Association of blood heavy metal levels with osteocalcin abnormality and incidence of osteoporosis in Saudi subjects

Serum toxic metals have been implicated in development of many diseases. This study investigated the association between blood levels of lead and cadmium with abnormal bone mineral density (BMD) and incidence of osteoporosis. Sixty Saudi male adults age matching were assigned into two groups: A healthy control group (n = 30) and osteoporosis patients diagnosed according to T-score (n = 30). Serum calcium, vitamin D, osteocalcin, lead, cadmium were measured. Osteoporotic group showed a highly significant elevation of blood lead and cadmium levels compared to the control group (p <0.001). BMD was negatively correlated with serum osteocalcin level compared with control. There was a significant negative correlation between the cadmium and lead levels (r=-0.465 and p-value = 0.01) and calcium (p < 0.004). Our findings suggested that high cadmium and lead were negative correlated to BMD and increased the risk factor for osteoporosis.

β-Synuclein: An Enigmatic Protein with Diverse Functionality

α-Synuclein (αS) is a small, unstructured, presynaptic protein expressed in the brain. Its aggregated form is a major component of Lewy bodies, the large proteinaceous deposits in Parkinson’s disease. The closely related protein, β-Synuclein (βS), is co-expressed with αS. In vitro, βS acts as a molecular chaperone to inhibit αS aggregation. As a result of this assignation, βS has been largely understudied in comparison to αS. However, recent reports suggest that βS promotes neurotoxicity, implying that βS is involved in other cellular pathways with functions independent of αS. Here, we review the current literature pertaining to human βS in order to understand better the role of βS in homeostasis and pathology. Firstly, the structure of βS is discussed. Secondly, the ability of βS to (i) act as a molecular chaperone; (ii) regulate synaptic function, lipid binding, and the nigrostriatal dopaminergic system; (iii) mediate apoptosis; (iv) participate in protein degradation pathways; (v) modulate intracellular metal levels; and (vi) promote cellular toxicity and protein aggregation is explored. Thirdly, the P123H and V70M mutations of βS, which are associated with dementia with Lewy bodies, are discussed. Finally, the importance of post-translational modifications on the structure and function of βS is reviewed. Overall, it is concluded that βS has both synergistic and antagonistic interactions with αS, but it may also possess important cellular functions independent of αS.

Climate change extreme and seasonal toxic metal occurrence in Romanian freshwaters in the last two decades—case study and critical review

The relationship between metal levels in the Olt River ecosystem in southern Romania (measured during 2018‒2019, with 1064 sediment and water samples) and daily climate data were explored to assess the need for targeted source identification and mitigation strategies. In 2018, there was a strong relationship between the sediment Pb, As, Cd, and Hg contents and temperature (r > 0.8, p < 0.001). Mercury in sediments had a positive correlation with precipitation, and Hg in the water correlated with minimum temperature in May 2018 (p < 0.01). In July 2019, heavy metals were positively correlated with precipitation and negatively correlated with temperature. According to nonsymmetrical correspondence analysis, the four climate parameters analyzed were linearly correlated with the frequency of metal detection (p < 0.001) in both years. The statistical analysis showed strong relationships between heavy metal levels and climatic factors and attributed the discrepancies in elemental concentrations between 2018 and 2019 to climate warming.

Assessment of Heavy Metals in Agricultural Soils and Plant (Vernonia amygdalina Delile) in Port Harcourt Metropolis, Nigeria

This study assessed the concentration of heavy metal, such as lead (Pb), cadmium (Cd), Chromium (Cr), iron (Fe), Nickel (Ni), and Silver (Ag), in Vernonia amygdalina Delile and agricultural soils of three university farms located in Port Harcourt, Nigeria. The soils and plants were taken randomly to form composite samples and analyzed for heavy metals by the use of atomic absorption spectroscopy (AAS) and X-ray fluorescence (XRF). The study stations were agricultural soils and Vernonia amygdalina Delile from the Ignatius Ajuru University of Education (I), River State University (R) and University of Port Harcourt (U). The soil samples recorded mean concentration ranges for Fe as 19.71 ± 1.77 (I)–27.24 ± 3.56 mg/kg (R) in soils and 12.95 ± 1.68 (R)–18.18 ± 2.02 mg/kg (U) for the bitter leaf samples. The mean range for Pb concentration in the soil and bitter leaf were 4.35 ± 0.87–6.80 ± 0.86 mg/kg and 0.24 ± 0.64–2.19 ± 0.74 mg/kg, while Cd concentration in the soil and bitter leaf were 0.46 ± 0.28–1.42 ± 0.40 mg/kg and 0.17 ± 0.22–0.42 ± 0.08 mg/kg, respectively. The respective mean ranges for Cr concentration in the soil and bitter leaf were 5.91 ± 1.14–8.77 ± 0.88 mg/kg and 4.04 ± 0.64–5.92 ± 0.69 mg/kg, while Ni in soil and bitter leaf were 0.54 ± 3.38–10.26 ± 3.50 mg/kg and 0.042 ± 1.42–3.30 ± 0.88 mg/kg, while Ag was negligible. Heavy metal levels in soils and Vernonia amygdalina followed the order Fe > Cr > Pb > Ni > Cd and Fe > Cr > Ni > Pb > Cd, respectively, and were lower than WHO/FAO and EPA, except Cd, which was higher in soil and in Vernonia amygdalina. The ecological risk factor (ErF) was comparatively lower in soils than in the plant, while pollution load index (PLI) showed high heavy metal retention capacities in Vernonia amygdalina due to more anthropogenic influences. The metal transfer factor (TF) was highest in Fe, followed by Cr > Cd > Ni > Pb, while Pb had the highest chances of cancer risks from the incremental lifetime cancer risk (ILCR), especially in both soil and plant (mean ILCR, 2.07 × 10−2 and 2.45 × 10−3), while Cd had the least (mean ILCR, 9.64 × 10−5 and 3.36 × 10−5). Anthropogenic activities must be regulated and monitored by government relevant agencies to reduce heavy metal inputs into soils and avoid excessive accruals in food chain.

Spatial Variation of Trace Metals between Industrial and Rural Dwelling Birds of India

A large quantity of trace metals has been continuously polluting the environment as a result of increasing urbanization and industrial processes. In 2016-2017, the metal (Cd, Cu, Cr, Ni, Pb, and Zn) levels were determined in fecal pellets of Blue Rock Pigeon (Columba livia) at Bais Godam (industrial location) in Jaipur and Chittora (rural location) in Rajasthan, India. Fecal pellets in industrial regions which are under higher anthropogenic influence exhibited higher metal concentrations when compared with the fecal pellets of the same species in rural area which have minimal anthropogenic input, with statistically significant industrial-rural differences in the metal concentrations except for Ni. Results obtained in this study, as well as the comparison with literature data, indicated that concentrations of Cr and Cu were high in fecal pellets of Blue Rock Pigeon in the industrial region of the present study. Furthermore, many significant correlations were also observed between metal levels in the industrial region which could be attributed to a similar source. Moreover, contamination levels of pigeon excrement serve as one of the most compelling indicators in terrestrial systems for the monitoring of metal pollution levels.

Protein Expression in the Gastrocnemius Muscle of a Rodent Shrapnel-Injury Model

With shrapnel injuries, the metal fragment is usually left in place to reduce the risk of morbidity extensive surgery might bring. This means the individual may retain those metals for the remainder of their life. Often the long-term health effects of the embedded metal are not known, especially with respect to protein damage and perturbations of muscle repair pathways. In this study, using homogenates of rat gastrocnemius muscle implanted with pellets of military-relevant metals, we investigated expression of iNOS and eNOS, enzymes involved in nitric oxide production, as well as MMP-2 and MMP-9, matrix metalloproteinases associated with muscle repair. In addition, hydroxynonenal-modified proteins were investigated to assess metal-induced oxidative damage and metal levels in the gastrocnemius determined. Metals were implanted for up to 12 months in order to determine the long-term effects on the expression of muscle-associated proteins. With the exception of iron and cobalt at 1-month post-implantation, there were no significant differences in metal levels in the gastrocnemius in any of the cohorts. Protein expression analysis showed significant decreases in iNOS and eNOS in the 6-month and 12-month lead and depleted uranium groups. Hydroxynonenal-modified proteins were also significantly increased in the iron, copper, lead, and depleted uranium groups. These results suggest that some embedded metals can induce long-term oxidative damage, as well as affect enzyme systems involved in signal transduction.