Histone Acetyltransferase p300 Induces De Novo Super-Enhancers to Drive Cellular Senescence.

Accumulation of senescent cells during aging contributes to chronic inflammation and age-related diseases. While senescence is associated with profound alterations of the epigenome, a systematic view of epigenetic factors in regulating senescence is lacking. Here, we curated a library of short hairpin RNAs for targeted silencing of all known epigenetic proteins and performed a high-throughput screen to identify key candidates whose downregulation can delay replicative senescence of primary human cells. This screen identified multiple new players including the histone acetyltransferase p300 that was found to be a primary driver of the senescent phenotype. p300, but not the paralogous CBP, induces a dynamic hyper-acetylated chromatin state and promotes the formation of active enhancer elements in the non-coding genome, leading to a senescence-specific gene expression program. Our work illustrates a causal role of histone acetyltransferases and acetylation in senescence and suggests p300 as a potential therapeutic target for senescence and age-related diseases.

SALT OVERLY SENSITIVE 1 is inhibited by clade D Protein phosphatase 2C D6 and D7 in Arabidopsis thaliana.

The salt overly sensitive (SOS) pathway is essential for maintaining sodium ion homeostasis in plants. This conserved pathway is activated by a calcium signaling-dependent phosphorylation cascade. However, the identity of the phosphatases and their regulatory mechanisms that would deactivate the SOS pathway remain unclear. In this study, we demonstrate that PP2C.D6 and PP2C.D7, which belong to clade D of the protein phosphatase 2C (PP2C) subfamily in Arabidopsis thaliana, directly interact with SOS1 and inhibit its Na+/H+ antiporter activity under non-salt-stress conditions. Upon salt stress, SOS3-LIKE CALCIUM-BINDING PROTEIN8 (SCaBP8), a member of the SOS pathway, interacts with the PP2Cs and suppresses their phosphatase activity; simultaneously, SCaBP8 regulates the subcellular localization of PP2C.D6 by releasing it from the plasma membrane. Thus, we identified two negative regulators of the SOS pathway that repress SOS1 activity under nonstress conditions. These processes set the stage for the activation of SOS1 by the kinase SOS2 to achieve plant salt tolerance. Our results suggest that reversible phosphorylation/dephosphorylation is crucial for the regulation of the SOS pathway, and that calcium sensors play dual roles in activating/deactivating SOS2 and PP2C phosphatases under salt stress.

Spatial risk of Haemaphysalis longicornis borne Dabieshan tick virus (DBTV) in China.

The uncertainty and unknowability of emerging infectious diseases have caused many major public health and security incidents in recent years. As a new tick-borne disease, Dabieshan tick virus (DBTV) necessitate systematic epidemiological and spatial distribution analysis. In this study, tick samples from Liaoning Province were collected and used to evaluate distribution of DBTV in ticks. Outbreak points of DBTV and the records of the vector Haemaphysalis longicornis in China were collected and used to establish a prediction model using niche model combined with environmental factors. We found that H. longicornis and DBTV were widely distributed in Liaoning Province. The risk analysis results showed that the DBTV in the eastern provinces of China has a high risk, and the risk is greatly influenced by elevation, land cover, and meteorological factors. The risk geographical area predicted by the model is significantly larger than the detected positive areas, indicating that the etiological survey is seriously insufficient. This study provided molecular and important epidemiological evidence for etiological ecology of DBTV. The predicted high-risk areas indicated the insufficient monitoring and risk evaluation and the necessity of future monitoring and control work.

High-efficiency prime editing enables new strategies for broad-spectrum resistance to bacterial blight of rice.

Using genetic resistance against bacterial blight (BB) caused by Xanthomonas oryzae pathovar oryzae (Xoo) is a major objective in rice breeding programmes. Prime editing (PE) has the potential to create novel germplasm against Xoo. Here, we use an improved prime-editing system to implement two new strategies for BB resistance. Knock-in of TAL effector binding elements (EBE) derived from the BB susceptible gene SWEET14 into the promoter of a dysfunctional executor R gene xa23 reaches 47.2% with desired edits including biallelic editing at 18% in T0 generation that enables an inducible TALE-dependent BB resistance. Editing the transcription factor TFIIA gene TFIIAγ5 required for TAL effector-dependent BB susceptibility recapitulates the resistance of xa5 at an editing efficiency of 88.5% with biallelic editing rate of 30% in T0 generation. The engineered loci provided resistance against multiple Xoo strains in T1 generation. Whole-genome sequencing detected no OsMLH1dn-associated random mutations and no off-target editing demonstrating high specificity of this PE system. This is the first-ever report to use PE system to engineer resistance against biotic stress and to demonstrate knock-in of 30-nucleotides cis-regulatory element at high efficiency. The new strategies hold promises to fend rice off the evolving Xoo strains and protect it from epidemics.

Protein Modification Characteristics of the Malaria Parasite Plasmodium falciparum and the Infected Erythrocytes.

Malaria elimination is still pending on the development of novel tools that rely on a deep understanding of parasite biology. Proteins of all living cells undergo myriad posttranslational modifications (PTMs) that are critical to multifarious life processes. An extensive proteome-wide dissection revealed a fine PTM map of most proteins in both Plasmodium falciparum, the causative agent of severe malaria, and the infected red blood cells. More than two-thirds of proteins of the parasite and its host cell underwent extensive and dynamic modification throughout the erythrocytic developmental stage. PTMs critically modulate the virulence factors involved in the host-parasite interaction and pathogenesis. Furthermore, P. falciparum stabilized the supporting proteins of erythrocyte origin by selective demodification. Collectively, our multiple omic analyses, apart from having furthered a deep understanding of the systems biology of P. falciparum and malaria pathogenesis, provide a valuable resource for mining new antimalarial targets.

Polygalae Radix Oligosaccharide Esters May Relieve Depressive-like Behavior in Rats with Chronic Unpredictable Mild Stress via Modulation of Gut Microbiota.

Polygalae radix (PR) is a well-known traditional Chinese medicine that is used to treat depression, and polygalae radix oligosaccharide esters (PROEs) are the main active ingredient. Although gut microbiota are now believed to play key role in depression, the effects of PROEs on depression via modulation of gut microbiota remain unknown. In this article, we investigate the effect of PROEs on the gut microbiota of a depression rat and the possible mechanism responsible. The depression rat model was induced by solitary rearing combined with chronic unpredictable mild stress (CUMS). The depression-like behavior, the influence on the hypothalamic-pituitary-adrenal (HPA) axis, the contents of monoamine neurotransmitter in the hippocampus, and the quantity of short-chain fatty acids (SCFAs) in the feces were each assessed, and the serum levels of lipopolysaccharide (LPS) and interleukin-6 (IL-6) were measured by ELISA. Additionally, ultrastructural changes of the duodenal and colonic epithelium were observed under transmission electron microscope, and the gut microbiota were profiled by using 16S rRNA sequencing. The results show that PROEs alleviated the depression-like behavior of the depression model rats, increased the level of monoamine neurotransmitters in the brain, and reduced the hyperfunction of the HPA axis. Furthermore, PROEs regulated the imbalance of the gut microbiota in the rats, relieving intestinal mucosal damage by increasing the relative abundance of gut microbiota with intestinal barrier protective functions, and adjusting the level of SCFAs in the feces, as well as the serum levels of LPS and IL-6. Thus, we find that PROEs had an antidepressant effect through the restructuring of gut microbiota that restored the function of the intestinal barrier, reduced the release of intestinal endotoxin, and constrained the inflammatory response.

Tick populations and molecular detection of selected tick-borne pathogens in questing ticks from northern and central Tanzania.

Ticks are vectors and reservoirs of a variety of pathogens including protozoa, bacteria and viruses which cause tick-borne diseases (TBDs) in humans and livestock. TBDs pose serious constraints to the improvement of livestock production in tropical and subtropical regions of the world. Despite their wide distribution, information on the tick and pathogen relationship is scarce in Tanzania. We used nested PCR and sequencing to screen pathogens of public and veterinary health importance in ticks collected by flagging from four districts of Tanzania. In total, 2021 ticks comprising nine species were identified. DNA from ticks was pooled according to tick species, developmental stage, and location, then screened for Babesia bigemina, Babesia bovis, Theileria parva and Coxiella burnetii. Out of 377 pools, 34.7% were positive for at least one pathogen. Theileria parva was the most abundant with a minimum infection rate (MIR) of 2.8%, followed by B. bigemina (MIR = 1.8%) and B. bovis (MIR = 0.8%). Multiple pathogens detection was observed in 7.2% of the tested pools. However, PCR screening of individual tick DNA revealed that only 0.3% of the examined pools had co-infection. DNA of C. burnetii was never detected in any tick DNA pool. The MIR of tick-borne pathogens (TBPs) differed significantly among districts, seasons, tick species, and tick developmental stages. Sequence analysis showed that B. bigemina RAP-1a, B. bovis SBP-4, and T. parva p104 genes were conserved among pathogens in the four districts. Despite the absence of C. burnetii in ticks, considering its pathogenic potential, it is essential to continue monitoring for its possible recurrence in ticks. This information adds to the knowledge of TBPs epidemiology and will contribute to the scientific basis for planning future control strategies.

Analysis of Intestinal Metabolites in SR-B1 Knockout Mice via Ultra-Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry.

Scavenger receptor class B type 1 (SR-B1), a multiligand membrane receptor, is expressed in a gradient along the gastrocolic axis. SR-B1 deficiency enhances lymphocyte proliferation and elevates inflammatory cytokine production in macrophages. However, whether SR-B1 affects intestinal metabolites is unclear. In this study, we detected metabolite changes in the intestinal tissue of SR-B1-/- mice, including amino acids and neurotransmitters, by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) and HPLC. We found that SR-B1-/- mice exhibited changes in intestinal lipid metabolites and metabolic pathways, including the glycerophospholipid, sphingolipid, linoleic acid, taurine, and hypotaurine metabolic pathways. SR-B1 deficiency influenced the contents of amino acids and neurotransmitters in all parts of the intestine; the contents of leucine (LEU), phenylalanine (PHE), tryptophan (TRP), and tyrosine (TYR) were affected in all parts of the intestine; and the contents of 3,4-dihydroxyphenylacetic acid (DOPAC) and dopamine (DA) were significantly decreased in both the colon and rectum. In summary, SR-B1 deficiency regulated intestinal lipids, amino acids, and neurotransmitter metabolism in mice.

Optimized prime editing efficiently generates heritable mutations in maize.

Low efficiency is the main obstacle to using prime editing in maize (Zea mays). Recently, prime-editing efficiency was greatly improved in mammalian cells and rice (Oryza sativa) plants by engineering prime-editing guide RNAs (pegRNAs), optimizing the prime editor (PE) protein, and manipulating cellular determinants of prime editing. In this study, we tested PEs optimized via these three strategies in maize. We demonstrated that the ePE5max system, composed of PEmax, epegRNAs (pegRNA-evopreQ. 1), nicking single guide RNAs (sgRNAs), and MLH1dn, efficiently generated heritable mutations that conferred resistance to herbicides that inhibit 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), acetolactate synthase (ALS), or acetyl CoA carboxylase (ACCase) activity. Collectively, we demonstrate that the ePE5max system has sufficient efficiency to generate heritable (homozygous or heterozygous) mutations in maize target genes and that the main obstacle to using PEs in maize has thus been removed.

Novel Hepatic Schistosomula Antigens as Promising Targets for Immunodiagnosis and Immunoprotection of Schistosomiasis japonica.

BACKGROUND: Antigens of migrating schistosomula are promising candidates as schistosomiasis vaccine targets, since immune attack on hepatic schistosomula would interrupt the parasites life cycle and reduce egg burden on the host. METHODS: In this study, we report a collection of Schistosoma japonicum schistosomula proteins (SjScPs) that are highly expressed in hepatic schistosomula. The expression characteristics, antigenicity and immune protection of these proteins were studied by western blot, ELISA, immunofluorescence and challenge assays. RESULTS: We found that several of these SjScPs were highly antigenic and could effectively stimulate humoral immune responses in both human and other mammalian hosts. In particular, SjScP25, SjScP37, SjScP41, SjScP80, and SjScP88 showed high potential as biomarkers for schistosomiasis immunodiagnosis. Furthermore, we demonstrated that immunization with several of the recombinant SjScPs were able to protect mice from S japonicum challenge infection, with SjScP25 generating the most protective results. CONCLUSIONS: Our work represents a group of novel schistosome immunogens, which may be promising schistosomiasis japonica diagnosis and vaccine candidates.

Singular Configuration Analysis and Singularity Avoidance with Application in an Intelligent Robotic Manipulator.

Recently, robotic sensor systems have gained more attention annually in complex system sense strategies. The robotic sensors sense the information from itself and the environment, and fuse information for the use of perception, decision, planning, and control. As an important supplement to traditional industrial robots, co-bots (short for co-working robots) play an increasingly vital role in helping small and medium-sized enterprises realize intelligent manufacturing. They have high flexibility and safety so that they can assist humans to complete highly repetitive and high-precision work. In order to maintain robot safe operation in the increasing complex working environment and human-computer intelligent interactive control, this paper is concerned with the problem of applicant accuracy analysis and singularity avoidance for co-bots. Based on the dynamic model with load and torque sensors, which is used to detect the external force at the end of the robot, this paper systematically analyzes the causes of singularity phenomenon in the robot motion control. The inverse solution is obtained by analytical method and numerical method, respectively. In order to ensure the smooth and safe operation in the whole workspace, it is necessary for a robot to avoid singularity. Singularity avoidance schemes are utilized for different control tasks, including point-to-point control and continuous path control. Corresponding simulation experiments are designed to verify the effectiveness of different evasion schemes, in which the advantages and disadvantages are compared and analyzed.

Comparative transcriptome analysis of Chinese grass shrimp (Palaemonetes sinensis) hepatopancreas under ectoparasitic isopod (Tachaea chinensis) infection.

Tachaea chinensis, a parasitic isopod, negatively affects the production of several commercially important shrimp species. To better understand the interaction between shrimp immunity and isopod infection, we performed a transcriptome analysis of the hepatopancreas of Palaemonetes sinensis challenged with T. chinensis. After assembly and annotation, 75,980 high-quality unigenes were obtained using RNA-seq data. Differential gene expression analysis revealed 896 significantly differently expressed genes (DEGs) after infection, with 452 and 444 upregulated and downregulated genes, respectively. Specifically, expression levels of genes involved in detoxification, such as the interferon regulatory factor, venom carboxylesterase-6, serine proteinase inhibitor, and cytochrome P450, were upregulated. Furthermore, expression levels of genes corresponding to retinol dehydrogenase, triosephosphate isomerase, variant ionotropic glutamate receptor, and phosphoenolpyruvate carboxykinase were significantly upregulated after isopod parasitization, indicating that the shrimp's visual system was influenced by isopod parasitization. Moreover, quantitative real-time PCR of 10 DEGs helped validate the RNA-seq findings. These results provide a valuable basis for future studies on the elucidation of immune responses of P. sinensis to T. chinensis infection.

Determination of lumefantrine as an effective drug against Toxoplasma gondii infection - in vitro and in vivo study.

Toxoplasma gondii is an obligate intracellular protozoan parasite, which can infect almost all warm-blooded animals, including humans, leading to toxoplasmosis. Currently, the effective treatment for human toxoplasmosis is the combination of sulphadiazine and pyrimethamine. However, both drugs have serious side-effects and toxicity in the host. Therefore, there is an urgent need for the discovery of new anti-T. gondii drugs with high potency and less or no side-effects. Our findings suggest that lumefantrine exerts activity against T. gondii by inhibiting its proliferation in Vero cells in vitro without being toxic to Vero cells (P ≤ 0.01). Lumefantrine prolonged mice infected with T. gondii from death for 3 days at the concentration of 50 µg L-1 than negative control (phosphate-buffered saline treated only), and reduced the parasite burden in mouse tissues in vivo (P ≤ 0.01; P ≤ 0.05). In addition, a significant increase in interferon gamma (IFN-γ) production was observed in high-dose lumefantrine-treated mice (P ≤ 0.01), whereas interleukin 10 (IL-10) and IL-4 levels increased in low-dose lumefantrine-treated mice (P ≤ 0.01). The results demonstrated that lumefantrine may be a promising agent to treat toxoplasmosis, and more experiments on the protective mechanism of lumefantrine should be undertaken in further studies.

Global Lysine Crotonylation and 2-Hydroxyisobutyrylation in Phenotypically Different Toxoplasma gondii Parasites.

Toxoplasma gondii is a unicellular protozoan parasite of the phylum Apicomplexa. The parasite repeatedly goes through a cycle of invasion, division and induction of host cell rupture, which is an obligatory process for proliferation inside warm-blooded animals. It is known that the biology of the parasite is controlled by a variety of mechanisms ranging from genomic to epigenetic to transcriptional regulation. In this study, we investigated the global protein posttranslational lysine crotonylation and 2-hydroxyisobutyrylation of two T. gondii strains, RH and ME49, which represent distinct phenotypes for proliferation and pathogenicity in the host. Proteins with differential expression and modification patterns associated with parasite phenotypes were identified. Many proteins in T. gondii were crotonylated and 2-hydroxyisobutyrylated, and they were localized in diverse subcellular compartments involved in a wide variety of cellular functions such as motility, host invasion, metabolism and epigenetic gene regulation. These findings suggest that lysine crotonylation and 2-hydroxyisobutyrylation are ubiquitous throughout the T. gondii proteome, regulating critical functions of the modified proteins. These data provide a basis for identifying important proteins associated with parasite development and pathogenicity.

Life cycle of the ectoparasite Tachaea chinensis (Isopoda: Corallanidae) on the freshwater shrimp Palaemonetes sinensis (Decapoda: Palaemonidae).

In this study, we describe in detail the life cycle of Tachaea chinensis (Isopoda: Corallanidae), a branchial ectoparasitic isopod that infests the freshwater shrimp Palaemonetes sinensis in China. We obtained 14 ovigerous T. chinensis females (8.22-11.92 mm in length) and observed the development of embryos through 5 sequential ontogenetic stages within the brood pouches (marsupium) of these females. The number of eggs or mancae (post-larval juveniles) held in the female marsupium ranged from 31 to 86, with a mean ± SD of 61.25 ± 16.16 eggs. Female T. chinensis were semelparous, i.e. individuals died following the release of mancae from the marsupium. Released mancae were non-planktonic and immediately infective to host shrimps. However, only a few mancae successfully established contact with a host, and it is thus assumed that the remainder were predated by shrimp. Attached T. chinensis fed on the host hemolymph, and subsequent to host death, these isopods typically searched for a new host. We also found that T. chinensis exhibits a host preference: most mancae attached to P. sinensis rather than to Neocaridina sp. or Macrobrachium nipponense. This study provides valuable empirical data that will support future research on the prevention and control of parasitic isopod infections.

Comprehensive quality evaluation of Polygoni Orientalis Fructus and its processed product: chemical fingerprinting and simultaneous determination of seven major components coupled with chemometric analyses.

INTRODUCTION: Polygoni Orientalis Fructus (POF) is a clinically effective Chinese medicine. Raw POF (RPOF) and POF Tostus (POFT) are used separately in clinics. However, incomplete progress has been made on quality control. OBJECTIVE: To establish a comprehensive method for quality assessment of RPOF and POFT and to discriminate these two varieties. METHODOLOGY: High-performance liquid chromatography combined with the diode array detector (HPLC-DAD) methods were developed for fingerprinting and quantitative analysis of seven major compounds in RPOF and POFT, and the main components were determined by HPLC-DAD coupled with Fourier-transform ion cyclotron resonance-mass spectrometry. Chemometric approaches were performed to discriminate RPOF and POFT and to screen discriminatory components. RESULTS: Fingerprints were established and 12 common peaks were identified, cannabisin G and cannabisin E were firstly identified from POF. In quantitative analysis, all analytes showed good regression (R > 0.9996) within test ranges and the recovery of the method was in the range 96.6-104.3%. Fingerprints in conjunction with similarity analysis and hierarchical clustering analysis (HCA) demonstrated the consistent quality of RPOF and showed a clear discrimination between RPOF and POFT. Principal component analysis, partial least-squares discriminant analysis, and heatmap-HCA on quantitative data not only gave a clear differentiation between RPOF and POFT, but they also suggested that quercetin, 3,5,7-trihydroxychromone, and N-trans-feruloyltyramine acted as the main factors responsible for the sample differences. CONCLUSIONS: Chromatographic analysis in combination with chemometric analysis provides a simple and reliable method of comparing and evaluating the qualities of RPOF and POFT.

A Sialic Acid-Binding Protein SABP1 of Toxoplasma gondii Mediates Host Cell Attachment and Invasion.

Many obligate intracellular apicomplexan parasites have adapted a distinct invasion mechanism involving a close interaction between the parasite ligands and the sialic acid (SA) receptor. We found that sialic acid binding protein-1 (SABP1), localized on the outer membrane of the zoonotic parasite Toxoplasma gondii, readily binds to sialic acid on the host cell surface. The binding was sensitive to neuraminidase treatment. Cells preincubated with recombinant SABP1 protein resisted parasite invasion in vitro. The parasite lost its invasion capacity and animal infectivity after the SABP1 gene was deleted, whereas complementation of the SABP1 gene restored the virulence of the knockout strain. These data establish the critical role of SABP1 in the invasion process of T. gondii. The previously uncharacterized protein, SABP1, facilitated T. gondii attachment and invasion via sialic acid receptors.

A Novel Ternary Vector System United with Morphogenic Genes Enhances CRISPR/Cas Delivery in Maize.

The lack of efficient delivery methods is a major barrier to clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas)-mediated genome editing in many plant species. Combinations of morphogenic regulator (MR) genes and ternary vector systems are promising solutions to this problem. In this study, we first demonstrated that MR vectors greatly enhance maize (Zea mays) transformation. We then tested a CRISPR/Cas9 MR vector in maize and found that the MR and CRISPR/Cas9 modules have no negative influence on each other. Finally, we developed a novel ternary vector system to integrate the MR and CRISPR/Cas modules. Our ternary vector system is composed of new pGreen-like binary vectors, here named pGreen3, and a pVS1-based virulence helper plasmid, which also functions as a replication helper for the pGreen3 vectors in Agrobacterium tumefaciens The pGreen3 vectors were derived from the plasmid pRK2 and display advantages over pGreen2 vectors regarding both compatibility and stability. We demonstrated that the union of our ternary vector system with MR gene modules has additive effects in enhancing maize transformation and that this enhancement is especially evident in the transformation of recalcitrant maize inbred lines. Collectively, our ternary vector system-based tools provide a user-friendly solution to the low efficiency of CRISPR/Cas delivery in maize and represent a basic platform for developing efficient delivery tools to use in other plant species recalcitrant to transformation.

Antioxidant and immune responses of the Oriental river prawn Macrobrachium nipponense to the isopod parasite Tachaea chinensis.

Tachaea chinensis is a parasitic isopod that negatively affects the production of several commercially important shrimp species in China. To date, there have been no reports on the antioxidant and immune responses of host shrimps to isopod parasite infection or their underlying molecular mechanisms. In this study, we examined the specific activities of the immune and antioxidant enzymes of the shrimp Macrobrachium nipponense during the course of a 15-day isopod infection and evaluated expression of related genes. Acid phosphatase (ACP) and alkaline phosphatase (AKP) activities and malondialdehyde (MDA) levels showed significant peaks over 15 days of exposure in both the hepatopancreas and muscle (P < 0.05), whereas catalase (CAT) activity increased continuously during infection (P < 0.05), and lysozyme (LZM) activity increased only in the hepatopancreas (P < 0.05). After 6 days of exposure, expressions of glutathione S-transferase (GST), ACP, and AKP were significantly higher than at 12 days. Compared with the control group, at 12 days, S-(hydroxymethyl) glutathione dehydrogenase activity and glutathione metabolism pathways were significantly inhibited (P < 0.05). Furthermore, the NOD-like receptor signaling pathway and antigen processing and presentation pathways were also significantly inhibited at 12 days compared with that at 6 days (P < 0.05), indicating that T. chinensis parasitism could perturb the antioxidant and immune systems of shrimp hosts during the latter stages of infection. Additionally, the molting and mortality rates of M. nipponense increased the duration of parasitism. These findings indicate that M. nipponense can activate antioxidant and immune defense systems during the early period during isopod parasitism, whereas the parasite can negatively affect these host defense systems during the latter period. Our findings accordingly provide valuable insights into the antioxidant defense systems and immune function characterizing parasite-host interactions.

Metabolic responses of shrimp Palaemonetes sinensis to isopod Tachaea chinensis parasitization.

Tachaea chinensis, a parasitic isopod, negatively affects the production of several commercially important shrimp species in China. The mechanism of parasite-host interaction cannot be accurately described by transcriptomic and proteomic approaches individually. Here, comparative metabolite profiling was used to achieve a broad coverage of primary metabolite changes in Chinese grass shrimp Palaemonetes sinensis following T. chinensis parasitization. In total, 66 metabolites were significantly differentially accumulated between the control and infected groups; of these, 19 were upregulated and 47 were downregulated after T. chinensis infection. Moreover, the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed that 10 pathways were significantly enriched. The protein digestion and absorption pathways were highly enriched, followed by the mineral absorption, aminoacyl-tRNA biosynthesis, biosynthesis of amino acids, and metabolic metabolism pathways. Parasitization by T. chinensis enhanced the glycolytic pathway and tricarboxylic acid (TCA) cycle in P. sinensis, thereby releasing more energy for swimming, foraging, and evading predation. Glucogenic amino acids such as alanine, histidine, glutamine, and proline were consumed to generate glutamate and enhance the TCA cycle. Nucleotide-related metabolic pathways were downregulated, possibly because T. chinensis can secrete molecules to degrade nucleotides and inhibit hemostasis and inflammatory responses. These results suggest that the isopod parasite can increase the host's metabolic burden by enhancing the host's TCA cycle and secreting molecules to degrade host proteins, thereby enabling the parasite to feed on the host and inhibit an inflammatory response. The results will be a valuable contribution to understanding the metabolic responses of crustaceans to isopod parasitism.