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Carbohydrates are widely distributed in nature as an important nutritional substance and energy source. However, the utilization efficiency of carbohydrates is very poor in fish. Over consumption of carbohydrates will cause excessive inflammatory response and result in lower pathogen resistance in fish. Probiotics have been widely used to prevent inflammation, but the underlying mechanism still needs more exploration. In this study, three diets, including a control diet (CD), a high-carbohydrate diet (HD) and the HD supplemented with Bacillus amyloliquefaciens SS1 (HDB) were used to feed Nile tilapia for 10 weeks. At the end of the feeding trial, fish were challenged with Aeromonas hydrophila (A. hydrophila) for 7 days. The data showed that the addition of Bacillus amyloliquefaciens SS1 (B. amyloliquefaciens SS1) significantly increased the survival rate and enhanced the respiratory burst activity of head kidney leukocytes in Nile tilapia. B. amyloliquefaciens SS1 treatment significantly elevated the anti-oxidative capability, which was evidenced by higher activities of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC), and higher content of reduced glutathione (GSH) in the serum. Administration with B. amyloliquefaciens SS1 effectively suppressed inflammatory response in the liver by inhibiting nuclear factor kappa-B (NF-κB)/interleukin-1 beta (IL-1β) inflammatory signaling pathway. In vitro analysis suggested that intestinal bacteria derived-acetate has the antioxidant capability, which may account for the alleviation of inflammation. Overall, this study demonstrated that dietary supplementation with B. amyloliquefaciens SS1 protected Nile Tilapia against A. hydrophila infection and suppressed liver inflammation by enhancing antioxidant capability.

Sesarmops sinensis is a dominant omnivorous crab species, which plays an important ecological function in salt marsh ecosystems. To better understand its immune system and immune related genes under pathogen infection, the transcriptome was analyzed by comparing the data of S. sinensis hepatopancreas stimulated by PBS and PGN. A set of assembly and annotation identified 39,039 unigenes with an average length of 1105 bp, obtaining 1300 differentially expressed genes (DEGs) in all, which included 466 remarkably up-regulated unigenes and 834 remarkably down-regulated unigenes. In addition, based on mensurable real time-polymerase chain reaction and high-throughput sequencing, several immune responsive genes were found to be markedly up-regulated under PGN stimulation. In conclusion, in addition to enriching the existing transcriptome data of S. sinensis, this study also clarified the immune response of S. sinensis to PGN stimulation, which will help us to further understand the crustacean's immune system.

Some of the gas turbine components are exposed to high temperature corrosion. Therefore, the life cycle of gas turbine is directly affected by the durability of the components. The blades of the gas turbine are protected by film cooling holes under the condition of combining with thermal barrier coating (TBC) system. The TBC systems improve durability of the high temperature components under the condition of increasing the operating temperature. In order to improve the durability of TBC system, simulation and optimization methods were studied in this paper. Firstly, discussed a theoretical model under the thermal and mechanical loading conditions. In the following step, the hole deformations with the various thermo-mechanical conditions induced by high temperature environment and centripetal force due to rotation of the blade were optimized by design of experiments (DOE) method, in order to improve the durability of TBC system. Next, the deformations subjected to thermo-mechanical cycling induced by high temperature environment and vibration due to real operating condition were discussed. The results show that the effect of vibration is not significant compared to the effect of the centripetal force. Keywords: Thermally grown oxide, Gas turbine blade, Vibration, Optimization

Flesh quality is influenced by diet components, but the underlying mechanism remains unclear. This study aimed to investigate the effect of replacing soybean meal (SBM) protein with cottonseed protein concentrate (CPC) at different levels (0%, CK; 15%, CPC15; 30%, CPC30 and 45%, CPC45) on the flesh quality of Nile tilapia. The results indicated that different protein sources influenced muscle amino acid composition instead of fatty acid composition. Lower muscle lipid content was found in CPC45, which in turn significantly altered the muscle texture. The hepatic lipid metabolism-related genes were detected and we found that CPC45 significantly suppressed the lipogenesis and promoted lipolysis. Higher content of microbiota-derived butyrate was found in the intestinal content of CPC45 and butyrate could decrease the lipid accumulation in vitro. Replacing SBM with CPC increased the intestinal butyrate to suppress the lipogenesis in the liver which may account for the increased muscle hardness.

To optimize the spatial distribution of cotton bolls and to increase the yield, the relationship between yield components and boll spatial distribution was investigated among different Bt (Bacillus thuringensis) cotton varieties. A five-year field experiment was conducted to reveal the reasons for the differences in lint yield and fiber quality across three Bt cotton varieties with different yield formations from 2013 to 2017. The lint yield of Jiman 169 (the average yield from 2013–2017 was 42.2 g/plant) was the highest, i.e., 16.3 and 36.9% higher than Lumianyan 21 (L21) and Daizimian 99B (99B), respectively. And the differences in boll weight among the three cultivars were similar to the lint yield, while the others yield components were not. So the increase in lint yield was mainly attributed to the enlargement in boll weight. However, the change in fiber quality was inconsistent with the lint yield, and the quality of L21 was significantly better than that of Jimian 169 (J169) and 99B, which was caused by the diversity of boll spatial distribution. Compared with 99B, the loose-type J169 had the highest number of large bolls in inner positions; the tight-type L21 had a few large bolls and the highest number of lower and middle bolls. And approximately 80.72% of the lint yield was concentrated on the inner nodes in Jiman 169, compared with 77.44% of L21 and 66.73% of 99B during the five-year experiment. Although lint yield was significantly affected by the interannual changes, the lint yield of J169 was the highest and the most stable, as well as its yield components. These observations demonstrated the increase in lint yield was due to the increase in boll weight, and the large bolls and high fiber quality were attributed to the optimal distribution of bolls within the canopies.

Peroxisome proliferator-activated receptor α (PPARα) plays critical physiological roles in energy metabolism, antioxidation and immunity of mammals, however, these functions have not been fully understood in fish. In the present study, Nile tilapia (Oreochromis niloticus) were fed with fenofibrate, an agonist of PPARα, for six weeks, and subsequently challenged with Aeromonas hydrophila. The results showed that PPARα was efficiently activated by fenofibrate through increasing mRNA and protein expressions and protein dephosphorylation. PPARα activation increased significantly mitochondrial fatty acid β-oxidation efficiency, the copy number of mitochondrial DNA and expression of monoamine oxidase (MAO), a marker gene of mitochondria. Meanwhile, PPARα activation also increased significantly the expression of NADH dehydrogenase [ubiquinone] 1α subcomplex subunit 9 (NDUFA9, complex I) and mitochondrial cytochrome c oxidase 1 (MTCO1, complex IV). The fenofibrate-fed fish had higher survival rate when exposed to A. hydrophila. Moreover, the fenofibrate-fed fish also had higher activities of immune and antioxidative enzymes, and gene expressions of anti-inflammatory cytokines, while had lower expressions of pro-inflammatory cytokine genes. Taken together, PPARα activation improved the ability of Nile tilapia to resist A. hydrophila, mainly through enhancing mitochondrial fatty acids β-oxidation, immune and antioxidant capacities, as well as inhibiting inflammation. This is the first study showing the regulatory effects of PPARα activation on immune functions through increasing mitochondria-mediated energy supply in fish.

Cold stress is a major threat to fish in both nature and aquaculture, and can induce oxidative stress in various fish. While the exact role of oxidative stress in cold-caused mortality is still unknown. The purpose of the present study was to evaluate the effects of oxidative stress on cold tolerance in fish and verify whether changing oxidative status could affect cold tolerance. We firstly demonstrated that acute cold exposure induced high oxidative stress in zebrafish liver, which may lead to mortality. Then we performed in vivo and in vitro experiments to determine the effects of the altered oxidative status on cold tolerance in zebrafish and zebrafish liver cell line (ZFL), respectively. In the in vivo study, the zebrafish which were fed with α-lipoic acid or reduced glutathione had lower cold-caused oxidative stress and tissues damage, and showed higher cold tolerance. In the experiment using zebrafish cells, increasing oxidative stress by H2O2 decreased the cellular cold tolerance, and the cold tolerance was partly recovered when oxidative stress was reduced by the addition of Vitamin C (VC). Taken together, we conclude that the reduction of oxidative stress increases cold tolerance in fish.

Three new lignanamides, melongenamide E–G (1–3), together with fourteen known analogues (4-17) were isolated by bioassay-guided fractionation from the roots of Solanum melongena L. The chemical structures of all isolated compounds were elucidated using 1D and 2D NMR experiments and by comparing their spectroscopic and physical data with values from the published literature. These isolated compounds were tested for their inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in a macrophage cell line RAW 264.7. Compounds 1–7 and 10 showed moderate inhibition of NO production with IC50 values ranging from 10.6 ± 2.3 to 33.7 ± 2.7 μM.

The wide use of high-fat diet (HFD) causes negative effects on flesh quality in farmed fish. l-carnitine, a lipid-lowering additive, enhances mitochondrial fatty acid β-oxidation. However its roles in alleviating the effects of HFD on flesh quality in fish are unknown. We fed Nile tilapia with medium-fat diet (MFD, 6% dietary lipid), high-fat diet (HFD, 12% dietary lipid) and HFCD supplemented with l-carnitine (HFCD + 400 mg/kg l-carnitine) for 10 weeks. The HFD-fed fish had higher fat deposition, pH value, myofiber density and flesh hardness than those fed on MFD. However, feeding the fish with the HFCD improved lipid catabolism, which increased significantly lactic acid content and myofiber diameter in muscle, thus reduced pH and hardness values. HFCD also reduced endoplasmic reticulum stress and myofiber apoptosis caused by HFD in the fish. Our study suggests that dietary l-carnitine supplementation alleviates the negative effects of HFD on flesh quality of farmed fish.

Animal growth performance is determined by food intake, digestion and nutrient absorption and the complex central and peripheral nerves may regulate the quantity of food intake. This study evaluates the effects of gamma-aminobutyric acid (GABA) supplements in purified diets on the growth performance, food intake and digestive ability of juvenile Chinese mitten crab Eriocheir sinensis, and the possible mechanism of neuromodulation. A total of 1200 juvenile crabs (0.77 ± 0.02 g) were fed with six diets supplemented with graded GABA levels (0, 40, 80, 160, 320 and 640 mg/kg dry matter) for 8 weeks. Each diet group had five replicates, and each replicate had 40 crabs in a tank (100 × 80 × 60 cm). The weight gain, specific growth rate, molting frequency, and the activities of digestion (α-amylase, trypsin and lipase) and absorption (Na+-K+-ATPase and γ- glutamyl transferase) enzymes were significantly increased by moderate dietary GABA supplementation compared with the 0 mg/kg GABA supplementation group. Furthermore, the food intake of juvenile E. sinensis was significantly increased with moderate dietary GABA supplementation compared with the 0 mg/kg GABA supplementation group. The qRT-PCR results showed that the expression of the orexigenic neural signal-related genes was significantly up-regulated, and the anorexigenic neural signal-related genes were significantly down-regulated in the cranial ganglia, thoracic ganglia and intestine tissues. Meanwhile, the expressions of the main genes involved in taste modulation and reward regulation were significantly up-regulated, whereas the expression of genes related to punishment regulation was significantly down-regulated in cranial ganglia and thoracic ganglia. Two-slope broken-line regression analysis of specific growth rate and weight gain against the dietary GABA levels showed that dietary GABA at the optimal dietary level was 84–89 mg/kg, and this level can improve growth performance, food intake, digestion and absorption in juvenile E. sinensis. GABA might act as an orexigenic neural signal or work with other appetite-related nerve signals to promote food intake by participating in regulating the satiety circuit and the reward circuit.

Dietary usage of microencapsulated oils has been proved to promote growth and gut health in land animals, however, these beneficial effects have not been intensively investigated in aquatic animals. The present study hypothesized that dietary microencapsulated oils could alleviate negative effects caused by high-fat diet (HFD) in fish, thus we fed juvenile Nile tilapia with HFD (15% fat) by using normal or microencapsulated oils as lipid sources for 8 weeks. To compare the effects between different microencapsulated oils with different fatty acid composition, two oil mixtures (PL: 60% palm oil +40% linseed oil; FL: 60% fish oil +40% linseed oil) were used. After feeding trial, the growth, body composition, fatty acid composition, resistance to pathogenic bacteria challenge, activities of immune enzymes, expressions of inflammation genes, intestinal structure and microbiota were measured, respectively. The results indicated that microencapsulated oils didn’t affect fish growth, body composition, and muscle fatty acid composition, but improved the intestinal activities of lysozyme (LZM) and resistance against Aeromonas hydrophila. Further tests showed that microencapsulated oils not only improved the structure of intestine, but also increased the number of beneficial bacteria (Bacillus and Paenibacillus) and decreased the number of harmful bacteria (Pseudoalteromonas and Roseovarius) in the intestine. Those beneficial effects are more significant between normal PL oil and microencapsulated PL oil, but no significant difference in FL oil groups. Taken together, these results suggested that microencapsulated oil might enhance immune activities in the Nile tilapia fed with HFD by improving intestinal structure and microflora. Moreover, the beneficial effects of the microencapsulated oil are correlated to the oil composition. To the best of our knowledge, this is the first study illustrating the beneficial effects of dietary microencapsulated oil in the fish fed with HFD.

Two new flavonoid–triterpene saponin meroterpenoids, clinoposides G (1) and H (2) were isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze. Their structures were elucidated through spectroscopic and electronic circular dichroism (ECD) analyses. Compounds 1 and 2 were evaluated for their protective effects against anoxia/reoxygenation(A/R)-induced injury in H9c2 cells. A/R treatment severely injured the H9c2 cells, which was accompanied by apoptosis. Both 1 and 2 pretreatment significantly inhibited cell injury and apoptosis, improved mitochondrial membrane potential, increased activities of antioxidant enzymes, and reduced the levels of the inflammatory cytokines. In addition, the presence of 1 and 2 significantly decreased the protein level of p65 and increased the level of Nrf2 in cell nucleus. Unique chemical structure and good biological activity of 1 and 2 elucidated the potential of meroterpenoids as a promising reagent for treating heart disease.

Background: Antibiotics used globally to treat human and animal diseases exist ubiquitously in the environment at low doses because of misuse, overdose and poor absorption after ingestion, coupled with their high-water solubility and degradation resistance. However, the systemic chronic effects of exposure to low environmental concentrations of antibiotics (LECAs) and legal aquaculture doses of antibiotics (LADAs) in fish and their human health risk are currently unknown. Objective: To investigate the in vivo chronic effects of exposure to LECAs and LADAs using oxytetracycline (OTC) and sulfamethoxazole (SMZ) in Nile tilapia (Oreochromis niloticus) and their human health risk. Methods: Twenty O. niloticus weighing 27.73 ± 0.81 g were exposed to water containing LECAs (OTC at 420 ng/L and SMZ at 260 ng/L) and diets supplemented with LADAs (OTC 80 mg/kg/day and SMZ 100 mg/kg/day) for twelve weeks. General physiological functions, metabolic activities, intestinal and hepatic health were systemically evaluated. The possible human health risks of the consumption of the experimental Nile tilapia fillets in adults and children were assessed by using risk quotient. Results: After exposure, we observed retarded growth performance accompanied by reduced nutrients digestibility, feed efficiency, organ indices, and lipid body composition in treated fish. Antibiotics distorted intestinal morphological features subsequently induced microbiota dysbiosis and suppressed intestinal tight junction proteins. Exposure of fish to LECAs and LADAs induced oxidative stress, suppressed innate immunity, stimulated inflammatory and detoxification responses, concomitantly inhibited antioxidant capacity and caused lipid peroxidation in intestine and liver organs. Both LECAs and LADAs enhanced gluconeogenesis, inhibited lipogenesis and fatty acid beta oxidation in intestine and liver organs. The exposure of fish to LECAs and LADAs induced anaerobic glycolytic pathway and affected intestinal fat catabolism in intestine while halted aerobic glycolysis, increased hepatic fat catabolism, and induced DNA damage in liver. The hazard risk quotient in children for fish treated with OTCD was >1 indicating human health risk. Conclusion: Overall, both LECAs and LADAs impair general physiological functions, nutritional metabolism, and compromise fish immune system. Consumption of fish fed with legal OTC provokes health risk in children. Global stringent prohibition policy for use of antibiotics in aquaculture production and strategies to limit their release into the environment are urgently required to protect human health. Keywords: Low environmental antibiotics, Legal aquaculture antibiotics, Toxicological effects, Human health risk

Antibiotics have been widely used in human and veterinary medicine to both treat and prevent disease. Due to their high water solubility and low bioavailability, many antibiotic residues have been found in aquatic environments. Fish are an indispensable link between the environmental pollution and human health. However, the chronic effects of environmental concentrations of antibiotics in fish have not been thoroughly investigated. Sulfamethoxazole (SMX) and oxytetracycline (OTC) are frequently detected in aquatic environments. In this study, zebrafish were exposed to SMX (260 ng/L) and OTC (420 ng/L) for a six-week period. Results indicated that exposure to antibiotics did not influence weight gain of fish but increased the metabolic rate and caused higher mortality when treated fish were challenged with Aeromonas hydrophila. Furthermore, exposure to antibiotics in water resulted in a significant decrease in intestinal goblet cell numbers, alkaline phosphatase (AKP), acid phosphatase (ACP) activities, and the anti-oxidant response while there was a significant increase in expression of inflammatory factors. Antibiotic exposure also disturbed the intestinal microbiota in the OTC-exposed group. Our results indicated that environmental antibiotic concentrations can impair the gut health of zebrafish. The potential health risk of antibiotic residues in water should be evaluated in the future.

Long-term feeding of fish with a high-fat diet (HFD) causes excess fat deposition and an impairment of immune function. In the present study, we aimed to determine whether dietary tea polyphenols (TPs) would ameliorate the adverse effects of HFD-feeding in GIFT tilapia. Juvenile GIFT tilapias (5.4 ± 0.9 g) were raised in twelve 200-L tanks (three tanks per diet, 20 fish per tank) and fed a control diet (6% fat, 36% protein), an HFD (12% fat, 36% protein), or an HFD supplemented with 50 mg/kg or 200 mg/kg TP for 8 weeks. The fish were hand-fed 5% of their body weight per day in three feeds, and maintained at 28 ± 1 °C under a 14-h light/10-h dark cycle. The fish in each tank were bulk weighed and counted fortnightly, and the daily feed amount was adjusted accordingly. At the end of the trial, the cumulative survival rate was calculated, and the weight gain and feed conversion ratio were calculated according to the bulk weight of fish in each tank. Tissues were collected from nine fish per diet, their organs were weighed, and biochemical and molecular indices were subsequently measured. HFD-feeding significantly increased lipid deposition, reduced cumulative survival from 96% to 75%, reduced hepatic alkaline phosphate activity (AKP) and serum total antioxidant capacity (T-AOC); and reduced the hepatic expression of immunoglobulin M (IgM), transforming growth factor-beta (TGF-β) and glutathione-S-transferase (GST) genes versus the control diet. The addition of TPs at 50 or 200 mg/kg both ameliorated the HFD-induced increase in lipid droplets in the liver (50 mg/kg TP from 40.83% to 17.27%; 200 mg/kg TP to 25.33%), and increased the cumulative survival rate of the tilapia. The addition of 50 mg/kg TP had a marked effect increasing cumulative survival to 90%, and increasing the activities of serum acid phosphatase (ACP), T-AOC; and IgM, TGF-β, nuclear factor-κB (NF-κB), superoxide dismutase (SOD), and GST gene expression to the highest level of the HFD-fed groups. The 50 mg/kg TP-containing diet also significantly increased the hepatic expression of carnitine palmitoyltransferase 1 alpha (CPT1α) versus the control diet. In contrast, the tilapia fed an HFD supplemented with 200 mg/kg TPs had the lowest expression of adipose triglyceride lipase, hormone-sensitive lipase, CPT1α, fatty acid synthase and acetyl-CoA carboxylase alpha genes of any of the groups, which implies that the lower and higher levels of TP supplementation have differing effects on lipid metabolism. The 200 mg/kg supplement had lower cumulative survival rate (82%), and smaller effects on serum ACP and hepatic AKP activities than the 50 mg/kg dose, and had no significant effect on serum T-AOC or the expression of IgM, TGF-β, GST, or NF-κB genes in the tilapia. These results indicate that the beneficial effects of TPs on the lipid metabolism and health of fish fed an HFD are dose-related. Moreover, they are likely to be largely mediated through lipid catabolism.

Dietary contamination of aflatoxin is commonly detected in aquafeeds, and its adverse effects on growth and health of farmed fish have been frequently reported. However, the effects of dietary aflatoxin on flesh quality in fish has not been well demonstrated. To evaluate these effects, in the present study, 360 yellow catfish (25 g ± 0.05 g) were randomly divided into three groups and fed with the diets containing different concentration of aflatoxin B1(AFB1) (Control diet; AFB44 diet: 44 μg/kg; AFB234 diet: 234 μg/kg) for 8 weeks. The results showed that the dietary AFB1 exposure didn’t significantly change fish growth, organ weights, fatty acid and amino acid composition, and AFB1 residues in muscle. However, the dietary AFB1 exposure with 234 μg/kg significantly increased the total lipid and triglycerides (TG) contents in muscle, while decreased flesh contents of moisture, total protein and phospholipids (PL), and reduced myofiber diameter. Moreover, the reduced myofiber number and increased connective tissue ratio were observed in the both AFB groups. The expressions of the genes related to myofibers structural proteins were reduced with the increase of dietary AFB1 concentration. Taken together, the present results demonstrated that the 8-week dietary exposure of AFB1 with 44 or 234 μg/kg in yellow catfish would not inhibit growth or cause high AFB1 residues in flesh, but could reduce the protein content and PL/TG ratio in flesh, and significantly change the characteristics of myofibers, thereby impaired the nutritional value, flavor and sensory quality of fish flesh.

This study investigates the effect of arginine (Arg) on the growth, antioxidant capacity, inflammation and immunity of juvenile Chinese mitten crab Eriocheir sinensis under high pH stress. Three diets containing 23.7 g/kg (control) 31.4 g/kg and 40.1 g/kg Arg were formulated and fed to crabs (3.37 ± 0.01 g) at high pH (pH = 9.5) for eight weeks. The weight gain and specific growth rate significantly increased in crabs fed the 31.4 g/kg and 40.1 g/kg Arg diets (P < 0.05). Furthermore, Arg improved the antioxidant capacity by increasing the activities of superoxide dismutase, catalase and glutathione production in the hepatopancreas (P < 0.05). In addition, Arg significantly downregulated the inflammatory and apoptotic genes including LPS-induced TNF-α factor, p38 mitogen-activated protein kinase, a disintegrin and metalloprotease 17, Bcl-2-associated X and cysteine-aspartic acid protease 3 (P < 0.05). Arg significantly upregulated the immune genes including crustin, relish and peroxinectin (P < 0.05). The respiratory burst of crabs fed the control diet was significantly lower than those fed the 31.4 g/kg Arg and 40.1 g/kg Arg diets after LPS injection of 0 h, 6 h and 12 h (P < 0.05). This study indicates that dietary Arg can alleviate oxidative stress and inflammation and improve the immunity of juvenile Chinese mitten crab under high pH stress.

Chronic hypoxia is a common environmental stress factor in aquaculture. Many researchers have illustrated the physiological and metabolic changes under chronic hypoxia, but there are few studies to evaluate the relationship between dietary nutrients and hypoxic adaptation in fish. In the present study, we fed zebrafish with control diet (C), high-carbohydrate diet (HC), high-fat diet (HF) and high-protein diet (HP) at normal dissolved oxygen (DO = 7.0 ± 0.5 mg/L) or low dissolved oxygen (DO = 2.5 ± 0.5 mg/L) environment, respectively. After a 7-week feeding trial, the growth performance, body composition, tissue biochemical indexes, mRNA expressions of hifα isoforms and nutrient metabolism-related genes, intestinal digestive enzyme activities and microbiota composition were measured. The results indicated that only the HP diet could alleviate the reduction of body weight and feed efficiency induced by chronic hypoxia, but the HF diet feeding worsened the adverse effects of chronic hypoxia in zebrafish. At the C groups, hypoxia increased catabolism of lipid and protein, but at the HP groups, hypoxia enhanced utilization of glycogen and protein. Compared to the C-hypoxia group, the HP feeding could activate transcription of hif-1a and its downstream glycolysis genes in chronic hypoxia. Furthermore, at hypoxic state, the HP feeding could alleviate the reduction of intestinal digestive enzyme activities and microbiota dysbiosis induced by the chronic hypoxia, including increasing bacterial diversity and decreasing Cetobacterium genus abundance. This is the first study indicating that high protein intake could strengthen ability of fish in resisting the negative effect of chronic hypoxia.

Fish are poor users of dietary carbohydrates and often display prolonged hyperglycemia and fat deposition after feeding high digestible carbohydrate diets. Recently, fatty acid β-oxidation (FAO) inhibition has been reported to increase glucose oxidation in fish. Therefore, this study tested the assumption that the inhibition of FAO with mildronate (MD, a carnitine synthesis inhibitor) might also increase glucose utilization and alleviate adverse effects induced by high starch diet (HSD) in Nile tilapia, Oreochromis niloticus. Nile tilapia juveniles (6.13 ± 0.11 g) were cultured in nine 200-L tanks (30 fish per tank) and divided into three groups (three tanks per group). The fish were fed twice a day (9:00 and 18:30) at 4% body weight by using a normal starch diet (NSD, 30% corn starch), a HSD (45% corn starch), or a HSD supplemented with MD (25 g/kg of diet, HSD + MD) for eight weeks. These three feeds contained approximately 35.8% protein and 6.4% lipid. The fish each tank were weighed every two weeks, and the feeding amount was adjusted accordingly. After the feeding trial, the fish fed on HSD showed higher hepatosomatic index (HSI), visceral somatic index (VSI), serum triglyceride concentration and whole-body and tissue (liver and muscle) lipid contents than those fed on NSD. The fish fed on HSD also had higher relative area of vacuolation in the liver, hepatic malondialdehyde (MDA) content, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in the serum than those fed on NSD. Moreover, the fish fed on HSD increased serum glucose and insulin concentrations, and hepatic lactate, pyruvate and glycogen contents, but reduced whole-body protein content and dietary protein utilization than those fed on NSD, indicating that HSD induced fat deposition, liver damage, glucose intolerance and lowered protein-sparing effect. However, the fish fed on HSD + MD decreased hepatic carnitine content and FAO activity, attenuated the indexes related to fat deposition and liver damage, improved blood glucose clearance and whole-body protein deposition than those fed on HSD, suggesting that the adverse effects caused by HSD were reversed after FAO inhibition. Furthermore, the fish fed on HSD down-regulated the expression of genes associated with glucose uptake, glycolysis, FAO process, and lipolysis compared to those fed on HSD + MD and NSD, yet up-regulated lipogenic and proteolytic genes. These data suggested that inhibition of FAO improved glucose utilization and alleviated the HSD-induced adverse effects in Nile tilapia. This work demonstrates that, modifying mitochondrial FAO activity regulates the ability of fish to adapt to HSD intake through remodeling energy homeostasis. Our study provides new insights into improving carbohydrate utilization in aquatic animals.

This study was to evaluate the relationship between myo-inositol synthesis and carbohydrate metabolism in Mozambique tilapia (Oreochromis mossambicus). Fish were immediately transferred from 0 psu (practical salinity units, the control) to 20 psu for 96 h with 60 fish in each group. Compared with the control group, the volume of the mitochondria-rich cell in the gills of O. mossambicus was significantly increased by acute hypersaline stress. The osmotic pressure and the contents of Na+, K+ and Cl− in the serum were significantly increased in the 20 psu group. Moreover, fish in the 20 psu group had significantly higher activities of glutathione peroxidase and superoxide dismutase and a higher malondialdehyde content than the control in the liver. Salinity stress significantly increased the serum glucose but decreased the liver glycogen. The activities of glucokinase and phosphofructokinase in the liver and gills were significantly higher in the 20 psu group, indicating that glycolysis could be significantly enhanced by salinity stress. The activities of glucose-6-phosphate synthase and phosphoenolpyruvate carboxykinase in the liver were significantly decreased by salinity stress. The expressions of myo-inositol-1-phosphate synthase and myo-inositol monophosphatase were significantly up-regulated in the gills and kidney. However, the expressions of these two genes were significantly down-regulated in the liver. The myo-inositol content in the gills, kidney and liver in the 20 psu group were significantly increased by salinity stress. This study indicates that salinity stress can impair the gill structure and reduce the antioxidant capacity of O. mossambicus. The changes in MI biosynthesis and carbohydrate metabolism could be an effective strategy to alleviate the adverse effect of salinity stress.

While a digestive tract is known to harbor complex assemblages of microbiota, maintaining a functional, stable microbial community is important to the host's health but can be constantly influenced by various environmental factors. Salinity can lead to stress, including hyposaline or hypersaline stress to aquatic animals, which influence the growth condition of the animals. However, the relationship among the salinity, intestinal microbiota and growth condition of the aquatic animals remains unclear. In this study, two euryhaline species, Oreochromis niloticus (Nile tilapia) and Litopenaeus vannamei (Pacific white shrimp) were reared in water with different salinity and the growth condition verified that Nile tilapia and Pacific white shrimp had reverse salinity preference. The gut microbiota of Nile tilapia and Pacific white shrimp were compared by using 16S rRNA gene Illumina sequencing. Analysis of more than 280,000 quality-filtered sequences obtained from guts of Nile tilapia and Pacific white shrimp reared in different salinities showed that both host phylogeny and water salinity influenced the intestinal microbiota composition. Redundancy analysis combined with the heat map analysis indicated that among the shared operational taxonomy units (OTUs) in both Nile tilapia and Pacific white shrimp, 14 OTUs increased while 10 OTUs decreased in abundance toward to the increase of salt concentration. The proportion of bacteria regarded as opportunists increased while those regarded as commensal or beneficial bacteria decreased when the host facing hyposaline or hypersaline stress. The alteration of intestinal microbiota was likely attributed to the environmental selection for microbes that could grow better under high or low salinity, the host response to the salinity stress and subsequent stress exerting on the gut microbiota, or both. Statement of relevance This manuscript studied the correlation between the intestinal microbiota and two euryhaline aquatic animals, Oreochromis niloticus (Nile tilapia) and Litopenaeus vannamei (Pacific white shrimp).

Suppressor of cytokine signaling (SOCS) proteins are inverse feedback regulators of cytokine and hormone signaling mediated by the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway that are involved in immunity, growth and development of organisms. In the present study, three SOCS genes, SOCS-1, SOCS-2 and SOCS-3, were identified in an economically important fish, Nile tilapia (Oreochromis niloticus) referred to as NtSOCS-1, NtSOCS-2 and NtSOCS-3. Multiple alignments showed that, the three SOCS molecules share highly conserved functional domains, including the SRC homology 2 (SH2) domain, the extended SH2 subdomain (ESS) and the SOCS box with others vertebrate counterparts. Phylogenetic analysis indicated that NtSOCS-1, 2 and 3 belong to the SOCS type II subfamily. Whereas NtSOCS-1 and 3 showed close evolutionary relationship with Perciformes, NtSOCS-2 was more related to Salmoniformes. Tissue specific expression results showed that, NtSOCS-1, 2 and 3 were constitutively expressed in all nine tissues examined. NtSOCS-1 and 3 were highly expressed in immune-related tissues, such as gills, foregut and head kidney. However, NtSOCS-2 was superlatively expressed in liver, brain and heart. In vivo, NtSOCS-1 and 3 mRNA levels were up-regulated after lipopolysaccharide (LPS) challenge while NtSOCS-2 was down-regulated. In vitro, LPS stimulation increased NtSOCS-3 mRNA expression, however it inhibited the transcription of NtSOCS-1 and 2. Collectively, our findings suggest that, the NtSOCS-1 and 3 might play significant role(s) in innate immune response, while NtSOCS-2 may be more involved in metabolic regulation.

Porous In 2 O 3 nanocuboids were synthesized successfully on a large scale and characterized with XRD, TG–DTA, BET, FESEM and TEM. The precursors – In(OH) 3 nanocuboids, which were first produced in the nanoreactors consisting of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) surfactant and In 3+ ions, can transform topotactically to form porous In 2 O 3 nanocuboids, after annealed at 300 °C. The gas sensing performances of the materials were also investigated before and after modified with Pd nanoparticles. The chemical sensors made with Pd@In 2 O 3 nanocuboids exhibit enhanced performances in detecting reducing gases such as acetone, compared to those fabricated with pure porous In 2 O 3 nanocuboids.

As an effective feed additive in the livestock industry, olaquindox (OLA) has been widely used in domestic animal production. However, it is unclear whether OLA has negative effects on mammalian oocyte quality and fetal development. In this study, toxic effects of OLA were tested by intragastric gavage ICR mice with water, low-dose OLA (5 mg/kg/day), or high-dose OLA (60 mg/kg/day) for continuous 45 days. Results showed that high-dose OLA gavage severely affected the offspring birth and growth. Significantly, high-dose OLA impaired oocyte maturation and early embryo development, indicated by the decreased percentage of germinal vesicle breakdown, first polar body extrusion and blastocyst formation. Meanwhile, oxidative stress levels were increased in oocytes or ovaries, indexed by the increased levels of ROS, MDA, H2O2, NO, and decreased levels of GSH, SOD, CAT, GSH-Px and GSH-Rd. Furthermore, aberrant mitochondria distribution, defective spindle assembly, abnormal H3K4me2/H3K9me3 levels, increased DNA double-strand breaks and early apoptosis rate, were observed after high-dose OLA gavage. Taken together, our results for the first time illustrated that high-dose OLA gavage led to sub-fertility of females, which means that restricted utilization of OLA as feed additive should be considered.

High energy diets (HED) have been widely used in farmed fish, but HED also caused some metabolic diseases. The rapamycin-induced inhibition of mechanistic target of rapamycin (mTOR) signalling has been verified to alleviate metabolic syndromes in mammals, however, the functions of rapamycin in regulating metabolism in the fish fed with HED has not been well investigated. In the present 8-week feeding trial, Nile tilapia were fed with a normal diet with medium fat and medium carbohydrate (MFMC), a high fat and high carbohydrate (HFHC) diet, or the HFHC diet supplemented with rapamycin (Rap). Compared to MFMC diet, the HFHC diet significantly increased phosphorylation of mTOR protein, lipid deposition in tissues, glycogen degradation, oxidative stress and inflammation, but decreased lipid catabolism capability. The supplementation of Rap in the HFHC diet inhibited phosphorylation of mTOR protein and protein synthesis, but elevated protein catabolism. Rap addition also increased catabolism of lipid and carbohydrate, reduced oxidative stress and inflammation, and promoted autophagic activities, meaning Rap addition could alleviate the most of the adverse effects caused by the HFHC diet. All these indicate that the elevated mTOR activity was highly correlated to the adverse effects of HFHC diet on physiological functions in fish, and the inhibition of mTOR activity could largely help to maintain normal physiological status in the HED-fed fish. Therefore, mTOR could be a promising regulatory target to alleviate the metabolic dysfunctions caused by HED in fish, however, the possible negative effects of TOR pathway regulation on protein retention and growth should also be carefully evaluated in practices.

High-fat diet (HFD) caused some adverse effects in farmed fish, thus the adaptation to HFD in fish is an important research topic. This study was conducted to examine the roles of carnitine and its related mitochondrial fatty acid β-oxidation (FAO) in the adaptation to HFD in Nile tilapia. Nile tilapias were fed with HFD (13 %), HFD + mildronate (HFD + MD, inhibitor of carnitine synthesis, 1000 mg/kg body per day) or a normal fat diet (NFD, 7 %) for eight weeks. After the feeding trail, the fish fed with HFD showed higher hepatic free carnitine content and FAO activities, and similar levels of serum triglyceride (TG) and whole body fat. However, the HFD + MD-fed fish remarkably decreased carnitine content and FAO efficiency in tissues than those in the HFD-fed fish, and increased contents of serum free fatty acids (FFA) and TG, whole body fat and hepatic TG. Moreover, the HFD-fed fish upregulated the expressions of the genes associated to FAO, lipid transport and lipolysis. Nevertheless, the fish fed with HFD + MD showed lower transcriptional levels of the genes related to lipolysis and lipid transport, and higher lipogenesis genes. These results indicate that the adaptive changes in the fish fed with HFD were eliminated by dietary MD supplementation, and show that carnitine and its related FAO activity play important roles in the adaptation to HFD in fish. This study illustrates that in the practical usage of HFD in aquaculture, the endogenous carnitine concentration and mitochondrial FAO activities should be important checkpoints. Keywords: Adaptation, L-carnitine, High-fat diet, Lipid deposition, Nile tilapia

Intestinal microbiota plays profound roles in host nutrition, physiology, and evolution. The development of DNA sequencing technologies has increased dramatically research on fish intestinal microbiota. However, most studies conducted so far have focused on the microbial structure and diversity. Studies targeting the exact function of commensal microbes in aquatic animals are still scarce, which limits the application of microbiota related knowledge in aquaculture. Gnotobiotic models (animals cultured in axenic conditions or with defined microbial lineages) are excellent tools for identifying the molecular interactions between intestinal microbiota and host, which drive studies of microbiota from correlation to causality in mammals. In recent decades, gnotobiotic fish models have been established and applied in aquaculture research. This review summarizes the colonization conditions in gnotobiotic zebrafish model and its application in understanding intestinal microbiota-host interactions in aquaculture. Furthermore, methods and research progress on other gnotobiotic models including freshwater and marine fishes, molluscs and crustaceans are also discussed. Application of gnotobiotic models in aquaculture has deepened our understanding of the relationship between the host and intestinal microbiota, which will facilitate the modulation of intestinal microbiota for production of healthy animals and sustainable development of aquaculture.

The requirements of essential fatty acids (EFAs) varies among fish species, however, the possible different cellular metabolism patterns of EFAs among fish species have not been well addressed. In the present study, we compared activities of cellular FA uptake, β-oxidation and esterification towards [1–14C]-labeled linoleic acid (LA, 18:2n-6) and linolenic acid (LNA, 18:3n-3) in the primary hepatocytes between grass carp (GCH) and Nile tilapia (NTH), which are two freshwater fish but have specific requirement of LNA or LA, respectively. The results showed that LNA had a higher FA-serum binding efficiency than LA in both GCH and NTH. GCH preferentially took up LNA, while NTH primarily took up LA. Both GCH and NTH had higher β-oxidation activity to LA than to LNA. LNA caused higher esterification than LA in GCH, but LA and LNA caused similar esterification effects in NTH. In GCH, LNA tended to induce higher expressions of the genes related to lipid transportation and lipogenesis, but lowered expressions of the lipid catabolism-related genes. However, the regulation of LNA or LA on gene expressions in NTH was marginal. Taken together, GCH had specific preference to take up and esterify LNA, while NTH preferentially took up LA. These differences are in accordance with the specific EFA requirements of grass carp and Nile tilapia. Our study provides new information for understanding the relationships between the specific EFA requirements and cellular metabolism of EFAs in fish.

Shanghai is a Chinese megacity in the Yangtze River Delta area, one of the most polluted coastal areas in China. The inhabitants of Shanghai have very high aquatic product consumption rates. A risk-benefit assessment of the co-ingestion of fish nutrients and contaminants has not previously been performed for Shanghai residents. Samples of five farmed fish species (marine and freshwater) with different feeding habits were collected from Shanghai markets in winter and summer. Fatty acids, protein, mercury, cadmium, lead, copper, polychlorinated biphenyls, hexachlorocyclohexanes, and dichlorodiphenyltrichloroethanes were measured in liver, abdominal fat, and dorsal, abdominal, and tail muscles from fish. Tolerable daily intakes and benefit-risk quotients were calculated to allow the benefits and risks of co-ingesting n-3 long-chain polyunsaturated fatty acids and contaminants to be assessed according to the cancer slope factors and reference doses of selected pollutants. All of the contaminant concentrations in the muscle tissues were much lower than the national maximum limits, but the livers generally contained high Hg concentrations, exceeding the regulatory limit. The organic pollutant and n-3 long-chain polyunsaturated fatty acid concentrations correlated with the lipid contents of the fish tissues, and were higher in carnivorous marine fish than in omnivorous and herbivorous freshwater fish. The tolerable daily intakes, risk-benefit quotients, and current daily aquatic product intakes for residents of large Chinese cities indicated that the muscle tissues of most of the fish analyzed can be consumed regularly without significant contaminant-related risks to health. However, attention should be paid to the potential risks posed by dichlorodiphenyltrichloroethane in large yellow croaker and Hg in tilapia. Based on the results of this study, we encourage people to consume equal portions of marine and freshwater fish.

The accumulation of excess fat in fish would impair fish health and has been a serious problem in cultured fishes. Adipose tissues are specific tissues for fat deposit in many fish species, therefore the knowledge of the anatomic distribution and total mass of adipose tissues is the basic premise to study the mechanism of fat accumulation in economic fishes. However, this issue has not been well documented. To investigate the morphology of adipose tissues in fishes, a T1-weighted magnetic resonance imaging (MRI) technique was developed to scan grass carp, turbot, tilapia, pompano and large yellow croaker. Three-dimensional (3-D) images that quantitatively integrated the total volumes of adipose tissues in these fish were constructed for the first time. From 2-D and 3-D MRI images, we identified two patterns of adipose tissue distribution in fish: visceral adipose tissue dominant (grass carp, tilapia, pompano and large yellow croaker) and subcutaneous adipose tissue dominant (turbot). The volumes of adipose tissues assessed by MRI were highly consistent with those obtained by traditional dissection. In a fasting experiment on tilapia, the MRI signal of mesenteric adipose tissues successfully distinguished between fish before and after 28-d starvation. Although our MRI technique has limitations for measuring lipid in organs not specifically dedicated to fat storage, e.g., liver, muscle and intestine, the method will help researchers to gain insights into the distribution, size, volume and shape of the adipose tissues in intact and live fish. This could be a powerful tool in future studies of fish lipid metabolism. Statement of relevance to aquaculture In aquaculture, the accumulation of excess fat in fish, which is mainly sourced from unbalanced diets or feeding strategy, would impair fish health and has been a serious problem in cultured fishes. Adipose tissues are specific tissues for fat deposit in many fishes, therefore the knowledge of the anatomic distribution and total mass of adipose tissues is the basic premise to study the mechanism of fat accumulation in economic fishes. However, this issue has not been well documented. Our present work investigated the distribution and content of adipose tissues in five economic fishes with different feed habits and farming environments by using the MRI technique. Through this work, we described the shape, distribution and mass of adipose tissues in different economic fishes for the first time. We also developed an ideal MRI scanning method for live fish, which largely expends the application of the MRI technique in nutrient physiological study in aquatic animals. Because the adipose tissue has been widely accepted to be closely related to nutrition status and diets in the most of farmed animals, including economic fishes in aquaculture, our present study has close relevance to aquaculture.

article i nfo Article history: An 8-week feeding trial was conducted to investigate the optimum dietary vitamin B12 requirement of juve- nile Chinese mitten crab, Eriocheir sinensis, and its effect on non-specific immunity responses and resistance against Aeromonas hydrophila. Vitamin B12 was supplemented to the basal diet at 0, 0.05, 0.1, 0.2, 0.4, 0.8 and 1.6 mg/kg to formulate seven semi-purified diets. A diet free of vitamin B12 and folic acid was also included as a control. Each diet was fed to E. sinensis (0.051 ± 0.001 g) in four replicates, followed by a challenge study for 2 weeks. Relative growth rate and specific growth rate were best in crabs fed 0.2 and 0.4 mg vitamin B12/kg diets, followed by the 0.1, 0.8, 0, 0.05 and 1.6 mg/kg groups and lowest in the control group (vitamin B12 and folic acid free). Feed efficiency and survival rate peaked at the supplementation of 0.2 mg/kg. The whole body crude protein of juvenile crabs was significantly higher when crabs fed 0.2-0.8 mg vitamin B12/kg than those fed the diets without vitamin B12 supplementation. Total hemocyte count was significantly higher in crabs fed 0.2 and 0.4 mg vitamin B12/kg than those in the other feeding groups, and crabs fed the 0.2 mg/kg diet had the highest phenoloxidase, lysozyme, acid phosphatase and alkaline phosphatase activities but the lowest cumula- tivemortality.Hepatopancreaticvitamin B12concentration increased asthe level ofvitaminB12 supplementation increased. The optimum dietary vitamin B12 requirement by E. sinensis is recommended at 0.20-0.22 mg/kg diet. © 2014 Elsevier B.V. All rights reserved.

Even though the Pacific white shrimp is a very important culture species, there is little information on the effect of feed nutrients on the intestinal microbiota. In shrimp, dietary fatty acids largely affect the growth and immune system of Litopenaeus vannamei in part by changing the intestinal bacterial profile. Therefore, an Illumina-based sequencing method was used to examine the intestinal bacterial composition of L. vannamei following six diets with different lipid sources. The bacterial communities in the culture water and shrimp intestinal contents were also compared. The results revealed that shrimp fed a diet with an equal combination of soybean oil, beef tallow, and linseed oil (SBL) had significantly higher weight gain and survival rate than those fed with soybean oil or beef tallow. Proteobacteria and Tenericutes were dominant in the intestines of L. vannamei regardless of the diet. There was a significant prevalence of Rhizobiaceae in shrimp fed the SBL diet than in shrimp fed diets with soybean oil or beef tallow. Proteobacteria dominated in both the culture water and shrimp intestinal samples of L. vannamei. These results suggest that the host intestinal environment imposes selective pressure on the establishment of microbial communities. Lipid sources with different fatty acid compositions could affect the composition of the intestinal microbiota of L. vannamei.

Environmental estrogenic compounds are important pollutants, which are widely distributed in natural water bodies. They produce various adverse effects on fish, but their concentration-dependent toxicities in fish metabolism and health are not fully understood. This study investigated the effects of 17β-estradiol (E2) and bisphenol A (BPA) at low and high concentrations on lipid deposition, inflammation and antioxidant response in male zebrafish. We measured fish growth parameters, gonad development, lipid contents and the activities of inflammatory and antioxidant enzymes, as well as their mRNA expressions. All E2 and BPA concentrations used increased body weight, damaged gonad structure and induced feminization in male zebrafish. The exposure of zebrafish to E2 and BPA promoted lipid accumulation by increasing total fat, liver triglycerides and free fatty acid contents, and also upregulated lipogenic genes expression, although they decreased total cholesterol content. Notably, zebrafish exposed to low concentrations of E2 (200 ng/L) and BPA (100 μg/L) had higher lipid synthesis and deposition compared to high concentrations (2000 ng/L and 2000 μg/L, respectively). However, the high concentrations of E2 and BPA increased inflammation and antioxidant response. Furthermore, BPA caused greater damage to fish gonad development and more severe lipid peroxidation compared to E2. Overall, the results suggest that the toxic effects of E2 and BPA on zebrafish are concentration-dependent such that, the relative low concentrations used induced lipid deposition, whereas the high ones caused adverse effects on inflammation and antioxidant response.

Recent studies showed that nitric oxide (NO) functions as an essential endogenous plant signal molecule. In this study, the regulatory role of NO during the flower senescence of cut rose (Rosa hybrida L. ‘Kardinal’) was surveyed. Exogenous application of the NO donor sodium nitroprusside (SNP) could increase vase life and maximum flower diameter and its effects were dose and time dependent. Treatments with 200 μM of SNP for 24 h obtained the maximum vase life and flower diameter. NO scavengers 2-(4-carboxy-2-phenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl- 3-oxide (cPTIO) or methylene blue (MB-1) and NO synthase (NOS) inhibitors N-nitro- l -arginine methyl ester ( l -NAME) or S,S′-1,3-phenylene-bis(1,2-ethanediyl) -bis-isothiourea (PBITU) reversed the positive effects of exogenous NO. Meanwhile, cPTIO, MB-1, l -NAME, or PBITU alone significantly decreased the vase life, indicating that endogenous NO may play specific roles in cut flower senescence. Exogenous NO decreased 1-aminocyclopro-pane-1- carboxylate oxidase (ACO) activity and ethylene production, and cPTIO was able to prevent the negative effects of NO. This implies that NO may act as an antagonist to ethylene in the senescence of cut rose flowers. Ethylene inhibitors 1-methylcyclopropene (1-MCP) improved vase life and maximum flower diameter, but the promotive effects of 1-MCP could be partially reversed by cPTIO, MB-1, or l -NAME, suggesting that endogenous NO in cut rose flowers may play a crucial role in the cut rose flowers senescence regulated by ethylene. Additionally, 1-MCP treatments increased NOS activity and endogenous NO production, while depressing ACO activity and ethylene production in cut rose. Thus, NO might decrease ethylene output by inhibiting ACO activity in cut rose flowers, thereby vase life being increased. Altogether, the results suggest that NO may function as a signal molecule involved in the senescence of cut rose regulated by ethylene.

The cobalt(II)–lanthanide(III) heteronuclear complexes [Ln(H2O)4Co2(TTHA)(SCN)2]·H3O+ (H6TTHA = triethylenetetraaminehexaacetic acid, Ln = La(2), Ce(3)) have been synthesized based on a binuclear building block of [Co2(H2TTHA)(H2O)2] in [Co2(H2TTHA)(H2O)2]·4H2O (1). Single-crystal structures show that complex 1 is a binuclear complex, containing the [Co2(H2TTHA)(H2O)2] unit as a useful building block. Adding the La3 + and Ce3 + ions to this synthesis system, two new 3d-4f mixed complexes 2 and 3 were obtained. Complexes 2 and 3 show 3D framework, comprising an infinite 1D (one-dimensional) chain based on heterometallic Ln2Co2 (Ln = La(2), Ce(3)). Further investigations such as IR spectra, UV–vis spectra, TGA, XRD and magnetic properties were studied.