Dietary calcium levels regulate calcium transporter gene expression levels in the small intestine of broiler chickens.

1. This study investigated the effect of dietary calcium (Ca) levels on growth performance, bone development and Ca transporter gene expression levels in the small intestine of broiler chickens.2. On the day of hatch, 350, Ross 308 male broilers were randomly allotted to one of five treatments with five replicate pens each and 14 birds per pen. Dietary Ca levels in feed were 5.0, 7.0, 9.0, 11.0 and 13.0 g/kg, in which 9.0 g/kg was in the control diet. All diets contained 4.5 g/kg non-phytate phosphorus (NPP).3. The increase in dietary Ca levels from 5.0 to 13.0 g/kg did not affect the growth performance of 1- to 18-day-old broilers (P > 0.05).4. Increasing the Ca levels linearly increased the ash weight and the contents of ash, Ca and phosphorus (P) in the tibia of broilers at 18 days of age (P < 0.05). The contents of ash, Ca and P in broilers fed with 9.0 g/kg Ca were higher than those in birds fed with 5.0 g/kg Ca (P < 0.05).5. Increasing the Ca levels linearly decreased mRNA expression levels of the Ca-binding protein 28-kDa (CaBP-D28k), plasma membrane Ca-transporting ATPase 1b (PMCAlb), sodium (Na)/Ca exchanger 1 (NCX1), nuclear vitamin D receptor (nVDR) and membrane vitamin D receptor (mVDR) in the duodenum of broilers at 18 d of age (P < 0.05). Similar results were seen in the jejunum and ileum. Broilers fed 9.0-13.0 g/kg Ca in feed had lower mRNA expression levels of CaBP-D28k and PMCAlb in the small intestine than birds fed 5.0 g/kg Ca in feed (P < 0.05).6. The data indicated that low levels of dietary Ca stimulated its transporter gene transcription and promoted absorption, but high levels of Ca inhibited transporter gene expression and prevented excessive absorption in the small intestine of broiler chickens.

Glycyrrhizin improves bone metabolism in ovariectomized mice via inactivating NF-κB signaling.

OBJECTIVES: Postmenopausal osteoporosis (PMO) is a prevalent metabolic bone disease with high morbidity and serious complications. Here, we studied the effect of glycyrrhizin on bone metabolism using the ovariectomized (OVX) mouse model. METHODS: Osteoclast-related gene expression and osteoclastic function were evaluated in RAW264.7 cells and bone marrow-derived monocytes (BMMs) by real-time polymerase chain reaction and bone resorption assay. For animal studies, female C57BL/6J mice were randomly divided into sham operated, OVX and OVX with glycyrrhizin groups. Bone mass and trabecular microarchitecture were analyzed by micro-computed tomography, dual X-ray absorptiometry, and histomorphometric analysis. Receptor activator of nuclear factor-κB (NF-κB) ligand-induced osteoclastogenesis and the NF-κB signaling pathway were studied by tartrate-resistant acid phosphatase staining and western blotting, respectively. RESULTS: Glycyrrhizin inhibits RANKL-induced expression of Nfatc-1, c-Fos, Trap, Ds-stamp, and Ctsk in RAW264.7 cells. Also, fewer bone resorption pits form when BMMs are incubated in the presence of glycyrrhizin. Glycyrrhizin ameliorates bone loss and improves trabecular bone parameters in OVX mice. BMMs isolated from OVX mice show higher ability of RANKL-induced osteoclastogenesis, which is tremendously reversed by glycyrrhizin. There is significantly higher phosphorylation of IκB-α at Ser32 and NF-κB p65 at Ser536, as well as increased protein levels of c-FOS and NFATc-1 in BMMs of OVX mice, which are all greatly suppressed by glycyrrhizin. CONCLUSIONS: Our findings imply that glycyrrhizin is a potential efficient adjuvant therapeutic for PMO.

Inhibitory action of oxytocin on spontaneous contraction of rat distal colon by nitrergic mechanism: involvement of cyclic GMP and apamin-sensitive K+ channels.

AIM: The mechanisms underlying the inhibitory effects of oxytocin (OT) on colon tone are not totally understood. We explore the mechanisms of OT on spontaneous contractility in rat distal colon and identify the mediators involved in this action. METHODS: In rat distal colon strips, mechanical activity was analysed and the production of nitric oxide (NO) in tissue loaded with the fluorochrome DAF-FM was visualized by confocal microscopy. OT receptor (OTR) expression was determined by Western blotting and immunofluorescence. RESULTS: In rat distal colon, OT produced a concentration-dependent reduction in the spontaneous contraction, which was abolished by the OTR antagonist atosiban, the neural blocker tetrodotoxin and the inhibitor of neuronal nitric oxide synthase (nNOS) NPLA. The inhibitory effects of OT were not affected by propranolol, atropine, the nicotinic cholinoceptor blocker hexamethonium, the vasoactive intestinal peptide receptor antagonist VIPHyb, the P2 purinoceptor antagonist PPADS, the adenosine A1 receptors antagonist DPCPX and the prostacyclin receptor antagonist Ro1138452. The soluble guanylyl cyclase (sGC) inhibitor ODQ and the small conductance Ca2+ -activated K+ (Ca K+ ) channels blocker apamin significantly reduced the relaxation induced by OT, nicotine, sodium nitroprusside and the sGC activator BAY 41-2272. The neural release of NO elicited by OT was prevented by NPLA, tetrodotoxin and atosiban. The presence of the OTR and its co-localization with nNOS was detected by immunohistochemistry and Western blotting experiments. CONCLUSION: These results demonstrate the NO release from enteric neurones induced by activation of OTR mediates distal colon relaxation. sGC and small conductance Ca K+ channels are involved in this relaxation.

The application value of the detection of the level of tissue polypeptide antigen, ovarian cancer antigen X1, cathepsin L and CA125 on the diagnosis of epithelial ovarian cancer.

OBJECTIVE: We investigated the value of the joint detection of tissue polypeptide antigen (TPA), ovarian cancer antigen X1 (OVX1), cathepsin L (CTSL) and CA125 on the early diagnosis of epithelial ovarian carcinoma (EOC). PATIENTS AND METHODS: From October 2011 to February 2015, 84 cases of patients under surgical treatment of epithelial ovarian cancer, 98 cases of patients with benign epithelial ovarian tumor and 51 subjects in healthy control group were selected to detect the level of TPA, OVX1 and CTSL in serum from the Obstetrics and Gynecology Department of the First Affiliated Hospital of Liaoning Medical University. The clinical data of patients with ovarian tumor were collected and analyzed, and the levels of CA12 were measured. RESULTS: 3 indicators in the malignant group were significantly higher than those in the benign group and healthy control group (p < 0.05). The total positive rate and the positive rate of early detection of TPA on EOC were the highest, and the total positive rate of OVX1 was lower than that of CA125. The total positive rate and the positive rate of early detection of CA125+TPA on EOC were the highest. The positive rate of early detection and the total positive rate of the pairwise combined detection of the other index and CA125 on EOC were significantly higher than those of the single detection of CA125 (p < 0.05). The joint detection of CA125+ OVX1 and the single detection of CA125 were not statistically significant. However, the remaining differences were statistically significant (p < 0.05). CONCLUSIONS: The level of TPA, OVX1 and CTSL in serum was potential detection index, the joint detection of TPA and CA125 was the ideal combination, which took into account the total positive rate, the positive rate of early detection on EOC and the improved diagnostic rate of EOC.