Hypothalamic and ovarian transcriptome profiling reveals potential candidate genes in low and high egg production of white Muscovy ducks (Cairina moschata).

In China, the low egg production rate is a major challenge to Muscovy duck farmers. Hypothalamus and ovary play essential role in egg production of birds. However, there are little or no reports from these tissues to identify potential candidate genes responsible for egg production in White Muscovy ducks. A total of 1,537 laying ducks were raised; the egg production traits which include age at first egg (days), number of eggs at 300 d, and number of eggs at 59 wk were recorded. Moreover, 4 lowest (LP) and 4 highest producing (HP) were selected at 59 wk of age, respectively. To understand the mechanism of egg laying regulation, we sequenced the hypothalamus and ovary transcriptome profiles in LP and HP using RNA-Seq. The results showed that the number of eggs at 300 d and number of eggs at 59 wk in the HP were significantly more (P < 0.001) than the LP ducks. In total, 106.98G clean bases were generated from 16 libraries with an average of 6.68G clean bases for each library. Further analysis showed 569 and 2,259 differentially expressed genes (DEGs) were identified in the hypothalamus and ovary between LP and HP, respectively. The KEGG pathway enrichment analysis revealed 114 and 139 pathways in the hypothalamus and ovary, respectively which includes Calcium signaling pathway, ECM-receptor interaction, Focal adhesion, MAPK signaling pathway, Apoptosis and Apelin signaling pathways that are involved in egg production. Based on the GO terms and KEGG pathways results, 10 potential candidate genes (P2RX1, LPAR2, ADORA1, FN1, AKT3, ADCY5, ADCY8, MAP3K8, PXN, and PTTG1) were identified to be responsible for egg production. Further, protein-protein interaction was analyzed to show the relationship between these candidate genes. Therefore, this study provides useful information on transcriptome of hypothalamus and ovary of LP and HP Muscovy ducks.

Kindlin-1 is a key protein in hyperbaric oxygen therapy for the treatment of neuropathic pain.

Background: Hyperbaric oxygen therapy is increasingly used in adjuvant therapies to treat neuropathic pain. However, the specific targets of hyperbaric oxygen treatment in neuropathic pain remain unclear. Recently, we found that hyperbaric oxygen therapy produces an antinociceptive response via the kindlin-1/wnt-10a signaling pathway in a chronic pain injury model in rats. Methods: The rats received an intraperitoneal injection of AAV-FERMT1 or an adeno-associated virus control vector 20 days before the chronic constriction injury operation. During five consecutive days of hyperbaric oxygen treatment, mechanical withdrawal threshold and thermal withdrawal latency tests were performed. Then, kindlin-1 expression was examined by real-time polymerase chain reaction and Western blot analysis. Meanwhile, the activation of glial cells and the production of TNF-α, IL-1ß, and fractalkine were also determined. Results: Our findings demonstrated that hyperbaric oxygen therapy inhibited the chronic constriction injury­induced increase in kindlin-1 expression. Furthermore, overexpression of kindlin-1 reversed the antinociceptive effects of hyperbaric oxygen therapy. The observed hyperbaric oxygen­induced reductions in glial cell activation and neuroinflammation, as indicated by the production of TNF-α, IL-1ß, and fractalkine, were also prominently diminished in the group with kindlin-1 overexpression. Conclusions: Our findings demonstrate that kindlin-1 is a key protein in the action of hyperbaric oxygen therapy in the treatment of neuropathic pain. Indeed, interference with kindlin-1 may be a drug target for reducing the neuroinflammatory responses of the glial population in neuropathic pain.

Hyperbaric oxygen attenuates neuropathic pain and reverses inflammatory signaling likely via the Kindlin-1/Wnt-10a signaling pathway in the chronic pain injury model in rats.

BACKGROUND: Hyperbaric oxygen (HBO) therapy is proven to attenuate neuropathic pain in rodents. The goal of the present study was to determine the potential involvement of the Kindlin-1/Wnt-10a signaling pathway during astrocyte activation and inflammation in a rodent model of neuropathic pain. METHODS: Rats were assigned into sham operation, chronic constriction injury (CCI), and CCI + HBO treatment groups. Neuropathic pain developed in rats following CCI of the sciatic nerve. Rats in the CCI + HBO group received HBO treatment for five consecutive days beginning on postoperative day 1. The mechanical withdrawal threshold (MWT) and the thermal withdrawal latency (TWL) tests were performed to determine mechanical and heat hypersensitivity of animals, respectively. Kindlin-1, Wnt-10a and ß-catenin protein expression was examined by immunohistochemistry and Western blot analysis. Expression of tumor necrosis factor (TNF)-α was also determined by ELISA. RESULTS: Our findings demonstrated that HBO treatment significantly suppressed mechanical and thermal hypersensitivity in the CCI neuropathic pain model in rats. HBO therapy significantly reversed the up-regulation of Kindlin-1 in dorsal root ganglia (DRG), spinal cord, and hippocampus of CCI rats. CCI-induced astrocyte activation and increased levels of TNF-α were efficiently reversed by HBO (P < 0.05 vs. CCI). HBO also reversed Wnt-10a up-regulation induced by CCI in the DRG, spinal cord, and hippocampus (P < 0.05 vs. CCI). CONCLUSIONS: Our findings demonstrate that HBO attenuated CCI-induced rat neuropathic pain and inflammatory responses, possibly through regulation of the Kindlin-1/Wnt-10a signaling pathway.

Hyperbaric Oxygen Pretreatment Improves Cognition and Reduces Hippocampal Damage Via p38 Mitogen-Activated Protein Kinase in a Rat Model.

PURPOSE: To investigate the effects of hyperbaric oxygen (HBO) pretreatment on cognitive decline and neuronal damage in an Alzheimer's disease (AD) rat model. MATERIALS AND METHODS: Rats were divided into three groups: normal saline (NS), AD, and HBO+AD. In the AD group, amyloid ß peptide (Aß)1₋40 was injected into the hippocampal CA1 region of the brain. NS rats received NS injection. In the HBO+AD group, rats received 5 days of daily HBO therapy following Aß1₋40 injection. Learning and memory capabilities were examined using the Morris water maze task. Neuronal damage and astrocyte activation were evaluated by hematoxylin-eosin staining and immunohistochemistry, respectively. Dendritic spine density was determined by Golgi-Cox staining. Tumor necrosis factor-α, interleukin-1ß, and interleukin-10 production was assessed by enzyme-linked immunosorbent assay. Neuron apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling. Protein expression was examined by western blotting. RESULTS: Learning and memory dysfunction was ameliorated in the HBO+AD group, as shown by significantly lower swimming distances and escape latency, compared to the AD group. Lower rates of neuronal damage, astrocyte activation, dendritic spine loss, and hippocampal neuron apoptosis were seen in the HBO+AD than in the AD group. A lower rate of hippocampal p38 mitogen-activated protein kinase (MAPK) phosphorylation was observed in the HBO+AD than in the AD group. CONCLUSION: HBO pretreatment improves cognition and reduces hippocampal damage via p38 MAPK in AD rats.

The effects of ageing on the biomechanical properties of root dentine and fracture.

OBJECTIVES: Knowledge of the mechanical behaviour of root dentine can facilitate better understanding of spontaneous vertical root fracture (VRF), an age-related disease initiated mainly at the root apex. We tested the hypothesis that the biomechanical properties of root dentine change with ageing. METHODS: Sixteen human premolars were divided into "old" (17-30 years) and "young" (50-80 years) groups. The elastic modulus, nano-hardness, micro-hardness, elemental contents, tubular density/area of root dentine in cervical, middle and apical root regions were evaluated using atomic force microscopy-based nano-indentation, Knoop indentation, scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively. RESULTS: The apical dentine showed a lower nano-hardness, a lower elastic modulus, a lower calcium content, a lower calcium-to-phosphorus ratio and a smaller tubular density/area than the cervical dentine in both age groups, whereas spatial differences in micro-hardness were observed only in old roots. Compared with young dentine, old dentine showed a greater hardness, a higher elastic modulus, a greater mineral content and a smaller tubular size in the cervical portion, whereas the age-induced changes in tubular density were insignificant. Finite element analysis revealed that due to its higher elastic modulus, old apical dentine has a higher stress level than young dentine. CONCLUSIONS: The intrinsic material properties of root dentine have spatial variations, and they are altered by ageing. The higher stress level in old apical dentine may be one reason, if not the most important one, why spontaneous VRFs are more likely to occur in the elderly population.