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The purpose of this research was to explore the effect of selenium on mercury-mediated apoptosis of follicular granulosa cells in laying hens. Moreover, the ATF6/CHOP pathway was investigated to explore the mechanism in this progress. Hg, Se, and 4-phenyl butyric acid were used alone or in combination to treat the cells. Our results showed that the nuclear in cells became condensate after Hg exposure, while Se addition significantly alleviated this change. Hg exposure significantly induced the apoptosis and the reduction of mitochondrial membrane potential in cells (P < 0.05), Nevertheless co-treatment of Se significantly inhibited these effects (P < 0.05). Additionally, Hg exposure dramatically elevated the gene expressions of Bax/Bcl-2 (P < 0.05), Caspase-3 (P < 0.05), Caspase-9 (P < 0.05), protein kinase RNA-like endoplasmic reticulum kinase (P < 0.05), activating transcription factor 6 (P < 0.05), C/EBP homologous protein (CHOP; P < 0.05), inositol-requiring enzyme 1α (P < 0.05), tumor necrosis factor-associated factor 2 (P < 0.05), activating transcription factor 6 (ATF6; P < 0.05) and apoptosis signal-regulating kinase 1 (P < 0.05) in cells, whereas Se addition reversed these changes. The exposure to Hg considerably boosted the expression of ATF6 and CHOP protein (P < 0.05), while Se addition significantly alleviated above-mentioned enhancements (P < 0.05). In summary, Hg exposure induced apoptosis, which was considerably reduced alleviated by Se addition, which was linked to the ATF6/CHOP pathway in follicular granulosa cells in laying hens.

In this study, we explored the effect of dietary lead nitrate on zootechnical performance, egg quality, accumulation of ovarian plumbum (Pb), follicular atresia rate, and ovarian oxidative stress in laying hens. Furthermore, the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling molecule was studied to reveal the molecular mechanism of the stress. A total of 512 Hy-Line Brown laying hens aged 40 wk were randomly allocated to 4 groups (with 8 pens per group and 16 hens per pen). The Pb concentrations used to treat the 4 groups were 3.20, 33.20, 63.20, and 93.20 mg/kg. The results revealed that dietary Pb exposure significantly linearly reduced the zootechnical performance (P < 0.01) but significantly linearly increased the feed conversion ratio (P < 0.01). The dietary Pb exposure significantly linearly reduced the Haugh units (P < 0.01), albumen height (P < 0.01), eggshell thickness (P < 0.01), and eggshell strength (P < 0.01). In addition, the dietary Pb exposure significantly enhanced the follicular atresia rate (P < 0.01). After dietary Pb exposure, superoxide dismutase (P < 0.01) and glutathione peroxidase (GSH-Px) (P < 0.01) activities and glutathione (P < 0.01) contents were significant decreased quadratically, and there were significant linear decreases in the activities of catalase (CAT) (P < 0.01) and glutathione reductase (GR) (P < 0.01), whereas malondialdehyde content was significantly linearly increased (P < 0.01). In addition, except for manganese superoxide dismutase, the gene expressions of copper-zinc superoxide dismutase (P < 0.01), CAT (P < 0.01), and GR (P < 0.01) were significant decreased linearly. In addition, there were significantly quadratic decreases in the mRNA expressions of GSH-Px (P < 0.01) and Nrf2 (P < 0.01). By way of contrast, the Kelch-like ECH-associated protein 1 (Keap1) gene expression was significantly linearly increased (P < 0.01). In conclusion, dietary Pb exposure could induce oxidative stress by impairing the Nrf2-Keap1 signal pathway in the ovaries of laying hens.

This study investigated that the effect of nano-selenium (nano-Se) addition preventing prehierarchical follicular atresia induced by mercury (Hg) exposure in laying hens. Furthermore, endoplasmic reticulum (ER) stress pathway was explored to reveal the protective mechanism of nano-Se in vitro. The results revealed that Hg could significantly reduce laying performance (P 0.05) and egg quality (P 0.05), whereas nano-Se addition partially reversed the reductions. Besides, Hg significantly induced the deposition of Hg in prehierarchical follicles (P 0.05) and prehierarchical follicular atresia (P 0.05), whereas nano-Se addition could alleviate these toxicities in vitro. In addition, Hg exposure could significantly reduce cell viability (P 0.05) and induce pyknotic nucleus in prehierarchical granulosa cells, while nano-Se addition reversed these effects. The levels of follicle-stimulating hormone (P 0.05), luteinizing hormone (P 0.05), progesterone (P 0.05), and estradiol (P 0.05) were significantly decreased after Hg exposure in vitro. However, nano-Se addition reversed the decreases of sex hormone levels. Furthermore, Hg exposure significantly increased the gene expressions of CHOP (P 0.05), PERK (P 0.05), ATF4 (P 0.05), ATF6 (P 0.05), ASK1 (P 0.05), IRE1α (P 0.05), TRAF2 (P 0.05), caspase-9 (P 0.05), caspase-3 (P 0.05), and Bax/Bcl-2 (P 0.05), whereas nano-Se addition reversed these increases of gene expressions in vitro. In summary, this study provides that Hg can induce prehierarchical follicular atresia, whereas nano-Se addition can ameliorate it, and elucidates an important role of ER stress in nano-Se alleviating prehierarchical follicular atresia induced by Hg in laying hens.

This study evaluated the effect of epigallocatechin-3-gallate (EGCG) alleviating the reduction of antioxidant capacity induced by dietary vanadium (V) in the liver, kidney, and ovary of laying hens. Furthermore, Kelch-like ECH-associated protein 1(Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2)-small Maf proteins (sMaf) pathway was explored to reveal the molecular mechanism. A total of 768 40-week-old Hyline-Brown laying hens were randomly allocated to 4 groups with 8 pens per group and 24 hens per pen. The experimental groups were as follows: control (basal diet); V15, control + 15 mg/kg V; EGCG150, control + 150 mg/kg EGCG; V15 + EGCG150, V15 + 150 mg/kg EGCG. Our results revealed that dietary EGCG supplementation completely alleviated the V-induced reductions of hen-day egg production, average egg weight, Haugh unit, albumen height, eggshell strength, and eggshell thickness. Dietary EGCG supplementation completely prevented the V-induced reductions of serum follicle-stimulating hormone and luteinizing hormone levels. Besides, dietary EGCG supplementation reversed the V-induced increments of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine (Cr), and uric acid (UA). In addition, dietary EGCG supplementation partially alleviated the V-induced reductions of the enzyme activities and gene expressions of superoxidative dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GSH-Px). Furthermore, dietary EGCG supplementation partially alleviated the V-induced reductions of Nrf2 and sMaf gene expressions, and the increments of Keap1 gene expression. In summary, EGCG partially alleviated V-induced reduction of antioxidant capacity through Keap1-Nrf2-sMaf pathway in the liver, kidney, and ovary of laying hens.

International audience; AbstractMandibular gland (MG) secretions of honey bee are synthesized through a three-step bifurcation pathway, and the initiate hydroxylation step is carried out by cytochrome P450 enzymes (P450). We have previously revealed that CYP6AS8 and CYP6AS11 are possibly participating in this process. In this study, we evaluated the function of CYP6AS8 in honey bee worker’s MG using RNA interference technology, and we investigated the expression pattern of CYP6AS8 in MGs from workers of different ages. We found that the expression of CYP6AS8 was detectable in MGs across the whole life cycle of Apis mellifera except for newly emerged workers and predominately expressed at day 15. RNAi knockdown revealed that the production of 10-HDA was synchronized with the expression level of CYP6AS8 in MG of honey bee workers; the downregulation of CYP6AS8 caused a significant reduction of 10-HDA content, demonstrating that CYP6AS8 is indispensable for 10-HDA biosynthesis. Our current results confirm that CYP6AS8 modulates 10-HDA biosynthesis in MGs of western honey bee worker and provided the first evidence to identify the certain P450 participate in the MG secretion biosynthesis of honey bee workers.

Overexpression of the HER2/neu (HER2) is linked to an adverse outcome in ovarian cancer. Short-interfering RNA (siRNA) is a HER2 inhibitor, which in combination with chemotherapy improves survival rate. The aim of this study was to evaluate the efficacy of adenovirus mediated HER2-siRNA in combination with cisplatin (Ad-HER2-siRNA+DDP) on treating HER2-positive ovarian cancer xenografts and explore the effectiveness ofMice with ovarian cancer xenografts were treated with different therapy regimens and imaged at 1, 4, 8, 12, 24, 48, 72, and 96 h postinjection withThe in vivo therapy experiments revealed that tumor weight and volume of Ad-HER2-siRNA+DDP group was the least of all. The IHC results further confirmed that HER2 protein level was significantly downregulated in this group. The results of SPECT imaging showed that the T/B ratios at each time point in Ad-HER2-siRNA +DDP group was the lowest (p0.05).The data demonstrate that the growth of xenografts of human ovarian cancer with high expression of HER2 could be inhibited effectively by Ad-HER2-siRNA+DDP.

The objective of this study was to determine the effects of mercury chloride (HgCl2) on laying performance, egg quality, hepatic and renal histopathology, and serum biochemical profiles in laying hens. A total of 768 Hy-line brown laying hens aged 40 weeks were randomly allocated to four groups (8 pens per group and 24 hens per pen). The concentrations of mercury (Hg) in four groups were 0.280, 3.325, 9.415, and 27.240 mg/kg. Results revealed that dietary Hg could significantly reduce laying performance (P

Monoclonal antibodies (mAbs) such as DD3, raised against progastrin-releasing peptide(31-98) (ProGRP (31-98)) antigen, have been used to target small cell lung cancer (SCLC). However, as an intact mAb, DD3 is cleared slowly from the body, with an optimal radioimmunoimaging time of 72 hours. More recently, a single-chain antibody fragment has demonstrated reduced excretion time in blood and normal tissues and is increasingly used in diagnostic cancer research. Thereby, it potentially increases the radioimmunoimaging efficacy. However, there have been few studies with this antibody fragment. The aim of this study was to characterize the preliminary radioimmunoimaging and biodistribution of (131)I-anti-ProGRP(31-98) scFv in nude mice bearing SCLC xenografts.Anti-ProGRP(31-98) scFv was used to detect ProGRP expression by flow cytometry analysis and immunohistochemistry. (131)I-anti-ProGRP(31-98) scFv was injected intravenously into healthy Kunming mice and the percentage injected dose per gram (%ID/g) in various organs was calculated. Similarly, the %ID/g and tumor/non-tumor ratio in xenograft-bearing mice was calculated. After injection of (131)I-anti-ProGRP(31-98) scFv, treated mice were imaged at 1, 24, and 30 hours. Then the tumor/base ratios were calculated.ProGRP was highly expressed in NCI-H446 cells and xenograft tissue. The metabolism of (131)I-anti-ProGRP(31-98) scFv in healthy mice was consistent with a first-order and two-compartment model; T1/2α and T1/2β were 10.2 minutes and 5 hours 18 minutes, respectively. The %ID/g of (131)I-anti-ProGRP(31-98) scFv in xenografts was much higher than in healthy tissues at 12 hours after injection, reaching a maximum of (5.38±0.92) %ID/g at 24 hours. Successful imaging of xenograft tissue was achieved as early as 1 hour post-injection and persisted until 30 hours, with 24 hours proving optimal.(131)I-anti-ProGRP(31-98) scFv shows highly selective tumor uptake with low accumulation in normal tissues and rapid blood clearance, indicating that it could be a promising agent for SCLC radioimmunoimaging.

The objective of this study is to explore the feasibility of radioiodine treatment for cervical cancer using the early growth response (Egr-1) promoter to control sodium-iodine symporter (hNIS) gene expression. The hNIS gene was previously transfected into Hela cells under the control of either the cytomegalovirus (CMV) or Egr-1 promoters. Na125I uptake was measured in the presence or absence of NaClO4. Na125I efflux was measured. The effects of external beam radiation on iodine uptake and retention were studied. The cytotoxic effects of 131I were measured by clonogenic assay. The Na125I biodistribution was obtained using mice bearing control and transfected cells. The %ID/g of tumor and major organs were obtained for a range of times up to 48 hours post injection and the ratio of tumor to non-tumor activity (T/NT) was calculated. Tumors were imaged with Na131I and 99mTcO4−, and the ratio of tumor to background activity (T/B) was calculated. Na125I uptake in Hela cells was minimal in the absence of hNIS. Uptake in the transfected cells was strong, and could be blocked by NaClO4. The iodine uptake of Hela-Egr-1-hNIS cells increased after the irradiation, and the magnitude of this effect approximately matched the radiation dose delivered. The efflux of 125I was affected by neither the promoter sequence nor pre-irradiation. 131I reduced the clonogenic survival of symporter expressing cells, relative to the parental line. The effect was greatest in cells where hNIS was driven by the CMV promoter. Tumors formed from Hela-Egr-1-hNIS concentrated Na125I over a 12 hour period, in contrast to untransfected cells. These tumors could also be successfully imaged using either Na131I or 99mTcO4−. 131I uptake peaked at 4h, while 99mTcO4− accumulated over approximately 20 hours. In vivo uptake of 131I and 99mTcO4− was slightly higher in cells transfected with the Egr-1 promoter, compared to CMV. Hela-Egr-1-hNIS cells demonstrate highly enhanced iodine uptake, and this effect is further augmented by radiation, creating a positive feedback loop which may bolster radionuclide therapy in vivo.

Bcl-2 is overexpressed in various types of human tumors, including Burkitt's lymphoma, and it is involved in tumorigenesis and chemoresistance, therefore, it is regarded as a potential target of gene therapy. In this study, RNA interference using short hairpin RNA (shRNA)-mediated RNA interference was introduced into Burkitt's lymphoma Raji cells to validate its effects on Bcl-2 expression and cell proliferation in vitro and in vivo. We constructed two types of Bcl-2 shRNA plasmid (pGenesil-1-Bcl-2-1 and pGenesil-1-Bcl-2-2) and negative control shRNA plasmid (pGenesil-1-NC) and stably transfected them into Raji cells. The expression levels of Bcl-2 mRNA and protein were assayed by RT-PCR, flow cytometry and western blotting. Cell proliferation was determined by cell count assay. The antitumor activities and apoptosis of the two types of Bcl-2 shRNA plasmid were evaluated in BALB/c nude mice bearing Burkitt's lymphoma inoculated with Raji cells. The results showed that the expression levels of Bcl-2 mRNA and protein decreased, compared with either the pGenecil-1-NC or the untransfected cell group (P

This study was aimed at investigating the biodistribution and radioimmunoimaging of (131)I-D-D3 in nude mice bearing different types of tumor xenografts. Radioiodination of the D-D3 antibody was performed with the chloramine-T method. The radiochemical purity was determined through thin-layer chromotography. (131)I-D-D3 was injected into healthy Kunming mice via a tail vein, and the %ID/g for various organs was obtained. Similarly, the %ID/g and tumor/nontumor tissue ratio of (131)I-D-D3 in nude mice bearing small cell lung cancer (SCLC) xenografts were obtained. Planar images of (131)I-D-D3 in tumor-bearing nude mice were acquired at different times after injection. The (131)I-D-D3 labeling rate was 86.56% ± 3.8%. The radiochemical purity of (131)I-D-D3 was 99.27% ± 0.6%. After 12 hours of incubation in 37°C water bath, the radiochemical purity was 97.64% ± 0.5% and remained at 88.38% ± 0.4% after 48 hours. After being mixed with healthy human serum for 24 hours, the radiochemical purity was more than 64%. The metabolism of (131)I-D-D3 in healthy Kunming mice was consistent with a two-compartment model with first-order absorption; T(1/2α) and T(1/2β) were 0.25 and 37.89 hours, respectively. The %ID/g of (131)I-D-D3 in SCLC xenografts was much higher than those of other tissues at 48 hours after injection, and the tumor/nontumor tissue ratio also gradually increased with time. After 24 hours of injection, planar imaging was obtained, which clearly showed a contrasting tumor on the right armpit of nude mice bearing SCLC with high concentrations of radioactivity. Also, nude mice bearing gastric cancer showed similar results as that of the SCLC with a lower radioactivity level. No observable accumulation was observed in nude mice bearing pancreatic cancer or lung adenocarcinoma. The labeling rate and radiochemical purity of (131)I-D-D3 were high and stable. (131)I-D-D3 selectively accumulated at tumors that highly expressed progastrin-releasing peptide; therefore, it is a promising radioimmunoimaging reagent for SCLC.