Rhein: A potent immunomodulator empowering largemouth bass against MSRV infection.

Micropterus salmoides rhabdovirus (MSRV) is a significant viral pathogen in largemouth bass aquaculture, causing substantial annual economic losses. However, effective prevention methods remain elusive for various reasons. Medicinal plant extracts have emerged as valuable tools in preventing and managing aquatic animal diseases. Thus, the search for immunomodulators with straightforward, safe structures in plant extracts is imperative to ensure the continued health and growth of the largemouth bass industry. In our research, we employed epithelioma papulosum cyprinid (EPC) cells and largemouth bass as models to assess the anti-MSRV properties and immunomodulatory effects of ten plant-derived bioactive compounds. Among them, rhein demonstrated noteworthy potential, exhibiting a 75 % reduction in viral replication in vitro at a concentration of 50 mg/L. Furthermore, rhein pre-treatment significantly inhibited MSRV genome replication in EPC cells, with the highest inhibition rate reaching 64.8 % after 24 h, underscoring rhein's preventive impact against MSRV. Likewise, rhein displayed remarkable therapeutic effects on EPC cells during the early stages of MSRV infection, achieving a maximum inhibition rate of 85.6 % in viral replication. Subsequent investigations unveiled that rhein, with its consistent activity, effectively mitigated cytopathic effects (CPE) and nuclear damage induced by MSRV infection. Moreover, it restrained mitochondrial membrane depolarization and reduced the apoptosis rate by 38.8 %. In vivo experiments reinforced these findings, demonstrating that intraperitoneal injection of rhein enhanced the expression levels of immune related genes in multiple organs, hindered virus replication, and curtailed the mortality rate of MSRV-infected largemouth bass by 29 %. Collectively, our study endorses the utility of rhein as an immunomodulator to combat MSRV infections in largemouth bass. This not only underscores the potential of rhein as a broad-spectrum antiviral and means to bolster the immune response but also highlights the role of apoptosis as an immunological marker, making it an invaluable addition to the armamentarium against aquatic viral pathogens.

Synthesis and anti-parasites efficacy of coumarin derivatives against Dactylogyrus intermedius.

Dactylogyrus is one of the most common parasitic diseases in fish and causes huge losses to the aquaculture industry. With the advantages of safety, low toxicity and easy degradation, plant-derived drugs are ideal for the creation of green aquatic ingredients. The use of plant-derived drugs in aquaculture is limited by their low content and high processing costs, which is a challenge that can be solved by the chemical synthesis of plant-derived drugs. Eleven new coumarin derivatives were synthesized and assessed for their anthelmintic activity in this study. Among them, the derivative 7-((1-tosyl-1H-1,2,3-triazol-4-yl)methoxy)-2H-chromen-2-one (N11) has good anthelmintic activity and its mean anthelmintic efficacy against D. intermedius at a concentration of 10 µM reached 99.84%, which is even better than the anthelmintic activity of the positive control mebendazole. Further studies showed that N11 had concentration values of 3.31 and 1.94 µM for 50% maximal effect (EC50 ) against D. intermedius at 24 and 48 h, respectively. Furthermore, scanning electron microscopy revealed that N11 caused damage to D. intermedius. What is more noteworthy is that a substantial reduction in the ATP content of the parasite was observed following in vitro and in vivo administration of N11. Moreover, it was also found that N11 was able to inhibit the horizontal transmission of D. intermedius. Furthermore, real-time quantitative PCR analysis was utilized to determine the expression profile of genes associated with anti-inflammatory cytokines (IL-10, TGF-ß and IL-4) in goldfish. In all examined organs, it was observed that the expression of anti-inflammatory cytokines increased subsequent to treatment with N11, according to the results. Thus, these results all suggest that N11 possesses good anthelmintic activity and is a potentially effective agent for the control of D. intermedius.

Herbal active small molecule as an immunomodulator for potential application on resistance of common carp against SVCV infection.

Herbal immunomodulators are an important part of prevention and control on viral diseases in aquaculture because of their propensity to improve immunity in fish. The present study was conducted to evaluate the immunomodulatory effect and antiviral activity of a synthesized derivative (serial number: LML1022) against spring viremia of carp virus (SVCV) infection in vitro and in vivo. The antiviral data suggested that LML1022 at 100 µM significantly inhibited the virus replication in epithelioma papulosum cyprini (EPC) cells, and may completely inhibit the infectivity of SVCV virion particles to fish cells by affecting the viral internalization. The results in the related stability of water environments also demonstrated that LML1022 had an inhibitory half-life of 2.3 d at 15 °C, which would facilitate rapid degradation of LML1022 in aquaculture application. For in vivo study, the survival rate of SVCV-infected common carp was increased 30% at least under continuous oral injection of LML1022 at 2.0 mg/kg for 7 d treatment. Additionally, pretreatment of LML1022 on fish prior to SVCV infection also obviously reduced the viral loads in vivo as well as an improved survival rate, showing that LML1022 was potential as an immunomodulator. As an immune response, LML1022 significantly upregulated the immune-related gene expression including IFN-γ2b, IFN-I, ISG15 and Mx1, indicating that its dietary administration may improve the resistance of common carp against SVCV infection.

Two-level mixed-effects height to crown base model for moso bamboo (Phyllostachys edulis) in Eastern China.

Height to crown base (HCB) is an important predictor variable for forest growth and yield models and is of great significance for bamboo stem utilization. However, existing HCB models built so far on the hierarchically structured data are for arbor forests, and not applied to bamboo forests. Based on the fitting of data acquired from 38 temporary sample plots of Phyllostachys edulis forests in Yixing, Jiangsu Province, we selected the best HCB model (logistic model) from among six basic models and extended it by integrating predictor variables, which involved evaluating the impact of 13 variables on HCB. Block- and sample plot-level random effects were introduced to the extended model to account for nested data structures through mixed-effects modeling. The results showed that bamboo height, diameter at breast height, total basal area of all bamboo individuals with a diameter larger than that of the subject bamboo, and canopy density contributed significantly more to variation in HCB than other variables did. Introducing two-level random effects resulted in a significant improvement in the accuracy of the model. Different sampling strategies were evaluated for response calibration (model localization), and the optimal strategy was identified. The prediction accuracy of the HCB model was substantially improved, with an increase in the number of bamboo samples in the calibration. Based on our findings, we recommend the use of four randomly selected bamboo individuals per sample to provide a compromise between measurement cost, model use efficiency, and prediction accuracy.

Bifidobacterium longum supplementation improves age-related delays in fracture repair.

Age-related delays in bone repair remains an important clinical issue that can prolong pain and suffering. It is now well established that inflammation increases with aging and that this exacerbated inflammatory response can influence skeletal regeneration. Recently, simple dietary supplementation with beneficial probiotic bacteria has been shown to influence fracture repair in young mice. However, the contribution of the gut microbiota to age-related impairments in fracture healing remains unknown. Here, we sought to determine whether supplementation with a single beneficial probiotic species, Bifidobacterium longum (B. longum), would promote fracture repair in aged (18-month-old) female mice. We found that B. longum supplementation accelerated bony callus formation which improved mechanical properties of the fractured limb. We attribute these pro-regenerative effects of B. longum to preservation of intestinal barrier, dampened systemic inflammation, and maintenance of the microbiota community structure. Moreover, B. longum attenuated many of the fracture-induced systemic pathologies. Our study provides evidence that targeting the gut microbiota using simple dietary approaches can improve fracture healing outcomes and minimize systemic pathologies in the context of aging.

N2-Selective ß-Thioalkylation of Benzotriazoles with Alkenes.

Herein, N2-selective ß-thioalkylation of benzotriazoles with unactivated alkenes and styrenes is reported. The N2-selective ß-thioalkylation of benzotriazoles is highly stereospecific and works under simple and mild conditions, exhibiting excellent functional group tolerance. The high N2-selectivity is a consequence of the combination of hydrogen bonding and Lewis acid/base activation, which reverses the N2-position to be favored for alkylation.

Sexually Dimorphic Increases in Bone Mass Following Tissue-specific Overexpression of Runx1 in Osteoclast Precursors.

Many metabolic bone diseases arise as a result excessive osteoclastic bone resorption, which has motivated efforts to identify new molecular targets that can inhibit the formation or activity of these bone-resorbing cells. Mounting evidence indicates that the transcription factor Runx1 acts as a transcriptional repressor of osteoclast formation. Prior studies using a conditional knockout approach suggested that Runx1 in osteoclast precursors acts as an inhibitor of osteoclastogenesis; however, the effects of upregulation of Runx1 on osteoclast formation remain unknown. In this study, we investigated the skeletal effects of conditional overexpression of Runx1 in preosteoclasts by crossing novel Runx1 gain-of-function mice (Rosa26-LSL-Runx1) with LysM-Cre transgenic mice. We observed a sex-dependent effect whereby overexpression of Runx1 in female mice increased trabecular bone microarchitectural indices and improved torsion biomechanical properties. These effects were likely mediated by delayed osteoclastogenesis and decreased bone resorption. Transcriptomics analyses during osteoclastogenesis revealed a distinct transcriptomic profile in the Runx1-overexpressing cells, with enrichment of genes related to redox signaling, apoptosis, osteoclast differentiation, and bone remodeling. These data further confirm the antiosteoclastogenic activities of Runx1 and provide new insight into the molecular targets that may mediate these effects.

Deletion of IL-17ra in osteoclast precursors increases bone mass by decreasing osteoclast precursor abundance.

Metabolic bone diseases, such as osteoporosis, typically reflect an increase in the number and activity of bone-resorbing osteoclasts that result in a loss of bone mass. Inflammatory mediators have been identified as drivers of both osteoclast formation and activity. The IL-17 family of inflammatory cytokines has gained attention as important contributors to both bone formation and resorption. The majority of IL-17 cytokines signal through receptor complexes containing IL-17a receptor (IL-17ra); however, the role of IL-17ra signaling in osteoclasts remains elusive. In this study, we conditionally deleted Il17ra in osteoclast precursors using LysM-Cre and evaluated the phenotypes of skeletally mature male and female conditional knockout and control mice. The conditional knockout mice displayed an increase in trabecular bone microarchitecture in both the appendicular and axial skeleton. Assessment of osteoclast formation in vitro revealed that deletion of Il17ra decreased osteoclast number, which was confirmed in vivo using histomorphometry. This phenotype was likely driven by a lower abundance of osteoclast precursors in IL-17ra conditional knockout mice. This study suggests that IL-17ra signaling in preosteoclasts can contribute to osteoclast formation and subsequent bone loss.

Potential application of antiviral coumarin in aquaculture against IHNV infection by reducing viral adhesion to the epithelial cell surface.

Due to the lack of relevant therapies for infectious haematopoietic necrosis virus (IHNV) infection, the viral outbreak invariably causes serious economic losses in salmonid species. In this study, we evaluated the anti-IHNV effects of 7-(6-benzimidazole) coumarin (C10) and 4-phenyl-2-thioxo-1,2,3,4-tetrahydro-5H-chromeno[4,3-d]pyrimidin-5-one (S5) in vitro and in vivo. The results revealed that C10 at 12.5 mg/L and S5 at 25 mg/L significantly inhibited IHNV replication in epithelioma papulosum cyprini (EPC) cells with a maximum inhibitory rate >90%, showing that IHNV-induced cytopathic effect (CPE) was alleviated by C10 and S5. There are two complementary effects on antiviral mechanism: 1. C10 completely inhibited IHNV infectivity when the virus was preincubated with C10 at 12.5 mg/L, determining that C10 may have a negative impact on IHNV binding to the cell; 2. C10 also up-regulated the gene expression of extracellular proto type galectin-1 (Gal1-L2) and a chimera galectin-3 (Gal3-L1) of EPC cells to inhibit IHNV adhesion. For the in vivo study, injection and immersion of the coumarins enhanced the survival rate of rainbow trout (Oncorhynchus mykiss) juveniles by 25% (at least) at 12 dpi. IHNV loads in the kidney and spleen were also obviously decreased at 96 h, and thus we considered that they had a delaying effect on IHNV replication in vivo. Meanwhile, C10 with a high stability in aquacultural water in immersion suppressed IHNV horizontal transmission by decreasing the viral loads in recipient fish. Overall, our data suggest that there is a positive effect of C10 and S5 against IHNV infection in aquaculture, and C10 had the potential to be a broad-spectrum antiviral against fish rhabdoviruses.

In vitro and in vivo evaluation of antiviral activity of a phenylpropanoid derivative against spring viraemia of carp virus.

Phenylpropanoids, common natural compounds, possess many different biological activities such as antioxidant, anti-inflammatory and antiviral. Spring viraemia of carp virus (SVCV) can cause a high mortality in common carp (Cyprinus carpio). However, there are currently no licenced drugs that effectively cure this disease. In this study, we designed and synthesized a phenylpropanoid derivative 4-(4-methoxyphenyl)-3,4-dihydro-2H-chromeno[4,3-d]pyrimidine-2,5(1 H)-dione (E2), and explored the antiviral effect against SVCV in vitro and in vivo. Up to 25 mg/L of E2 significantly inhibited the expression levels of SVCV protein genes in the epithelioma papulosum cyprini (EPC) cell line by a maximum inhibitory rate of >90%. As expected, E2 remarkably declined the apoptotic of SVCV-infected cells and suppressed potential enhancement of the mitochondrial membrane potential (ΔΨm), these data implied that E2 could protect mitochondria from structural damage in response to SVCV. Meanwhile, E2 was added to EPC cells under four different conditions: time-of-addition, time-of-removal, pre-treatment of viruses and pre-treatment of cells indicated that E2 may block the post-entry transport process of the virus. Additionally, the up-regulation of six interferon (IFN)-related genes also demonstrated that E2 indirectly activated IFNs for the clearance of SVCV in common carp. Drug cure effect showed that treatment with E2 at 0.5 d post infection (dpi) is more effective than at 0, 1 or 2 dpi. Most importantly, intraperitoneal therapy of E2 markedly improved common carp survival rate and reduced virus copies in body. Therefore, the E2 has potential to be developed into a novel anti-SVCV agent.

Bifidobacterium adolescentis supplementation attenuates fracture-induced systemic sequelae.

The gut microbiota is an important contributor to both health and disease. While previous studies have reported on the beneficial influences of the gut microbiota and probiotic supplementation on bone health, their role in recovery from skeletal injury and resultant systemic sequelae remains unexplored. This study aimed to determine the extent to which probiotics could modulate bone repair by dampening fracture-induced systemic inflammation. Our findings demonstrate that femur fracture induced an increase in gut permeability lasting up to 7 days after trauma before returning to basal levels. Strikingly, dietary supplementation with Bifidobacterium adolescentis augmented the tightening of the intestinal barrier, dampened the systemic inflammatory response to fracture, accelerated fracture callus cartilage remodeling, and elicited enhanced protection of the intact skeleton following fracture. Together, these data outline a mechanism whereby dietary supplementation with beneficial bacteria can be therapeutically targeted to prevent the systemic pathologies induced by femur fracture.

Hydroxycoumarin efficiently inhibits spring viraemia of carp virus infection in vitro and in vivo.

Spring viremia of carp virus (SVCV) causes devastating losses in aquaculture. Coumarin has an advantageous structure for the design of novel antiviral agents with high affinity and specificity. In this study, we evaluated a hydroxycoumarin medicine, i.e., 7-(6-benzimidazole) coumarin (C10), regarding its anti-SVCV effects in vitro and in vivo. Results showed that up to 12.5 mg/L C10 significantly inhibited SVCV replication in the epithelioma papulosum cyprini (EPC) cell line, with a maximum inhibitory rate of >97%. Furthermore, C10 significantly reduced cell death and relieved cellular morphological damage in SVCV-infected cells. Decreased mitochondrial membrane potential (ΔΨm) also suggested that C10 not only protected mitochondria, but also reduced apoptosis in SVCV-infected cells. For in vivo studies, intraperitoneal injection of C10 resulted in an anti-SVCV effect and substantially enhanced the survival rate of virus-infected zebrafish. Furthermore, C10 significantly enhanced antioxidant enzyme activities and decreased reactive oxygen species (ROS) to maintain antioxidant-oxidant balance within the host, thereby contributing to inhibition of SVCV replication. The up-regulation of six interferon (IFN)-related genes also demonstrated that C10 indirectly activated IFNs for the clearance of SVCV in zebrafish. This was beneficial for the continuous maintenance of antiviral effects because of the low viral loads in fish. Thus, C10 is suggested as a therapeutic agent with great potential against SVCV infection in aquaculture.

Evaluation on the antiviral effect of a hydroxycoumarin against infectious hematopoietic necrosis virus infection in vitro and in vivo.

Infectious hematopoietic necrosis (IHN) caused by the viral pathogen infectious hematopoietic necrosis virus (IHNV) is a highly contagious disease of salmonid species, resulting in significant economic impact. The previous study showed a hydroxycoumarin derivative 7-[6-(2-methylimidazole) hexyloxy] coumarin (D5) significantly inhibited spring viraemia of carp virus (SVCV) infection, suggesting that D5 may be useful as a potential anti-IHNV agent. In this study, D5 at the concentration of up to 10 mg/L significantly inhibited IHNV replication in epithelioma papulosum cyprini (EPC) cells with a maximum inhibitory rate of >90%, maintained mitochondrial membrane potential (ΔΨm) levels, and decreased IHNV-induced apoptosis in virus-infected cells. As the consequence of protection on mitochondria, D5 enhanced antioxidant enzyme activities and decreased reactive oxygen species (ROS) to maintain the antioxidant-oxidant balance of IHNV-infected EPC cells. For in vivo study, D5 via intraperitoneal injection exhibited an anti-IHNV effect in the virus-infected fish by substantially enhancing the survival rate. Meanwhile, up-regulation of six interferon (IFN) related gene expressions demonstrated that D5 may activate IFN-related expressions for inhibiting IHNV replication during the early stage of viral infection, which is beneficial for the continuous antiviral action on controlling low viral loads in rainbow trout juvenile. Thus, D5 effective regulated IHNV-induced undesirable conditions to be an excellent potential therapeutic agent against IHNV infection.

Effects of Rhizome Integration on the Water Physiology of Phyllostachys edulis Clones Under Heterogeneous Water Stress.

Water is crucial to plant growth and development. Under heterogeneous environmental water deficiency, physiological integration of the rhizomatous clonal plant triggers a series of physiological cascades, which induces both signaling and physiological responses. It is known that the rhizome of Phyllostachys edulis, which connects associated clonal ramets, has important significance in this physiological integration. This significance is attributed to the sharing of water and nutrients in the vascular bundle of clonal ramets under heterogeneous water conditions. However, the physiological characteristics of physiological integration under heterogeneous water stress remain unclear. To investigate these physiological characteristics, particularly second messenger Ca2+ signaling characteristics, long-distance hormone signaling molecules, antioxidant enzyme activity, osmotic adjustment substance, and nitrogen metabolism, ramets with a connected (where integration was allowed to take place) and severed rhizome (with no integration) were compared in this study. The vascular bundle structure of the rhizome was also observed using laser confocal microscopy. Overall, the results suggest that interconnected rhizome of P. edulis can enhance its physiological function in response to drought-induced stress under heterogeneous water deficiency. These measured changes in physiological indices serve to improve the clonal ramets' drought adaptivity through the interconnected rhizome.

Diamine-mediated N2-selective ß-selenoalkylation of triazoles with alkenes.

A N2-selective ß-selenoalkylation of 1,2,3-triazoles with alkenes mediated by diamines has been developed. The reaction proceeds presumably via the interaction of diamines with both the triazole moiety and selenium/alkene complex to construct a U-shaped reaction intermediate. This activation mode will block the N1 position on triazoles and thus favor the N2-selective selenoamination. This stereospecific anti-addition method enables an efficient N2-selective ß-selenoalkylation of 1,2,3-triazoles under mild and open-air conditions and might find applications in the synthesis of biologically active molecules.

Deletion of Wnt5a in osteoclasts results in bone loss through decreased bone formation.

Bone remodeling is achieved through the coupled activities of osteoclasts and osteoblasts that are controlled by many locally generated secreted factors, including WNT5A. While previous studies have demonstrated that osteoblast-derived WNT5A promotes osteoclastogenesis, the function of osteoclast-derived WNT5A on bone remodeling has remained unexplored. We examined the effects of osteoclast-derived WNT5A on bone homeostasis by utilizing the Cathepsin K-Cre (Ctsk-Cre) mouse to conditionally delete Wnt5a in mature osteoclasts. These mice exhibited reduced trabecular and cortical bone. The low bone-mass phenotype was driven by decreased bone formation, not osteoclast-mediated bone resorption, as osteoclast number and serum CTX marker were unchanged. Furthermore, molecular analysis of osteoclast- and osteoblast-derived WNT5A identified a serine-phosphorylated WNT5A that is unique to RANKL-treated macrophages mimicking osteoclasts. This study suggests a new paradigm in which WNT5A has opposing effects on bone remodeling that are dependent on the cell of origin, an effect that may result from cell type-specific differential posttranslational modifications of WNT5A.

Antiviral efficiency of a coumarin derivative on spring viremia of carp virus in vivo.

Spring viraemia of carp (SVC) in aquaculture is challenging because there are few preventative measures and/or treatments. The previous study demonstrated that an antiviral coumarin derivative, 7-(4-(4-methyl-imidazole))-coumarin (C2), inhibits spring viremia of carp virus (SVCV) infection by targeting Nrf2-ARE signaling pathway in fish cells. Thus, we hypothesized whether C2 may be used as a potential therapeutic agent for controlling SVCV infection in aquaculture. In this study, SVCV infectivity was significantly inhibited in vitro in a dose-dependent manner by preincubation with C2. C2 was verified against SVCV in zebrafish, in which the mortality and viral titer in fish body were decreased. Like other coumarins, C2 was stable with a prolonged inhibitory half-life (3.5 days) at 15 °C in the early stage of SVCV infection. The results show that horizontal transmission of SVCV was reduced by C2 in a static cohabitation challenge model, especially for recipient fish in injection treatment, which suggested that C2 may be suitable as a possible therapeutic agent for SVCV in aquaculture. Overall, this study provides the new insight that a small molecule antiviral drug can be used to control rhabdovirus infection in fish aquacultures.

Bamboo vs. crops: an integrated emergy and economic evaluation of using bamboo to replace crops in south Sichuan Province, China.

Based on long-term monitoring conducted in Chang-ning county, a pilot site of the 'Grain for Green Program' (GFGP), an integrated emergy and economic method was applied to evaluate the dynamic ecological-economic performance of 3 kinds of bamboo systems planted on sloping farmland. The results confirmed the positive effects of all 3 kinds of bamboo systems on water conservation and soil erosion control. The benefits gained progressively increased during the first 8 years after conversion, going from 4639 to 16127 EMyuan/ha/yr on average. All three bamboo plantations were much more sustainable than common agricultural crops planted on sloping land (CP) on both the short and long-term scales with their Emergy Sustainability Index (ESI) and Emergy Index for Sustainable Development (EISD), respectively, being 14.07-325.71 and 80.35-265.80 times that of CP. However, all 3 bamboo plantations had a Net Economic Benefit (NEB) less than that of CP during the first 8 years after conversion. Even with the government-mandated ecological compensation applied, the annual NEBECs of the Bambusa rigida (BR) and Phyllostachys pubescense (PP) plantations were, respectively, 3922.03 and 7422.77 yuan/ha/yr lower than the NEB of CP. Emergy-based evaluation of ecosystem services provides an objective reference for applying ecological compensation in strategy-making, but it cannot wholly solve the economic viability problem faced by all bamboo plantations. Inter-planting annual herbs or edible fungus, such as Dictyophora echinovolvata, within bamboo forests, especially in young bamboo plantations, might be a direction for optimizing bamboo cultivation that would improve its economic viability.