Vitamin D receptor expression in human bone tissue and dose-dependent activation in resorbing osteoclasts

The effects of vitamin D on osteoblast mineralization are well documented. Reports of the effects of vitamin D on osteoclasts, however, are conflicting, showing both inhibition and stimulation. Finding that resorbing osteoclasts in human bone express vitamin D receptor （VDR）, we examined their response to different concentrations of 25-hydroxy vitamin D3 [25（OH）D3] （100 or 500 nmol·L^-1） and 1,25-dihydroxy vitamin D3 [1,25（OH）2D3] （0.1 or 0.5 nmol·L^-1） metabolites in cell cultures. Specifically, CD14＋ monocytes were cultured in charcoal-stripped serum in the presence of receptor activator of nuclear factor kappa-B ligand （RANKL） and macrophage colony-stimulating factor （M-CSF）. Tartrate-resistant acid phosphatase （TRAP） histochemical staining assays and dentine resorption analysis were used to identify the size and number of osteoclast cells, number of nuclei per cell and resorption activity. The expression of VDR was detected in human bone tissue （ex vivo） by immunohistochemistry and in vitro cell cultures by western blotting. Quantitative reverse transcription-PCR （qRT-PCR） was used to determine the level of expression of vitamin D-related genes in response to vitamin D metabolites. VDR-related genes during osteoclastogenesis, shown by qRT-PCR, was stimulated in response to 500 nmol·L^-1 of 25（OH）D3 and 0.1-0.5 nmol·L^-1 of 1,25（OH）2D3, upregulating cytochrome P450 family 27 subfamily B member I （CYP27B1） and cytochrome P450 family 24 subfamily A member I （CYP24A1）. Osteoclast fusion transcripts transmembrane 7 subfamily member 4 （tm7sf4） and nuclear factor of activated T-cell cytoplasmic 1 （nfatcl） where downregulated in response to vitamin D metabolites. Osteoclast number and resorption activity were also increased. Both 25（OH）D3 and 1,25（OH）2D3 reduced osteoclast size and number when co-treated with RANKL and M-CSF. The evidence for VDR expression in resorbing osteoclasts in vivo and low-dose effects of 1,25（OH）2D3 on osteoclasts in vitro may therefore provide insight into the effects of clinical vitamin D treatments, further providing a counterpoint to the high-dose effects reported from in vitro experiments.

Dose-dependent effects of NMDA on retinal and optic nerve morphology in rats

AIM: To investigate dose-dependent effects of N-methylD-aspartate(NMDA) on retinal and optic nerve morphology in rats.METHODS: Sprague Dawley rats, 180-250 g in weight were divided into four groups. Groups 1, 2, 3 and 4 were intravitreally administered with vehicle and NMDA at the doses 80, 160 and 320 nmol respectively. Seven days after injection, rats were euthanized, and their eyes were taken for optic nerve toluidine blue and retinal hematoxylin and eosin stainings. The TUNEL assay was done for detecting apoptotic cells.RESULTS: All groups treated with NMDA showed significantly reduced ganglion cell layer(GCL) thickness within inner retina, as compared to control group. Group NMDA 160 nmol showed a significantly greater GCL thickness than the group NMDA 320 nmol. Administration of NMDA also resulted in a dose-dependent decrease in the number of nuclei both per 100 μm GCL length and per 100 μm2 of GCL. Intravitreal NMDA injection caused dosedependent damage to the optic nerve. The degeneration of nerve fibres with increased clearing of cytoplasm was observed more prominently as the NMDA dose increased. In accordance with the results of retinal morphometry analysis and optic nerve grading, TUNEL staining demonstrated NMDA-induced excitotoxic retinal injury in a dose-dependent manner.CONCLUSION: Our results demonstrate dose-dependent effects of NMDA on retinal and optic nerve morphology in rats that may be attributed to differences in the severity of excitotoxicity and oxidative stress. Our results also suggest that care should be taken while making dose selections experimentally so that the choice might best uphold study objectives.

Gender May Affect the Dose-Dependent Action of Capsaicinoids on Plasma and Hepatic Cholesterol Levels of Rats

Sex differences on the effect of dose-dependent capsaicinoids on lipid metabolism were studied in rats. 24 rats of each sex were administered orally 0 mg/kg, 2.5 mg/kg, 5 mg/kg or 7.5 mg/kg capsaicinoids daily for 28 days. In male rats, body weight gained, and the levels of total lipids, total cholesterol and triglycerides in the liver were significantly decreased as the dose of capsaicinoids increased. On the other hand, plasma total cholesterol (TC), triglycerides (TG), HDL- and LDL-cholesterol concentration and liver weight were not affected by capsaicinoids. While in female rats, plasma TC, TG, HDL-C and LDL-C concentration, liver total lipids, TC and TG concentration were significantly decreased as the dose of capsaicinoids increased. The mRNA level of hepatic TRPV1, ileac ASBT and IBABP were increased as the dose of capsaicinoids increased in all rats groups. The mRNA level of hepatic HMG-CoA reductase, CYP7A1 and FXR were significantly decreased in female rats groups. These results show that the hypocholesterolemic effect of capsaicinoids in dose-dependent manner in rats was mediated by inhibited synthesis of endogenous cholesterol, female rats were more sensitive than male rats on hypolipidemic effect of capsaicinoids.

Pregabalin induced balance disorder,asthenia,edema,and constipation in an elderly adult:A case report

BACKGROUND Pregabalin is widely used to treat neuropathic pain associated with postherpetic neuralgia.To our knowledge,this is the first report on simultaneously occurring dose-related adverse drug reactions(ADRs)of balance disorder,asthenia,peripheral edema,and constipation in an elderly patient after pregabalin.CASE SUMMARY A 76-year-old female with a history of postherpetic neuralgia was prescribed pregabalin(300 mg daily).After taking pregabalin for 7 d,the patient developed balance disorder,weakness,peripheral pitting edema(2+),and constipation.On days 8-14,the pregabalin dose was reduced to 150 mg/d based on creatinine clearance.The patient’s peripheral edema improved significantly with the disappearance of all other adverse symptoms.On day 15,the pregabalin dose was increased to 225 mg/d to relieve pain.Unfortunately,the symptoms mentioned earlier gradually reappeared after 1 wk of pregabalin treatment.However,the complaints were not as severe as when taking 300 mg/d pregabalin.The patient consulted her pharmacist by telephone and was advised to reduce the dose of pregabalin to 150 mg/d and add acetaminophen(0.5 g,q6h)to relieve pain.The patient’s ADRs gradually improved over the following week.CONCLUSION Older patients should be prescribed a lower initial dose of pregabalin.The dose should be titrated to the maximum tolerable dose to avoid dose-limiting ADR.Dose reduction and the addition of acetaminophen may help limit ADR and improve pain control.

A dose-dependent bimodal switch by homologous Aux/IAA transcriptional repressors

Combinatorial interactions between different regulators diversify and enrich the chance of transcriptional regulation in eukaryotic cells.However,a dose-dependent functional switch of homologous transcriptional repressors has rarely been reported.Here,we show that SHY2,an auxin/indole-3-acetic acid(Aux/IAA)repressor,exhibits a dose-dependent bimodal role in auxin-sensitive root-hair growth and gene transcrip-tion in Arabidopsis,whereas other Aux/lAA homologs consistently repress the auxin responses.The co-repressor(TOPLESS[TPL])-binding affinity of a bimodal Aux/IAA was lower than that of a consistently re-pressing Aux/IAA.The switch of a single amino acid residue in the TPL-binding motif between the bimodal form and the consistently repressing form switched their TPL-binding affinity and transcriptional and bio-logical roles in auxin responses.Based on these data,we propose a model whereby competition between homologous repressors with different co-repressor-binding affinities could generate a bimodal output at thetranscriptional anddevelopmental levels.

Assessment of Benchmark Dose in BEAS-2B Cells by Evaluating the Cell Relative Viability with Particulates in Motorcycle Exhaust via the Air-liquid Interface Exposure

Objective This study aimed to use an air-liquid interface(ALI)exposure system to simulate the inhalation exposure of motorcycle exhaust particulates(MEPs)and then investigate the benchmark dose(BMD)of MEPs by evaluating cell relative viability(CRV)in lung epithelial BEAS-2B cells.Methods The MEPs dose was characterized by measuring the number concentration(NC),surface area concentration(SAC),and mass concentration(MC).BEAS-2B cells were exposed to MEPs at different concentrations via ALI and CRV was determined using Cell Counting Kit(CCK-8)assay.BMD software was applied to calculate BMD and the lower limit of benchmark dose(BMDL)according to Akaike Information Coefficient(AIC),with P-value based on Hill,Linear,Polynomial,and Power model.Results Our results reveal that BMD of NC and SAC were estimated by the best-fitting Hill model,while MC was estimated by Polynomial model.The BMDL for CRV following ALI exposure to MEPs were as follows:364.2#/cm^(3)for NC;0.662×10^(7)nm^(2)/cm^(3)for SAC;and 0.278μg/m^(3)for MC.Conclusion These results indicate that MEPs exposure via ALI system induces a dose-dependent decrease of CRV and provides the potential exposure threshold of MEPs in a lung cell model.

Dose-dependent regulation of oligodendrocyte specification by β-catenin signaling

Dear Editor, Although various components of the Wnt/β-catenin pathway have been investigated, there are conflicting reports on the roles of Wnt/β-catenin signaling in oligodendrogenesis and differentiation. For instance, the △Exon3 mutation of β-catenin[14], which stabilizes β-catenin by deletion of the phosphorylation site for the destruction complex, significantly inhibits the differentiation of oligodendrocytes, but knockout of β-catenin also delays it.

Inhibitory effect of Salicornia europaea on the marine alga Skeletonema costatum

Exploiting the negative biochemical interference between plants and algal species has been suggested as a method to control harmful algal blooms. In this work, we investigated the inhibitory effect of the salt marsh halophyte Salicornia europaea against the marine alga Skeletonema costatum. S. europaea suppressed the growth of S. costatum in a nutrient-sufficient co-culture system, indicating that the inhibition of algal growth was because of the phytotoxic effect of S. europaea, rather than nutrient competition. We tested aqueous and organic extracts from S. europaea roots against S. costatum. The organic ex- tracts inhibited growth and affected the cell size and chlorophyll a content of S. costatum in a dose-dependent manner. Among the three tested organic extracts, the methanol extract had the greatest effects on S. costatum, followed by butanol extract, and then the chloroform extract. Two flavonoids, rutin and quercetin-3-13-D-glucoside, were identified in the methanol extract by high performance liquid chromatography. The concentration of rutin was much higher than that of quercetin-3-13-D-glucoside. In an algal bioassay, rutin inhibited the growth of S. costatum and the inhibitory effect increased with increasing rutin concen- tration and with decreasing initial algal density. Therefore, we concluded that S. europaea negatively affects the growth of S. costatum, and that rutin, a metabolite of S. europaea, may play a role in this inhibitory effect.

USE OF CHRONOLITHOTHERAPY FOR BETTER INDIVIDUAL HEALTHCARE AND WELFARE

Man＇s innate clocks functioning allows to understand WHEN and WHY therapies are efficient. Vigil chronotypes determination and respect allows to avoid scholars＇ failure. Performances depend on chronotypes and time changes. Both minimal and maxima/durations of night sleep cycles result from interactions between endogenous and exogenous clocks. Our ecoexotope is structured by solar, lunar and terrestrial rhythms which are synchronisers for endophysiotope clocks. Man night sleep changes depend on lunar cycles entrainment. Sleep analyses point to circa-annual solar rhythms used as controls to evidence circa-monthly lunar ones. To evidence physiological responses individual longitudinal records are used. To evidence lithotherapeutic effects, stimuli responses are tested according to a double-blind placebo-controlled survey. WHAT mineral to chose？, WHY？, HOW to treat？, WHEN？ Compared with controls, jadeite or nephrite enhances night sleep quality with a 15 fold decrease of awakenings and urinations. The highest placebo effect was below 4 fold increase. Depending on minerals and trace elements, properties change. The mineral crystal structure is evidenced to have an action. The contact area with the skin is a limiting factor. Placebo effects are greater during the day phase. Red jasper treatment enhances the number and intensity of diurnal physical working. Minerals act in a dose-dependent manner and in synergy. Hematite sole gives a placebo effect, but increases the effect of serpentinite by a 15 fold value. Within a clocks network, the latency phase of the whole is shorter than the shortest latency phase of each clock, enhancing the system reactivity.

Effects of scandium chloride on osteogenic and adipogenic differentiation of mesenchymal stem cells

Mesenchymal stem cells(MSCs)are multi-potent cells that are able to differentiate and mature into various types of cells under a certain microenvironment for cell therapy and tissue regeneration.Scandium(Sc),an important rare earth element,recently has been intensively investigated in biomedical fields as well as industrial engineering,and chloride channels have been proven to be able to affect osteogenic differentiation.Thus,it is significant to investigate effects of ScCl_(3)on cell activities of MSCs.In this paper,rat bone MSCs(rBMSCs)were co-cultured with various concentrations of ScCl_(3)(1×10^(-8),1×10^(-6),and 1×10^(-4)mol/L)to evaluate their influence on cell proliferation as well as osteogenic and adipogenic differentiation in vitro.The results indicate that ScCl_(3)promotes the proliferation of rBMSCs initially,which is yet reduced upon ion accumulation.We used immunofluorescence staining,quantitative real time polymerase chain reactions,and assays measuring alkaline phosphatase activity,mineralized deposits,and intracytoplasmic lipids to reveal that rBMSCs treated with ScCl_(3)at concentrations of 1×10^(-8)-1×10^(-6)mol/L can enhance levels of osteogenic differentiation in a dosedependent manner and reduce adipogenic differentiation to a certain degree through Wnt/β-catenin signaling pathway.These results indicate that appropriate concentrations of ScCl_(3)can improve osteogenic differentiation in the lineage commitment of rBMSCs,and thus,promote bone remodeling.This study implies that ScCl_(3) possesses great potentials in the treatment of bone diseases and would provide new strategy of designing composites by SiCl3 doping for biomedical applications in the future.

A novel real-time cell electronic analysis technology for the authentication and quality control of natural medicines

The study was designed to explore the potential applications of the real-time cell electronic analysis technology in the quality evaluation of natural medicines. The natural medicinal Flos Carthami was discussed as a methodological example and the specific time/dose-dependent cell response profiles （TCRPs） were produced by the real-time cell electronic analysis technology. The similarity and bioactivity were obtained by analyzing all TCRPs. Meanwhile, an HPLC method according to the Chinese Pharmacopeia （edition 2010） was used to evaluate the quality of Flos Carthami. The correlation was obtained by comparing the results produced by the two different approaches. By analyzing the data, five different samples ofFlos Carthami can produce remarkably similar TCRPs. The quality ofFlos Carthami was evaluated by both the HPLC and the TCRPs analysis-based approaches and similar results were obtained. The results suggest that the same natural medicine from different locations could produce similar TCRPs. By analyzing the TCRPs, the bioactivity and quality evaluation of natural medicines can be obtained. This technology is a physiologically relevant approach for the quality evaluation of natural medicines. The ultimate aim of our study is to establish a new standard for quality evaluation.

Respiratory flora:The potential biomarker of radiation-induced pulmonary injury

Radiation-induced pulmonary injury is a major dose-limiting toxicity that occurs due to thoracic radiotherapy.And the most widely used high-throughput technology,16S ribosomal RNA sequencing,is adopted for bacterial classification and identification of airway microbiome analysis.In this study,we provide novel insights into the composition pattern and predicted function of the lung microbiome in RIPI rats.Certain genus and species change in a dose-dependent manner,which might be capable of serving as novel bacterial biomarkers,as well as the potential targets for the future diagnosis or treatment of RIPI.In summary,our findings provide a vital reference for RIPI study,and will contribute to investigate the novel therapeutic or preventive management for RIPI.