrate in diets for common carp, which could decrease the 5% dosage of soybean meal and synchronously reduce the 4% crude protein of diets without affecting the growth and immune ability for common carp.

A study on prenucleation and heterogeneous nucleation in liquid Pb on solid Al using molecular dynamics simulations

In this paper, we investigate prenucleation and heterogeneous nucleation in the liquid Pb/solid Al system as an example of systems with large lattice misfit using molecular dynamics simulation. Solid Pb and Al have a large positive lattice misfit (f) of 18.2% along the densely packed [110] direction. This study reveals that prenucleation occurs at 600 K (an undercooling of 15 K), and a 2-dimensional (2D) ordered structure forms at the interface with a coincidence site lattice (CSL) between the first Pb and first Al layers. The CSL accommodates the major part of the f, and only a small residual lattice misfit (f_r) of 1.9% remains. The formation of the CSL transforms the original substrate into a considerably potent nucleant, where the first Pb layer becomes the new surface layer of the substrate. At an undercooling of about 22 K, nucleation proceeds by merging 2D ordered structure through structural templating: the second Pb layer is epitaxial to the CSL Pb layer, the third Pb layer largely accommodates the f_r, and the fourth Pb layer is a nearly perfect crystalline plane. Further analysis indicates that the interface with the CSL has a lower interfacial energy than with a cube-to-cube orientation relationship. For the first time, we established that the CSL was an effective mechanism to accommodate the f for systems with a large positive misfits. Heterogeneous nucleation is governed not by a single mechanism (misfit dislocations in Turnbull's model), but instead by various mechanisms depending on f. This study sheds new light on the atomistic mechanism of heterogeneous nucleation.

Mid-infrared frequency combs and staggered spectral patterns in χ(2) microresonators

The potential of frequency comb spectroscopy has aroused great interest in generating mid-infrared frequency combs in the integrated photonic setting. However, despite remarkable progress in microresonators and quantum cascade lasers, the availability of suitable mid-IR comb sources remains scarce. Here, we generate mid-IR microcombs relying on cascaded three-wave-mixing for the first time. By pumping a CdSiP₂ microresonator at 1.55 µm wavelength with a low power continuous wave laser, we generate χ⁽²⁾ frequency combs at 3.1 µm wavelength, with a span of about 30 nm. We observe ordinary combs states with a line spacing of the free spectral range of the resonator, and combs where the sideband numbers around the pump and half-harmonic alternate, forming staggered patterns of spectral lines. Our scheme for mid-IR microcomb generation is compatible with integrated telecom lasers. Therefore, it has the potential to be used as a simple and fully integrated mid-IR comb source, relying on only one single material.

Taurine Alleviates Chronic Social Defeat Stress-Induced Depression by Protecting Cortical Neurons from Dendritic Spine Loss

Abnormal amino acid metabolism in neural cells is involved in the occurrence and development of major depressive disorder. Taurine is an important amino acid required for brain development. Here, microdialysis combined with metabonomic analysis revealed that the level of taurine in the extracellular fluid of the cerebral medial prefrontal cortex (mPFC) was significantly reduced in mice with chronic social defeat stress (CSDS)-induced depression. Therefore, taurine supplementation may be usable an intervention for depression. We found that taurine supplementation effectively rescued immobility time during a tail suspension assay and improved social avoidance behaviors in CSDS mice. Moreover, taurine treatment protected CSDS mice from impairments in dendritic complexity, spine density, and the proportions of different types of spines. The expression of N-methyl D-aspartate receptor subunit 2A, an important synaptic receptor, was largely restored in the mPFC of these mice after taurine supplementation. These results demonstrated that taurine exerted an antidepressive effect by protecting cortical neurons from dendritic spine loss and synaptic protein deficits.

GABAergic neurons in the ventral lateral geniculate nucleus and intergeniculate leaflet modulate itch processing in mice

Itch and pain are two closely related sensations that receiving similar encodings at multiple levels. Accumulated evidences suggest that activation of the ventral lateral geniculate nucleus and intergeniculate leaflet (vLGN/IGL)-to-lateral and ventrolateral periaqueductal gray (l/vlPAG) projections mediates the antinociceptive effects of bright light therapy. Clinical study showed that bright light therapy may ameliorate cholestasis-induced pruritus. However, the underlying mechanism and whether this circuit participates in itch modulation remains unclear. In this study, chloroquine and histamine were utilized to induce acute itch models in mice. Neuronal activities in vLGN/IGL nucleus were evaluated with c-fos immunostaining as well as fiber photometry. Optogenetic manipulations were performed to activate or inhibit GABAergic neurons in the vLGN/IGL nucleus. Our results showed that the expressions of c-fos in vLGN/IGL were significantly increased upon both chloroquine- and histamine-induced acute itch stimuli. GABAergic neurons in vLGN/IGL were activated during histamine and chloroquine-induced scratching. Optogenetic activation of the vLGN/IGL GABAergic neurons exerts antipruritic effect, while inhibiting these neurons exerts pruritic effect. Our results provide evidence that GABAergic neurons in vLGN/IGL nucleus might play a crucial role in modulating itch, which may provide clue for application of bright light as an antipruritic treatment in clinic.

Integration of microRNA and mRNA analyses depicts the potential roles of Momordica charantia saponin administration in insulin resistance of juvenile common carp (Cyprinus carpio) fed with a high-starch diet

Background: The regulation of target gene mRNA mediated by microRNA may play an important role in glucose metabolism in fish. Previous research findings of our research group revealed that Momordica charantia saponin (MS) administration in a high-starch diet could improve insulin resistance of common carp through renovating insulin signaling pathways, whose fundamental mechanisms have remained unknown by far. To reveal this potential mechanism, we aimed to investigate the difference in miRNA and mRNA expression profiles between common carp fed with high-starch diets containing MS (HS_MS1 and HS_MS2) and common carp fed with high-starch (HS) diets. Results: Through miRNA deep-sequencing, 10 significantly differentially expressed miRNAs in HC and HS_MS1, including one upregulated and nine downregulated miRNAs, were identified, whereas 10 significantly differentially expressed miRNAs in HC and HS_MS2, including four upregulated and six downregulated miRNAs, were identified. These miRNAs may not only be involved in the regulation of insulin signaling pathways and insulin resistance in common carp but also be the markers for liver insulin resistance in MS therapy for the remission of insulin resistance. This study identified 10 potential known miRNAs, namely, ccr-miR-10b, ccr-miR-122, ccr-miR-143, ccr-miR-146a, ccr-miR-155, ccr-miR-16c, ccr-miR-200a, ccr-miR-29a, ccr-miR-34, and ccr-miR-375, as candidates participating in modulating the liver insulin resistance. According to the biopathway enrichment analysis of the 252 target genes using the KEGG classical biopathway database, the relative expression levels of gsk3bb, pik3r1, and pik3r3b were analyzed using RNA-seq. Compared to the HC group, a significant decrease in the relative expression levels of pik3r1 and pik3r3b was observed in HS_MS1 and HS_MS2 groups (p < 0.05). This study raised a presumption of the presence of ccr-miR-29a targeting pik3r1 or ccr-miR-143 targeting pik3r3 playing likely roles in Momordica charantia saponins remitting the liver insulin resistance. Conclusion: The findings will further deepen the understanding of the carbohydrate metabolism of common carp and provide an important scientific basis for the application of Momordica saponins as functional nutrients to alleviate insulin resistance of fish in fish culture.

Plant-specific features of respiratory supercomplex I + III2 from Vigna radiata

The last steps of cellular respiration-an essential metabolic process in plants-are carried out by mitochondrial oxidative phosphorylation. This process involves a chain of multi-subunit membrane protein complexes (complexes I-V) that form higher-order assemblies called supercomplexes. Although supercomplexes are the most physiologically relevant form of the oxidative phosphorylation complexes, their functions and structures remain mostly unknown. Here we present the cryogenic electron microscopy structure of the supercomplex I + III₂ from Vigna radiata (mung bean). The structure contains the full subunit complement of complex I, including a newly assigned, plant-specific subunit. It also shows differences in the mitochondrial processing peptidase domain of complex III₂ relative to a previously determined supercomplex with complex IV. The supercomplex interface, while reminiscent of that in other organisms, is plant specific, with a major interface involving complex III₂'s mitochondrial processing peptidase domain and no participation of complex I's bridge domain. The complex I structure suggests that the bridge domain sets the angle between the enzyme's two arms, limiting large-scale conformational changes. Moreover, complex I's catalytic loops and its response in active-to-deactive assays suggest that, in V. radiata, the resting complex adopts a non-canonical state and can sample deactive- or open-like conformations even in the presence of substrate. This study widens our understanding of the possible conformations and behaviour of complex I and supercomplex I + III₂. Further studies of complex I and its supercomplexes in diverse organisms are needed to determine the universal and clade-specific mechanisms of respiration.

Resveratrol ameliorates oxidative stress, inflammatory response and lipid metabolism in common carp (Cyprinus carpio) fed with high-fat diet

High-fat diet is regarded as crucial inducers of oxidative stress, inflammation, and metabolic imbalance. In order to investigate the ameliorative potential of resveratrol against the progression of liver injury towards steatohepatitis, common carp (Cyprinus carpio) were distributed into six experimental groups and were fed with a normal-fat diet, a high-fat diet, and supplemented with resveratrol (0.8, 1.6, 2.4, and 3.2 g/kg diet) for 8 weeks. The high-fat diet decreased the antioxidant capacities, as well as causing the inflammatory response and lipid deposition of common carp. Resveratrol induced a marked elevation in the final body weight, weight gain rate, condition factor and significant decrease in the feed conversion ratio. Moreover, dietary resveratrol showed a significant decrease in the alanine aminotransferase, aspartate aminotransferase, triglyceride and low-density lipoprotein levels, which was accompanied by an increase in high-density lipoprotein concentration in serum. A significant elevation in total superoxide dismutase, catalase, glutathione peroxidase and a decreased malondialdehyde content were observed, along with a substantial elevation in antioxidant activities were found. Additionally, fish fed with resveratrol had an up-regulation of hepatic catalase, copper, zinc superoxide dismutase, glutathione peroxidase 1a, and glutathione peroxidase 1b gene expression via Nrf2 signaling pathway. Expectedly, our results also demonstrated that resveratrol regulates hepatic lipid metabolism in fish by inhibiting the expression of hepatic lipogenesis genes (acetyl-CoA carboxylase 1, fatty acid synthase, and sterol regulatory element binding protein 1), fatty acid uptake-related genes of lipoprotein lipase, and β-oxidation-related genes via PPAR-γ signaling pathway. Furthermore, dietary resveratrol reduced inflammation, as evident by down-regulating the interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor-α expression levels and upregulating the interleukin-10 and transforming growth factor-β2 expression levels via NF-κB signaling pathway. As a whole, our results demonstrated that resveratrol defensed the impacts against high-fat diet on the serum biochemical, hepatic antioxidants, inflammation, and lipid metabolism.

Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high risk, early breast cancer

BACKGROUND

The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety.

PATIENTS AND METHODS

One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015.

RESULTS

With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Δ 3.4%, 95% CI -0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Δ 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Δ 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome.

CONCLUSION

With 3.5 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDFS and DDFS with no new safety signals.

Phosphorus Nutrition in Songpu Mirror Carp (Cyprinus carpio Songpu) During Chronic Carbonate Alkalinity Stress: Effects on Growth, Intestinal Immunity, Physical Barrier Function, and Intestinal Microflora

Carbonate alkalinity is a major environmental stress factor affecting aquatic feed configuration, which easily causes oxidative stress and hypoimmunity for fish. Hence, the purpose of the study is to assess the potential effect of phosphorus on growth, intestinal oxidation resistance, physical barrier function, and microflora for Songpu mirror carp (Cyprinus carpio Songpu) (initial average weight of 2.95 ± 0.21 g) reared at the high-concentration carbonate alkalinity environment. A two-factor, three-level (2 × 3) design was applied, in which diets with three different phosphorus levels (3.6, 7.0, and 10.5 g/kg dry matter) were randomly assigned to 0 and 15 mmol/L carbonate alkalinity groups with three replicate aquariums. After the 8-week trial, we found that weight gain rate (WGR), specific growth rate (SGR), protein efficiency ratio (PER), and lipase and amylase activities in the intestine significantly (p < 0.05) declined with increasing carbonate alkalinity. Carbonate alkalinity of 15 mmol/L significantly reduced glutathione peroxidase (GSHPx) activities in the intestine (p < 0.05). The relative expressions of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), glutathione peroxidase 1a (GPX1a), Clautin3, Clautin11, and tumor necrosis factor β (TNF-β) in the intestine were markedly downregulated by increasing carbonate alkalinity levels (p < 0.05), whilst the relative expressions of interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) in the intestine were markedly upregulated (p < 0.05). At the 15 mmol/L carbonate alkalinity treatment, Songpu mirror carp suffer from hypoimmunity status with failed digestion, antioxidant, inflammation, and immune response, thereby inducing impaired growth. Additionally, significant increments in the abundance of Proteobacteria and a significant decrease in the abundance of Fusobacteria and the Firmicutes/Bacteroidetes ratio were caused due to excessively high carbonate alkalinity (15 mmol/L) and excessively low dietary phosphorus supply (3.6 g/kg). Collectively, 7.0 g/kg dietary phosphorus supplementation was effective in promoting intestinal antioxidant enzyme activities and the corresponding gene expression via the Keap1-Nrf2 signaling pathway and in enhancing intestinal immunity by upregulating anti-inflammatory and downregulating pro-inflammatory genes. Appropriate dietary phosphorus supply could promote the formation of beneficial microflora in freshwater, and it has the potential ability to transfer the adverse effect of carbonate alkalinity stress to the structural composition of intestinal microflora. Hence, consideration should be given to suitable phosphorus supply for fish under the chronic carbonate alkalinity stress.

Low Protein Diets Supplemented With Alpha-Ketoglutarate Enhance the Growth Performance, Immune Response, and Intestinal Health in Common Carp (Cyprinus carpio)

To investigate the effects of alpha-ketoglutarate (AKG) supplementation in a low protein (LP) diet on the growth performance, immune response, and intestinal health of common carp (Cyprinus carpio), 600 carp were randomly divided into five dietary groups: a normal protein (NP) diet containing 32% crude protein, an LP diet formulated with 28% crude protein, and LP with AKG at 0.4%, 0.8%, and 1.2% (dry matter). After an 8-week trial period, the results demonstrated that an LP diet led to a decrease in performance, immune response, and intestinal barrier function. Compared with the LP group, the final body weight and weight gain rate in the LP+0.4% AKG group were significantly higher, the feed conversion ratio was significantly decreased with the addition of 0.4% and 0.8% AKG. The supplementation with 0.4% and 0.8% AKG markedly increased the activities of T-SOD and GSH-Px, as well as the expression levels of GPX1a and GPX1b relative to the LP group, whereas the MDA content was significantly decreased in the LP+0.4% AKG group. In addition, the expression levels of tight junctions including claudin-3, claudin-7, ZO-1, and MLCK were significantly up-regulated in the LP+0.4% AKG group, and the relative expression levels of the pro-inflammatory factors IL-1β and IL-6α were significantly lower with the addition of 0.4%, 0.8%, and 1.2% AKG. Moreover, the abundance of Proteobacteria in the LP+0.4% AKG group was lower than that in the LP group, and the abundance of Firmicutes and Fusobacteria was higher at the phylum level. The abundance of Citrobacter in the LP+0.4% AKG group was decreased compared to the LP group, while the abundance of Aeromonas was increased at the genus level. In short, the effects of AKG on the intestinal health of the common carp were systematically and comprehensively evaluated from the perspectives of intestinal physical barrier, chemical barrier, biological barrier, and immune barrier. We found that an LP diet supplemented with 0.4% AKG was beneficial to the growth performance and intestinal health of common carp.

Assessment of chicken intestinal hydrolysates as a new protein source to replace fishmeal on the growth performance, antioxidant capacity and intestinal health of common carp (Cyprinus carpio)

Promoting circular economy by transforming food residues into alternative high-value protein sources for aquaculture feed is a new way to develop alternative raw materials for fishmeal. This study systematically evaluated the effects of chicken intestinal hydrolysates (CIH) on the intestinal immune health of common carp through growth performance, antioxidant capacity, and intestinal immunity analysis in order to replace fishmeal. Five iso-nitrogenous and iso-lipidic experimental feeds were formulated to replace 0% (CIH-0), 25% (CIH-25), 50% (CIH-50), 75% (CIH-75) and 100% (CIH-100) of the fishmeal with CIH. Each experimental diet was fed to triplicate groups of 30 carp for 8 weeks. The results revealed that no significant differences in the final body weight, weight gain rate, feed coefficient radio, feed intake and protein efficiency ratio were found among the CIH-0, CIH-25, and CIH-50 groups, while the final body weight and weight gain rate in the CIH-75 and CIH-100 groups were significantly decreased and the feed coefficient radio was significantly increased. The aspartate aminotransferase of all CIH groups were significantly decrease, and the total protein, albumin did not differ among the CIH-0, CIH-25, CIH-50, and CIH-75 groups. The trypsin content was significantly increased in the CIH-75 and CIH-100 groups. No significant differences in the antioxidant index (catalase, glutathione peroxidase and malonaldehyde) were found among all CIH groups compared with the CIH-0 group. The expression levels of pro-inflammatory cytokines IL-1β and TNF-α were significantly down-regulated in the CIH-50 group and anti-inflammatory cytokines IL-10 and TGF-β2 were significantly up-regulated in the CIH-50 and CIH-75 groups. No significant differences in the expression levels of claudin-1, claudin-7 and claudin-11 were observed between the CIH-0 and CIH-50 groups, while the expression levels of ZO-1, occludin and MLCK were significantly up-regulated in the CIH-50 group compared with the CIH-0 group. The expression level of claudin-1 was down-regulated in the CIH-75 and CIH-100 groups. Hence, the study demonstrated the potential of CIH as a novel protein source for replacing fishmeal, and replacing 50% of fishmeal with CIH did not significantly influence the growth performance, immune responses, and intestinal barrier of common carp (Cyprinus carpio).

Assessment of Fish Protein Hydrolysates in Juvenile Largemouth Bass (Micropterus salmoides) Diets: Effect on Growth, Intestinal Antioxidant Status, Immunity, and Microflora

Varying dietary inclusion levels of fish protein hydrolysates (FPH) were applied in a feeding experiment with juvenile largemouth bass (Micropterus salmoides) to assess their effects on growth, intestinal antioxidant status, immunity, and microflora. FPH were added in 4 dietary levels: 0 g/kg (control group, FPH-0), 10 g/kg (FPH-10), 30 g/kg (FPH-30), and 50 g/kg (FPH-50) dry matter, respectively substituting 0, 5.3, 16.3, and 27.3% of fish meal with dietary fish meal. Quadruplicate groups of 25 juvenile largemouth bass with initial body weight 9.51 ± 0.03 g were fed during the 56-day feeding experiment. Experimental results showed that fish fed FPH-30 obtained a significantly higher weight gain rate (WGR), specific growth rate (SGR), protein efficiency ratio (PER), and significant feed conversion rate (FCR) compared to the other three groups (P < 0.05). FPH-30 group also promoted protein synthesis and deposition, as evidenced by the higher whole-body crude protein contents, the higher expressions of GH1, IGF-1, TOR, and S6K in the liver, and SLC7A5, SLC7A8, SLC38A2, and SLC15A2 in the intestine than the other three groups. FPH-30 group could also enhance intestinal health status by increasing the activities of SOD, POD, CAT, GSH-Px, and T-AOC activities by upregulating the expressions of SOD, GSH-Px, IL1β, and TNFβ, and by reducing the MDA contents and the expressions of IL15, Caspase 3, Caspase 9, and Caspase 10 than other groups. Compared to the control group, the Actinobacteriota abundance markedly decreased in FPH treatments, while the variation tendency of the phylum Proteobacteria was opposite. The peak value of Firmicutes:Bacteroidetes ratio and the lowest of Bacteroidetes abundance were seen in largemouth bass fed FPH-30 (P < 0.05). Fish in three FPH treatments had lower abundances of opportunistic pathogens Staphylococcus and Plesiomonas than fish in the control group. In conclusion, FPH is a nutritious feed ingredient for juvenile largemouth bass, and can be added to a dietary level of 30 g/kg dry matter replacing fish meal without any negative effect on growth and feed utilization. FPH supplements could also strengthen the intestinal immune mechanisms of largemouth bass to tackle the immunodeficiency produced by fish meal replacement.

Sevoflurane-Induced Neurotoxicity in the Developing Hippocampus via HIPK2/AKT/mTOR Signaling

Sevoflurane (Sev) is a widely used inhalational anesthetic for general anesthesia in children. Previous studies have confirmed that multiple exposures to inhaled anesthetic can induce long-term neurotoxicity in newborn mice. However, the underlying mechanisms remain elusive. In this study, we investigated the role of homeodomain interacting protein kinase 2 (HIPK2), a stress activating kinase involved in neural survival and synaptic plasticity, and its underlying mechanism in sevoflurane-induced neurotoxicity. Empirical study showed that neuronal apoptosis was elevated after exposure to sevoflurane. Meanwhile, up-regulation of HIPK2 and AKT/mTOR signaling was observed in primary hippocampal neurons and hippocampus in mice upon anesthetic exposure. A64, antagonist of HIPK2, could significantly reduce increased apoptosis and activation of AKT/mTOR induced by sevoflurane. AKT antagonist MK2206 partially alleviated neuronal apoptosis without affecting the expression of HIPK2. Experimental results demonstrated a crucial role of HIPK2/AKT/mTOR signaling in neurotoxicity of sevoflurane. Thus, HIPK2/AKT/mTOR signaling can serve as a potential target for the protection of inhalation anesthesia-induced cytotoxicity in the future.

Brain-Type Glycogen Phosphorylase Is Crucial for Astrocytic Glycogen Accumulation in Chronic Social Defeat Stress-Induced Depression in Mice

Astrocytic glycogen plays an important role in brain energy metabolism. However, the contribution of glycogen metabolism to stress-induced depression remains unclear. Chronic social defeat stress was used to induce depression-like behaviors in mice, assessed with behavioral tests. Glycogen concentration in the medial prefrontal cortex (mPFC) and the expression of key enzymes of the glycogen metabolism were investigated using Western blots, immunofluorescent staining, electron microscopy, and biochemical assays. Stereotaxic surgery and viral-mediated gene transfer were applied to knockdown or overexpress brain-type glycogen phosphorylase (PYGB) in the mPFC. The glycogen content increased in the mPFC after stress. Glycogenolytic dysfunction due to inactivation of PYGB was responsible for glycogen accumulation. Behavioral tests on astrocyte-specific PYGB overexpression mice showed that augmenting astrocytic PYGB reduces susceptibility to depression when compared with stress-susceptible mice. Conversely, PYGB genetic down-regulation in the mPFC was sufficient to induce glycogen accumulation and depression-like behaviors. Furthermore, PYGB overexpression in the mPFC decreases susceptibility to depression, at least partially by rescuing glycogen phosphorylase activity to maintain glycogen metabolism homeostasis during stress. These findings indicate that (1) glycogen accumulation occurs in mice following stress and (2) glycogenolysis reprogramming leads to glycogen accumulation in astrocytes and PYGB contributes to stress-induced depression-like behaviors. Pharmacological tools acting on glycogenolysis might constitute a promising therapy for depression.

Effect of phosphorus on growth performance, intestinal tight junctions, Nrf2 signaling pathway and immune response of juvenile mirror carp (Cyprinus carpio) fed different α-ketoglutarate levels

Previous research has shown that dietary α-ketoglutarate (AKG) supplementation can promote growth performance, phosphorus metabolism, and skeletal development of juvenile mirror carp (Cyprinus carpio) fed low phosphorous diets. In the current study, we tested the hypothesis that 1% AKG dietary supplementation reduces the dietary phosphorus requirements of juvenile mirror carp. A total of 12 experimental isoproteic and isolipidic diets containing available phosphorus levels of 0.21%, 0.38%, 0.55%, 0.72%, 0.89%, and 1.07% dry matter with either 0 or 1% AKG supplementation were used in the study. A total of 1080 juvenile fish of similar initial weight (0.90 ± 0.03 g) were selected and randomly assigned to 36 tanks. There were three replicates for each experimental group, with a density of 30 fish per tank. Fish were fed to satiation for 8 weeks. The results indicated that fish fed the diet supplemented with 1% AKG showed a significant increase in final body weight (FBW), weight gain rate (WGR), feed intake (FI) and phosphorus intake (PI) compared to the diet without AKG (P < 0.05). FBW and WGR increased significantly with increasing available phosphorus levels from 0.21% to 0.89% (P < 0.05). The mRNA expression of ZO-1, claudin 11, and occludin was significantly increased by dietary AKG and phosphorus (P < 0.05). The mRNA expression of Nrf2, GPx1a, and CAT in the Nrf2 signaling pathway was significantly increased by dietary AKG and phosphorus (P < 0.05). The expression levels of IL-10 and TGF-β2 were significantly increased by dietary AKG and phosphorus, but the expression levels of IL-1β, IL-8, IL-10, TNF-a and NF-κB were significantly decreased with dietary AKG and phosphorus supplementation (P < 0.05). Based on second-order polynomial regression analysis of WGR against dietary phosphorus levels, the optimal dietary phosphorus level was found to be 0.79% of dry feed for juvenile mirror carp fed a diet with 1% AKG supplementation and 0.93% of dry feed without AKG supplementation. This study confirmed that AKG supplementation can reduce the phosphorus requirements of juvenile mirror carp by promoting growth performance, intestinal tight junctions, Nrf2 signaling pathways and immune response.

Microcystin-LR induces ferroptosis in intestine of common carp (Cyprinus carpio)

Previous studies provide comprehensive evidence of the environmental hazards and intestinal toxicity of microcystin-LR (MC-LR) exposure. However, little is known about the mechanisms underlying the injury of intestine exposed to MC-LR. Juvenile common carp (Cyprinus carpio) were exposed to MC-LR (0 and 10 μg/L) for 15 days. The results suggest that organic anion-transporting polypeptides 3a1, 4a1, 2b1, and 1d1 mediate MC-LR entry into intestinal tissues. Lesion morphological features (vacuolization, deformation and dilation of the endoplasmic reticulum [ER], absence of mitochondrial cristae in mid-intestine), up-regulated mRNA expressions of ER stress (eukaryotic translation initiation factor 2-alpha kinase 3, endoplasmic reticulum to nucleus signaling 1, activating transcription factor [ATF] 6, ATF4, DNA damage-inducible transcript 3), iron accumulation, and down-regulated activity of glutathione peroxidase (GPx) and glutathione (GSH) content were all typical characteristics of ferroptosis in intestinal tissue following MC-LR exposure. GSH levels in intestinal tissue corroborated as the most influential GSH/GPx 4- related metabolic pathway in response to MC-LR exposure. Verrucomicrobiota, Planctomycetes, Bdellovibrionota, Firmicutes and Cyanobacteria were correlated with the ferroptosis-related GSH following MC-LR exposure. These findings provide new perspectives of the ferroptosis mechanism of MC-LR-induced intestinal injury in the common carp.

Astrocytic A1/A2 paradigm participates in glycogen mobilization mediated neuroprotection on reperfusion injury after ischemic stroke

Background

Astrocytic glycogen works as an essential energy reserve for surrounding neurons and is reported to accumulate excessively during cerebral ischemia/reperfusion (I/R) injury. Our previous study found that accumulated glycogen mobilization exhibits a neuroprotective effect against I/R damage. In addition, ischemia could transform astrocytes into A1-like (toxic) and A2-like (protective) subtypes. However, the underlying mechanism behind accumulated glycogen mobilization-mediated neuroprotection in cerebral reperfusion injury and its relationship with the astrocytic A1/A2 paradigm is unknown.

Methods

Astrocytic glycogen phosphorylase, the rate-limiting enzyme in glycogen mobilization, was specifically overexpressed and knocked down in mice and in cultured astrocytes. The I/R injury was imitated using a middle cerebral artery occlusion/reperfusion model in mice and an oxygen–glucose deprivation/reoxygenation model in cultured cells. Alterations in A1-like and A2-like astrocytes and the expression of phosphorylated nuclear transcription factor-κB (NF-κB) and phosphorylated signal transducer and activator of transcription 3 (STAT3) were determined by RNA sequencing, immunofluorescence and immunoblotting. Metabolites, including glycogen, NADPH, glutathione and reactive oxygen species (ROS), were analyzed by biochemical analysis.

Results

Here, we observed that astrocytic glycogen mobilization inhibited A1-like astrocytes and enhanced A2-like astrocytes after reperfusion in an experimental ischemic stroke model in vivo and in vitro. In addition, glycogen mobilization could enhance the production of NADPH and glutathione by the pentose phosphate pathway (PPP) and reduce ROS levels during reperfusion. NF-κB inhibition and STAT3 activation caused by a decrease in ROS levels were responsible for glycogen mobilization-induced A1-like and A2-like astrocyte transformation after I/R. The astrocytic A1/A2 paradigm is closely correlated with glycogen mobilization-mediated neuroprotection in cerebral reperfusion injury.

Conclusions

Our data suggest that ROS-mediated NF-κB inhibition and STAT3 activation are the key pathways for glycogen mobilization-induced neuroprotection and provide a promising metabolic target for brain reperfusion injury in ischemic stroke.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02284-y.

MD2 contributes to the pathogenesis of perioperative neurocognitive disorder via the regulation of α5GABAA receptors in aged mice

BACKGROUND

Perioperative neurocognitive disorder (PND) is a long-term postoperative complication in elderly surgical patients. The underlying mechanism of PND is unclear, and no effective therapies are currently available. It is believed that neuroinflammation plays an important role in triggering PND. The secreted glycoprotein myeloid differentiation factor 2 (MD2) functions as an activator of the Toll-like receptor 4 (TLR4) inflammatory pathway, and α5GABA_A receptors (α5GABA_ARs) are known to play a key role in regulating inflammation-induced cognitive deficits. Thus, in this study, we aimed to investigate the role of MD2 in PND and determine whether α5GABA_ARs are involved in the function of MD2.

METHODS

Eighteen-month-old C57BL/6J mice were subjected to laparotomy under isoflurane anesthesia to induce PND. The Barnes maze was used to assess spatial reference learning and memory, and the expression of hippocampal MD2 was assayed by western blotting. MD2 expression was downregulated by bilateral injection of AAV-shMD2 into the hippocampus or tail vein injection of the synthetic MD2 degrading peptide Tat-CIRP-CMA (TCM) to evaluate the effect of MD2. Primary cultured neurons from brain tissue block containing cortices and hippocampus were treated with Tat-CIRP-CMA to investigate whether downregulating MD2 expression affected the expression of α5GABA_ARs. Electrophysiology was employed to measure tonic currents. For α5GABA_ARs intervention experiments, L-655,708 and L-838,417 were used to inhibit or activate α5GABA_ARs, respectively.

RESULTS

Surgery under inhaled isoflurane anesthesia induced cognitive impairments and elevated the expression of MD2 in the hippocampus. Downregulation of MD2 expression by AAV-shMD2 or Tat-CIRP-CMA improved the spatial reference learning and memory in animals subjected to anesthesia and surgery. Furthermore, Tat-CIRP-CMA treatment decreased the expression of membrane α5GABA_ARs and tonic currents in CA1 pyramidal neurons in the hippocampus. Inhibition of α5GABA_ARs by L-655,708 alleviated cognitive impairments after anesthesia and surgery. More importantly, activation of α5GABA_ARs by L-838,417 abrogated the protective effects of Tat-CIRP-CMA against anesthesia and surgery-induced spatial reference learning and memory deficits.

CONCLUSIONS

MD2 contributes to the occurrence of PND by regulating α5GABA_ARs in aged mice, and Tat-CIRP-CMA is a promising neuroprotectant against PND.

Activation of Orexinergic Neurons Inhibits the Anesthetic Effect of Desflurane on Consciousness State via Paraventricular Thalamic Nucleus in Rats

BACKGROUND

Orexin, a neuropeptide derived from the perifornical area of the hypothalamus (PeFLH), promotes the recovery of propofol, isoflurane, and sevoflurane anesthesias, without influencing the induction time. However, whether the orexinergic system also plays a similar role in desflurane anesthesia, which is widely applied in clinical practice owing to its most rapid onset and offset time among all volatile anesthetics, has not yet been studied. In the present study, we explored the effect of the orexinergic system on the consciousness state induced by desflurane anesthesia.

METHODS

The c-Fos staining was used to observe the activity changes of orexinergic neurons in the PeFLH and their efferent projection regions under desflurane anesthesia. Chemogenetic and optogenetic techniques were applied to compare the effect of PeFLH orexinergic neurons on the induction, emergence, and maintenance states between desflurane and isoflurane anesthesias. Orexinergic terminals in the paraventricular thalamic nucleus (PVT) were manipulated with pharmacologic, chemogenetic, and optogenetic techniques to assess the effect of orexinergic circuitry on desflurane anesthesia.

RESULTS

Desflurane anesthesia inhibited the activity of orexinergic neurons in the PeFLH, as well as the neuronal activity in PVT, basal forebrain, dorsal raphe nucleus, and ventral tegmental area, as demonstrated by c-Fos staining. Activation of PeFLH orexinergic neurons prolonged the induction time and accelerated emergence from desflurane anesthesia but only influenced the emergence in isoflurane anesthesia, as demonstrated by chemogenetic and pharmacologic techniques. Meanwhile, optical activation of orexinergic neurons exhibited a long-lasting inhibitory effect on burst-suppression ratio (BSR) under desflurane anesthesia, and the effect may be contributed by the orexinergic PeFLH-PVT circuitry. The orexin-2 receptor (OX2R), but not orexin-1 receptor (OX1R), in the PVT, which had been inhibited most significantly by desflurane, mediated the proemergence effect of desflurane anesthesia.

CONCLUSIONS

We discovered, for the first time, that orexinergic neurons in the PeFLH could not only influence the maintenance and emergence from isoflurane and desflurane anesthesias but also affect the induction under desflurane anesthesia. Furthermore, this specific effect is probably mediated by orexinergic PeFLH-PVT circuitry, especially OX2Rs in the PVT.

[Autologous stem cell transplantation improves outcomes of patients with multiple myeloma receiving proteasome inhibitors and lenalidomide treatment]

OBJECTIVE

To evaluate the effect of autologous stem cell transplantation (ASCT) on treatment response and survival outcomes in patients with newly diagnosed multiple myeloma (MM) receiving treatments with proteasome inhibitors and lenalidomide.

METHODS

We retrospectively collected the clinical data of newly diagnosed MM patients, who were eligible for ASCT and received proteasome inhibitors or lenalidomide-based treatment in our hospital from January, 2015 to December, 2019. The patients were divided into transplantation group and non-transplantation group, and in transplantation group, the patients received 4 to 6 courses of induction therapy with proteasome inhibitors or lenalidomide before ASCT, while those in the non-transplantation group received more than 8 courses of induction and consolidation therapy with proteasome inhibitors or lenalidomide-based regimens. The therapeutic efficacy and survival outcomes of the patinets were compared between the two groups.

RESULTS

A total of 105 patients were enrolled in the study, including 48 (45.7%) in transplantation group and 57 (54.3%) in non-transplantation group. The two groups were matched for gender, age and treatment response after 4 courses of induction therapy (P > 0.05). The rate of optimal response before relapse differed significantly between the two groups (P=0.000), and the patients receiving ASCT had significantly higher rates of complete response (85.4% vs 54.4%, P= 0.001) and very good partial response or better (95.8% vs 73.7%, P=0.002) than those without ASCT. At the end of follow-up, the median progression-free survival in the transplantation group was not reached, as compared with 29 months in the nontransplantation group (P=0.013). The median overall survival (OS) in the two groups was not reached, but the OS was better in the transplant group than in the non-transplant group (P=0.022).

CONCLUSION

ASCT can further improve the depth of remission and survival outcomes in patients with newly diagnosed MM receiving treatments with proteasome inhibitors and lenalidomide.

The association of metabolic health obesity with incidence of carotid artery plaque in Chinese adults

BACKGROUND AND AIMS

We aimed to evaluate the association between different obese phenotypes with carotid artery plaque (CAP) event.

METHOD AND RESULTS

The current retrospective cohort study was performed in 32,778 Chinese adults (19,221 men and 13,557 women, aged 41.9 ± 11.0 years). Obese phenotypes were assessed based on baseline body mass index (<24.0 vs. ≥24.0 kg/m²) and metabolic characteristics (health vs. unhealth). All the participants were further classified into four groups: metabolic health and normal weight (MHNW), metabolic unhealth and normal weight (MUHNW), metabolic health and overweight (MHO), and metabolic unhealth and overweight (MUHO). Ultrasound B-mode imaging was annually performed to evaluate CAP throughout the study. We have identified 2142 CAP cases during 5-year follow-up. Comparing with the MHNW group, the hazard ratios for the risk of incident CAP was 2.44 (95% CI:1.92 and 3.09) for the MUHNW group, 1.52 (95% CI:1.06 and 2.18) for the MHO group, and 1.8 (95% CI:1.4 and 2.33) for the MUHO group. The association was more pronounced in young adults (<65 y) than that in aged adults (≥65 y). Sensitivity analysis generated similar results with the main analysis.

CONCLUSION

MUHNW, MHO, and MUHO were associated with the risk of CAP.

Excessive Dietary Lipid Affecting Growth Performance, Feed Utilization, Lipid Deposition, and Hepatopancreas Lipometabolism of Large-Sized Common Carp (Cyprinus carpio)

An 82-day study was conducted to assess the effect of the dietary lipid levels on growth performance, feed utilization, lipid deposition, and hepatopancreas lipometabolism of large-sized common carp (Cyprinus carpio). Six isonitrogenous (300 g/kg protein) pelletized diets with different dietary lipid levels (30, 60, 90, 120, 150, and 180 g/kg) were fed in triplicate to fish groups with 75 individuals (with an initial mean weight of 247.00 ± 16.67 g). The results showed that there was a significant increase in weight gain (WG) rate (WGR), specific growth rate (SGR), and protein efficiency ratio (PER) as dietary lipid levels increased from 30 to 60 g/kg (p < 0.05) and then there was a decline. Feed conversion rate (FCR) was observed to be significantly lower in 60 g/kg lipid treatments (p < 0.05). Muscle crude protein contents were obtained to be significantly higher in 60 and 90 g/kg treatments (p < 0.05). The crude lipid content in the hepatopancreas increased significantly with an increase in dietary lipid levels (p < 0.05). The expression of lipoprotein lipase (LPL) and carnitine palmitoyltransferase-1 (CPT1) in the hepatopancreas was significantly downregulated with an increase in dietary lipid levels while the expression of growth hormone (GH), insulin-like growth factor-1 (IGF-1), fatty acid synthase (FAS), acetyl-CoA carboxylase-1 (ACC-1), and sterol regulatory element binding protein (SREBP) was upregulated first in 30 and 60 g/kg lipid treatments and then downregulated significantly in other treatments. The results revealed that excess dietary lipid supplements (more than 60 g/kg) would inhibit WG and would aggravate the lipid decomposition in the hepatopancreas. Based on WGR and FCR, the dietary lipid levels of 59.5 and 70.4 g/kg were optimal for growth performance and feed utilization of large-sized common carp.

Evaluation of Alpha-Ketoglutarate Supplementation on the Improvement of Intestinal Antioxidant Capacity and Immune Response in Songpu Mirror Carp (Cyprinus carpio) After Infection With Aeromonas hydrophila

As an intermediate substance of the tricarboxylic acid cycle and a precursor substance of glutamic acid synthesis, the effect of alpha-ketoglutarate on growth and protein synthesis has been extensively studied. However, its prevention and treatment of pathogenic bacteria and its mechanism have not yet been noticed. To evaluate the effects of alpha-ketoglutarate on intestinal antioxidant capacity and immune response of Songpu mirror carp, a total of 360 fish with an average initial weight of 6.54 ± 0.08 g were fed diets containing alpha-ketoglutarate with 1% for 8 weeks. At the end of the feeding trial, the fish were challenged with Aeromonas hydrophila for 2 weeks. The results indicated that alpha-ketoglutarate supplementation significantly increased the survival rate of carp after infection with Aeromonas hydrophila (P < 0.05), and the contents of immune digestion enzymes including lysozyme, alkaline phosphatase and the concentration of complement C4 were markedly enhanced after alpha-ketoglutarate supplementation (P < 0.05). Also, appropriate alpha-ketoglutarate increased the activities of total antioxidant capacity and catalase and prevented the up-regulation in the mRNA expression levels of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1β, interleukin-6, and interleukin-8 (P < 0.05). Furthermore, the mRNA expression levels of toll-like receptor 4 (TLR4), and nuclear factor kappa-B (NF-κB) were strikingly increased after infection with Aeromonas hydrophila (P < 0.05), while the TLR4 was strikingly decreased with alpha-ketoglutarate supplementation (P < 0.05). Moreover, the mRNA expression levels of tight junctions including claudin-1, claudin-3, claudin-7, claudin-11 and myosin light chain kinases (MLCK) were upregulated after alpha-ketoglutarate supplementation (P < 0.05). In summary, the appropriate alpha-ketoglutarate supplementation could increase survival rate, strengthen the intestinal enzyme immunosuppressive activities, antioxidant capacities and alleviate the intestinal inflammation, thereby promoting the intestinal immune responses and barrier functions of Songpu mirror carp via activating TLR4/MyD88/NF-κB and MLCK signaling pathways after infection with Aeromonas hydrophila.

Copper stimulates neonicotinoid insecticide thiacloprid degradation by Ensifer adhaerens TMX-23

AIMS

Aims of this study are to elucidate the molecular mechanism of copper-improved thiacloprid (THI) degradation by Ensifer adhaerens TMX-23 and characterize copper resistance of this strain.

METHODS AND RESULTS

Resting cells of E. adhaerens TMX-23 were used to degrade THI, with formation of THI amide and 98·31% of 0·59 mmol l^-1 THI was degraded in 100 min. The addition of copper improved the degradation of THI and showed little inhibitory effects on the growth of E. adhaerens TMX-23. E. adhaerens TMX-23 degraded THI to THI amide by nitrile hydratases (NhcA and NhpA). QPCR analysis indicated that the expression of nhpA was up-regulated in the presence of copper. E. adhaerens TMX-23 nitrile hydratases were purified, and enzyme assay of NhpA exhibited the highest NHase activity toward THI. The addition of copper activated the activity of NhcA. Soil degradation experiment indicated that E. adhaerens TMX-23 could quickly eliminate THI residual in copper-added soil.

CONCLUSIONS

Copper improved THI degradation by E. adhaerens TMX-23 was attributed to the induced expression of nhpA and activated NhcA.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study broadens the investigation of regulatory mechanism of NHase expression and provided theoretical basis for using metal-resistant microbes to degrade pesticide in heavy metal co-contaminated environments.

Impact of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on the outcomes in patients with refractory lung cancer

Background

PD-1/PD-L1 inhibitors in combination with chemotherapy are widely used in clinical practice. However, the ideal combined timing of them has not been fully explored.

Methods

In this study, simulation experiments to explore the impacts of the combination of anti-PD-1 antibody (anti-PD-1 Ab) on the cytotoxic effects of chemotherapeutic drugs in peripheral blood mononuclear cells were performed. In addition, the effects of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on efficacy and safety were retrospectively analysed in patients with refractory lung cancer.

Results

Experiments in vitro showed that administering the anti-PD-1 Ab 3 days after chemotherapy (represented by dicycloplatin) resulted in significantly weaker cytotoxic effects on lymphocytes, compared with administering the anti-PD-1 Ab before or concurrent with chemotherapy. Moreover, data from 64 lung cancer patients treated with PD-1/PD-L1 inhibitors plus chemotherapy as a second- or higher-line therapy were retrospectively analysed. The results showed that administering PD-1/PD-L1 inhibitors 1-10 days (especially 3-5 days) after chemotherapy was associated with longer overall survival [17.3 months versus 12.7 months; hazard ratio (HR) = 0.58, 95% confidence interval (CI) 0.28-1.19, P = 0.137 in univariate analysis; HR = 0.36, 95% CI 0.16-0.80, P = 0.012 in multivariate analysis] and a trend of improved progression-free survival (5.1 months versus 4.2 months; HR = 0.81, 95% CI 0.42-1.54, P = 0.512) compared with administering PD-1/PD-L1 inhibitors before or concurrent with chemotherapy.

Conclusion

Our findings suggest that administering PD-1/PD-L1 inhibitors 1-10 days (especially 3-5 days) after chemotherapy is superior to administering PD-1/PD-L1 inhibitors before or concurrent with chemotherapy in patients with refractory lung cancer, but this result needs to be further explored by prospective studies.

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The cytotoxic effects of chemotherapeutic drugs were positively correlated with the activation states of PBMCs.

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Administering the anti-PD-1 Ab 3 days after chemotherapy resulted in weaker cytotoxic effects on lymphocytes in vitro.

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Administering PD-1/PD-L1 inhibitors a few days after chemotherapy resulted in better survival in lung cancer patients.

Genetically encoded light-up RNA aptamers and their applications for imaging and biosensing

Intracellular small ligands and biomacromolecules are playing crucial roles not only as executors but also as regulators. It is essential to develop tools to investigate their dynamics to interrogate their functions and reflect the cellular status. Light-up RNA aptamers are RNA sequences that can bind with their cognate nonfluorescent fluorogens and greatly activate their fluorescence. The emergence of genetically encoded light-up RNA aptamers has provided fascinating tools for studying intracellular small ligands and biomacromolecules owing to their high fluorescence activation degree and facile programmability. Here we review the burgeoning field of light-up RNA aptamers. We first briefly introduce light-up RNA aptamers with a focus on the photophysical properties of the fluorogens. Then design strategies of genetically encoded light-up RNA aptamer based sensors including turn-on, signal amplification and ratiometric rationales are emphasized.

In vivo mRNA imaging based on tripartite DNA probe mediated catalyzed hairpin assembly

Herein, we develop a novel tripartite DNA probe to transport phosphorothioated substrate hairpins and an aptamer for the intramolecular CHA circuit, which achieves detection of a low amount of specific mRNA in living cells and mice. Our study provides an improved strategy to promote in vivo fluorescence imaging applications in early-stage clinical diagnosis.

95 Invitro correction of F508del and G542X mutations in sheep fibroblasts of cystic fibrosis models

Cystic fibrosis (CF) is a human genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. Among the ∼2000 known CF mutations, the F508del mutation is found in 84% and G542X in 4.6% of the CF patients in the United States. The F508del mutation occurs in exon 11 and is characterised by deletion of the “CTT” nucleotides, resulting in deletion on the phenylalanine residue at the position 508 of CFTR. This causes misfolding of the CFTR protein, which is further degraded by proteases. The G542X mutation is a nonsense mutation found in exon 12 and associated with nonsense-mediated decay of the mutant transcript causing the absence of protein production. Previously, we generated CFTRF508del/F508del and CFTRG542X/G542X lambs (unpublished) using CRISPR/Cas9 and somatic cell nuclear transfer (SCNT) techniques. We hypothesised that gene editing may be an effective tool to correct these mutations and permanently cure this genetic disease. Thus, in this study, we evaluated the efficiency of CRISPR/Cas9-meditated gene knock-in to correct the F508del and G542X mutations in sheep fibroblasts invitro. We designed single guide (sg)RNAs using the Benchling software (https://benchling.com/academic) and approximately 100bp of single-stranded oligodeoxynucleotides (ssODNs) targeting the mutation sites at exon 11 and 12 to introduce either “CTT” or change the “T” to “G” nucleotide in genome of F508del or G542X CF sheep cells, respectively. Each of Cas9/sgRNA ribonucleoproteins was transfected into sheep fibroblast cells along with ssODNs using the Lonza-4D-NucleofectorTM (Lonza) system for homology-directed repair. The transfected cells were subsequently cultured in Dulbecco’s modified Eagle medium, supplemented with 15% fetal bovine serum and 1% penicillin, and incubated at 38.5°C. DNA was extracted 48h post-transfection to validate mutation efficiency. PCR products of the exons 11 and 12 were ligated into T-vector, and bacterial colonies were selected based on blue/white screening. In total, we isolated 32 single cell bacterial colonies for each mutant. Sequencing results indicate that “CTT” was introduced in 4/26 (15.3%) plasmid colonies, and “T to G” replaced in 13/31 (41.9%) colonies. Therefore, our results indicate that the F508del and G542X mutations can be effectively corrected in CF sheep fibroblasts invitro using a CRISPR/Cas9 approach.