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Brama M, Politi L, Santini P, Migliaccio S, Scandurra R. Cadmium-induced apoptosis and necrosis in human osteoblasts: role of caspases and mitogen-activated protein kinases pathways. J Endocrinol Invest 2012; 35:198-208. [PMID: 21697648 DOI: 10.3275/7801] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cadmium is a widespread environmental pollutant which induces severe toxic alterations, including osteomalacia and osteoporosis, likely by estrogen receptor-dependent mechanisms. Indeed, cadmium has been described to act as an endocrine disruptor and its toxicity is exerted both in vivo and in vitro through induction of apoptosis and/or necrosis by not fully clarified intracellular mechanism(s) of action. Aim of the present study was to further investigate the molecular mechanism by which cadmium might alter homeostasis of estrogen target cells, such as osteoblast homeostasis, inducing cell apoptosis and/or necrosis. Human osteoblastic cells (hFOB 1.19) in culture were used as an in vitro model to characterize the intracellular mechanisms induced by this heavy metal. Cells were incubated in the presence/ absence of 10-50 μM cadmium chloride at different times and DNA fragmentation and activation of procaspases- 8 and -3 were induced upon CdCl(2) treatment triggering apoptotic and necrotic pathways. Addition of caspase-8 and -3 inhibitors (Z-IETD-FMK and Z-DQMD-FMK) partially blocked these effects. No activation of procaspase-9 was observed. To determine the role of mitogen-activated protein kinases (MAPK) in these events, we investigated c-jun N-terminal kinase (JNK), p38 and extracellular signal-regulated protein kinase (ERK1/2) phosphorylation which were activated by 10 μM CdCl(2). Chemical inhibitors of JNK, p38, and ERK1/2, SP600125, SB202190, and PD98059, significantly reduced the phosphorylation of the kinases and blunted apoptosis. In contrast, caspase inhibitors did not reduce the cadmium-induced MAPK phosphorylation, suggesting an independent activation of these pathways. In conclusion, at least 2 pathways appear activated by cadmium in osteoblasts: a direct induction of caspase-8 followed by activation of caspase-3 and an indirect induction by phosphorylation of ERK1/2, p38, and JNK MAPK triggering activation of caspase-8 and -3.
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Affiliation(s)
- M Brama
- Department of Biochemical Sciences, Sapienza University, Rome, Italy
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Lukacinova A, Benacka R, Sedlakova E, Lovasova E, Nistiar F. Multigenerational lifetime low-dose exposure to heavy metals on selected reproductive parameters in rats. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2012; 47:1280-1287. [PMID: 22540652 DOI: 10.1080/10934529.2012.672132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The aim of the present investigation was to evaluate the effects of multigenerational (P, F1 and F2) exposure to low doses of lead, mercury and cadmium dissolved in tap water on the reproductive potency of Wistar rats and the physical health of their progeny. The animals were divided into 4 groups - control (C) and 3 groups intoxicated by metals (Pb, 100 μM; Hg, 1 μM; Cd, 20 μM, respectively). Females gave births from the 13th to the 78th week of experiment. Parameters of reprotoxicity such as number of litters, total number of neonates (assigned in the birth day), and number of weanlings (28th day after birth) were measured in 13-week intervals. Our data show an increase of most reproductive parameters in parental generation of rats exposed to lead and mercury and a decrease of reproductive parameters of exposed animals in subsequent F1 and F2 generations. Exposure to cadmium had no significant effect on the reproductive parameters in comparison with the control group.
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Affiliation(s)
- Agnesa Lukacinova
- Department of Physiology, Faculty of Medicine, Safarik University, Kosice, Slovak Republic
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Chen X, Zhu G, Jin T, Shao C, Gu S, Tan M, Zhang Y, Xiao H, Hu H, Yu Y. Bone-prognostic status after cessation of cadmium exposure for one month in male rats. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2012; 62:165-175. [PMID: 21630100 DOI: 10.1007/s00244-011-9685-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 05/16/2011] [Indexed: 05/30/2023]
Abstract
This study investigated bone status after decreased cadmium (Cd) exposure in male rats. Sprague-Dawley male rats were randomly divided into three groups. One group was injected subcutaneously with sodium chloride as control. The others were given CdCl2 by subcutaneous injection at doses of 0.5 mg Cd/kg body weight (bw) for 2 months (Cd+2m) and for 3 months (Cd+3m). For the Cd+2m group, the rats were shifted to cessation of Cd injection for 1 month after 2 months' exposure. At month 3, micro-computed tomography (micro-CT) analyses were performed on the proximal tibia and lumbar spine, and urine was collected from all rats. Rats were then killed and blood collected for metabolic-marker measurement and Cd assay. Bone tissues were also collected for bone-mass assay, biomechanical test, and bone-histology analysis. Cd burdens of rats in the Cd+2m and Cd+3m groups were both significantly greater than those in the control group. Cd burdens of rats were lower in the Cd+2m group compared with the Cd+3m group. Bone damage occurred in the Cd+2m and Cd+3m groups compared with the control group (p<0.05), but no significant improvement was found in the Cd+2m group compared with the Cd+3m group. Cd damage to bone could not be reversed over the short term. More attention should be paid to Cd's toxic effects on bone after decreased exposure.
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Affiliation(s)
- Xiao Chen
- Institute of Radiation Medicine, Fudan University, Xietu Road, Shanghai, 200032, China
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Chen X, Zhu G, Jin T, Qin B, Zhou W, Gu S. Cadmium is more toxic on volume bone mineral density than tissue bone mineral density. Biol Trace Elem Res 2011; 144:380-7. [PMID: 21656269 DOI: 10.1007/s12011-011-9106-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 05/30/2011] [Indexed: 10/18/2022]
Abstract
It has been showed that Cd induces low areal bone mineral density, but we do not know the effect of Cd on cubic bone density. This study was aimed to investigate the effects of Cd on volumetric bone mineral density (VBMD) and tissue bone mineral density (TBMD) in male rats. Twenty-four Sprague-Dawley male rats were randomly divided into four groups that were given cadmium chloride by subcutaneous injection at doses of 0, 0.1, 0.5, and 1.5 mg/kg body weight for 8 weeks, respectively. Then, microcomputed tomography scanning was performed on the proximal tibia, and region of interest was reconstructed using microview software. The VBMD, bone volume fraction of rats treated with 1.5 mg Cd/kg, were significantly decreased compared to control (p < 0.01). The trabecular numbers of rats exposed to Cd were all significantly decreased relative to control (p < 0.05). The trabecular separation of rats treated with 1.5 mg Cd/kg was obviously increased compared to control (p < 0.01). However, Cd had no obvious influence on TBMD. Cd induced low VBMD but not TBMD; Cd effect on bone may be related with trabecular bone loss but not with trabecular bone demineralization.
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Affiliation(s)
- Xiao Chen
- Institute of Radiation Medicine, Fudan University, 200032, Shanghai, China
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Arbon KS, Christensen CM, Harvey WA, Heggland SJ. Cadmium exposure activates the ERK signaling pathway leading to altered osteoblast gene expression and apoptotic death in Saos-2 cells. Food Chem Toxicol 2011; 50:198-205. [PMID: 22019892 DOI: 10.1016/j.fct.2011.10.031] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 10/05/2011] [Accepted: 10/07/2011] [Indexed: 11/19/2022]
Abstract
Recent reports of cadmium in electronic waste and jewelry have increased public awareness regarding this toxic metal. Human exposure to cadmium is associated with the development of osteoporosis. We previously reported cadmium induces apoptosis in human tumor-derived Saos-2 osteoblasts. In this study, we examine the extracellular signal-regulated protein kinase (ERK) and protein kinase C (PKC) pathways in cadmium-induced apoptosis and altered osteoblast gene expression. Saos-2 osteoblasts were cultured in the presence or absence of 10μM CdCl(2) for 2-72h. We detected significant ERK activation in response to CdCl(2) and pretreatment with the ERK inhibitor PD98059 attenuated cadmium-induced apoptosis. However, PKCα activation was not observed after exposure to CdCl(2) and pretreatment with the PKC inhibitor, Calphostin C, was unable to rescue cells from cadmium-induced apoptosis. Gene expression studies were conducted using qPCR. Cells exposed to CdCl(2) exhibited a significant decrease in the bone-forming genes osteopontin (OPN) and alkaline phosphatase (ALP) mRNA. In contrast, SOST, whose protein product inhibits bone formation, significantly increased in response to CdCl(2). Pretreatment with PD98059 had a recovery effect on cadmium-induced changes in gene expression. This research demonstrates cadmium can directly inhibit osteoblasts via ERK signaling pathway and identifies SOST as a target for cadmium-induced osteotoxicity.
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Affiliation(s)
- Kate S Arbon
- Department of Biology, The College of Idaho, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
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Lukačínová A, Rácz O, Lovásová E, Ništiar F. Effect of lifetime low dose exposure to heavy metals on selected serum proteins of Wistar rats during three subsequent generations. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2011; 74:1747-1755. [PMID: 21549428 DOI: 10.1016/j.ecoenv.2011.04.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 04/05/2011] [Accepted: 04/15/2011] [Indexed: 05/30/2023]
Abstract
The aim of the study was to assess the effects of exposure to low doses of lead, cadmium and mercury dissolved in drinking water (at a concentration 200-fold of maximum allowable concentration) on selected serum proteins of 120 Wistar rats during three subsequent generations. Animals were divided into four groups in all observed generation-control (C) and three experimental groups exposed to low doses of heavy metals (lead acetate in concentration 100 μM; mercuric chloride in 1 μM; cadmium chloride in 20 μM of drinking water). We studied the biochemical parameters as well as total protein, albumin, transferrin and ferritin in the serum. Exposure to lead and mercury shortened life span, decreased body weight of the animals in each generation whereas cadmium had no such effect. Total protein increased after exposure to lead and mercury (P<0.001), albumin increased after exposure to lead and mercury in 1st filial and 2nd filial generation (P<0.05) and insignificantly decreased after exposure to cadmium in parental and 1st filial generation. Transferrin and ferritin increased in all exposed groups and generations (P<0.05). Transferrin and ferritin are good markers for intoxication of rats with heavy metals. For the results evaluation, not only data at the end of experiment should be taken into account, but entire duration of trials (i.e., more time steps), which makes results more objective.
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Affiliation(s)
- Agnesa Lukačínová
- Department of Physiology, Faculty of Medicine, Šafárik University, Trieda SNP 1, 040 66 Košice, Slovak Republic.
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Engström A, Michaëlsson K, Suwazono Y, Wolk A, Vahter M, Akesson A. Long-term cadmium exposure and the association with bone mineral density and fractures in a population-based study among women. J Bone Miner Res 2011; 26:486-95. [PMID: 20734452 DOI: 10.1002/jbmr.224] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
All people are exposed to cadmium (Cd) via food; smokers are additionally exposed. High Cd exposure is associated with severe bone damage, but the public health impact in relation to osteoporosis and fractures at low environmental exposure remains to be clarified. Within the population-based Swedish Mammography Cohort, we assessed urinary Cd [U-Cd, µg/g of creatinine (cr)] as a marker of lifetime exposure and bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) among 2688 women. Register-based information on fractures was retrieved from 1997 to 2009. Associations were evaluated by multivariable regression analyses. In linear regression, U-Cd was inversely associated with BMD at the total body (p < .001), femoral neck (p = .025), total hip (p = .004), lumbar spine (p = .088), and volumetric femoral neck (p = .013). In comparison with women with U-Cd < 0.50 µg/g of cr, those with U-Cd ≥ 0.75 µg/g of cr had odds ratios (ORs) of 2.45 [95% confidence interval (CI) 1.51-3.97] and 1.97 (95% CI 1.24-3.14) for osteoporosis at the femoral neck and lumbar spine, respectively. Among never-smokers, the corresponding ORs were 3.47 (95% CI 1.46-8.23) and 3.26 (95% CI 1.44-7.38). For any first fracture (n = 395), the OR was 1.16 (95% CI 0.89-1.50) comparing U-Cd ≥ 0.50 µg/g of cr with lower levels. Among never-smokers, the ORs (95% CIs) were 2.03 (1.33-3.09) for any first fracture, 2.06 (1.28-3.32) for first osteoporotic fracture, 2.18 (1.20-3.94) for first distal forearm fracture, and 1.89 (1.25-2.85) for multiple incident fractures. U-Cd at low environmental exposure from food in a general population of women showed modest but significant association with both BMD and fractures, especially in never-smokers, indicating a larger concern than previously known.
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Affiliation(s)
- Annette Engström
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
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Brzóska MM. Low-level chronic exposure to cadmium enhances the risk of long bone fractures: a study on a female rat model of human lifetime exposure. J Appl Toxicol 2011; 32:34-44. [DOI: 10.1002/jat.1632] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 10/27/2010] [Accepted: 10/27/2010] [Indexed: 02/02/2023]
Affiliation(s)
- Malgorzata M. Brzóska
- Department of Toxicology; Medical University of Bialystok; Adama Mickiewicza 2C; 15-222; Bialystok; Poland
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Shin M, Paek D, Yoon C. The relationship between the bone mineral density and urinary cadmium concentration of residents in an industrial complex. ENVIRONMENTAL RESEARCH 2011; 111:101-109. [PMID: 21167481 DOI: 10.1016/j.envres.2010.11.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2010] [Revised: 11/16/2010] [Accepted: 11/24/2010] [Indexed: 05/30/2023]
Abstract
BACKGROUND An association between cadmium exposure and bone mineral density (BMD) has been demonstrated in elderly women, but has not been well studied in youths and men. Some studies report either no or a weak association between cadmium exposure and bone damage. OBJECTIVES This study was designed to investigate the relationship between the urinary cadmium (U-Cd) levels and BMD of females and males of all ages. METHODS A total of 804 residents near an industrial complex were surveyed in 2007. U-Cd and BMD on the heel (non-dominant calcaneus) were analyzed with AAS-GTA and Dual-Energy X-ray absorptiometry, respectively. Demographic characteristics were collected by structured questionnaires. Osteoporosis and osteopenia were defined by BMD cut-off values and T-scores set by the WHO; T score>-1, normal; -2.5<T score <-1, osteopenia; and T score <-2.5, osteoporosis. Logistic and multiple linear regressions were applied to estimate the association between U-Cd levels and BMD. RESULTS The U-Cd levels in females (0.64 μg/g creatinine) were higher than those in males (0.48 μg/g creatinine) (p<0.001). With the logistic regression model, osteopenia was associated with high U-Cd levels (≥ 1.0 μg/g creatinine) in females (OR=2.92; 95% CI, 1.51-5.64) and in males (OR=3.37; 95% CI, 1.09-10.38). With the multiple linear regression model, the BMD of the adult group was negatively associated with U-Cd (<0.05), gender (female, p<0.001) and age (p<0.001). The BMD of participants who were ≤ 19 years of age was negatively associated with gender (female, p<0.01), whereas it was positively associated with age and BMI (p<0.001). BMD was not associated with exercise, smoking habits, alcohol consumption, job or parental education. CONCLUSION Results suggested that U-Cd might be associated with osteopenia as well as osteoporosis in both male and female adults. Age and female gender were negatively associated with BMD in the adult group, whereas age was positively associated with BMD in the youth group. Cadmium exposure may be a potential risk factor for lower-BMD and osteopenia symptoms as well as for osteoporosis symptoms.
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Affiliation(s)
- Minah Shin
- Institute of Health and Environment, Department of Environmental Health, School of Public Health, Seoul National University, Gwanak-599, Gwanak-gu, Seoul 151-742, Republic of Korea
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Brzóska MM, Rogalska J, Kupraszewicz E. The involvement of oxidative stress in the mechanisms of damaging cadmium action in bone tissue: a study in a rat model of moderate and relatively high human exposure. Toxicol Appl Pharmacol 2010; 250:327-35. [PMID: 21129391 DOI: 10.1016/j.taap.2010.11.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 11/10/2010] [Accepted: 11/22/2010] [Indexed: 10/18/2022]
Abstract
It was investigated whether cadmium (Cd) may induce oxidative stress in the bone tissue in vivo and in this way contribute to skeleton damage. Total antioxidative status (TAS), antioxidative enzymes (glutathione peroxidase, superoxide dismutase, catalase), total oxidative status (TOS), hydrogen peroxide (H(2)O(2)), lipid peroxides (LPO), total thiol groups (TSH) and protein carbonyl groups (PC) as well as Cd in the bone tissue at the distal femoral epiphysis and femoral diaphysis of the male rats that received drinking water containing 0, 5, or 50mg Cd/l for 6 months were measured. Cd, depending on the level of exposure and bone location, decreased the bone antioxidative capacity and enhanced its oxidative status resulting in oxidative stress and oxidative protein and/or lipid modification. The treatment with 5 and 50mg Cd/l decreased TAS and activities of antioxidative enzymes as well as increased TOS and concentrations of H(2)O(2) and PC at the distal femur. Moreover, at the higher exposure, the concentration of LPO increased and that of TSH decreased. The Cd-induced changes in the oxidative/antioxidative balance of the femoral diaphysis, abundant in cortical bone, were less advanced than at the distal femur, where trabecular bone predominates. The results provide evidence that, even moderate, exposure to Cd induces oxidative stress and oxidative modifications in the bone tissue. Numerous correlations noted between the indices of oxidative/antioxidative bone status, and Cd accumulation in the bone tissue as well as indices of bone turnover and bone mineral status, recently reported by us (Toxicology 2007, 237, 89-103) in these rats, allow for the hypothesis that oxidative stress is involved in the mechanisms of damaging Cd action in the skeleton. The paper is the first report from an in vivo study indicating that Cd may affect bone tissue through disorders in its oxidative/antioxidative balance resulting in oxidative stress.
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Affiliation(s)
- Malgorzata M Brzóska
- Department of Toxicology, Medical University of Bialystok, Adama Mickiewicza 2C, 15-222 Bialystok, Poland.
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Bodo M, Balloni S, Lumare E, Bacci M, Calvitti M, Dell’Omo M, Murgia N, Marinucci L. Effects of sub-toxic Cadmium concentrations on bone gene expression program: Results of an in vitro study. Toxicol In Vitro 2010; 24:1670-80. [DOI: 10.1016/j.tiv.2010.05.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Revised: 05/24/2010] [Accepted: 05/31/2010] [Indexed: 10/19/2022]
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Brzóska MM, Majewska K, Kupraszewicz E. Effects of low, moderate and relatively high chronic exposure to cadmium on long bones susceptibility to fractures in male rats. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2010; 29:235-245. [PMID: 21787608 DOI: 10.1016/j.etap.2010.01.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 01/20/2010] [Accepted: 01/25/2010] [Indexed: 05/31/2023]
Abstract
The study investigated the risk of the femur and tibia fractures on a male rat model of low, moderate and relatively high human exposure to cadmium (1, 5 and 50mg Cd/l in drinking water for 12 months). Bone mineral density (BMD) and biomechanical properties at the proximal and distal femur, and femoral and tibial diaphysis as well as the bone content of mineral and organic components, were evaluated. The exposure to 1mg Cd/l caused only very subtle changes in biomechanical properties at the femoral neck and distal femur. In the rats treated with 5mg Cd/l, a decrease in the distal femur BMD (by 5.5%) and enhanced vulnerability to fracture at the femoral neck, distal femur, and tibia diaphysis were observed. At the highest Cd treatment, the BMD decreased (by 6.5-11%) and the biomechanical properties weakened at all regions of the femur and tibia. Moreover, a decrease in the femur and tibia content of mineral components (by 11.5% and 10%, respectively) and the tibia content of organic components (by 7%) was noted. The results seem to indicate that low chronic exposure to Cd can have no influence on the bone resistance to fracture, whereas moderate (and particularly relatively high) exposure seriously increases the risk of fracture of long bones in males. The observations, together with our findings on an analogous female rat model, provide evidence that males are less vulnerable to Cd-induced demineralization and weakening of biomechanical properties of the femur and tibia than females.
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Affiliation(s)
- Malgorzata M Brzóska
- Department of Toxicology, Medical University of Bialystok, Adama Mickiewicza 2C Street, 15-222 Bialystok, Poland
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Bhattacharyya MH. Cadmium osteotoxicity in experimental animals: mechanisms and relationship to human exposures. Toxicol Appl Pharmacol 2009; 238:258-65. [PMID: 19463839 DOI: 10.1016/j.taap.2009.05.015] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Revised: 05/06/2009] [Accepted: 05/10/2009] [Indexed: 10/20/2022]
Abstract
Extensive epidemiological studies have recently demonstrated increased cadmium exposure correlating significantly with decreased bone mineral density and increased fracture incidence in humans at lower exposure levels than ever before evaluated. Studies in experimental animals have addressed whether very low concentrations of dietary cadmium can negatively impact the skeleton. This overview evaluates results in experimental animals regarding mechanisms of action on bone and the application of these results to humans. Results demonstrate that long-term dietary exposures in rats, at levels corresponding to environmental exposures in humans, result in increased skeletal fragility and decreased mineral density. Cadmium-induced demineralization begins soon after exposure, within 24 h of an oral dose to mice. In bone culture systems, cadmium at low concentrations acts directly on bone cells to cause both decreases in bone formation and increases in bone resorption, independent of its effects on kidney, intestine, or circulating hormone concentrations. Results from gene expression microarray and gene knock-out mouse models provide insight into mechanisms by which cadmium may affect bone. Application of the results to humans is considered with respect to cigarette smoke exposure pathways and direct vs. indirect effects of cadmium. Clearly, understanding the mechanism(s) by which cadmium causes bone loss in experimental animals will provide insight into its diverse effects in humans. Preventing bone loss is critical to maintaining an active, independent lifestyle, particularly among elderly persons. Identifying environmental factors such as cadmium that contribute to increased fractures in humans is an important undertaking and a first step to prevention.
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Arora M, Weuve J, Schwartz J, Wright RO. Association of environmental cadmium exposure with periodontal disease in U.S. adults. ENVIRONMENTAL HEALTH PERSPECTIVES 2009; 117:739-44. [PMID: 19479015 PMCID: PMC2685835 DOI: 10.1289/ehp.0800312] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Accepted: 01/21/2009] [Indexed: 05/23/2023]
Abstract
BACKGROUND Periodontal disease is a complex, multifactorial, chronic inflammatory disease that involves degradation of periodontal structures, including alveolar bone. Cadmium adversely affects bone remodeling, and it is therefore possible that environmental Cd exposure may be a risk factor for periodontal-disease-related bone loss. OBJECTIVE We examined the relationship between environmental Cd exposure and periodontal disease in U.S. adults. METHODS We analyzed cross-sectional data from the third National Health and Nutrition Examination Survey (NHANES III). We defined periodontal disease as clinical attachment loss of at least 4 mm in > 10% of sites examined. We used multivariable-adjusted logistic regression analyses to estimate the association between creatinine-corrected urinary Cd levels and periodontal disease. RESULTS Of the 11,412 participants included in this study, 15.4% had periodontal disease. The age-adjusted geometric mean urine Cd concentration (micrograms per gram creatinine) was significantly higher among participants with periodontal disease [0.50; 95% confidence interval (CI), 0.45-0.56] than among those without periodontal disease (0.30; 95% CI, 0.28-0.31). Multivariable-adjusted analyses, which included extensive adjustments for tobacco exposure, showed that a 3-fold increase in creatinine-corrected urinary Cd concentrations [corresponding to an increment from the 25th (0.18 microg/g) to the 75th (0.63 microg/g) percentile] was associated with 54% greater odds of prevalent periodontal disease (odds ratio = 1.54; 95% CI, 1.26-1.87). We observed similar results among the subset of participants who had limited exposure to tobacco, but only after removing six influential observations. CONCLUSION Environmental Cd exposure was associated with higher odds of periodontal disease.
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Affiliation(s)
- Manish Arora
- Population Oral Health, Faculty of Dentistry, Westmead Centre for Oral Health, University of Sydney, Sydney, New South Wales, Australia.
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In-ovo Cadmium Toxicity in Developing Quail Embryo (Coturnix japonica): Sex-dependent Responses to Ascorbic Acid Protection. J Poult Sci 2009. [DOI: 10.2141/jpsa.46.334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Smith SS, Reyes JR, Arbon KS, Harvey WA, Hunt LM, Heggland SJ. Cadmium-induced decrease in RUNX2 mRNA expression and recovery by the antioxidant N-acetylcysteine (NAC) in the human osteoblast-like cell line, Saos-2. Toxicol In Vitro 2008; 23:60-6. [PMID: 19017541 DOI: 10.1016/j.tiv.2008.10.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 10/13/2008] [Accepted: 10/14/2008] [Indexed: 11/16/2022]
Abstract
Exposure to cadmium poses a threat to human health, including increased susceptibility to developing the bone disease osteoporosis. Despite its recognized importance as an environmental toxin, little is known about how cadmium directly impacts bone-forming osteoblasts. We previously reported that cadmium induces apoptosis in human osteoblast-like Saos-2 cells. In this work, we hypothesize that cadmium exposure induces oxidative stress which leads to decreased RUNX2 mRNA expression and increased apoptotic death, and predict that the antioxidant NAC mitigates the damaging effects of cadmium. Oxidative stress is implicated in osteoporosis; furthermore the osteoblast transcriptional factor RUNX2 is reported to play a protective role against osteoporosis in postmenopausal women. Cells treated with 10 microM CdCl2 exhibited signs of oxidative damage including depletion in glutathione, increased reactive oxygen species formation, and enhanced lipid peroxidation. RUNX2 mRNA expression, by RT-PCR, was significantly reduced after exposure to 10 microM CdCl2. Pretreatment with the antioxidant NAC (1mM) prevented cadmium-induced decrease in RUNX2 mRNA and protected cells from apoptotic death. This study provides insight into the mechanisms underlying cadmium-induced osteotoxicity. In addition, this study distinguishes itself by identifying RUNX2 as a target for heavy metal-induced osteotoxicity.
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Affiliation(s)
- Spenser S Smith
- Department of Biology, The College of Idaho, 2112 Cleveland Blvd., Caldwell, ID 83605, USA
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Nissen-Meyer LSH, Svalheim S, Taubøll E, Reppe S, Lekva T, Solberg LB, Melhus G, Reinholt FP, Gjerstad L, Jemtland R. Levetiracetam, Phenytoin, and Valproate Act Differently on Rat Bone Mass, Structure, and Metabolism. Epilepsia 2007; 48:1850-60. [PMID: 17634065 DOI: 10.1111/j.1528-1167.2007.01176.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Long-term treatment with antiepileptic drugs (AEDs) is associated with increased risk of fractures. Phenytoin (PHT) and valproate (VPA) have both been suggested to influence bone health, whereas levetiracetam (LEV) is scarcely studied. The present study compares the effect of these AEDs on bone mass, biomechanical strength, and bone turnover in rats. METHODS Female rats received PHT (50 mg/kg), VPA (300 mg/kg), or LEV (50 and 150 mg/kg) for 90 days. Dissected femurs were analyzed using dual energy x-ray absorptiometry (DXA), three-point cantilever bending, and histomorphological evaluation. Serum levels of biochemical bone turnover markers were monitored using immunoassay quantification. RESULTS PHT and VPA reduced bone mineral density (BMD) and content (BMC) in one or more bone compartments, whereas LEV did not. VPA induced increased bone turnover, whereas modest changes were observed for PHT. Interestingly, low-dose LEV was associated with reduced biomechanical strength of the femoral neck (mainly trabecular bone). In addition, low-dose LEV treatment resulted in significantly reduced levels of serum osteocalcin, a marker of bone formation. Histomorphological analyses indicated increased retention of cartilage remnants at the growth plate metaphysis of rats treated with low-dose LEV vs. controls. CONCLUSIONS PHT, VPA, and LEV exert differential effects on bone mass and strength, suggesting different mechanisms of action. The weakening effect of low-dose LEV on the femoral neck, despite a constant BMD, suggests a primary effect on bone quality. These findings warrant further human studies of possible adverse effects of LEV on bone development and growth, particularly in children and adolescents.
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Brzóska MM, Rogalska J, Galażyn-Sidorczuk M, Jurczuk M, Roszczenko A, Kulikowska-Karpińska E, Moniuszko-Jakoniuk J. Effect of zinc supplementation on bone metabolism in male rats chronically exposed to cadmium. Toxicology 2007; 237:89-103. [PMID: 17560002 DOI: 10.1016/j.tox.2007.05.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Revised: 04/26/2007] [Accepted: 05/01/2007] [Indexed: 11/22/2022]
Abstract
The aim of the present study is to investigate, based on the rat model of moderate and relatively high human exposure to cadmium (Cd), whether zinc (Zn) supplementation may prevent Cd-induced disorders in bone metabolism. For this purpose, male Wistar rats received Cd (5 and 50mg/l) or/and Zn (30 and 60mg/l) in drinking water for 6 and 12 months. Bone densitometry and biochemical markers of bone turnover were used to assess the effects of Cd or/and Zn. Bone mineral content (BMC) and density (BMD) were measured in the femur. Serum osteocalcin (OC) and alkaline phosphatase in trabecular (bT-ALP) and cortical (bC-ALP) bone were determined as bone formation markers, and carboxy-terminal cross-linking telopeptides of type I collagen (CTX) in serum were measured as bone resorption marker. Serum concentration of calcium (Ca) and its renal handling, as well as Zn and Cd concentrations in the serum/blood, urine and femur were evaluated as well. The exposure to 5 and 50mg Cd/l (0.340+/-0.026 and 2.498+/-0.093mg Cd/kg body wt/24h, respectively), in a dose and duration dependent manner, affected bone turnover (inhibited bone formation and stimulated its resorption) and disturbed bone mineralization (decreased BMC, BMD and Zn concentration). Zn supply at the concentration of 30 and 60mg/l (1.904+/-0.123 and 3.699+/-0.213mg/kg body wt/24h, respectively) during Cd exposure influenced the Cd-induced disorders in bone metabolism. Zn administration to the Cd-exposed rats enhanced the bone ALP activity and prevented Cd-induced bone resorption, but had no statistically significant effect on BMC and BMD; however, mean values of the densitometric parameters in the rats receiving both Cd and Zn were higher than in those treated with Cd alone. Moreover, Zn supplementation at both levels of Cd exposure was found to prevent Cd accumulation in the femur and the Cd-induced decrease in bone Zn concentration. The results of the present study allow the conclusion that Zn supplementation during Cd exposure may partly protect from disorders in bone metabolism. The influence of Zn may be accompanied by its ability to prevent Cd-induced Zn deficiency and to decrease Cd accumulation in bone tissue. The findings seem to indicate that enhanced dietary intake of Zn in subjects chronically exposed to moderate and relatively high Cd levels may have a protective influence on the skeleton.
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Affiliation(s)
- Malgorzata M Brzóska
- Department of Toxicology, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland.
| | - Joanna Rogalska
- Department of Toxicology, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland
| | | | - Maria Jurczuk
- Department of Toxicology, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland
| | - Alicja Roszczenko
- Department of Toxicology, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland
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69
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Coonse KG, Coonts AJ, Morrison EV, Heggland SJ. Cadmium induces apoptosis in the human osteoblast-like cell line Saos-2. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2007; 70:575-81. [PMID: 17365611 DOI: 10.1080/15287390600882663] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Human exposure to the heavy metal cadmium has been associated with the development of bone diseases, including osteoporosis and osteomalacia. The mechanisms by which cadmium exerts a direct effect on bone remain unclear. Bone cells go through apoptosis for proper bone remodeling; therefore, it was hypothesized that cadmium disrupts this normal balance by inducing apoptosis. Human osteoblast-like cells (Saos-2) were treated with 10-200 muM cadmium chloride (CdCl2) and evaluated by trypan blue staining and phase-contrast microscopy. Exposure to CdCl2 resulted in decreased cell viability and changes in cell morphology characteristic of apoptosis. The role of apoptosis in cadmium-induced toxicity was further evaluated using the fluorescent marker annexin V, which detects externalization of cell membrane phosphatidylserine. Nuclear changes associated with apoptosis were assessed by Hoechst staining and a DNA fragmentation assay. A significant increase in annexin V-positive cells was observed following CdCl2 treatment. Nuclear changes associated with apoptosis, including marginalization and condensing of chromatin and DNA fragmentation, were also observed following CdCl2 treatment. Cadmium-induced apoptosis in Saos-2 cells was also accompanied by an increase in caspase-3 activity. The addition of the caspase-3 inhibitor N-acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO) or the known cadmium chelating agent potassium bis(2-hydroxyethy)dithiocarbamate, (K[bhedtc]), blocked caspase-3 activation induced by cadmium. Collectively, this study has identified a role for apoptosis in cadmium-induced toxicity in bone cells, and provides insight for future studies on mechanisms underlying the disruption of apoptotic signaling cascades in bone and the relationship to bone disease.
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Affiliation(s)
- K G Coonse
- Department of Biology, Albertson College of Idaho, Caldwell, Idaho 83605, USA
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70
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Haron S, Ray AK. Optical biodetection of cadmium and lead ions in water. Med Eng Phys 2006; 28:978-81. [PMID: 17018258 DOI: 10.1016/j.medengphy.2006.04.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Accepted: 04/28/2006] [Indexed: 11/24/2022]
Abstract
A three layer waveguiding silicon dioxide (SiO(2))/silicon nitride (Si(3)N(4))/SiO(2) structure on silicon substrate was proposed as an optically efficient biosensor for calibration of heavy metal ions in drinking water. The catalytic activities of urease and acetylcholine esterase (AchE) were inhibited by the presence of cadmium (Cd(2+)) and lead (Pb(2+)) ions. The detection limit as low as 1 ppb was achieved by employing the technique of total reflection at the interface between the Si(3)N(4) core and composite polyelectrolyte self-assembled (PESA) membranes containing cyclotetrachromotropylene (CTCT) as an indicator.
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Affiliation(s)
- Saharudin Haron
- Department of Chemical Engineering, Faculty of Chemical and Natural Resources Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia
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71
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Akesson A, Bjellerup P, Lundh T, Lidfeldt J, Nerbrand C, Samsioe G, Skerfving S, Vahter M. Cadmium-induced effects on bone in a population-based study of women. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:830-4. [PMID: 16759980 PMCID: PMC1480481 DOI: 10.1289/ehp.8763] [Citation(s) in RCA: 232] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2005] [Accepted: 02/02/2006] [Indexed: 05/03/2023]
Abstract
High cadmium exposure is known to cause bone damage, but the association between low-level cadmium exposure and osteoporosis remains to be clarified. Using a population-based women's health survey in southern Sweden [Women's Health in the Lund Area (WHILA) ] with no known historical cadmium contamination, we investigated cadmium-related effects on bone in 820 women (53-64 years of age) . We measured cadmium in blood and urine and lead in blood, an array of markers of bone metabolism, and forearm bone mineral density (BMD) . Associations were evaluated in multiple linear regression analysis including information on the possible confounders or effect modifiers: weight, menopausal status, use of hormone replacement therapy, age at menarche, alcohol consumption, smoking history, and physical activity. Median urinary cadmium was 0.52 microg/L adjusted to density (0.67 microg/g creatinine) . After multivariate adjustment, BMD, parathyroid hormone, and urinary deoxypyridinoline (U-DPD) were adversely associated with concentrations of urinary cadmium (p < 0.05) in all subjects. These associations persisted in the group of never-smokers, which had the lowest cadmium exposure (mainly dietary) . For U-DPD, there was a significant interaction between cadmium and menopause (p = 0.022) . Our results suggest negative effects of low-level cadmium exposure on bone, possibly exerted via increased bone resorption, which seemed to be intensified after menopause. Based on the prevalence of osteoporosis and the low level of exposure, the observed effects, although slight, should be considered as early signals of potentially more adverse health effects. Key words: biochemical bone markers, bone mineral density, cadmium, lead, osteoporosis, women.
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Affiliation(s)
- Agneta Akesson
- Division of Metals and Health, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
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Affiliation(s)
- Takashi Umemura
- Laboratory of Comparative Pathology, Hokkaido University Graduate School of Veterinary Medicine
| | - Yumi Wako
- Kashima Laboratory of Mitsubishi Chemical Safety Institute Ltd
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Brzóska MM, Moniuszko-Jakoniuk J. Bone metabolism of male rats chronically exposed to cadmium. Toxicol Appl Pharmacol 2005; 207:195-211. [PMID: 16129113 DOI: 10.1016/j.taap.2005.01.003] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 12/22/2004] [Accepted: 01/05/2005] [Indexed: 11/16/2022]
Abstract
Recently, based on a female rat model of human exposure, we have reported that low-level chronic exposure to cadmium (Cd) has an injurious effect on the skeleton. The purpose of the current study was to investigate whether the exposure may also affect bone metabolism in a male rat model and to estimate the gender-related differences in the bone effect of Cd. Young male Wistar rats received drinking water containing 0, 1, 5, or 50 mg Cd/l for 12 months. The bone effect of Cd was evaluated using bone densitometry and biochemical markers of bone turnover. Renal handling of calcium (Ca) and phosphate, and serum concentrations of vitamin D metabolites, calcitonin, and parathormone were estimated as well. At treatment with 1 mg Cd/l, corresponding to the low environmental exposure in non-Cd-polluted areas, the bone mineral content (BMC) and density (BMD) at the femur and lumbar spine (L1-L5) and the total skeleton BMD did not differ compared to control. However, from the 6th month of the exposure, the Z score BMD indicated osteopenia in some animals and after 12 months the bone resorption very clearly tended to an increase. The rats' exposure corresponding to human moderate (5 mg Cd/l) and especially relatively high (50 mg Cd/l) exposure dose- and duration-dependently disturbed the processes of bone turnover and bone mass accumulation leading to formation of less dense than normal bone tissue. The effects were accompanied by changes in the serum concentration of calciotropic hormones and disorders in Ca and phosphate metabolism. It can be concluded that low environmental exposure to Cd may be only a subtle risk factor for skeletal demineralization in men. The results together with our previous findings based on an analogous model using female rats give clear evidence that males are less vulnerable to the bone effects of Cd compared to females.
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Affiliation(s)
- Malgorzata M Brzóska
- Department of Toxicology, Medical University of Bialystok, Mickiewicza 2C, 15-222 Bialystok, Poland.
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Brzóska MM, Moniuszko-Jakoniuk J. Effect of low-level lifetime exposure to cadmium on calciotropic hormones in aged female rats. Arch Toxicol 2005; 79:636-46. [PMID: 15940469 DOI: 10.1007/s00204-005-0680-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Accepted: 04/19/2005] [Indexed: 10/25/2022]
Abstract
The effect of low-level lifetime exposure to cadmium (Cd) on calciotropic hormones and the possible association between the Cd-induced disorders in bone metabolism and these hormones were investigated on a female rat model of human environmental exposure in areas unpolluted by this metal. For this purpose, the concentrations of 25-hydroxyvitamin D (25OHD), 1,25-dihydroxyvitamin D (1,25(OH)(2)D), calcitonin (CT) and parathormone (PTH) were measured in the serum of control and Cd-exposed (1 mg Cd/l in drinking water for 24 months) female rats. Calcium (Ca) and inorganic phosphorus (P(i)) serum concentrations, renal tubular reabsorption of Ca (TRCa) and phosphate (TRP) and the glomerular filtration rate (GFR) were estimated as well. Moreover, 1,25(OH)(2)D, metallothionein (MT) and Cd were determined in the kidney. The exposure to Cd led to a decrease in the serum concentrations of 25OHD and 1,25(OH)(2)D (by 50 and 31%, respectively) and the concentration of 1,25(OH)(2)D in the kidney mitochondrial fraction (by 55%). The serum concentrations of CT and PTH increased (5.2-fold and by 29%, respectively) and those of Ca and P(i) were unchanged, whereas the TRCa, TRP and GFR decreased due to the exposure to Cd. The results give evidence that the low lifetime exposure to Cd disturbs the metabolism of calciotropic hormones and damages the reabsorptive and filtrative function of the kidney in aged female rats. Numerous correlations noted between calciotropic hormones and the indices of kidney function, and indices of bone turnover and bone mineral status (bone mineral content and density) of these females indicate a relationship between these hormones and the kidney functional status and bone metabolism. The results of the present study together with our previous findings on the bone status in the experimental model allow for the conclusion that the low lifetime exposure to Cd by affecting the metabolism and proper function of calciotropic hormones may contribute to the advancement of bone damage at the elderly.
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Affiliation(s)
- Malgorzata M Brzóska
- Department of Toxicology, Medical University of Bialystok, Mickiewicza 2c, 15-222 Bialystok, Poland.
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