Metallothionein Research Articles

Metallothionein Cup1 attenuates nitrosative stress in the yeast Saccharomyces cerevisiae.

Metallothionein (MT), which is a small metal-binding protein with cysteine-rich motifs, functions in the detoxification of heavy metals in a variety of organisms. Even though previous studies suggest that MT is involved in the tolerance mechanisms against nitrosative stress induced by toxic levels of nitric oxide (NO) in mammalian cells, the physiological functions of MT in relation to NO have not been fully understood. In this study, we analyzed the functions of MT in nitrosative stress tolerance in the yeast Saccharomyces cerevisiae. Our phenotypic analyses showed that deletion or overexpression of the MT-encoding gene, CUP1, led to higher sensitivity or tolerance to nitrosative stress in S. cerevisiae cells, respectively. We further examined whether the yeast MT Cup1 in the cell-free lysate scavenges NO. These results showed that the cell-free lysate containing a higher level of Cup1 degraded NO more efficiently. On the other hand, the transcription level of CUP1 was not affected by nitrosative stress treatment. Our findings suggest that the yeast MT Cup1 contributes to nitrosative stress tolerance, possibly as a constitutive rather than an inducible defense mechanism.

The Effects of Zinc Supplementation on Growth, Diarrhea, Antioxidant Capacity, and Immune Function in Holstein Dairy Calves.

The current study examined the effects of supplementary zinc proteinate (ZnPro) and zinc oxide (ZnO) on growth performance, diarrhea, antioxidant capacity, immune function, and mineral element concentrations of calves aged 1 to 28 days. A total of twenty-four newborn calves were divided randomly into 3 groups (n = 8; 2 males and 6 females per group), and each received: 0 mg/d Zn (CON), 627 mg/d ZnPro (80 mg/d Zn; ZnPro group), and 101 mg/d ZnO (80 mg/d Zn; ZnO group). The calves received the additive in their milk during the first 28 days of life. Compared with the CON group: ZnPro and ZnO improved average daily gain (ADG) and decreased the feed:gain ratio (FGR) between days 1 and 14 (p < 0.05), while the ADG increased and FGR decreased only in the ZnPro group between days 1 and 28 (p < 0.05). The incidence of diarrhea decreased (p < 0.05) in the ZnPro and ZnO groups between days 15 and 28 as well as days 1 and 28, but decreased (p < 0.05) only in the ZnPro group between days 1 and 14. The serum immunoglobulin G (IgG) concentration of the ZnPro and ZnO groups increased on days 14 and 28 (p < 0.05). ZnPro supplementation increased serum IgM concentration during the whole study, while ZnO enhanced serum IgM concentration only on day 14 (p < 0.05). In the ZnO group, the serum concentration of cytokines interleukin (IL)-10 increased on day 14, while that of IL-1β increased on day 28 (p < 0.05). In addition, ZnPro reduced the serum malondialdehyde (MDA) concentration on days 14 and 28 (p < 0.05). Both ZnPro and ZnO increased the serum concentrations of alkaline phosphatase (ALP) and metallothionein (MT) on day 14 (p < 0.05). With zinc supplementation, plasma Zn concentration increased (p < 0.05) on days 14 and 28 of age. We concluded that supplementary ZnPro and ZnO reduced incidences of diarrhea and promoted the immune function, but ZnPro improved the growth performance and antioxidant capacity of Holstein dairy calves to a greater extent.

Zinc Supplementation Reduces Testicular Cell Apoptosis in Mice and Improves Spermatogenic Dysfunction Caused by Marginal Zinc Deficiency.

Zinc (Zn) is an important trace element in the human body and plays an important role in growth, development, and male reproductive functions. Marginal zinc deficiency (MZD) is common in the human population and can cause spermatogenic dysfunction in males. Therefore, the aim of this study was to investigate methods to improve spermatogenic dysfunction caused by MZD and to further explore its mechanism of action. A total of 75 4-week-old male SPF ICR mice were randomly divided into five groups (control, MZD, MZD + ZnY2, MZD + ZnY4, and MZD + ZnY8, 15 mice per group). The dietary Zn content was 30mg/kg in the control group and 10mg/kg in the other groups. From low to high, the Zn supplementation doses administered to the three groups were 2, 4, and 8mg/kg·bw. After 35days, the zinc content, sperm quality, activity of spermatogenic enzymes, oxidative stress level, and apoptosis level of the testes in mice were determined. The results showed that MZD decreased the level of Zn in the serum, sperm quality, and activity of spermatogenic enzymes in mice. After Zn supplementation, the Zn level in the serum increased, sperm quality was significantly improved, and spermatogenic enzyme activity was restored. In addition, MZD reduced the content of antioxidants (copper-zinc superoxide dismutase (Cu-Zn SOD), metallothionein (MT), and glutathione (GSH) and promoted malondialdehyde (MDA) production. The apoptosis index of the testis also increased significantly in the MZD group. After Zn supplementation, the level of oxidative stress decreased, and the apoptosis index in the testis was reduced. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) showed that the expression of B-cell lymphoma-2 (Bcl-2) mRNA and Bcl-2/BCL2-associated X (Bax) in the control group decreased in testicular cells, and their expression was restored after Zn supplementation. The results of this study indicated that Zn supplementation can reduce the level of oxidative stress and increase the ability of testicular cells to resist apoptosis, thereby improving spermatogenic dysfunction caused by MZD in mice.

Mercury accumulation and biomarkers of exposure in two popular recreational fishes in Hawaiian waters

Mercury (Hg) exposure has not been examined in many recreational nearshore fish species that are commonly consumed around the Hawaiian Islands. Specific gene transcripts, such as metallothionein (MET) and thioredoxin reductase (TrxR), can be used to examine Hg exposure responses in aquatic organisms. This study measured total mercury (THg) in four species from two groups of Hawaiian nearshore fishes: giant trevally (Caranx ignobilis, n = 13), bluefin trevally (C. melampygus, n = 4), sharp jaw bonefish (Albula virgata, n = 2), and round jaw bonefish (A. glossodonta, n = 19). Total Hg accumulation and abundance profiles of MET and TrxR were evaluated for muscle, liver, and kidney tissues. Total Hg in round jaw bonefish and giant trevally tissues accumulated with length and calculated age. In round jaw bonefish tissues, mean THg was greater in kidney (1156 ng/g wet mass (wm)) than liver (339 ng/g wm) and muscle (330 ng/g wm). Giant trevally muscle (187 ng/g wm) and liver (277 ng/g wm) mean THg did not differ significantly. Fish species in this study were compared to commercial and local fish species with state and federal muscle tissue consumption advisories based on THg benchmarks developed by the U.S. Food and Drug Administration (FDA) and Environmental Protection Agency (EPA). Both bonefishes had mean muscle THg that exceeded benchmarks suggesting consumption advisories should be considered. MET transcript in round jaw bonefish kidney tissue and kidney THg exhibited a marginally significant positive correlation, while TrxR transcript in liver tissue negatively correlated with increasing liver THg. These results contribute to our understanding of Hg exposure associated health effects in fish.

Impacts of dietary zinc oxide nanoparticles on the growth and immunity of Nile tilapia could be ameliorated using Nigella sativa oil

BackgroundZinc nanoparticles are documented to be harmful to fish because their accumulation in fish bring about many irreversible changes in their health. Nigella sativa and its oil have been endorsed in aquaculture to improve fish health. MethodsTwo hundred seventy experimental fish (113 ± 5 g body weight) were divided into 6 groups G1–6; control fish fed a diet without any treatment (G1), 0.3% of NSO (G2), 0.5% of NSO (G3), ZnO NPs (40 mg/kg diet) (G4), 0.3% of NSO and ZnO NPs (40 mg/kg diet) (G5), 0.5% of NSO and ZnO NPs (40 mg/kg diet) (G6), the trial lasted for six weeks. ResultsGrowth performance was enhanced in fish received diets containing NSO, final weight (FW), weight gain (WG), daily weight gain (DWG), and relative growth rate (RGR) were significantly increased with lower food conversion ratios (FCR) compared to the control. The hepatic glutathione peroxidase (GPx), catalase (CAT), and metallothionein (MT) were increased in response to ZnO NPs stress and only 0.5% NSO supplementation could ameliorate such increment. The immune-related genes [interleukin1-beta (IL-1β), tumor necrosis factor-beta (TNF-β), transforming growth factor-beta 2 (TGF-β2) and C-type lysozyme] as well as growth-related gene [insulin-like growth factor 1 (IGF1)] in liver showed an upregulation in fish fed with NSO diets. Administration of ZnO NPs lowered the resistance of Oreochromis niloticus against bacterial infection with Aeromonas hydrophila and NSO could enhance the immunity in the highest tested concentration (0.5%) (G6). ConclusionsThe obtained results implied that NSO could enhance the oxidative and immune status of O. niloticus which could compensate ZnO NPs stress as well as experimental infection of a virulent strain of A. hydrophila. Our results revealed that NSO might increase fish growth and immunity only at a high dose (0.5%).

Zinc alleviates cadmium-induced reproductive toxicity via regulating ion homeostasis, metallothionein expression, and inhibiting mitochondria-mediated apoptosis in the freshwater crab Sinopotamon henanense

Cadmium (Cd) is a carcinogenic environmental pollutant that harms male reproductive systems by lowering sperm quality, impairing spermatogenesis, and causing apoptosis. Although zinc (Zn) has been reported to alleviate Cd toxicity, the underlying mechanisms have not been fully elucidated. The aim of this work was to investigate the mitigating effects of Zn on Cd-induced male reproductive toxicity in the freshwater crab Sinopotamon henanense. Cd exposure not only resulted in its accumulation but also in Zn deficiency, decreased sperm survival rate, poor sperm quality, altered ultrastructure, and increased apoptosis in the testis of the crabs. Morever, Cd exposure increased the expression and distribution of metallothionein (MT) in the testis. However, Zn supplementation effectively mitigated the aforementioned effects of Cd, as demonstrated by preventing Cd accumulation, increasing Zn bioavailability, alleviating apoptosis, increasing mitochondrial membrane potential, decreasing reactive oxygen species (ROS) levels, and restoring MT distribution. Moreover, Zn also significantly reduced the expression of apoptosis-related (p53, Bax, CytC, Apaf-1, Caspase-9, Caspase-3), metal transporter-related ZnT1, metal-responsive transcription factor 1 (MTF1), and the gene and protein expression of MT, while increasing the expression of ZIP1 and Bcl-2 in the testis of Cd-treated crabs. In conclusion, Zn alleviates Cd-induced reproductive toxicity via regulating ion homeostasis, MT expression, and inhibiting mitochondria-mediated apoptosis in the testis of S. henanense. The information obtained in this study may serve as the foundation for further investigation into the development of mitigation strategies for adverse ecological and human health outcomes associated with Cd contamination or poisoning.

398-P: Renal Proximal Tubular Metallothionein 3 Contributes to Diabetic Kidney Lesion

Metallothionein (MT) is a cysteine-rich protein with an antioxidant. MT3, one isoform of the four MTs, is upregulated in the renal proximal tubular cells in type 2 diabetic subjects. To investigate the role of human MT3, we used the mouse sglt2 promoter for targeting human MT3 gene to renal proximal tubular cells in transgenic mice (MT3TG). MT3TG showed nodular glomerulosclerosis without hyperglycemia. Electron microscopy presented thickened glomerular basement membranes, numerous endoplasmic reticulum in proximal tubules and cytoplasmic swelling of the endothelium of peritubular capillaries accompanied with abnormal capillary formation around the glomerulus, suggesting proximal tubular MT3 induces retrogradely glomerular hypertension. Affymetrix Human Gene 1.0 ST arrays identified 43 upregulated and 81 downregulated genes between control and MT3-knockdown human renal proximal tubular epithelial cells (HRPTECs, Lonza) under hypoxia, an early event in diabetic kidney. Among them, ceruloplasmin (CP) and cytochrome b reductase 1 (CYBRD), the crucial players in the cooper and iron metabolism, were downregulated. In fact, MT3TG presented cytoplasmic co-expression of MT3, CP and CYBRD1 in renal proximal tubules. Hypoxia induced a remarkable increase in MT3 in HRPTECs, and the HIF-1alpha siRNAs abolished that. Despite of no antioxidant response element in the human MT3 promoter, Nrf2 siRNA significantly decreased hypoxia-induced MT3 expression. Moreover, MT3 and Nrf2 siRNAs inhibited hypoxia-induced CP and CYBRD1, but not HIF-1 alpha siRNA. Together with the inhibitory effects of mitochondrial inhibitors, NOX4 inhibitors and antioxidant NAC on hypoxia-induced MT3 expression, hypoxia-induced oxidative stress might be involved in the inductions of CP and CYBRD1. Of note, empagliflozin decreased hypoxia-induced MT3, CP and CYBRD1. Our study suggests that MT3 might contributes to diabetic kidney lesion via CP and CYBRD1against hypoxia-induced oxidative stress. Disclosure Y.Takiyama: None. T.Takiyama: None. R.Bessho: None. H.Kitsunai: None. Y.Takiyama: Research Support; Boehringer Ingelheim Japan, Inc., Taisho Pharmaceutical Holdings Co., Ltd., Ono Pharmaceutical Co., Ltd., Abbott Japan Co., Ltd., Roche Diabetes Care, MSD Life Science Foundation, Japan Society for the Promotion of Science, Teijin Pharma Limited, Kyowa Kirin Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd., Eli Lilly Japan K.K.

Effects and mechanism of glycine on rat cardiomyocytes pretreated with serum from burned rats

Effects and mechanism of glycine on rat cardiomyocytes pretreated with serum from burned rats

Heavy metal accumulation, biochemical and transcriptomic biomarkers in earthworms Eisenia andrei exposed to industrially contaminated soils from south-eastern Tunisia (Gabes Governorate)

Heavy metal pollution is causing harmful consequences on soil fertility, and earthworms are frequently employed as test organisms to evaluate the ecotoxicity of polluted soils. In this study, Eisenia andrei was exposed for 7 and 14 days to polymetallic contaminated soils collected from an industrial zone in the south-eastern Tunisia. Earthworm growth, heavy metal accumulation, genotoxicity, cytotoxicity, biochemical and transcriptional responses were determined. Results revealed a higher accumulation of heavy metals in earthworms after 14 than 7 days of soil exposure, a reduction in lysosomal membrane stability (LMS), besides an increase in micronuclei frequency (MN). Moreover, earthworm oxidative status was affected in terms of increases in malondialdehyde (MDA) and metallothionein (MTs) content, and enhancement of catalase (CAT) and glutathione-S-transferase (GST) activities. An inhibition of acetylcholinesterase (AChE) activity was also observed in treated earthworms, whereas transcriptional data demonstrated an up-regulation of cat, gst, mt, p21 and topoisomerase genes. Overall, these findings support the use of earthworms as suitable bioindicator species for pollution monitoring and assessment, advance our understanding of the interaction between heavy metals and earthworms, and provide valuable information about the harmful impact of biota exposure to naturally contaminated soils.

New insight into the toxic effects of lithium in the ragworm Perinereis cultrifera as revealed by lipidomic biomarkers, redox status, and histopathological features.

Lithium (Li) is a toxic monovalent alkaline metal used in household items common to industrial applications. The present work was aimed at investigating the potential toxic effects of LiCl on the redox status, fatty acid composition, and histological aspects of the marine ragworm Perinereis cultrifera. Sea worms were exposed to LiCl graded doses (20, 40, and 80mg/L) for 48h. Compared with the control group, the saturated fatty acids (SFA) decreased while monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) increased upon exposure to LiCl. The increase in PUFA n-3 and PUFA n-6 was concomitant to an increase in docosahexaenoic (DHA: C22:6n-3), eicosapentaenoic (EPA: C20:5n-3), and docosapentaenoic acid (C22:5n-6) fatty acids. Results showed that LiCl-treated specimens accumulate lithium with increasing exposure gradient. Indeed, the exposure to LiCl doses promoted oxidative stress with an increase of the ferric reducing antioxidant power (FRAP), malondialdehyde (MDA), hydrogen peroxide (H2O2), advanced oxidation protein product (AOPP), and protein carbonyl (PCO) as well as the enzymatic and non-enzymatic antioxidants (non-protein thiols (NPSH), catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione S-transferase (GST), and metallothionein (MT)) levels in all treated groups. Our biochemical findings have been affirmed by the histopathological observations showing hyperplasia and loss of the intestine structure in treated specimens. Overall, our findings give new insights on the toxic effect of LiCl on the redox status of P. cultrifera body tissue and highlighted the usefulness of the FA composition as an early sensitive bioindicators to better understand LiCl mechanism of toxicity in marine polychaetes.

Effects of cadmium and zinc on gene expression of novel molecular biomarkers in the mangrove oyster Crassostrea gasar

Metal contamination impacts various aquatic species, and mollusk bivalves are appropriate sentinel organisms in coastal pollution assessment. Metal exposure can disrupt homeostasis, alter gene expression, and harm cellular processes. However, organisms have evolved mechanisms to regulate metal ions and counteract their toxicity. This study examined the effect of acute cadmium (Cd) and zinc (Zn) on metal-related gene expression in gills of Crassostrea gasar following 24 and 48 h of laboratory exposure. We focused on Zn transport, metallothionein (MT), glutathione (GSH) biosynthesis, and calcium (Ca) transporter genes to understand the underlying Cd and Zn-accumulating mechanisms that prevent metal toxicity. Our findings revealed increased Cd and Zn levels in oyster gills, with significantly higher accumulation after 48 h. C. gasar accumulated high Cd concentrations even in scarce conditions and increased Zn levels, suggesting a strategy to cope with toxicity. While no significant gene expression differences were observed after 24 h, the increased metal accumulation after 48 h led to upregulation of CHAC1, GCLC, ZnT2, and MT-like genes in oysters exposed to Cd, and increased ZnT2-like expression following exposure to higher Cd/Zn mixtures. We found evidence of oysters may mobilize metal-related genes to mitigate Cd-induced toxicity by both chelating metals and/or reducing their intracellular concentrations. The observed genes upregulation also indicates their sensitivity to changes in metal bioavailability. Overall, this study offers insights into oyster mechanisms for coping with metal toxicity and suggests ZnT2, MT, CHAC1, and GCLC-like as molecular biomarkers for monitoring aquatic metal pollution using C. gasar as sentinel species.

Identification of metallothionein protein in Anodonta woodiana as a biomarker of mercury (Hg) contamination

Abstract. Rahayu SYS, Fadila A, Fahmi MR. 2023. Identification of metallothionein protein in Anodonta woodiana as a biomarker of mercury (Hg) contamination. Nusantara Bioscience 15: 90-94. Heavy metal contamination can affect the survival of aquatic biota and will accumulate in the bodiesorganisms. Moreover, contamination identification at the molecular level can be analyzed using biomarker analysis. Biomarkers are responses measured individually, ranging from enzymes and xenobiotic measurements to organ and overall conditions. Biomarker analysis can be done by checking the metallothionein protein, this expression can be induced by Reactive Oxygen Species (ROS). Metallothionein (MT) has a thiol group with nucleophilic properties. As a result, this group can make Metallothionein able to find metals and free radicals. Therefore, prevention that can be done to reduce contamination at a higher trophic level requires monitoring the molecular level by observing the metallothionein protein. For example, Anodonta woodiana (Rea, 1834) or kijing taiwan induced by HgCl2 aims to characterize their absorption ability in the environment through metallothionein protein. That was conducted by the SDS-PAGE (Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) method. SDS-PAGE electrophoresis results showed that the size of the metallothionein protein was 7 kDa, 15 kDa, and &gt;30 kDa. Size &gt;30 kDa is a group of proteins related to stress control or Heat shock protein (Hsp). The presence of Hsp is due to the body increasing stress protein synthesis and metallothionein to reduce normal protein synthesis. Based on the results obtained, this study revealed that A. woodiana could absorb HgCl2, as evidenced by the metallothionein protein characterization results.

Genome-wide analysis of the metallothionein gene family in cassava reveals its role in response to physiological stress through the regulation of reactive oxygen species

BackgroundCassava (Manihot esculenta Crantz) is widely planted in tropical and several subtropical regions in which drought, high temperatures, and other abiotic stresses occur. Metallothionein (MT) is a group of conjugated proteins with small molecular weight and rich in cysteine. These proteins play a substantial role in response to physiological stress through the regulation of reactive oxygen species (ROS). However, the biological functions of MT genes in cassava are unknown.ResultsA total of 10 MeMT genes were identified in the cassava genome. The MeMTs were divided into 3 groups (Types 2–4) based on the contents and distribution of Cys residues. The MeMTs exhibited tissue-specific expression and located on 7 chromosomes. The MeMT promoters contain some hormones regulatory and stresses responsiveness elements. MeMTs were upregulated under hydrogen peroxide (H2O2) treatment and in respond to post-harvest physiological deterioration (PPD). The results were consistent with defense-responsive cis-acting elements in the MeMT promoters. Further, four of MeMTs were selected and silenced by using the virus-induced gene silencing (VIGS) method to evaluate their functional characterization. The results of gene-silenced cassava suggest that MeMTs are involved in oxidative stress resistance, as ROS scavengers.ConclusionWe identified the 10 MeMT genes, and explore their evolutionary relationship, conserved motif, and tissue-specific expression. The expression profiles of MeMTs under three kinds of abiotic stresses (wounding, low-temperature, and H2O2) and during PPD were analyzed. The tissue-specific expression and the response to abiotic stresses revealed the role of MT in plant growth and development. Furthermore, silenced expression of MeMTs in cassava leaves decreased its tolerance to ROS, consistent with its predicted role as ROS scavengers. In summary, our results suggest an important role of MeMTs in response to physiological stress as well as species adaptation via the regulation of ROS homeostasis.

Direct Synthesis of EM-Visible Gold Nanoparticles in Cells for Protein Localization Analysis with Well-preserved Ultrastructure.

Analyzing the precise localization of protein molecules in cells with ultrastructural resolution is of great significance for the study of various physiological or pathological processes in all living organisms. Therefore, the development of clonable tags that can be used as electron microscopy probes is of great value, just as fluorescent proteins have played a crucial role in the field of optical imaging. The autonucleation suppression mechanism (ANSM) was recently uncovered, which allows for the specific synthesis of gold nanoparticles (AuNPs) on cysteine-rich tags, such as metallothionein (MT) and antifreeze protein (AFP). Based on the ANSM, an electron microscopy labeling technology was developed, which enables the specific detection of tagged proteins in prokaryotic and eukaryotic cells with an unprecedented labeling efficiency. This study illustrates a protocol for the detection of MTn (an engineered MT variant lacking aldehyde-reactive residues) fusion proteins in mammalian cells with well-preserved ultrastructure. In this protocol, high-pressure freezing and freeze-substitution fixation were performed using non-aldehyde fixatives (such as tannic acid, uranyl acetate) to preserve near-native ultrastructure and avoid damage to the tag activity caused by aldehyde crosslinking. A simple one-step rehydration was used prior to the ANSM-based AuNP synthesis. The results showed that the tagged proteins targeted various organelles, including the membranes and the lumen of the endoplasmic reticulum (ER), and mitochondrial matrices were detected with high efficiency and specificity. This research provides biologists with a robust protocol to address an enormous range of biological questions at the single-molecule level in cellular ultrastructural contexts.

Effect of Two Particle Sizes of Nano Zinc Oxide on Growth Performance, Immune Function, Digestive Tract Morphology, and Intestinal Microbiota Composition in Broilers.

The effects of dietary supplementation with two particle sizes of nano zinc oxide (ZnO) on growth performance, immune function, intestinal morphology, and the gut microbiome were determined in a 42-day broiler chicken feeding experiment. A total of 75 one-day-old Arbor Acres broilers were randomized and divided into three groups with five replicates of five chicks each, including the conventional ZnO group (NC), the nano-ZnO group with an average particle size of 82 nm (ZNPL), and the nano-ZnO group with an average particle size of 21 nm (ZNPS). Each group was supplemented with 40 mg/kg of ZnO or nano-ZnO. Our results revealed that birds in the ZNPS group had a higher average daily gain and a lower feed-to-gain ratio than those in the NC group. ZNPS significantly increased the thymus index and spleen index, as well as the levels of serum metallothionein (MT), superoxide dismutase (SOD), and lysozyme (LZM). The ZNPS treatments reduced interleukin (IL)-1β and tumor necrosis factor-alpha (TNF-α) levels and increased IL-2 and interferon (IFN)-γ levels compared to that in the NC group. Additionally, compared with the birds in the NC group, those in the nano-ZnO group had a higher villus height to crypt depth ratio of the duodenum, jejunum, and ileum. Bacteroides increased in the ZNPS group at the genus level. Further, unidentified_Lachnospiraceae, Blautia, Lachnoclostridium, unidentified_Erysipelotrichaceae, and Intestinimonas were significantly increased in the ZNPL group. In conclusion, nano-ZnO improved the growth performance, promoted the development of immune organs, increased nonspecific immunity, improved the villus height to crypt depth ratio of the small intestine, and enriched the abundance of beneficial bacteria. Notably, the smaller particle size (21 nm) of nano-ZnO exhibited a more potent effect.

Ferroptosis is involved in polymyxin B-induced acute kidney injury via activation of p53

Polymyxin B (PMB) is one of the most effective drugs for the treatment of multi-resistant and pan-resistant gram-negative infections. However, it can induce acute kidney injury (AKI), the mechanism of which has not yet been fully elucidated. In this study, RNA sequencing and in vitro and in vivo experiments demonstrated that PMB induced AKI by promoting ferroptosis. Moreover, the metallothionein-1 (MT-1) level was significantly increased in the AKI group and clinical cases revealed that iron and MT-1 levels in urine were significantly higher in patients with AKI than in those without AKI. To explore the mechanism of PMB induced ferroptosis, we silenced p53 in human kidney-2 (HK2) cells according to RNA sequencing, which showed that p53 was obviously enhanced in the PMB treated group. While PMB significantly enhanced Fe2+, lipid peroxidation, malondialdehyde (MDA), transferrin receptor protein 1 (TFR1), and arachidonate 12-lpoxygenase (ALOX12), decreased the survival rate, solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and glutathione (GSH), downregulation of p53 reversed these effects, suggesting PMB induced ferroptosis by activating p53. Studies have shown p53 can promote ferroptosis by regulating the downstream factors SLC7A11 or TFR1. Further, we verified that silencing TFR1 expression as well as overexpression of SLC7A11 inhibited ferroptosis and significantly increased the survival rate of HK2 cells. Overall, PMB induces ferroptosis in renal tubular cells by activating p53 to reduce SLC7A11 expression and elevate TFR1, leading to AKI; MT-1 and iron levels in urine were significantly increased when PMB induced ferroptosis.

Heavy metal–induced genotoxic, physiological, and biochemical responses in Schizothorax esocinus (Heckel 1838) inhabiting the Dal Lake, India, and phytoremediation by indwelling plants

Heavy metals have animmense impact on aquatic ecosystems, and their toxic effects are transferred to the inhabiting organisms. Experiments were conducted to investigate the health of snow trout Schizothorax esocinus inhabiting Dal Lake. Heavy metals (Cd > Ni > Cu > Cr) were found to accumulate in the major immune organs of the fish (head kidney, liver, spleen, thymus) which led to change in the overall physiology. The head kidney, liver, and spleen of a fish contain high amount of these metals. The least accumulation of these metals was found in the blood, whereas Cd and Ni were completely absent in the integument. Hepatic marker enzymes (aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP)) were normal, while the renal marker enzyme creatine kinase showed marked difference in its value. The cortisol level was normal, while immunoglobulin M showed elevated level representing active immunity. At a cellular level, the histopathology of immune organs showed marked damage. Metallothionein (MT) and glutathione peroxidase (GPX) genes showed variable expression pattern in the immune organs with the head kidney showing the highest expression of both the genes, and blood showed the least. We observed that the aquatic plants (Nelumbo nucifera and Trapa natans) inhabiting the lake played an important role in phytoremediation. An integrated approach involving biochemical, hematological, genotoxic, and histopathological studies can provide a valuable information to understand fish adaptive patterns and monitor water quality.

Expression pattern and prognostic implication of zinc homeostasis-related genes in acute myeloid leukemia.

Zinc homeostasis is regulated by the SLC39A/ZIP, SLC30A/ZnT, and metallothionein (MT) protein families. The association of zinc homeostasis with acute myeloid leukemia (AML) is unclear. We previously demonstrated that zinc depletion by TPEN triggers apoptosis in NB4 AML cells with the degradation of PML-RARα oncoprotein, suggesting that zinc homeostasis may be associated with AML. The primary aim of this study was to explore the expression pattern and prognostic roles of zinc homeostasis-related genes in AML. Bioinformatics analyses were performed using integrated datasets from the TCGA and GTEx projects. The GEPIA tool was used to analyze the differential expression of zinc homeostasis-related genes. Correlations between zinc homeostasis-related genes were assessed with Spearman's correlation coefficient. OncoLnc was used to evaluate the prognostic roles of zinc homeostasis-related genes with Kaplan-Meier and Cox regression models. In both NB4 and U937 cells, the transcriptional regulation of zinc homeostasis-related genes by zinc depletion was detected through qPCR. We found that multiple ZIPs, ZnTs, and MTs were differentially expressed and correlated in AML tumors. In AML patients, higher expression of ZIP4 and lower expression of ZnT5 and ZnT7 predicted poorer survival. We further found that zinc depletion by TPEN upregulated ZIP7, ZIP9, ZIP10, ZIP13, and ZnT7 and downregulated ZIP14, ZnT1, ZnT6, and most of the positively expressed MTs in both NB4 and U937 AML cells. Our findings suggest high expression of ZIP4 and low expression of ZnT5 and ZnT7 as potential risk factors for the prognosis of AML. Zinc homeostasis may be a potential therapeutic target for AML, deserving further exploration.

Primary and Immortalized Cultures of Human Proximal Tubule Cells Possess Both Progenitor and Non-Progenitor Cells That Can Impact Experimental Results.

Studies have reported the presence of renal proximal tubule specific progenitor cells which co-express PROM1 and CD24 markers on the cell surface. The RPTEC/TERT cell line is a telomerase-immortalized proximal tubule cell line that expresses two populations of cells, one co-expressing PROM1 and CD24 and another expressing only CD24, identical to primary cultures of human proximal tubule cells (HPT). The RPTEC/TERT cell line was used by the authors to generate two new cell lines, HRTPT co-expressing PROM1 and CD24 and HREC24T expressing only CD24. The HRTPT cell line has been shown to express properties expected of renal progenitor cells while HREC24T expresses none of these properties. The HPT cells were used in a previous study to determine the effects of elevated glucose concentrations on global gene expression. This study showed the alteration of expression of lysosomal and mTOR associated genes. In the present study, this gene set was used to determine if pure populations of cells expressing both PROM1 and CD24 had different patterns of expression than those expressing only CD24 when exposed to elevated glucose concentrations. In addition, experiments were performed to determine whether cross-talk might occur between the two cell lines based on their expression of PROM1 and CD24. It was shown that the expression of the mTOR and lysosomal genes was altered in expression between the HRTPT and HREC24T cell lines based on their PROM1 and CD24 expression. Using metallothionein (MT) expression as a marker demonstrated that both cell lines produced condition media that could alter the expression of the MT genes. It was also determined that PROM1 and CD24 co-expression was limited in renal cell carcinoma (RCC) cell lines.

An Assessment of MT1A (rs11076161), MT2A (rs28366003) and MT1L (rs10636) Gene Polymorphisms and MT2 Concentration in Women with Endometrial Pathologies

Several studies have indicated a relationship between metallothionein (MT) polymorphisms and the development of different pathologies, including neoplastic diseases. However, no studies thus far have been conducted on the influence of MT polymorphisms and the development of endometrial lesions, including endometrial cancer. This study included 140 patients with normal endometrial tissue, endometrial polyps, uterine myomas and endometrial cancer. The tissue MT2 concentration was determined using the ELISA method. MT1A, MT2A and MT1L polymorphisms were analyzed using TaqMan real-time PCR genotyping assays. We found no statistical difference between the tissue MT2 concentration in patients with EC vs. benign endometrium (p = 0.579). However, tissue MT2 concentration was significantly different between uterine fibromas and normal endometrial tissue samples (p = 0.019). Menopause status did not influence the tissue MT2 concentration (p = 0.282). There were no significant associations between the prevalence of MT1A, MT2A and MT1L polymorphisms and MT2 concentration. The age, menopausal status, and diabetes status of patients were identified as EC risk factors.