Effect of Schizochytrium limacinum supplementation to a low fish-meal diet on growth performance, lipid metabolism, apoptosis, autophagy and intestinal histology of Litopenaeus vannamei

In this experiment, we aimed to evaluate the relationship between the addition of Schizochytrium limacinum to low fish meal diets on growth performance, apoptosis, autophagy, lipid metabolism, and intestinal health of Lipenaeus vanamei. The diet containing 25% fish meal was used as a positive control (FM) and the other three diets contained 15% fish meal and were supplemented with 0, 0.3, and 0.6% S. Limacinum (LF, LFLD, LFHD). The shrimp (0.22 ± 0.00 g) were divided into four replicates of 40 shrimp per tank and fed four times daily to apparent satiation for 8 weeks. Results showed that the final weight (FBW) and weight gain rate (WGR) of shrimp fed FM and LFHD diets were significantly increased compared to those fed the LFLD diet (P<0.05), and there was no significant difference in survival rate (SR) and feed conversion rate (FCR) among the groups (P>0.05). Supplementation of S. Limacinum in low fish meal diets had no effects on shrimp body composition (P<0.05). There were significant differences (P<0.05) in low-density lipoprotein (LDL-C) glucose (GLU), triglycerides (TG), and total cholesterol (TC) in the hemolymph of shrimp fed the LF diet compared to those fed the LFLD and LFHD diets. HE staining and transmission electron microscopy (TEM) results showed that the microvilli height, mucosal folds height, mucosal folds width and muscle layer thickness in the intestine of shrimp fed the LF diet were significantly reduced compared to those fed the other three diets (P<0.05). Swelling of the endoplasmic reticulum and irregular mitochondria in the gut of shrimp fed the LF diet was also observed by TEM, and the endoplasmic reticulum and mitochondria of shrimp fed the LFHD diet returned to a healthy state. Hepatopancreas genes expression results were showed that the gene expression of 5′ -AMP-activated protein kinase (ampk), stearoyl-CoA desaturase (scd1), acetyl-CoA carboxylase 1 (acc1), and malonyl-CoA decarboxylase (mcd) of shrimp fed the LF diet was significantly increased compared to those fed the FM diet (P<0.05). The gene expression of sterol regulatory element-binding protein (srbep) and carnitine palmitoyl transferase 1 (cpt-1) of shrimp fed the LFLD diet was significantly increased compared to those fed the LF diet (P<0.05). The gene expression of acc1, mcd and scd1 of shrimp fed the LFHD diet was significantly reduced compared to those fed the LF diet (P<0.05). Results of genes expression associated with apoptosis in the hepatopancreas showed that the gene expression of B lymphocytoma-2 (bcl-2), BCL2 associated X apoptosis regulator (bax) and cysteinyl aspartate specific proteinase 8 (caspase 8) of shrimp fed the LF diet was significantly reduced compared to those fed the FM diet (P<0.05). The gene expression of bcl-2 of shrimp fed the LFHD diet was significantly reduced compared to those fed the LF diet (P<0.05). Genes related to autophagy in the hepatopancreas showed that the expression of autophagy-related protein 12 (atg 12), autophagy-related protein 13 (atg 13) and beclin1 of shrimp fed LF the diet was significantly reduced compared to those fed the FM diet (P<0.05). The gene expression of atg 12 and atg 13 of shrimp fed the LFHD diet was significantly increased compared to those fed the LF diet (P<0.05). In summary, reducing fish meal is detrimental to the growth performance and intestinal health of shrimp, and 0.6% S. Limacinum supplementation can improve the growth performance, promotes hepatopancreas lipid metabolism, reduces apoptosis, promotes autophagy and improve intestinal health of Litopenaeus vannamei

Glucose Uptake Is Increased by Estradiol Dipropionate in L6 Skeletal Muscle Cells

GLUT4 is an important glucose transporter, which is closely related to insulin resistance and type 2 diabetes. In this study, we investigated the mechanism of Estradiol Dipropionate (EDP) on uptake of glucose in L6 skeletal muscle cells. In our study, we confirmed that EDP promoted uptake of glucose in L6 skeletal muscle cells in both normal and insulin resistant models. Western blot indicated that EDP accelerated GLUT4 expression and significantly activated AMPK and PKC phosphorylation; the expression of GLUT4 was significantly inhibited by AMPK inhibitor compound C and PKC inhibitor Gö6983, but not by Wortmannin (Akt inhibitor). Meanwhile, EDP boosted GLUT4 expression, and also increased intracellular Ca2+ levels. In the presence of 2 mM, 0 mM extracellular Ca2+ and 0 mM extracellular Ca2+ + BAPTA-AM, the involvement of intracellular Ca2+ levels contribute to EDP-induced GLUT4 expression and fusion with plasma membrane. Therefore, this study investigated whether EDP promoted GLUT4 expression through AMPK and PKC signaling pathways, thereby enhancing GLUT4 uptake of glucose and fusion into plasma membrane in L6 skeletal muscle cells. In addition, both EDP induced GLUT4 translocation and uptake of glucose were Ca2+ dependent. These findings suggested that EDP may be potential drug for the treatment of type 2 diabetes

Pressure-Steam Heat Treatment-Enhanced Anti-Mildew Property of Arc-Shaped Bamboo Sheets

Bamboo is one of the most promising biomass materials in the world. However, the poor anti-mildew property and poor dimensional stability limits its outdoor applications. Current scholars focus on the modification of bamboo through heat treatment. Arc-shaped bamboo sheets are new bamboo products for special decoration in daily life. In this paper, we reported pressure-steam heat treatment and explored the effect of pressure-steam on the micro-structure, crystallinity index, anti-mildew, chemical composition, physical properties, and mechanical properties of bamboo via X-ray diffractometer (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), wet chemistry method and nanoindentation (NI). Herein, saturated-steam heat treatment was applied for modified moso bamboo for enhancing the anti-mildew properties and mechanical properties of moso bamboo. Results showed that with the introduction of saturated steam, the content of hemicellulose and cellulose decreased, while the lignin-relative content increased significantly. The anti-mildew property of moso bamboo was enhanced due to the decomposition of polysaccharide. Last, the modulus of elasticity and hardness of treated moso bamboo cell walls were enhanced after saturated-steam heat treatment. For example, the MOE of the treated moso bamboo cell wall increased from 12.7 GPa to 15.7 GPa. This heat treatment strategy can enhance the anti-mildew property of moso bamboo and can gain more attention from entrepreneurs and scholars

Study of the Interaction between Yellow River Water and Groundwater in Henan Province, China

Determining the interaction between surface water and groundwater is crucial for the protection of groundwater resources. Based on the data of natural geography, geological and hydrogeological conditions, environmental isotopes, and groundwater hydrochemical components, we investigated the interaction between Yellow River water and groundwater in Henan Province, China. The recharge range and interaction amount of the groundwater aquifer from the Yellow River lateral seepage were also analysed, and the influence of the lateral seepage of the Yellow River on groundwater hydrochemical type was studied. The results showed that, firstly the transverse seepage range of the north bank of the Yellow River was larger (approximately 20 km) than that of the south bank (approximately 10 km). The main groundwater recharge sources were atmospheric precipitation and the Yellow River, of which the latter accounted for 50.1%. Secondly, in Sections 1–4, the lateral seepage amounts in the north bank were 1476.94, 505.89, 40.88, and 65.7 m3/a·m, respectively. The single-width permeability of typical Section 2 was larger upstream than downstream and larger in the north than in the south. Thirdly, the lateral seepage of the Yellow River significantly influenced the hydrochemical types of groundwater. From upstream to downstream and from proximal to distal location from the Yellow River, the hydrochemical types changed from single to complex and the salinity increased gradually. Fourthly, the annual average lateral seepage groundwater recharge quantity of the Yellow River was 25,114.36 × 104 m3/a between 2001–2019

Study of the Interaction between Yellow River Water and Groundwater in Henan Province, China

Determining the interaction between surface water and groundwater is crucial for the protection of groundwater resources. Based on the data of natural geography, geological and hydrogeological conditions, environmental isotopes, and groundwater hydrochemical components, we investigated the interaction between Yellow River water and groundwater in Henan Province, China. The recharge range and interaction amount of the groundwater aquifer from the Yellow River lateral seepage were also analysed, and the influence of the lateral seepage of the Yellow River on groundwater hydrochemical type was studied. The results showed that, firstly the transverse seepage range of the north bank of the Yellow River was larger (approximately 20 km) than that of the south bank (approximately 10 km). The main groundwater recharge sources were atmospheric precipitation and the Yellow River, of which the latter accounted for 50.1%. Secondly, in Sections 1–4, the lateral seepage amounts in the north bank were 1476.94, 505.89, 40.88, and 65.7 m3/a·m, respectively. The single-width permeability of typical Section 2 was larger upstream than downstream and larger in the north than in the south. Thirdly, the lateral seepage of the Yellow River significantly influenced the hydrochemical types of groundwater. From upstream to downstream and from proximal to distal location from the Yellow River, the hydrochemical types changed from single to complex and the salinity increased gradually. Fourthly, the annual average lateral seepage groundwater recharge quantity of the Yellow River was 25,114.36 × 104 m3/a between 2001–2019

Andrographolide Promotes Uptake of Glucose and GLUT4 Transport through the PKC Pathway in L6 Cells

Glucose transporter 4 (GLUT4) is a membrane protein that regulates blood glucose balance and is closely related to type 2 diabetes. Andrographolide (AND) is a diterpene lactone extracted from herbal medicine Andrographis paniculata, which has a variety of biological activities. In this study, the antidiabetic effect of AND in L6 cells and its mechanism were investigated. The uptake of glucose of L6 cells was detected by a glucose assay kit. The expression of GLUT4 and phosphorylation of protein kinase B (PKB/Akt), AMP-dependent protein kinase (AMPK), and protein kinase C (PKC) were detected by Western blot. At the same time, the intracellular Ca2+ levels and GLUT4 translocation in myc-GLUT4-mOrange-L6 cells were detected by confocal laser scanning microscopy. The results showed that AND enhanced the uptake of glucose, GLUT4 expression and fusion with plasma membrane in L6 cells. Meanwhile, AND also significantly activated the phosphorylation of AMPK and PKC and increased the concentration of intracellular Ca2+. AND-induced GLUT4 expression was significantly inhibited by a PKC inhibitor (Gö6983). In addition, in the case of 0 mM extracellular Ca2+ and 0 mM extracellular Ca2+ + 10 μM BAPTA-AM (intracellular Ca2+ chelator), AND induced the translocation of GLUT4, and the uptake of glucose was significantly inhibited. Therefore, we concluded that AND promoted the expression of GLUT4 and its fusion with plasma membrane in L6 cells through PKC pathways in a Ca2+—dependent manner, thereby increasing the uptake of glucose

Schizochytrium limacinum altered antioxidant capacity and transcriptome profiles in Pacific white shrimp fed a low-fishmeal diet

Dietary low-fishmeal (FM) have negative impacts on growth performance and metabolic responses in aquatic animals, while Schizochytrium limacinum have multiple benefits due to its rich contents of docosahexaenoic acid (DHA). However, little information is available on the effects of S. limacinum on Pacific white shrimp (Litopenaeus vannamei) in a low-FM diet (LF). An 8-week feeding trial were used to investigate the impacts of S. limacinum on growth performance, as well as morphological changes, biochemical indicators, antioxidant capacity, and transcriptomic profiles of hepatopancreas in shrimp fed a low-FM diet. Compared to LF diet, 0.3% S. limacinum (LFLD) diet significantly decreased the specific growth rate (SGR), and did not affect the feed conversion rate (FCR) and weight gain rate (WGR); whereas 0.6% S. limacinum (LFHD) diet did not affect the SGR, FCR and WGR. Histological structures of hepatopancreas showed that LFLD and LFHD treatments reduced the number and size of secretory cells and increased the number of storage cells, compared to LF group. LFLD and LFHD diets significantly decreased the concentrations of triglyceride and total cholesterol, significantly increased the levels of glutathione peroxidase and total antioxidative capacity, while did not affect the levels of malondialdehyde and superoxide dismutase. A total of 135 differential expression genes (DEGs) were identified in LFLD group and 108 DEGs were identified in LFHD group (both compared to LF group). Administration of S. limacinum altered the transcriptomic profiles, while LFHD induced a pattern similar to that of LF. LFLD and LFHD treatments mainly affected the 9 KEGG metabolic pathways, including “Arachidonic acid metabolism” and “Glutathione metabolism”. In conclusion, LFLD treatment impaired the growth performance of shrimp, while LFHD treatment did not affect it; and both treatments improved the morphological structure, lipid accumulation and antioxidant capacity of hepatopancreas

Germacrone Inhibits Cell Proliferation and Induces Apoptosis in Human Esophageal Squamous Cell Carcinoma Cells

Germacrone, a natural 10-membered monocyclic sesquiterpene with three double bonds and a ketone, was isolated from the roots of traditional Chinese medicine Saussurea costus (SC). The pharmacological value and intrinsic mechanism of germacrone in the treatment of esophageal squamous cell carcinoma (ESCC) are still unclear. Therefore, in this study, we further explored the internal molecular mechanism by which germacrone exerts its antiproliferation and antimigration ability against ESCC. 3-(4,5-Dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assays showed that germacrone dose-dependently inhibited the proliferation of ESCC cells. Flow cytometry analysis (FACS) and wound healing experiments on germacrone treated ESCC cells showed that germacrone could induce apoptosis and inhibit the migration of ESCC cells in a dose-dependent manner. In the study on the mechanism of action of germacrone in antiesophageal cancer, we found that germacrone increased the ratio of Bax/Bcl-2 in the cytoplasm of ESCC, resulting in the activation of Caspase-9 and Caspase-3 and decreased the expression of Grp78, thereby reducing the inhibition of Caspase-12 and Caspase-7. In addition, we found that germacrone also inhibited STAT3 phosphorylation in a dose-dependent manner. In conclusion, we determined that germacrone exerted an antiesophageal effect through intrinsic apoptotic signaling pathways and by inhibiting STAT3 activity in ESCC cells

Evaluation of ratios of fish-to-soybean oils on growth, lipid and cholesterol metabolism and muscle metabolites of Pacific white shrimp (Litopenaeus vannamei) fed low fishmeal diets containing Clostridium autoethanogenum protein

The present study aims to investigate the effects of ratios of fish-to-soybean oils in a low fishmeal diet containing Clostridium autoethanogenum protein (CAP) on the growth and metabolism of Litopenaeus vannamei. Four diet groups were designed and the basal diet (FM, 44% crude protein, 8.66% crude lipid, fish-to-soybean oil: 1.5:2.5) contained 25% fishmeal. After 40% of fishmeal protein was replaced by CAP, three different fish-to-soybean oil ratios (4:1, 1:1, and 1:4) were set to formulate three experimental diets, and referred as HF (high fish oil), MF (medium fish oil), and LF (low fish oil), respectively. Shrimp were distributed to four groups of three replicates, each with 40 shrimp in a 300-L tank and they were fed four times daily for 7 weeks before sampling. Results showed that the growth performance of shrimp fed the MF diet was significantly lower than those fed the FM diet, while the shrimp fed the LF diet showed better growth than the HF group. The reduction of the crude lipid content of the whole body, hemolymph total cholesterol (T-CHO), and low-density lipoprotein cholesterol (LDL-C) contents indicated an alteration in the lipid and cholesterol metabolism of shrimp. Compared to the FM group, the mRNA levels of fas in shrimp fed the HF diet were significantly downregulated, while the mRNA levels of delta-24-sr in the HF group were significantly upregulated. In addition, the mRNA levels of hmgcr and scp in shrimp fed the LF diet significantly upregulated compared to the FM group. Metabolomic results showed that multiple metabolic pathways were affected by diet factors, including several amino acid metabolisms, purine metabolism, energy metabolism, and glycerophospholipid metabolism. In conclusion, the reduction of the ratios of fish-to-soybean oils in the low fishmeal diet containing CAP can not only reduce the usage of fish oil and the cost of feed but also maintain the growth performance of shrimp

Hyperkalaemia prevalence and dialysis patterns in Chinese patients on haemodialysis: an interim analysis of a prospective cohort study (PRECEDE-K)

Abstract Background Hyperkalaemia is a known risk factor for cardiac arrhythmia and mortality in patients on haemodialysis. Despite standard adequate haemodialysis, hyperkalaemia is common in patients with end-stage renal disease (ESRD) at interdialytic intervals. Data on hyperkalaemia burden and its effects on dialysis patterns and serum potassium (sK) fluctuations in patients on haemodialysis in China remain limited. The prospective, observational cohort study (PRECEDE-K; NCT04799067) investigated the prevalence, recurrence, and treatment patterns of hyperkalaemia in Chinese patients with ESRD on haemodialysis. Methods Six hundred adult patients were consecutively enrolled from 15 secondary and tertiary hospitals in China. In this interim analysis, we report the baseline characteristics of the cohort, the prevalence of predialysis hyperkalaemia (sK > 5.0 mmol/L), and the trends in serum–dialysate potassium gradient and intradialytic sK shift at Visit 1 (following a long interdialytic interval [LIDI]). Results At baseline, most patients (85.6%) received three-times weekly dialysis; mean duration was 4.0 h. Mean urea reduction ratio was 68.0% and Kt/V was 1.45; 60.0% of patients had prior hyperkalaemia (previous 6 months). At Visit 1, mean predialysis sK was 4.83 mmol/L, and 39.6% of patients had hyperkalaemia. Most patients (97.7%) received a dialysate potassium concentration of 2.0 mmol/L. The serum–dialysate potassium gradient was greater than 3 mmol/L for over 40% of the cohort (1– < 2, 2– < 3, 3– < 4, and ≥ 4 mmol/L in 13.6%, 45.1%, 35.7%, and 5.2% of patients, respectively; mean: 2.8 mmol/L). The intradialytic sK reduction was 1– < 3 mmol/L for most patients (0– < 1, 1– < 2, 2– < 3, and ≥ 3 mmol/L in 24.2%, 62.2%, 12.8%, and 0.9% of patients, respectively; mean: 1.4 mmol/L). Conclusions Hyperkalaemia after a LIDI was common in this real-world cohort of Chinese patients despite standard adequate haemodialysis, and led to large serum–dialysate potassium gradients and intradialytic sK shifts. Previous studies have shown hyperkalaemia and sK fluctuations are highly correlated with poor prognosis. Effective potassium-lowering treatments should be evaluated for the improvement of long-term prognosis through the control of hyperkalaemia and sK fluctuations. Trial registration ClinicalTrials.gov, NCT04799067