Associations of Dietary Anthocyanidins Intake with Bone Health in Children: A Cross-Sectional Study.

PURPOSE: Bone health and body composition share several common mechanisms like oxidative stress and inflammation. Anthocyanins have antioxidant and anti-inflammatory properties. We have reported that anthocyanins are associated with better body composition in children, but the associations with bone health have not been elucidated. We aimed to explore the association of anthocyanins with bone mineral content (BMC) and bone mineral density (BMD) at multiple sites in children. METHODS: In this cross-sectional study, 452 Chinese children aged 6-9 years were recruited. A validated 79-item food frequency questionnaire was used to collect dietary information. BMC and BMD at multiple sites (whole body; whole body excluding head, WBEH; limbs; arms; legs) were measured by dual-energy X-ray. RESULTS: Higher dietary intake of total anthocyanidins (per one standard deviation increase) was associated with a 1.28-13.6 g (1.31-1.60%, compared to median) higher BMC at all sites and a 3.61-6.96 mg (0.65-0.90%) higher BMD at the whole body, WBEH, and arm sites after controlling for a number of possible covariates. The results were similar and more pronounced for cyanidin, but not for delphinidin and peonidin. Higher dietary intake of cyanidin (per one standard deviation increase) was associated with a 1.33-15.4 g (1.48-1.68%) higher BMC at all sites and a 4.15-7.77 mg (0.66-1.00%) higher BMD at all sites except the legs. No statistically significant associations with BMC or BMD were found for dietary intake of delphinidin and peonidin. CONCLUSIONS: Higher dietary intake of total anthocyanidins and cyanidins were associated with higher BMC and BMD in Chinese children.

Bone morphogenetic protein 4 is involved in cadmium-associated bone damage.

Cadmium (Cd) is a well-characterized bone toxic agent and can induce bone damage via inhibiting osteogenic differentiation. Bone morphogenetic protein (BMP)/SMAD signaling pathway can mediate osteogenic differentiation, but the association between Cd and BMP/SMAD signaling pathway is yet to be illuminated. To understand what elements of BMPs and SMADs are affected by Cd to influence osteogenic differentiation and if BMPs can be the biomarkers of which Cd-induced osteoporosis, human bone marrow mesenchymal stem cells (hBMSCs) were treated with cadmium chloride (CdCl2) in vitro to detect the expression of BMPs and SMADs, and 134 subjects were enrolled to explore if the BMPs can be potential biomarkers of Cd-associated bone damage. Our results showed that Cd exposure significantly promoted the adipogenic differentiation of hBMSCs and inhibited its osteogenic differentiation by inhibiting the expression of BMP-2/4, SMAD4, and p-SMAD1/5/9 complex. And mediation analyses yielded that BMP-4 mediated 39.32% (95% confidence interval 7.47, 85.00) of the total association between the Cd and the risk of Cd-associated bone damage. Moreover, during differentiation, BMP-4 had the potential to enhance mineralization compared with CdCl2 only group. These results reveal that BMP-4 can be a diagnostic biomarker and therapeutic target for Cd-associated bone damage.

Associations of the Gut Microbiota Composition and Fecal Short-Chain Fatty Acids with Leukocyte Telomere Length in Children Aged 6 to 9 Years in Guangzhou, China: A Cross-sectional Study.

BACKGROUND: Telomere length (TL) serves as a marker of cellular senescence and appears to plateau between the age of 4 y and young adulthood, after which the gut microbiota are supposed to be established. However, scarce data are available regarding the correlation between gut microbiota composition and TL in the pediatric population. OBJECTIVES: We aimed to investigate whether the gut microbiota and the concentrations of SCFAs in feces are associated with leukocyte TL in children. METHODS: In total, 401 children aged 6-9 y from Guangzhou were enrolled in this cross-sectional study. qPCR was used to determine relative TL in peripheral blood leukocytes. The gut microbiota was characterized by 16S ribosomal RNA amplicon sequencing and the fecal concentrations of total SCFAs and SCFA subtypes were determined using HPLC. The multivariate methods with an unbiased variable selection (MUVR) algorithm and partial least square models were used to select predictable operational taxonomic units (OTUs). Further correlation analyses were performed based on multiple linear regression models with adjustment for covariates and false discovery rate. RESULTS: With the use of MUVR, 35 relevant and minimal optimal OTUs were finally selected. Multiple linear regression analysis showed that the abundance of several OTUs, including OTU334 (belonging to the genus Family XIII AD3011 group), OTU726 (belonging to the species Lachnoclostridium phocaeense), OTU1441 (belonging to the genus Ruminococcus torques group), OTU2553 (belonging to the genus Lachnospiraceae UCG-010), and OTU3375 (belonging to the family Lachnospiraceae), was negatively associated with leukocyte TL (ß: -0.187 to -0.142; false discovery rate (FDR)-corrected P value (PFDR) = 0.009-0.035]. However, neither SCFA subtype nor total SCFA content in feces exhibited significant associations with TL (ß: -0.032 to 0.048; PFDR = 0.915-0.969). CONCLUSIONS: The gut microbiota, but not fecal SCFA concentration, was significantly associated with TL in this pediatric population.

Association of environmental cadmium exposure and bone remodeling in women over 50 years of age.

Chronic cadmium (Cd) toxicity is a significant health concern, and the mechanism of long-term low-dose Cd exposure on bone has not been fully elucidated yet. This study aimed to assess the association between long-term environmental Cd exposure and bone remodeling in women who aged over 50. A total of 278 non-smoking subjects from Cd-polluted group (n = 191) and non-Cd polluted group (n = 87) were investigated. Bone mineral density (BMD), the levels of three bone turnover markers (BTMs), including total procollagen type 1 amino-terminal propeptide (P1NP), collagen type 1 cross-linked C-telopeptide (ß-CTX), bone-specific alkaline phosphatase (BALP), together with serum soluble receptor activator of nuclear factor-κB ligand (sRANKL) and osteoprotegerin (OPG) were determined. Early markers of renal dysfunction were measured as well. Urinary Cd concentrations ranged from 0.41 to 87.31 µg/g creatinine, with a median of 4.91 µg/g creatinine. Age, BMD, T-score, and prevalence of osteoporosis showed no statistical differences among the quartiles of urinary Cd concentrations, while serum levels of P1NP, ß-CTX, and OPG were higher in the upper quartiles. Multivariate linear regression models indicated significantly positive associations of urinary Cd concentration with serum levels of P1NP, ß-CTX, BALP, sRANKL, and OPG. A ridge regression analysis with T-score and the three BTMs, sRANKL, and OPG, adjusted for age and body mass index (BMI), indicated that except for age and Cd exposure, ß-CTX was a predictor of T-score. These findings demonstrated that Cd may directly accelerate bone remodeling. Serum ß-CTX might be an appropriate biochemical marker for evaluating and monitoring Cd-related bone loss. Capsule: Cadmium (Cd) may directly accelerate bone remodeling and serum ß-CTX is a valuable biochemical marker for evaluating Cd-related bone loss.

Low-dose cadmium exposure acts on rat mesenchymal stem cells via RANKL/OPG and downregulate osteogenic differentiation genes.

Chronic cadmium (Cd) toxicity is a significant health concern, and the mechanism of long-term low-dose Cd exposure on bone has not been fully elucidated till date. This study aimed to assess the association between rat mesenchymal stem cells (MSCs) and long-term Cd exposure through 38-week intake of CdCl2 at 1 and 2 mg/kg body weight (bw). Increased gene expression of receptor activator of NF-κB ligand (RANKL) and decreased gene expression of osteoprotegerin (OPG) were observed. Fold change of RANKL gene expression (fold change = 1.97) and OPG gene expression (fold change = 1.72) showed statistically significant differences at dose 2 mg/kg bw. Decreased expression of key genes was observed during the early osteogenic differentiation of MSCs. The gene expression of Osterix in 1 mg/kg bw group was decreased by 3.70-fold, and the gene expressions of Osterix, Osteopontin, collagen type I alpha 2 chain (COL1a2) and runt-related transcription factor 2 (RUNX2) in 2 mg/kg bw group were decreased by 1.79, 1.67, 1.45 and 1.35-folds, respectively. Exposure to CdCl2 induced an increase in the renal Cd load, but only an adaptive response was observed, including increased expression of autophagy-related proteins LC3B and Beclin-1, autophagy receptor p62, and heme oxygenase 1 (HO-1), which is an inducible isoform that releases in response to stress. There were no significant changes in the urinary low molecular weight proteins including N-acetyl-b-D-glucosaminidase (NAG), ß2-microglobulin and albumin (U-Alb). Urinary calcium (Ca) excretion showed no increase, and no obvious renal histological changes. Taken together, these results indicated that the chronic CdCl2 exposure directly act on MSCs through RANKL/OPG pathway and downregulate the key genes involved in osteogenic differentiation of MSCs. The toxic effect of Cd on bone may occur in parallel to nephrotoxicity.

[Differential gene expressions in cells with low-dose hydrogen peroxide-induced adaptive response: a study with FDDRT-PCR].

OBJECTIVE: To identify differentially expressed genes in human embryo lung fibroblasts MRC-5 with adaptive response induced by low concentration of hydrogen peroxide (H(2)O(2)) using fluorescent differential display-RT-PCR (FDDRT-PCR). METHODS: The dose-effect pattern of H2O2 toxicity was determined using MTT assay, and the dose of 0.088, 0.88, 8.8, 88 micro;mol/L was defined as the low concentration, and 1100 micromol/L as the high concentration. Adaptive response model was established in MRC-5 cells verified using LDH release and cell apoptosis analyses. Differentially expressed genes in the cells with exposure to different doses of H(2)O(2) were detected by FDDRT-PCR, and some of the differentially displayed genes were determined using real-time quantitative PCR. RESULTS: Cells challenged with high-concentration H(2)O(2) for 1 h after H(2)O(2) pretreatment at low concentrations for 24 h resulted in lessened toxic effect in comparison with direct high-concentration H(2)O(2) exposure. The adaptive response of the cells was most obvious with H(2)O(2) pretreatment at 0.88 micromol/L. Altogether 60 differentially expressed genes were detected with FDDRT-PCR in different treatment groups, and 5 of them were identified and verified, including 1 unknown gene and 4 known genes (bcl-2, EIF3S5, NDUFS4 and RPS10). CONCLUSION: According to the results of FDDRT-PCR, the genes bcl-2, EIF3S5, NDUFS4 and RPS10 can be involved in H(2)O(2)-induced adaptive response of the MRC-5 cells.

[Differentially express genes in human embryonic lung fibroblasts with damage tolerance induced by low-dose hydroquinone].

OBJECTIVE: To observe the differentially expressed genes in human embryonic lung fibroblasts (HELF) induced by small-dose hydroquinone (HQ) using fluorescence differential display-PCR (DD-PCR). METHODS: According to the dose-effect relation of HQ toxicity we established previously, HQ dose that did not induce observed cell damage or proliferation arrest was defined as low dose (100 pmol/L), and that causing obvious cell damage as the high dose (100 micrommol/L). The cells were then treated with low or high dose of HQ, or exposed to high-dose HQ following pretreatment with low-dose HQ for some time, respectively. Fluorescence DD-PCR was performed and 33 differentially expressed genes were identified in the cells with different treatments, and 8 of the identified genes were amplified, cloned, sequenced and blasted. RESULTS: Seven of the 8 amplified genes were unknown genes, and the left one was identified as a known gene highly homologous to that encoding Homo sapiens Rap1 interacting factor 1 (RIF1). CONCLUSION: Low-dose HQ can induce damage tolerance in HELF, and identification of the differentially expressed genes may provide valuable sight into the mechanism of HQ-induced damage tolerance.

[Research on differential display genes of tolerant-damage induced by trichloroethylene].

OBJECTIVE: To observe the differentially expressed genes of the human normal liver cell (L-02) induced by low concentration of trichloroethylene (TCE). METHODS: The dose-effect relation of TCE toxicity was analyzed by means of MTT. 5 micromol/L was chosen as low concentration while 40 micromol/L as high concentration. Then L-02 were treated with low concentration, high concentration, pretreated with low concentration then attacked with high concentration of TCE respectively. Fluorescence differential display polymerase chain reaction (Fluoro DD-PCR) was used to search differentially expressed genes of the different treatment groups of TCE. Results 51 differential expressed strap were found, 11 differential straps have been cloned and sequenced. 9 of them were known gene, while 2 of them were new genes. CONCLUSION: The differential straps would be identified to provide scientific base for research deeply the mechanism of low concentration TCE inducing adaptive response of L-02.

[Study on differential display genes of tolerant-damage of MRC-5 induced by formaldehyde of low dose].

OBJECTIVE: To observe the differentially expressed genes of the human embryo lung fibroblast (MRC-5) induced by formaldehyde (FA) of low dose using fluoro DD-PCR. METHODS: The dose-effect relation of FA toxicity to MRC-5 was acquired, No observed damage effect or proliferation concentration was used as low dose, and obvious damage concentration was used as high dose. MRC-5 was treated with low and high dose, and treated with high dose after pretreated with low dose for some time. Then Fluoro differential display polymerase chain reaction (Fluoro DD-PCR) was used to search differentially expressed genes of the differently treated groups of FA. 61 differential display straps were acquired and 11 of them were reamplified, cloned, sequenced and blasted. RESULTS: According to the dose-effect relation of FA toxicity to MRC-5, 100 micromol/L was choosed as low dose and 10 mmol/L was choosed as high dose. Samples of differently treated groups were amplified by means of fluro-DD-PCR, 61 differentially expressed straps were acquired. 11 differential display straps have been cloned, sequenced and blasted. Two of them were known genes: one was highly homologous to nuclear factor of activated T-cells 5 (NFAT5) and the other was highly homologous to tetratricopeptide repeat domain 3(TPRD-3). Nine of them were new genes. CONCLUSION: It seemed that FA of low dose could promote MRC-5 proliferation and find 61 differentially expressed genes of differently treated groups, and the result of clone could provide scientific base for mechanism of FA toxicity research.

[Two-dimensional electrophoresis and mass spectrometry analysis on effects of trichloroethylene on protein of L-02 liver cells].

OBJECTIVE: To study the effects of trichloroethylene (TCE) on the protein in L-02 cells in vitro. METHODS: Thiazolyl blue and Trypan blue tests were used to investigate the cytotoxicity of TCE to L-02 liver cell. The 2-D electrophoresis was used to analyse the expression of proteins in L-02 liver cells. The differentially expressed protein spots were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-TOF-MS). RESULTS: When the concentration of TCE exceeded 30 micromol/L, there was distinct cytotoxicity to L-02 cell (P < 0.05). Selected 40 micromol/L to treat L-02 liver cells and analyze the differential proteome expression, the results showed that the expression level of 37 protein spots was up-regulated and 15 protein spots was down-regulated. And 15 proteins were identified by MALDI-TOF-TOF-MS. CONCLUSION: TCE can change the proteome expression of L-02 liver cell. It should provide the fundamental information to identify proteins related to TCE in further study.

[Study on differential proteomic expression in human liver cells stimulated by trichloroethylene with proteomics].

OBJECTIVE: To explore the differential proteomic expression in human liver cells L-02 induced by different dosages of trichloroethylene (TCE). METHODS: Human liver cells L-02 were treated with different concentrations of TCE and the solvent control (dimethylsulfoxide). The total cellular proteins were separated using 2DE and visualized with silver staining after TCE treatment. The images were analyzed with Image Master 2D Platinum 5.0 analysis software. The differentially expressed protein spots were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-TOF-MS). RESULTS: Fifteen protein spots with significant difference were found, and went upward or downward or disappeared after the stimulation of TCE with different dosages, which indicated that TCE induced the change of the proteomic expression in the liver cells. The mass spectrum identification and the IPI human database retrieval were used for identifying 9 proteins related to the L-02 Liver cells induced by TCE. CONCLUSION: The result provides an insight to TCE-related molecular mechanism and which might be useful for further study of the TCE-associated proteins and molecular markers.