Chelation-directed interface engineering of in-place self-cleaning membranes.

Water-energy sustainability will depend upon the rapid development of advanced pressure-driven separation membranes. Although energy-efficient, water-treatment membranes are constrained by ubiquitous fouling, which may be alleviated by engineering self-cleaning membrane interfaces. In this study, a metal-polyphenol network was designed to direct the armorization of catalytic nanofilms (ca. 18 nm) on inert polymeric membranes. The chelation-directed mineralized coating exhibits high polarity, superhydrophilicity, and ultralow adhesion to crude oil, enabling cyclable crude oil-in-water emulsion separation. The in-place flux recovery rate exceeded 99.9%, alleviating the need for traditional ex situ cleaning. The chelation-directed nanoarmored membrane exhibited 48-fold and 6.8-fold figures of merit for in-place self-cleaning regeneration compared to the control membrane and simple hydraulic cleaning, respectively. Precursor interaction mechanisms were identified by density functional theory calculations. Chelation-directed armorization offers promise for sustainable applications in catalysis, biomedicine, environmental remediation, and beyond.

Efficacy and safety of intratonsillar immunotherapy for allergic rhinitis: A randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: A lower adherence rate existed in patients receiving allergen-specific immunotherapy due to its lengthy period and adverse effects even though it is the only curative treatment for IgE-mediated allergies. Therefore, exploring innovative allergen-specific immunotherapy routes is necessary. OBJECTIVE: To explore the efficacy and safety of the intratonsillar injection of house dust mite (HDM) extract in patients with HDM-induced allergic rhinitis (AR). METHODS: A randomized, double-blind, placebo-controlled clinical trial was conducted. A total of 80 patients with HDM-induced AR were randomized to receive 6 intratonsillar injections with HDM extract or placebo in 3 months. The total nasal symptom score (TNSS), visual analogue scale of nasal symptoms, combined symptom and medication score, mini rhinoconjunctivitis quality of life questionnaire, and serum allergen-specific IgG4 to Dermatophagoides pteronyssinus were all monitored at baseline and 3 months, 6 months, and 12 months after the treatment was finished. The intent-to-treat and per-protocol set (PPS) are both analyzed. RESULTS: The primary end points TNSS and ΔTNSS were improved significantly at 3 months after the patients with AR finished a 3-month 6-injection intratonsillar immunotherapy compared with those in the placebo treatment in both intent-to-treat and PPS. Results of visual analogue scale, combined symptom and medication score, and mini rhinoconjunctivitis quality of life questionnaire were also improved significantly at 3 months after the treatment in PPS. However, the improvement effect of intratonsillar immunotherapy at 6 and 12 months was limited and uncertain based on the data. The increase of serum Der p IgG4 in the active group was significantly higher than that in the placebo group at 3, 6, and 12 months after the treatment was finished. Adverse events were monitored, and no systemic adverse reactions were observed. CONCLUSION: The clinical trial revealed that intratonsillar injection with HDM extract was safe and effective in patients with AR. Optimizing the protocol and allergen formulations is expected to increase and maintain the efficacy of this novel approach. TRIAL REGISTRATION: https://www.chictr.org.cn/index.html, identifier: ChiCTR-TRC-13003600.

Effects of eutrophication on the horizontal transfer of antibiotic resistance genes in microalgal-bacterial symbiotic systems.

Overloading of nutrients such as nitrogen causes eutrophication of freshwater bodies. The spread of antibiotic resistance genes (ARGs) poses a threat to ecosystems. However, studies on the enrichment and spread of ARGs from increased nitrogen loading in algal-bacterial symbiotic systems are limited. In this study, the transfer of extracellular kanamycin resistance (KR) genes from large (RP4) small (pEASY-T1) plasmids into the intracellular and extracellular DNA (iDNA, eDNA) of the inter-algal environment of Chlorella pyrenoidosa was investigated, along with the community structure of free-living (FL) and particle-attached (PA) bacteria under different nitrogen source concentrations (0-2.5 g/L KNO3). The results showed that KR gene abundance in the eDNA adsorbed on solid particles (D-eDNA) increased initially and then decreased with increasing nitrogen concentration, while the opposite was true for the rest of the free eDNA (E-eDNA). Medium nitrogen concentrations promoted the transfer of extracellular KR genes into the iDNA attached to algal microorganisms (A-iDNA), eDNA attached to algae (B-eDNA), and the iDNA of free microorganisms (C-iDNA); high nitrogen contributed to the transfer of KR genes into C-iDNA. The highest percentage of KR genes was found in B-eDNA with RP4 plasmid treatment (66.2%) and in C-iDNA with pEASY-T1 plasmid treatment (86.88%). In addition, dissolved oxygen (DO) significantly affected the bacterial PA and FL community compositions. Nephelometric turbidity units (NTU) reflected the abundance of ARGs in algae. Proteobacteria, Cyanobacteria, Bacteroidota, and Actinobacteriota were the main potential hosts of ARGs. These findings provide new insights into the distribution and dispersal of ARGs in the phytoplankton inter-algal environment.

Identification of AGO2 and PLEC genes polymorphisms in Hu sheep and their relationship with body size traits.

The body size traits are major traits in livestock, which intuitively displays the development of the animal's bones and muscles. This study used PCR amplification, Sanger sequencing, KASPar genotyping, and quantitative real-time reverse transcription PCR (qRT-PCR) to analyze the Single-nucleotide polymorphism and expression characteristics of Argonaute RISC catalytic component 2 (AGO2) and Plectin (PLEC) genes in Hu sheep. Two intron mutations were found in Hu sheep, which were AGO2 g.51700 A > C and PLEC g.23157 C > T, respectively. Through association analysis of two mutation sites and body size traits, it was found that AGO2 g.51700 A > C mainly affects the chest and cannon circumference of Hu sheep of while PLEC g.23157 C mainly affects body height and body length. The combined genotypes of AGO2 and PLEC genes with body size traits showed SNPs at the AGO2 g.51700 A > C and PLEC g.23157 C > T loci significantly improved the body size traits of Hu sheep. In addition, the AGO2 gene has the highest expression levels in the heart, rumen, and tail fat, and the PLEC gene is highly expressed in the heart. These two loci can provide new research ideas for improving the body size traits of Hu sheep.

Identification of the FGB gene polymorphism and analysis of its association with fat deposition traits in Hu sheep.

As a crucial economic trait, fat deposition is directly related to carcass quality and feed efficiency in sheep. The purpose of this study was to investigate the polymorphisms of the FGB gene related to fat deposition and detect the expression features of the FGB gene in different adipose tissues of sheep by using Sanger sequencing, MassARRAY® SNP technique, and quantitative real-time PCR (qRT-PCR). Results showed that in the intron region of the FGB gene, a SNP g. 3378953 A > T has been identified, and significant association was found between perirenal fat weight, perirenal fat relative weight, mesenteric fat weight, and mesenteric fat relative weight (P < 0.05). Moreover, qRT-PCR analysis showed that FGB was expressed in all three adipose tissues, and FGB gene expression level in the AA genotype was significantly lower than that in the AT or TT genotypes (P < 0.05). Therefore, the FGB gene can be used as a candidate gene to reduce fat deposition in Hu sheep breeding, and the selection of the AA genotype in Hu sheep in production practice is more conducive to improving production efficiency.

Polymorphism in IGFALS gene and its association with scrotal circumference in Hu lambs.

Scrotal circumference is an important reproductive index of breeding rams, which has a high genetic correlation with ejaculation volume and semen quality. In this study, the scrotal circumference of 1353 male Hu sheep at different stages of development was measured and descriptive statistical analysis was performed. The results showed that the coefficient of variation of scrotal circumference at each stage was greater than 10%, and its heritability were moderately to high, ranging from 0.318 to 0.719. We used PCR amplification and Sanger sequencing to scan the polymorphisms of the IGFALS gene, and performed association analysis with the circumference of the scrotum at different stages. We identified a synonymous mutation g.918 G > C in exon 1 of the IGFALS gene, and this mutation was significantly associated with scrotal circumference at 100, 120, 140, 160 and 180 days (p < 0.05). Therefore, IGFALS gene polymorphism can be used as a molecular marker affecting scrotal circumference of Hu sheep, which can provide a reference for future molecular marker-assisted selection of scrotal circumference in sheep.

Detection of single nucleotide polymorphism in HTR4 and its relationship with growth traits in sheep.

In this study, a single nucleotide polymorphism of HTR4 (hydroxytryptamine receptor 4) was detected using DNA sequencing and KASPar (Kompetitive Allele-Specific PCR) technique with the aim of analyzing its effect on growth traits in 1102 sheep. A synonymous mutation g.101220 C > T located on the fifth intron of the ovis HTR4 gene was detected, and association analysis showed that this mutation was significantly associated with growth traits in sheep (p ＜.05), with TT genotypes having significantly lower body weight, height, length and chest circumference than TC and CC genotypes. It showed that the polymorphism of this locus was significantly associated with growth traits in sheep. In addition, qRT-PCR results showed that HTR4 was expressed in different tissues of sheep. It is highly expressed in the liver, spleen and duodenum. As important metabolic, immune and digestive absorption organs in animals, the above tissues can regulate the excitability of intestinal smooth muscle by participating in the body metabolism and nutrient metabolism of sheep, so that sheep can show better growth characteristics. In conclusion, the polymorphic locus identified in HTR4 gene can be used as candidate molecular marker in sheep breeding.

Identification of polymorphic loci in OSMR and GHR genes and analysis of their association with growth traits in sheep.

The aim of this study was to analyze the effect of OSMR and GHR genes polymorphisms on growth traits in sheep. The single nucleotide polymorphisms of sheep OSMR and GHR genes were identified by DNA sequencing technology. A total of two intronic mutations g.2443 T > C and g.170196 A > G were identified in OSMR and GHR, respectively. Correlation analysis was carried out between the obtained genotypes and the growth traits of sheep. The results showed that at the OSMR g.2443 T > C locus, the body weight, chest circumference and cannon circumference of the TT genotype sheep were significantly higher than those of the CC genotype sheep (p < .05). At the GHR g.170196 A > G locus, the body weight, body length, chest circumference and cannon circumference of the AA genotype sheep were significantly higher than those of the AG genotype and GG genotype sheep (p < .05). Moreover, the body weight of sheep of combination TTOSMR/AAGHR genotype was significantly higher than that of other combination genotypes (p < .05). Therefore, we believe that the polymorphic sites identified in the OSMR and GHR genes can be used as candidate molecular markers for breeding good traits in sheep.

Polymorphism and expression level of the FADS3 gene and associated with the growth traits in Hu sheep.

Growth traits are the economically important traits of sheep, and screening for genes related to growth and development is helpful for the genetic improvement of ovine growth traits. The fatty acid desaturase 3 (FADS3) is one of the important genes affecting the synthesis and accumulation of polyunsaturated fatty acids in animals. In this study, the expression levels of the FADS3 gene and polymorphism of the FADS3 gene associated with growth traits in Hu sheep were detected using quantitative real-time PCR (qRT-PCR), Sanger sequencing, and KAspar assay. The result showed that the expression levels of the FADS3 gene were widely expressed in all tissues, and the expression level of FADS3 in the lung was significantly higher than in other tissues (p < .05). Then, the polymorphism locus g. 2918 A > C was detected in intron 2 of the FADS3 gene, and associated analysis showed that the mutation in the FADS3 gene was associated significantly with growth traits (including body weight, body height, body length, and chest circumference, p < .05). Therefore, individuals with AA genotype showed significantly better growth traits than those with CC genotype, and FADS3 gene could be a candidate gene for improving growth traits in Hu sheep.

Identification and characterization of circular RNAs in association with the feed efficiency in Hu lambs.

BACKGROUND: Circular RNA (circRNA), as a new members of noncoding RNA family, have vital functions in many biological processes by as microRNA sponges or competing endogenous RNAs (ceRNAs). However, little has been reported about the genetic mechanism of circRNAs regulation of feed efficiency in sheep. RESULTS: This study aimed to explore the expression of circRNAs in the liver of Hu sheep with High-RFI (High residual feed intake) and Low-RFI (Low residual feed intake) using transcriptome sequencing. A total of 20,729 circRNAs were identified in two groups, in which 219 circRNAs were found as significantly differentially expressed. Several circRNAs were validated by using RT-PCR, sanger sequencing and RT-qPCR methods. These results demonstrated that the RNA-seq result and expression level of circRNAs identified are reliable. Subsequently, GO and KEGG enrichment analysis of the parental genes of the differentially expressed (DE) circRNAs were mainly involved in immunity response and metabolic process. Finally, the ceRNA regulatory networks analysis showed that the target binding sites for miRNA such as novel_41, novel_115, novel_171 and oar-miR-485-3p in the identified DE cirRNAs. Importantly, two metabolic (SHISA3 and PLEKHH2) and four (RTP4, CD274, OAS1, and RFC3) immune-related target mRNAs were identified from 4 miRNAs. Association analysis showed that the polymorphism (RTP4 c.399 A > G) in the target gene RTP4 were significantly associated with RFI (P < 0.05). CONCLUSIONS: Analysis of sequencing data showed some candidate ceRNAs that may play key roles in the feed efficiency in sheep by regulating animal immune and metabolic. These results provide the basis data for further study of the biological functions of circRNAs in regulating sheep feed efficiency.

Novel polymorphism at KLF15 gene and its association with growth traits in Hu sheep.

Growth traits are important economic characteristics of livestock and poultry. In the present study, the expression features of KLF15 and the relationship between KLF15 gene polymorphisms and growth traits in Hu sheep were investigated by using real-time quantitative PCR technology (qPCR), Sanger sequencing, and Kaspar genotyping technology. The qPCR results showed that the KLF15 gene is expressed widely in the tested tissues of Hu sheep, and the expression level of the KLF15 gene in the heart and the muscle was significantly higher than in other tissues (p < 0.05). Missense mutation c.62565119 A > G was found in KLF15, and an association analysis showed that it was correlated with the growth traits (body weight, body height, and body length) of Hu sheep (p < 0.05). The body weight, body height, and body length of the sheep carrying the AA genotype were remarkably higher than those of the GG and AG genotypes (p < 0.05). These results showed that novel polymorphisms at the KLF15 gene can be used as a genetic marker of growth traits of Hu sheep.

Polymorphism in ovine ADCY8 gene and its association with residual feed intake in Hu sheep.

Feed efficiency makes up a large part of sheep production, which also has a crucial impact on the economic benefits of producers. This study explores the polymorphism of Adenylyl cyclase 8 gene associated with feed efficiency and detects the expression characteristics of ADCY8 in ten tissues of Hu sheep. The polymorphism of ADCY8 was recognized by using PCR amplification and Sanger sequencing, KASPar technology was used for genotyping subsequently, and the relationship between SNP and RFI is also studied. The results indicated that an intronic mutation g.24799148 C > T (rs 423395741) was identified in ADCY8, and association analysis showed that the SNP g.24799148 C > T (rs 423395741) was significantly associated with RFI at 100-120, 100-140, 100-160, and 100-180 days (p < 0.05). The quantitative real-time PCR (qRT-PCR) result showed that ADCY8 was expressed in ten tissues, and the expression of ADCY8 gene in rumen tissue was significantly higher than in the other tested tissues. Therefore, these results indicated that the ADCY8 mutation locus may be used as a candidate molecular marker for evaluating the feed efficiency of Hu sheep.

Polygalaxanthone III, an Active Ingredient in Polygala japonica Houtt., Repaired Malassezia-Stimulated Skin Injury via STAT3 Phosphorylated Activation.

Malassezia is a genus of commensal and lipid-dependent yeasts in human skin which also have a pathogenic lifestyle associated with several common skin disorders such as atopic dermatitis and eczema. Symptoms include red, itchy, and inflamed skin. We studied the growth characteristics and biochemical analyses of M. furfur which showed that the protein contents were greater in extracts taken at 24 h. These were then used to infect C57BL/6 mice, resulting in skin rupture. Polygalaxanthone III (POL), a more effective anti-inflammatory ingredient in Polygala japonica Houtt., was applied externally to the ulceration and successfully healed the wounds quickly. POL could not inhibit Malassezia activity as tested by the inhibition zone test, but affected the formation of lipid droplets in HaCaT cells. The wound-healing molecular mechanisms may be involved in the STAT3 pathway according to the Western blot results of skin tissues. Malassezia's role in skin health is far from certain, and there is no clear solution, so understanding the development of Malassezia-associated skin diseases in general and seeking solutions are very important.

Cell cytoskeleton and proliferation study for the RANKL-induced RAW264.7 differentiation.

Although document studies (including ours) have been reported the achieved in vitro osteoclastic cellular model establishment from the RAW264.7 cell lineage, there was no study directly reported that American Type Culture Collection (ATCC) cell bank has various RAW264.7 cell lineages. Besides that, for our knowledge there was only one study compared the two different RAW264.7TIB-71 and RAW264.7CRL-2278 cell lineages for their osteoclastic differentiation, and they concluded that the RAW264.7CRL-2278 demonstrated to generate much osteoclast than RAW264.7TIB-71 . However, on the contrary to their results we noticed the fusion of RAW264.7TIB-71 in our previous studies was much compromising. Therefore, we try to explore the two cell lineages for their properties in osteoclastic differentiation with an in-depth cellular cytoskeletal study. Our current study has showed that comparing to the RAW264.7CRL-2278 , RAW264.7TIB-71 demonstrated a much higher efficacies for RANKL-stimulated osteoclastic differentiation. Besides that, in our depth cytoskeletal studies, we found that the RANKL-induced RAW264.7TIB-71 cells could finally differentiate into mature osteoclasts. However, regardless the various pre-treatment conditions, there was no mature osteoclast formed in RANKL-induced RAW264.7CRL-2278 cell lineage.

Polygalaxanthone III downregulates inflammation in the lipopolysaccharide-stimulated RAW264.7 macrophages: A quantibody array analysis.

Polygala japonica Houtt. (PJ), a member of the Polygala L. family that is suggested to exhibit detoxification properties in traditional Chinese medicine, is often used to treat upper respiratory tract infections. The anti-inflammatory effects of four main components of PJ (POL, PS-XLIX, PS-E, and PS-F) were examined using the LPS(0.3 µg·mL-1)-stimulated RAW264.7 macrophage model. The levels of NO, ROS, and iNOS were examined to analyze the anti-inflammatory activity of POL. Additionally, the levels of extracellular inflammation-related cytokines and chemokines were measured using quantibody array. The KEGG pathway analysis was performed to examine the anti-inflammatory mechanism of POL. The levels of NO in the POL-pretreated group were significantly downregulated when compared with those in the PS-E-pretreated, PS-F-pretreated, and PS-XLIX-pretreated groups. POL significantly inhibited the changes of iNOS, ROS, and inflammatory factors caused by LPS stimulation (p < 0.001). The expression levels of IL21 and GM-CSF were examined using qPCR, while those of JAK-STAT signaling pathway-related proteins in the LPS-stimulated RAW264.7 macrophages were analyzed using western blotting. POL significantly downregulated the expression of IL-21 and GM-CSF. The anti-inflammatory mechanism of POL is mediated through the JAK-STAT pathway. Thus, this study demonstrated that POL is an anti-inflammatory component of PJ and elucidated its mechanism.

Integrin-associated molecules and signalling cross talking in osteoclast cytoskeleton regulation.

In the ageing skeleton, the balance of bone reconstruction could commonly be broken by the increasing of bone resorption and decreasing of bone formation. Consequently, the bone resorption gradually occupies a dominant status. During this imbalance process, osteoclast is unique cell linage act the bone resorptive biological activity, which is a highly differentiated ultimate cell derived from monocyte/macrophage. The erosive function of osteoclasts is that they have to adhere the bone matrix and migrate along it, in which adhesive cytoskeleton recombination of osteoclast is essential. In that, the podosome is a membrane binding microdomain organelle, based on dynamic actin, which forms a cytoskeleton superstructure connected with the plasma membrane. Otherwise, as the main adhesive protein, integrin regulates the formation of podosome and cytoskeleton, which collaborates with the various molecules including: c-Cbl, p130Cas , c-Src and Pyk2, through several signalling cascades cross talking, including: M-CSF and RANKL. In our current study, we discuss the role of integrin and associated molecules in osteoclastogenesis cytoskeletal, especially podosomes, regulation and relevant signalling cascades cross talking.

Blockade of IL-6 alleviates bone loss induced by modeled microgravity in mice.

This study investigated the effects of blockade of IL-6 on bone loss induced by modeled microgravity (MG). Adult male mice were exposed to hind-limb suspension (HLS) and treated with IL-6-neutralizing antibody (IL-6 nAb) for 4 weeks. HLS in mice led to upregulation of IL-6 expression in both sera and femurs. IL-6 nAb treatment in HLS mice significantly alleviated bone loss, evidenced by increased bone mineral density of whole tibia, trabecular thickness and number, bone volume fraction of proximal tibiae, and ultimate load and stiffness of femoral diaphysis. IL-6 nAb treatment in HLS mice significantly enhanced levels of osteocalcin in sera and reduced levels of deoxypyridinoline. In MC3T3-E1 cells exposed to MG in vitro, IL-6 nAb treatment increased mRNA expression and activity of alkaline phosphatase, mRNA expression of osteopontin and runt-related transcription factor 2, and protein levels of osteoprotegerin and decreased protein levels of receptor activator of the NF-κB ligand. In RAW254.7 cells exposed to MG, IL-6 nAb treatment downregulated mRNA expression of cathepsin K and tartrate-resistant acid phosphatase (TRAP) and reduced numbers of TRAP-positive multinucleated osteoclasts. In conclusion, blockade of IL-6 alleviated the bone loss induced by MG.

Dilation of the cystic duct confluence in laparoscopic common bile duct exploration and stone extraction in patients with secondary choledocholithiasis.

BACKGROUND: Many options exist for the management of cholelithiasis and secondary choledocholithiasis. Among them, laparoscopic common bile duct exploration (LCBDE) with choledocotomy followed by laparoscopic cholecystectomy has gained popularity. However, efforts should be made to ensure minimally invasive or noninvasive management of the common bile duct (CBD). The purpose of this study was to explore the clinical experience of non-invasive surgical modality, i.e., laparoscopic transcystic dilation of the cystic duct confluence in CBD exploration (LTD-CBDE), including feasibility, safety, adverse events, and incidence. METHODS: In this retrospective analysis, 68 patients were offered the LTD-CBDE technique from December 2015 to April 2018 based on patient's own intention. During the surgery, the cystic duct confluence was dilated with separation forceps and/or a columnar dilation balloon. Subsequently, CBD exploration and stone extraction were performed with a choledochoscope. The entrance of the CBD was covered with a cystic duct stump wall and was subjected to primary closure at the end of surgery. RESULTS: Forty-nine females and 19 males with cholelithiasis and secondary choledocholithiasis were included. The mean age was 53 years old (18 to 72 year). Of these patients, 62 (91.2%) were successfully treated with the LTD-CBDE technique, and bile leakage was observed in 3 patients (4.4%). The mean operation time was 106 min, and the mean hospital stay was 5.9 days. Among the other 6 patients, 3 were converted to open cholecystectomy due to severe fibrosis, unclear anatomical structure at Calot's triangle (n = 2) or Mirizze syndrome (n = 1); LCBDE was performed in 3 patients due to cystic duct atresia (n = 2) and low level of flow from the gallbladder duct into the CBD (n = 1). These patients had a smooth postoperative course. In total, 43/68 of the patients presented no radiological evidence of retained CBD stones at the postoperative follow-up (40 patients treated with LTD-CBDE) 1 year later. CONCLUSIONS: The current work suggests that LTD-CBDE for the management of cholelithiasis and secondary choledocholithiasis is a feasible, safe and effective technique with a low complication rate. LTD-CBDE offers another alternative for surgeons to treat patients in similar scenarios. However, additional randomized, controlled studies are needed to demonstrate its efficacy, safety, and impact on CBD stenosis.

Evaluation of efficacy on RANKL induced osteoclast from RAW264.7 cells.

Established RAW264.7 cell lines for osteoclastic differentiation has been widely engaged in bone homeostasis research, however, the efficacy of RANKL independently stimulating has rarely been defined, because protocols were usually developed and modified by various laboratories. Otherwise, problematic issues are also lie in the cell's seeding density, RANKL stimulating time point, and distinguishing osteoclastogenesis ability of RANKL-treated RAW264.7 cells. Therefore, in the current study, we examined the efficacy of various concentrations of RANKL-treated RAW264.7 for its osteoclastic differentiation with or without pretreated other costimulators such as: LPS and/or M-CSF. The oteoclastogenesis ability of RANKL-treated RAW264.7 cells was demonstrated by bone resorption pit, F-actin, and osteoclastogenesis specific marker studies. Besides that, through tartrate-resistant acid phosphatase (TRAP) staining, we clarified to start the treatment with 30 ng/ml RANKL at 12 hr after seeded RAW264.7 with the density of 6.25 × 10 3 cells/cm 2 manifested an significantly increased number of multinucleated osteoclastic cells. Overall, our results establishing an optimal method for RANKL independently inducing RAW 264.7 cell osteoclastic differentiation, which could efficiently generate osteoclasts in vitro for significant advances in our understanding of bone biology.

Treatment with hydrogen sulfide donor attenuates bone loss induced by modeled microgravity.

The present study was undertaken to explore the therapeutic potential of hydrogen sulfide against bone loss induced by modeled microgravity. Hindlimb suspension (HLS) and rotary wall vessel bioreactor were applied to model microgravity in vivo and in vitro, respectively. Treatment of rats with GYY4137 (a water soluble donor of hydrogen sulfide, 25 mg/kg per day, i.p.) attenuated HLS-induced reduction of bone mineral density in tibiae, and preserved bone structure in tibiae and mechanical strength in femurs. In HLS group, GYY4137 treatment significantly increased levels of osteocalcin in sera. Interestingly, treatment of HLS rats with GYY4137 enhanced osteoblast surface, but had no significant effect on osteoclast surface of proximal tibiae. In MC3T3-E1 cells exposed to modeled microgravity, GYY4137 stimulated transcriptional levels of runt-related transcription factor 2 and enhanced osteoblastic differentiation, as evidenced by increased mRNA expression and activity of alkaline phosphatase. HLS in rats led to enhanced levels of interleukin 6 in sera, skeletal muscle, and tibiae, which could be attenuated by GYY4137 treatment. Our study showed that GYY4137 preserved bone structure in rats exposed to HLS and promoted osteoblastic differentiation in MC3T3-E1 cells under modeled microgravity.