Tissue Zinc Concentrations Research Articles

Zinc Supplementation Attenuates Metallothionein and Oxidative Stress Changes in Kidney of Streptozotocin-Induced Diabetic Rats

Zinc is an element that under physiological conditions preferentially binds to and is a potent inducer of metallothionein under physiological conditions. The present study was conducted to explore whether zinc supplementation morphologically and biochemically protects against diabetic nephropathy through modulation of kidney metallothionein induction and oxidative stress in streptozotocin-induced diabetic rats. Thirty-two Wistar albino male rats were equally divided into four groups. The first group was used as untreated controls and the second group was supplemented with 30mg/kg/day zinc as zinc sulfate. The third group was treated with streptozotocin to induce diabetes and the fourth group was treated with streptozotocin and supplemented with zinc as described for group 2. The blood glucose and micro-albuminuria levels, body and kidney weights were measured during the 42-day experimental period. At the end of the experiment, the kidneys were removed from all animals from the four groups. Diabetes resulted in degenerative kidney morphological changes. The metallothionein immunoreactivity level was lower and the kidney lipid peroxidation levels were higher in the diabetes group than in the controls. The metallothionein immunoreactivity levels were higher in the tubules of the zinc-supplemented diabetic rats as compared to the non-supplemented diabetic group. The zinc and metallothionein concentrations in kidney tissue were higher in the supplemented diabetic group compared to the non-supplemented diabetes group. The activity of glutathione peroxidase did not change in any of the four groups. In conclusion, the present study shows that zinc has a protective effect against diabetic damage of kidney tissue through stimulation of metallothionein synthesis and regulation of the oxidative stress.

Evaluation of zinc tolerance and accumulation potential of the coastal shrub Limoniastrum monopetalum (L.) Boiss.

The coastal shrub Limoniastrum monopetalum is capable of growth in soil containing extremely high concentrations of heavy metals. A greenhouse experiment was conducted in order to investigate the effects of a range of Zn concentrations (0–130mmoll−1) on growth and photosynthetic performance, by measuring relative growth rate, total leaf area, plant height, gas exchange, chlorophyll fluorescence parameters and photosynthetic pigment concentrations. We also determined the total zinc, nitrogen, phosphorus, sulphur, calcium, magnesium, sodium, potassium, iron and copper concentrations in the plant tissues. The study species demonstrated hypertolerance to Zn stress, since survival was recorded with leaf concentrations of up to 1700mgZnkg−1 dry mass when treated with 130mmolZnl−1. L. monopetalum exhibited little overall effects on photosynthetic function at Zn levels of up to 90mmoll−1. At greater external Zn concentration, plant growth was negatively affected, due in all probability to the recorded decline in net photosynthetic rate, which may be linked to the adverse effect of the metal on photosynthetic electron transport. Growth parameters were virtually unaffected by leaf tissue concentrations as high as 1400mgZnkg−1 dry mass thus indicating that this species could play an important role in the phytoremediation of Zn-polluted areas.

Determination of Metal (Cu, Zn, Se, Cr and Cd) Levels in Tissues of the Cyprinid Fish, Capoeta trutta (Heckel, 1843) from Different Regions of Keban Dam Lake (Euphrates-Turkey)

The aim of this study was to evaluate Copper (Cu), Zinc (Zn), Selenium (Se), Chromium (Cr) and Cadmium (Cd) concentrations in liver, muscle, gills and kidney tissues of Capoeta trutta collected from four sites of Keban Dam Lake, Turkey. The highest heavy metal level in all tissues was for Zn, while Cd was the lowest. The lowest heavy metal levels were generally found at Station 4 (Agin) for all tissues (p<0.05). There were statistically significant differences among stations for Cu, Zn, Cr and Se in gills; for Cu, Zn, Se and Cr in liver and kidney; and Cu, Zn and Cr in muscle (p<0.05). Cadmium concentrations did not differ between sites for any of the tissues. Turkish Food Codex sets the maximum limits of Zn, Cu and Cd as, 50, 20 and 0.05mgkg(-1) dry weight, respectively, in the muscle of fish used for human consumption. In our study, the level of Zn was higher than Turkish permissible limits only at Station 3 (Guluskur). Cadmium levels were much higher than permissible limits at three stations [S1 (Pertek), S2 (Kockale) and S3], whereas Cu levels were within permissible limits in all stations.

Cadmium and Zinc Concentrations in Soils and Oil Palm Tissues as Affected by Long-Term Application of Phosphate Rock Fertilizers

The study was conducted to determine Cd and Zn concentrations in soils with three different ages of oil palm trees (<10, >15, >20 years) and plant parts as affected by long-term application of phosphate rock fertilizers. To investigate this issue on Malaysia's oil palm plantations, six soil series that undergo a scheduled fertilizer program were collected. Jawa, Selangor, and Sedu Series were selected from a plantation in the coastal area, whilst Munchong, Rengam, and Segamat Series were collected from a plantation in the inland area. Fronds and fruitlets were also collected along with the soils (paired sampling). To verify the findings of the field study, Cd and Zn adsorption isotherms were prepared. Competitive adsorption between Zn and Cd was also conducted. There was no accumulation of Cd in all the soil series but Zn accumulated in the Selangor and Segamat Series. Fruitlets (edible part) show no increase in Cd and Zn concentrations, but Jawa and Selangor Series show increasing values of Zn concentrations in the fronds. A correlation study reveals that soil pH and clay content were the soil properties that controlled Cd and Zn concentrations in soils. Cadmium in soils and soil solutions most probably contributed to the Cd concentrations in fruitlets, whereas Cd and Zn in soils may influence the uptake of these elements by the oil palm trees. The highest Cd and Zn accumulation in Segamat Series Soil had been shown in the adsorption isotherm study. Cadmium adsorption was decreased in the presence of Zn, leading to no accumulation of Cd in all the soil series.

Dolomite Phosphate Rock–Based Slow-Release Fertilizer for Agriculture and Landscapes

Most soils in Florida are very sandy, and water-soluble fertilizers (WSF) are subjected to leaching loss. Alternate fertilization is a promising practice to reduce such loss. Dolomite phosphate rock (DPR), which contains calcium, magnesium, and phosphorus, is potentially useful for agricultural production and landscaping plants. In this study, DPR fertilizers were developed from mixing of DPR material and N-viro soil. A typical agricultural soil (Alfisol) in Florida was used for greenhouse studies, and ryegrass and citrus seedlings were tested. The DPR fertilizers appeared superior to WSF for the growth of ryegrass based on dry-matter yield and nutrient concentrations in plant; however, it was not evident in citrus seedlings. DPR fertilizers were effective in raising pH (by 3 units) and electrical conductivity of acidic sandy soils and increasing soil organic matter, total nutrients, and available nutrients. The concentrations of copper, lead, and zinc in the plant tissues were less than toxicity limits.

Synthesis and characterization of ZnS:Mn/ZnS core/shell nanoparticles for tumor targeting and imaging in vivo

Fluorescence imaging technique has been used for imaging of biological cells and tissues invivo. The Cd-free luminescent quantum dots conjugating with a cancer targeting ligand has been taken as a promising biocompatibility and low cytotoxicity system for targeted cancer imaging. This work reports the synthesis of fluorescent-doped core/shell quantum dots of water-soluble manganese-doped zinc sulfide. Quantum dots of manganese-doped zinc sulfide were prepared by nucleation doping strategy, with 3-mercaptopropionic acid as stabilizer at 90 in aqueous solution. The manganese-doped zinc sulfide nanoparticles exhibit strong orange fluorescence under UV irradiation, resistance to photo-bleaching, and low-cytotoxicity to HeLa cells. The structure and optical properties of nanoparticles were characterized by scanning electron microscope, X-ray diffraction, dynamic light scattering, and photoluminescence emission spectroscopy. Manganese-doped zinc sulfide nanoparticles conjugated with folic acid using 2,2'-(ethylenedioxy)-bis-(ethylamine) as the linker. The covalent binding of both 2,2'-(ethylenedioxy)-bis-(ethylamine) and folic acid on the surface of manganese-doped zinc sulfide nanoparticles probed by Fourier transform infrared spectroscopy detection. Furthermore, invitro cytotoxicity assessment of manganese-doped zinc sulfide-folic acid probes use HeLa cells. The obtained fluorescent probes (manganese-doped zinc sulfide) were used for tumor targeting and imaging invivo. The manganese-doped zinc sulfide-folic acid fluorescent probes which targeting the tumor cells in the body of nude mouse tumor model would emit orange fluorescence, when exposed to a 365 nm lamp. We investigate the biodistribution of the manganese-doped zinc sulfide-folic acid fluorescent probes in tumor mouse model by measuring zinc concentration in tissues. These studies demonstrate the practicality of manganese-doped zinc sulfide-folic acid fluorescent probes as promising platform for tumor targeting and imaging invivo.

Zinc concentration in different tissues of infected mice with Giardia intestinalis

It is well recognized the association of giardiasis with malnutrition and micronutrients malabsorption, but the link giardiasis caused by Giardia intestinalis with low serum zinc levels in children remains controversial. The lack of knowledge on the adequate zinc levels in different human tissues may is contributing to the poor understanding of the mentioned link. Therefore, the assessment of the association between zinc content in different tissues of Giardia ‐infected mice may provides new knowledge about the interaction giardiasis‐zinc in humans. To assess and to associate the zinc content in tissues of the small intestine, liver, kidneys, testes, long bones and serum of Giardia‐infected mice. Seventy two CD1 mice were randomly categorized (males 4–5 weeks) based on the dietary zinc requirements (low, 12.8 Zn mg/kg diet; normal, 24.6 Zn mg/kg; high, 57.9 Zn mg/kg and very high, 309.3 Zn mg/kg) (groups of n=20, n=20, n=20, n=12). Subsequently half of each group was categorized in Giardia‐infected and Giardia‐free groups (6 groups of n=10 and 2 groups of n=6). The tissue samples were obtained at 0 and 30 days post‐infection. Zinc concentrations were determined by atomic absorption. All statistical analysis were performed using NCSS (2002) at level of α= 0.05%.. Giardiasis had a negative effect on zinc concentrations in serum, testes, kidney, small intestine and long bones (p &lt; 0.05) at 30 days post‐infection. However, no change was found in the liver tissue (p &gt; 0.05). Zinc homeostasis apparently plays a key role in regulating the zinc tissue contents in mice, despite of the low dietary zinc. In addition, giardiasis was a risk factor associated to the low zinc content in different mice tissue

Evaluation of iron, zinc, and copper levels in pterygium tissue

To determine the concentration of the trace elements iron, copper, and zinc in pterygium tissue and healthy conjunctiva tissue and to investigate the involvement of these elements in pterygium etiopathogenesis. Twenty patients with pterygium were enrolled in the study. The pterygium was excised and a conjunctival rotational flap or autograft inserted. Normal conjunctiva tissue was obtained from the flap or graft. The concentrations of iron, zinc, and copper in the pterygium and conjunctiva tissues were determined by atomic absorption spectrometry after microwave digestion. Iron, zinc, and copper levels were significantly higher in the pterygium tissue than in the normal conjunctiva (P < 0.001). The mean iron, zinc, and copper concentrations in the pterygium tissue were 819, 214, and 3.40 μg/g, whereas the mean concentrations of these elements in the control tissue were 491, 148, and 2.19 μg/g, respectively. Pterygium is a fibrovascular proliferative disorder and elevated levels of trace elements in pterygium tissue may play a pathogenic role via oxidative damage.

Effects of zinc on growth performance and biochemical parameters of piglets

The effects of zinc on growth performance, activities of enzymes, and concentrations of hormones were investigated in this study. Crossbred (Duroc × Landrace × Large White) piglets (initial body weight: 26.66 ± 2.45 kg) were randomly assigned into 4 groups receiving a basal diet and were supplemented with 60, 300, 1000, or 3000 mg/kg of zinc (as ZnSO_4^.7H_2O). The results showed that supplementation of zinc at 3000 mg/kg increased (P < 0.05) the average daily feed intake, weight gain, gain/feed, and relative organ weight, and promoted the activities of alkaline phosphatase and Cu-Zn superoxide (P < 0.05) by 84.17% and 49.86%, respectively, when compared with the control group. It also led to higher hepatic metallothionein content and tissue zinc concentration (P < 0.05) than in the control group. Furthermore, the concentrations of insulin and neuropeptide Y (NPY) in the 3000 mg/kg group were increased (P < 0.05) by 55.19% and 26.53%, respectively, compared to the control group. The present study suggests that pharmacological dietary supplementation of zinc increased growth performance, activities of enzymes, tissue zinc concentrations, and plasma insulin and NPY concentrations. Key words: Zinc, growth performance, tissue zinc concentration, enzyme activity, hormone concentration, piglet

Monitoring of risk metals in chub (Leuciscus cephalus L.) from the Svitava and Svratka rivers in the urban area of Brno, Czech Republic

The aim of this study was to assess the impact of the Brno agglomeration on the distribution of risk elements (Pb, Cd, Cu, Zn, As) in tissues of a total of 50 chub (Leuciscus cephalus L.). Contamination by metals was monitored in fish from different sites on the Svitava and Svratka rivers in the urban agglomeration of Brno in 2008. Metal concentration was determined in the muscle, liver and kidney by high-resolution atomic absorption spectrometry. Electrothermic technique was used to assess lead, cadmium and copper concentrations; zinc content was determined by flame technique and arsenic by hydride generation. The highest concentrations of cadmium, lead, arsenic and zinc in individual tissues, ranked in a descending order as follows: kidney &gt; liver &gt; muscle; for copper it was liver &gt; kidney &gt; muscle. The highest concentrations of cadmium, arsenic and zinc were determined in chub kidney from the locality of Kníničky (1.35 ± 0.97, 0.186 ± 0.076, and 299.7 ± 123.4 mg·kg-1 respectively); the highest concentration of lead was on the Svratka before junction (0.28 ± 0.19 mg·kg-1). The highest contamination with risk metals was found in chub from the Svratka. The assessed concentrations have shown minimum participation of the Brno agglomeration in the accumulation of metals. The concentrations of all risk elements in chub from all of the monitored localities do not pose any environmental or health threat. This study updates published data on chub from the Rivers Svitava and Svratka on concentration of risk elements.

Enhancement of Methane Production by Codigestion of Dairy Manure with Aquatic Plant Biomass

Codigestion of manures with plant wastes is a promising strategy to increasing methane production during anaerobic digestion. Aquatic plant biomass has the potential to serve as a common, plentiful, and free source of plant matter for anaerobic digestion of animal livestock wastes. In batch anaerobic digesters at 35C, addition of 2% to 3% duckweed significantly increased methane production. Enhancement of methane production was greater than that expected from an increase in feedstock carbon or change in C:N ratio. Analysis of macro- and micronutrient concentrations in duckweed tissues indicated that methane production in batch digesters with 2% duckweed was correlated to tissue concentrations of zinc, sodium, and sulfur and (to a lesser extent) calcium and potassium. Increases in methane production for codigestion of dairy manures with 2% duckweed were also observed at 15C, 25C, and 30C, with the greatest enhancement at 25C.

Zinc tolerance and accumulation in the salt-marsh shrub Halimione portulacoides

The halophytic shrub Halimione portulacoides is known to be capable of growth in soils containing extremely high concentrations of Zn. This study evaluated in detail the tolerance and accumulation potential of H. portulacoides under moderate and high external Zn levels. A greenhouse experiment was conducted in order to investigate the effects of a range of Zn concentrations (0–130mmolL−1) on growth and photosynthetic performance by measuring relative growth rate, total leaf area, specific leaf area, gas exchange, chlorophyll fluorescence parameters and photosynthetic pigment concentrations. We also determined the total zinc, nitrogen, phosphorus, calcium, magnesium, sodium, potassium, iron and copper concentrations in the plant tissues. H. portulacoides demonstrated hypertolerance to Zn stress, since it survived with leaf concentrations of up to 2300mgZnkg−1dry mass, when treated with 130mmolZnL−1. Zinc concentrations greater than 70mmolL−1 in the nutrient solution negatively affected plant growth, in all probability due to the recorded decline in net photosynthesis rate. Our results indicate that the Zn-induced decline in the photosynthetic function of H. portulacoides may be attributed to the adverse effect of the high concentration of the metal on photosynthetic electron transport. Growth parameters were virtually unaffected by leaf tissue concentrations as high as 1500mgZnkg−1dry mass, demonstrating the strong capability of H. portulacoides to protect itself against toxic Zn concentrations. The results of our study indicate that this salt-marsh shrub may represent a valuable tool in the restoration of Zn-polluted areas.

The bioavailability of different chemical forms of zinc in fattening lambs

Abstract. The aim of the presented study was an estimation of the zinc bioavailability derived from amino acid complexes with methionine, lysine and glycine in growing lambs. 48 lambs, Polish Merino × Romanowski × Charolaise crossbreed, at age about 10 weeks and average body weight of 20 kg were randomly divided into 4 experimental groups. Animals were kept collectively and fed with concentrate and hay in amount: 0.7–1.2 and 0.3–0.5 kg/day/head, respectively. After rearing period 6 rams from each group with average body weight of about 30 kg were divided into digestibility-balance experiments. At the end of the experiment the blood samples were taken, then from each group 8 lambs were chosen, killed and during dissection tissue samples were taken (liver, pancreas, kidney and rib bone). In tissue samples as well as in fodders and excrements the content of zinc was determined. Obtained data in digestibility experiments allowed on calculation of apparent absorption and retention of zinc and the level of Zn determined in tissues’ samples were used to the estimation of bioavailability of zinc from different ones applied in experiment sources. Apparent absorption and retention of zinc were higher (P≤0.01) in lambs receiving in mixtures amino acid complexes of zinc than in animals from the control group. The higher content of zinc in soft and hard tissues of lambs which received organic forms of zinc might indicate better assimilation and bioavailability of zinc from these forms than from oxide. Among tested organic forms of zinc, the zinc-lysine complex was characterized as having the most advantageous property.

Zinc as an Appetite Stimulator - The Possible Role of Zinc in the Progression of Diseases Such as Cachexia and Sarcopenia

Zinc is required by humans and animals for many physiological functions, such as growth, immune function, and reproduction. Zinc deficiency induces a number of physiological problems, including anorexia, growth retardation, dermatitis, taste disorder, and hypogonadism. Although it is clear that zinc deficiency produces specific and profound anorexia in experimental animals, the connection between zinc deficiency and anorexia is less certain. We were the first to show that orally, but not intraperitoneally, administered zinc rapidly stimulates food intake through orexigenic peptides coupled to the afferent vagus nerve using rats during early-stage zinc deficiency without decreased zinc concentrations in plasma and tissues. We confirmed that a zinc-sufficient diet containing zinc chloride acutely stimulated food intake after short-term zinc deprivation. We also found that orally administered zinc sulfate increased the expression of NPY and orexin mRNA after administration. Using vagotomized rats, we tested whether the increase in food intake after oral administration of zinc was mediated by the vagus nerve. In sham-operated rats, the oral administration of zinc stimulated food intake, whereas zinc and saline administrations did not exhibit differing effects in vagotomized rats. We conclude that zinc stimulates food intake in short-term zinc-deficient rats through the afferent vagus nerve with subsequent effects on hypothalamic peptides associated with food intake regulation. In this review, we describe recent research investigating the roles of zinc as an appetite stimulator in food intake regulation, along with research about hypothalamus, ghrelin, leptin and zinc receptor, and clinical application about anorexia nervosa, cachexia and sarcopenia. The article also presents some promising patents on zinc.

Assessment of zinc deficiency and effect of dietary carrot, amchur and onion on zinc status during repletion in zinc‐deficient rats

Food acidulants, β-carotene-rich vegetables and sulfur compound-rich Allium spices are known to improve zinc bioaccessibility from food grains. This animal study evaluated the positive influence of these promoters of zinc bioaccessibility on zinc status during zinc repletion in Wistar rats previously rendered zinc-deficient by feeding a zinc-deficient semi-synthetic diet for 4 weeks. Groups of these zinc-deficient animals were subsequently maintained on a zinc-containing grain-based diet for 2 weeks. Various experimental diets consisted of the grain-based diet supplemented with (1) carrot, (2) onion, (3) amchur, (4) carrot + amchur and (5) onion + amchur. Zinc deficiency was confirmed by lower zinc concentration in tissues and bones and lower activity of zinc-containing enzymes. Zinc concentration was 10-15% lower in serum, liver and kidney of zinc-deficient rats. Bone weight in zinc-deficient rats was 20% lower than that in normal rats. Activities of zinc-containing enzymes (hepatic superoxide dismutase and alcohol dehydrogenase and serum alkaline phosphatase) were lower in the zinc-deficient group. Animals fed diets supplemented with these promoters of zinc bioaccessibility showed better zinc status in tissues and bones compared with those repleted with the control stock diet. This animal study supports the claim of promoters of zinc bioaccessibility for improving zinc status, which may find practical application.

Boron application improves on yield and chemical composition of strawberry

Boron (B) is an essential micronutrient required for normal plant growth and development. Boron management is challenging because the optimum B application range is narrow and the application rates vary from one soil to another. Boron deficiency is widespread in the Anatolia region of Turkey. This may impact on yield and mineral contents of leaves and fruits of strawberry (Fragaria×ananassa cv. Fern) especially in B-deficient calcareous Aridisols in Eastern Anatolia, Turkey. A 2-year field experiment was conducted to study yield and quality response of strawberry to B application. Boron fertilizer application affected plant yield and chemical composition. B application decreased tissue nitrogen (N) and calcium (Ca) but increased tissue phosphorus (P), potassium (K), manganese (Mn), zinc (Zn) and copper (Cu) content. We conclude that a B addition of 5.5 kg ha−1 is sufficient to elevate soil B levels to non-deficient levels.

Prostate cancer outcome and tissue levels of metal ions

There are several studies examining prostate cancer and exposure to cadmium, iron, selenium, and zinc. Less data are available on the possible influence of these metal ions on prostate cancer outcome. This study measured levels of these ions in prostatectomy samples in order to examine possible associations between metal concentrations and disease outcome. We obtained formalin fixed paraffin embedded tissue blocks of prostatectomy samples of 40 patients with PSA recurrence, matched 1:1 (for year of surgery, race, age, Gleason grading, and pathology TNM classification) with tissue blocks from 40 patients without recurrence (n = 80). Case-control pairs were compared for the levels of metals in areas adjacent to tumors. Inductively coupled plasma-mass spectrometry (ICP-MS) was used for quantification of Cd, Fe, Zn, and Se. Patients with biochemical (PSA) recurrence of disease had 12% lower median iron (95 µg/g vs. 111 µg/g; P = 0.04) and 21% lower zinc (279 µg/g vs. 346 µg/g; P = 0.04) concentrations in the normal-appearing tissue immediately adjacent to cancer areas. Differences in cadmium (0.489 µg/g vs. 0.439 µg/g; 4% higher) and selenium (1.68 µg/g vs. 1.58 µg/g; 5% higher) levels were not statistically significant in recurrence cases, when compared to non-recurrences (P = 0.40 and 0.21, respectively). There is an association between low zinc and low iron prostate tissue levels and biochemical recurrence in prostate cancer. Whether these novel findings are a cause or effect of more aggressive tumors, or whether low zinc and iron prostatic levels raise implications for therapy, remains to be investigated.

Effect of arbuscular mycorrhizal fungi on plant biomass and the rhizosphere microbial community structure of mesquite grown in acidic lead/zinc mine tailings

Mine tailings in arid and semi-arid environments are barren of vegetation and subject to eolian dispersion and water erosion. Revegetation is a cost-effective strategy to reduce erosion processes and has wide public acceptance. A major cost of revegetation is the addition of amendments, such as compost, to allow plant establishment. In this paper we explore whether arbuscular mycorrhizal fungi (AMF) can help support plant growth in tailings at a reduced compost concentration. A greenhouse experiment was performed to determine the effects of three AMF inocula on biomass, shoot accumulation of heavy metals, and changes in the rhizosphere microbial community structure of the native plant Prosopis juliflora (mesquite). Plants were grown in an acidic lead/zinc mine tailings amended with 10% (w/w) compost amendment, which is slightly sub-optimal for plant growth in these tailings. After two months, AMF-inoculated plants showed increased dry biomass and root length ( p < 0.05) and effective AMF colonization compared to controls grown in uninoculated compost-amended tailings. Mesquite shoot tissue lead and zinc concentrations did not exceed domestic animal toxicity limits regardless of whether AMF inoculation was used. The rhizosphere microbial community structure was assessed using denaturing gradient gel electrophoresis (DGGE) profiles of the small subunit RNA gene for bacteria and fungi. Canonical correspondence analysis (CCA) of DGGE profiles showed that the rhizosphere fungal community structure at the end of the experiment was significantly different from the community structure in the tailings, compost, and AMF inocula prior to planting. Further, CCA showed that AMF inoculation significantly influenced the development of both the fungal and bacterial rhizosphere community structures after two months. The changes observed in the rhizosphere microbial community structure may be either a direct effect of the AMF inocula, caused by changes in plant physiology induced by AMF, or a combination of both mechanisms.

Response to commentary “Zinc is decreased in prostate cancer: an established relationship of prostate cancer!”

Response to commentary “Zinc is decreased in prostate cancer: an established relationship of prostate cancer!”

A Novel Imaging Approach for Early Detection of Prostate Cancer Based on Endogenous Zinc Sensing

The early detection of prostate cancer is a life-saving event in patients harboring potentially aggressive disease. With the development of malignancy, there is a dramatic reduction in the zinc content of prostate tissue associated with the inability of cancer cells to accumulate the ion. In the current study, we used endogenous zinc as an imaging biomarker for prostate cancer detection and progression monitoring. We employed a novel fluorescent sensor for mobile zinc (ZPP1) to detect and monitor the development of prostate cancer in a transgenic mouse model of prostate adenocarcinoma, using in vivo optical imaging correlated with biological fluid-based methods. We showed that the progression of prostate cancer could be monitored in vivo judging by the decreasing zinc content in the prostates of tumor-bearing mice in an age-dependent manner. In a novel quantitative assay, we determined the concentration of mobile zinc in both prostate cell lysates and mouse prostate extracts through simple titration of the ZPP1 sensor. Our findings fulfill the promise of zinc-based prostate cancer diagnostics with the prospect for immediate clinical translation.