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Chemerin, a chemokine, plays important roles in immune responses, inflammation, adipogenesis, and carbohydrate metabolism. Our recent research has shown that chemerin has an inhibitory effect on hormone secretion from the testis and ovary. However, whether G protein-coupled receptor 1 (GPR1), the active receptor for chemerin, regulates steroidogenesis and luteolysis in the corpus luteum is still unknown. In this study, we established a pregnant mare serum gonadotropin-human chorionic gonadotropin (PMSG-hCG) superovulation model, a prostaglandin F2α (PGF2α) luteolysis model, and follicle and corpus luteum culture models to analyze the role of chemerin signaling through GPR1 in the synthesis and secretion of gonadal hormones during follicular/luteal development and luteolysis. Our results, for the first time, show that chemerin and GPR1 are both differentially expressed in the ovary over the course of the estrous cycle, with highest levels in estrus and metestrus. GPR1 has been localized to granulosa cells, cumulus cells, and the corpus luteum by immunohistochemistry (IHC). In vitro, we found that chemerin suppresses hCG-induced progesterone production in cultured follicle and corpus luteum and that this effect is attenuated significantly by anti- GPR1 MAB treatment. Furthermore, when the phosphoinositide 3-kinase (PI3K) pathway was blocked, the attenuating effect of GPR1 MAB was abrogated. Interestingly, PGF2α induces luteolysis through activation of caspase-3, leading to a reduction in progesterone secretion. Treatment with GPR1 MAB blocked the PGF2α effect on caspase-3 expression and progesterone secretion. This study indicates that chemerin/GPR1 signaling directly or indirectly regulates progesterone synthesis and secretion during the processes of follicular development, corpus luteum formation, and PGF2α-induced luteolysis. [ABSTRACT FROM AUTHOR]

Continued production of wear debris affects both initial osseointegration and subsequent bone remodeling of total joint replacements (TJRs). However, continuous delivery of clinically relevant particles using a viable, cost effective, quantitative animal model to simulate the scenario in humans has been a challenge for orthopedic researchers. In this study, we successfully infused blue‐dyed polystyrene particles, similar in size to wear debris in humans, to the intramedullary space of the mouse femur for 4 weeks using an osmotic pump. Approximately 40% of the original particle load (85 μL) was delivered into the intramedullary space, an estimate of 3 × 109 particles. The visible blue dye carried by the particles confirmed the delivery. This model demonstrated that continuous infusion of particles to the murine bone‐implant interface is possible. In vivo biological processes associated using wear debris particles can be studied using this new animal model. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [ABSTRACT FROM AUTHOR]

Background: This work aimed to evaluate the effects of genistein treatment in Collagen Induced Arthritis (CIA) mouse model., Methods: CIA was elicited in DBA/1 Mice by an intradermal injection of 100 μL of an emulsion of bovine type II collagen (CII) in isovolumic incomplete Freund's adjuvant (IFA) at the base of the tail. Twenty-one days later, a second injection of CII in IFA was administered at the base of the tail. After the symptoms of arthritis showed in mouse model, we divided animals into two groups according to their clinical symptom scores. The treatment group was intraperitoneally injected daily with genistein (based on the pre-experiment data and literature reported, 5 mg/kg dose was selected and tested) for 12 days, while the control group was injected with phosphate buffered saline. Inflammatory cytokines titer, radiological, and histological observations were completed at different time's points after treatment. CT analysis was conducted 3 months after the treatment to observe the articular structures. Immunohistochemical analysis was performed to investigate the expression and distribution of VEGF in joint tissues., Results: Genistein suppressed the expressions of IL-1β, IL-6 and TNF-α in the serum. Radiological results showed that bone degradation was inhibited by the treatment. Moreover, hematoxylin and eosin staining showed that the degree of inflammation was relieved. In the cartilage area, TRAP stain-positive cells were detected, which was notably reduced in the treatment group compared to the control group. Micro-CT 3D images clearly exhibited that the joint adhered and structures destroyed in the control group with less destruction in the treatment group. Furthermore, genistein suppressed VEGF expression, and blocked angiogenesis in the synovial tissue., Conclusion: Our work provides further data regarding the effects of genistein as a potential treatment drug for RA, as well as the role of genistein in the anti-inflammatory pathway in RA therapy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

A Gram-positive, halophilic bacterium was isolated from a sediment sample from Ai-Ding salt lake in China. The isolate, designated strain 17-5(T), grew at salinities of 8-33 % (w/v) NaCl (optimally at 12 %, w/v). The genomic DNA G+C content of strain 17-5(T) was 48.1 mol%. The predominant isoprenoid quinone was MK-7(H(2)) and the cell-wall peptidoglycan contained meso-diaminopimelic acid. The major polar lipids were diphosphatidylglycerol and an unidentified glycolipid. The major cellular fatty acids were anteiso-C(15 : 0), anteiso-C(17 : 0), iso-C(16 : 0) and C(16 : 0). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 17-5(T) was a member of the genus Bacillus, being most closely related to Bacillus qingdaonensis JCM 14087(T) (96.0 % sequence similarity) and Bacillus salarius DSM 16461(T) (95.6 %). The levels of 16S rRNA gene sequence similarity with respect to other Bacillus species were less than 91.7 %. Comparative analysis of the 16S rRNA gene sequence data, chemotaxonomy and phenotypic features of the novel isolate and related species of Bacillus indicated that strain 17-5(T) represents a novel species within the genus Bacillus, for which the name Bacillus aidingensis sp. nov. is proposed. The type strain is 17-5(T) (=CGMCC 1.3227(T)=DSM 18341(T)).