Zinc Transporter ZIP12 Maintains Zinc Homeostasis and Protects Spermatogonia From Oxidative Stress During Spermatogenesis

Abstract Background: Overwhelming evidences now suggest oxidative stress is a major cause of sperm dysfunction and male infertility. Zinc is an important non-enzyme antioxidant with a wide range of biological functions and plays a significant role in preserving male fertility. Notably, zinc trafficking through the cellular and intracellular membrane is endorsed by precise families of zinc transporters, i.e. SLC39s/ZIPs and SLC30s/ZnTs. However, the expression and function of zinc transporters in the male germ cells were rarely reported. The aim of this study is to determine the crucial zinc transporter responsible for the maintenance of spermatogenesis.Methods: In the present study, we investigated the expression of all fourteen ZIP members in mouse testis and further analyzed the characteristic of ZIP12 expression in testis and spermatozoa by qRT-PCR, immunoblot and immunohistochemistry analyses. To explore the antioxidant role of ZIP12 in spermatogenesis, an obese mouse model fed with high-fat-diet was employed to confirm the correlation between ZIP12 expression level and sperm quality. Furthermore, ZIP12 expression in response to oxidative stress in a spermatogonia cell line, C18-4 cells, was determined and its function involved in regulating cell viability and apoptosis was investigated by RNAi experiment. Results: We initially found that ZIP12 expression in mouse testis was significantly high compared to other members of ZIPs and its mRNA and protein were intensively expressed in testis rather than the other tissues. Importantly, ZIP12 was intensively abundant in spermatogonia and spermatozoa, both in mice and humans. Moreover, ZIP12 expression in testis significantly decreased in obese mice, which associated with reduced sperm zinc content, excessive sperm ROS, poor sperm quality and male subfertility. Similarly, its expression in C18-4 cells significantly declined in response to oxidative stress. Additionally, reduced ZIP12 expression by RNAi associated with a decline in zinc level subsequently caused low cell viability and high cell apoptosis in C18-4 cells. Conclusions: The zinc transporter ZIP12 is intensively expressed in testis, especially in spermatogonia and spermatozoa. ZIP12 may play a key role in maintaining intracellular zinc level in spermatogonia and spermatozoa, by which it resists oxidative stress during spermatogenesis and therefore preserves male fertility.

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The role of zinc transporter proteins as predictive and prognostic biomarkers of hepatocellular cancer

PeerJ ◽

10.7717/peerj.12314 ◽

2021 ◽

Vol 9 ◽

pp. e12314

Author(s):

Ceylan V. Bitirim

Keyword(s):

Tumor Progression ◽

Zinc Deficiency ◽

Zinc Level ◽

Zinc Transporter ◽

Tumor Formation ◽

Zinc Homeostasis ◽

Zinc Transporters ◽

Transporter Proteins ◽

Grade Ii ◽

Cellular Zinc

Identification of the key processes involved in the tumor progression, malignancy and the molecular factors which are responsible for the transition of the cirrhotic cells to the tumor cells, contribute to the detection of biomarkers for diagnosis of hepatocellular carcinoma (HCC) at an early stage. According to clinical data, HCC is mostly characterized by a significant decrease in zinc levels. It is strongly implied that zinc deficiency is the major event required in the early stages of tumor formation and development of malignancy. Due to this reason, the definition of the molecular players which have a role in zinc homeostasis and cellular zinc level could give us a clue about the transition state of the cirrhosis to hepatic tumor formation. Despite the well-known implications of zinc in the development of HCCthe correlation of the expression of zinc transporter proteins with tumor progression and malignancy remain largely unknown. In the present study, we evaluated in detail the relationship of zinc deficiency on the prognosis of early HCC patients. In this study, we aimed to test the potential zinc transporters which contribute tothe transformation of cirrhosis to HCCand the progression of HCC. Among the 24 zinc transporter proteins, the proteins to be examined were chosen by using Gene Expression Profiling Interactive Analysis (GEPIA) webpage and RNA-seq analysis using TCGA database. ZIP14 and ZIP5 transporters were found as common differentially expressed genes from both bioinformatic analyses. ZnT1, ZnT7 and ZIP7 transporters have been associated with tumor progression. Relative abundance of ZnT1, ZIP5 and ZIP14 protein level was determined by immunohistochemistry (IHC) in surgically resected liver specimens from 16 HCC patients at different stages. IHC staining intensity was analyzed by using ImageJ software and scored with the histological scoring (H-score) method. The staining of ZnT1 was significantly higher in Grade III comparing to Grade II and Grade I. On the contrary, ZIP14 staining decreased almost 10-foldcomparing to Grade Iand Grade II. ZIP5 staining was detected almost 2-fold higher in cirrhosis than HCC. But ZnT1 staining was observed almost 3-fold lower in cirrhosis comparing to HCC. Intracellular free zinc level was measured by flow cytometry in Hep40 and Snu398 cells using FluoZin-3 dye. The intracellular free zinc level was almost 9-fold decreased in poor differentiated Snu398 HCC cells comparing to well differentiated Hep40 HCC cells.This report establishes for the first time the correlation between the expression pattern of ZIP14, ZnT1 and ZIP5 and significant zinc deficiency which occurs concurrently with the advancing of malignancy. Our results provide new molecular insight into ZnT1, ZIP14 and ZIP5 mediated regulation of cellular zinc homeostasis and indicate that zinc transporters might be important factors and events in HCC malignancy, which can lead to the development of early biomarkers.

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Antioxidants and Polyphenols: Concentrations and Relation to Male Infertility and Treatment Success

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/9140925 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 5

Author(s):

Tali Silberstein ◽

Iris Har-Vardi ◽

Avi Harlev ◽

Michael Friger ◽

Batel Hamou ◽

...

Keyword(s):

Oxidative Stress ◽

Male Fertility ◽

Sperm Quality ◽

Treatment Success ◽

Sperm Concentration ◽

Infertility Treatment ◽

Fertility Treatment ◽

Fertilization Rates ◽

Total Antioxidant ◽

Antioxidant Concentration

Oxidative stress is induced by reactive oxygen substances (ROS) that are known to affect male fertility. The aims of this study were to prospectively investigate and characterize total antioxidant and specifically polyphenols concentrations and their relations to sperm quality and fertility treatment success. During their infertility treatment, sixty-seven males were prospectively recruited to this study. After separation of the sperm from the semen sample, the semen fluid samples antioxidants and polyphenols concentrations were determined. Antioxidant concentration was significantly associated with sperm concentration and total motile count. Antioxidants concentration in the group of male with sperm concentration ≥ 15 × 106was significantly higher than in the group of male with antioxidants concentration < 15 × 106(830.3 ± 350 μM and 268.3 ± 220 μM, resp.,p<0.001). Polyphenols concentration did not differ between the groups of sperm concentration above and below 15 × 106(178.7 ± 121 μM and 161.7 ± 61 μM, resp.,p-NS). No difference was found between fertilization rates and antioxidants or polyphenols concentrations. This is the first study that reports on polyphenols concentration within semen fluid. More studies are needed in order to investigate polyphenols role in male fertility.

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Impact of Environmental and Lifestyle Use of Chromium on Male Fertility: Focus on Antioxidant Activity and Oxidative Stress

Antioxidants ◽

10.3390/antiox10091365 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1365 ◽

Cited By ~ 1

Author(s):

Sara C. Pereira ◽

Pedro F. Oliveira ◽

Sónia Rodrigues Oliveira ◽

Maria de Lourdes Pereira ◽

Marco G. Alves

Keyword(s):

Oxidative Stress ◽

Reproductive Health ◽

Male Fertility ◽

Sperm Quality ◽

Antioxidant Properties ◽

Chromium Picolinate ◽

Chromium Vi ◽

Valence States ◽

Chromium Compounds ◽

Male Reproductive Health

Male reproductive tissues are strongly susceptible to several environmental and lifestyle stressors. In general, male reproductive health is highly sensitive to oxidative stress, which results in reversible and/or irreversible changes in testosterone-producing cells, spermatogenesis, and sperm quality. Chromium compounds are widely used in the +3 and +6 valence states, as food supplements, and in the industrial field, respectively. Chromium (III) compounds, i.e., Cr(III)-tris-picolinate, [Cr(pic)3], known as chromium picolinate, are used as nutritional supplements for the control of diabetes, body weight, and muscular growth. However, previous studies showed that animal models exposed to chromium picolinate experienced degenerative changes in spermatogenesis. Contradictory results are documented in the literature and deserve discussion. Furthermore, the long-term effects of chromium picolinate on the antioxidant system of treated subjects have not been properly studied. Comprehensive studies on the role of this compound will help to establish the safe and useful use of chromium supplementation. On the other hand, chromium (VI) compounds are widely used in several industries, despite being well-known environmental pollutants (i.e., welding fumes). Chromium (VI) is known for its deleterious effects on male reproductive health as toxic, carcinogenic, and mutagenic. Previous studies have demonstrated severe lesions to mouse spermatogenesis after exposure to chromium (VI). However, workers worldwide are still exposed to hexavalent chromium, particularly in electronics and military industries. Data from the literature pinpoints mechanisms of oxidative stress induced by chromium compounds in somatic and germ cells that lead to apoptosis, thus underlining the impairment of fertility potential. In this review, we analyze the benefits and risks of chromium compounds on male fertility, as well as the mechanisms underlying (in)fertility outcomes. Although supplements with antioxidant properties may maximize male fertility, adverse effects need to be investigated and discussed.

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Function, Structure, and Transport Aspects of ZIP and ZnT Zinc Transporters in Immune Cells

Journal of Immunology Research ◽

10.1155/2018/9365747 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 13

Author(s):

Bum-Ho Bin ◽

Juyeon Seo ◽

Sung Tae Kim

Keyword(s):

Immune Cells ◽

Drug Targets ◽

Therapeutic Potential ◽

Family Members ◽

Zinc Transporter ◽

Zinc Homeostasis ◽

Zinc Transporters ◽

Function Structure ◽

Rich Domain ◽

Zip Family

Zinc is an important trace metal in immune systems, and zinc transporters are involved in many immune responses. Recent advances have revealed the structural and biochemical bases for zinc transport across the cell membrane, with clinical implications for the regulation of zinc homeostasis in immune cells like dendritic cells, T cells, B cells, and mast cells. In this review, we discuss the function, structure, and transport aspects of two major mammalian zinc transporter types, importers and exporters. First, Zrt-/Irt-like proteins (ZIPs) mediate the zinc influx from the extracellular or luminal side into the cytoplasm. There are 14 ZIP family members in humans. They form a homo- or heterodimer with 8 transmembrane domains and extra-/intracellular domains of various lengths. Several ZIP members show specific extracellular domains composed of two subdomains, a helix-rich domain and proline-alanine-leucine (PAL) motif-containing domain. Second, ZnT (zinc transporter) was initially identified in early studies of zinc biology; it mediates zinc efflux as a counterpart of ZIPs in zinc homeostasis. Ten family members have been identified. They show a unique architecture characterized by a Y-shaped conformation and a large cytoplasmic domain. A precise, comprehensive understanding of the structures and transport mechanisms of ZIP and ZnT in combination with mice experiments would provide promising drug targets as well as a basis for identifying other transporters with therapeutic potential.

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Effect of N-acetyl cysteine, Neopterin and Dexamethasone on the Viability of Titanium dioxide Nanoparticles Exposed Cell Lines

Pteridines ◽

10.1515/pteridines.2012.23.1.111 ◽

2012 ◽

Vol 23 (1) ◽

pp. 111-122 ◽

Cited By ~ 2

Author(s):

Ayse Basak Engin ◽

Evren Doruk Engin ◽

Bensu Karahalil

Keyword(s):

Oxidative Stress ◽

Titanium Dioxide ◽

Cell Viability ◽

Cell Survival ◽

Cell Lines ◽

U937 Cell ◽

Cytotoxic Effects ◽

Wide Range ◽

Acetyl Cysteine ◽

Nano Size

Abstract Titanium is extensively used for a wide range of implanted medical devices due to its advantageous combination of physico-chemical and biological properties. Nano-size titanium dioxide (TiO2) is also used in a variety of consumer products. Such widespread use and its potential entry through various routes of the body suggest that TiO2 could pose an exposure risk to humans. Nano-size particles (NP) enter systemic circulation, accumulate and damage tissues that are especially sensitive to oxidative stress. We hypothesized that TiO2 NPs can exert diverse cytotoxic effects on various human cell type especially neural cell lines. In order to test our hypothesis, putative cytotoxic effects of oxidative stress due to TiO2 NPs exposure on IM9, U937 and SHSY5Y (human neuroblastoma cells) were investigated in N-acetyl cysteine (NAC), neopterin and dexamethasone pre-treated cell cultures. IM9, U937 and SHSY5Y cells were exposed to ten different concentrations of 25 and 10 nm diameter TiO2 NPs in three different time periods before and after treatment with NAC, neopterin and dexamethasone. To determine toxicity levels of NPs, cell viability was estimated by MTT test. Concentration of cells was assessed by counting trypan blue stained cells with a heamo-cytometer. Toxicity of 25nm TiO2 particles was significantly increased (p<0.05) by adding fetal bovine serum (FBS) in SHYS5Y and U937 cell lines culture medium. Concentrationdependent toxicity of 10 nm TiO2 NP was weakly increased by adding FBS to SHYS5Y, IM9 and U937 cell culture media. NAC pre-treatment provided significant protection for only SHYS5Y cell exposed to 25 nm and 10 nm of TiO2 NPs after a 24-hour incubation period. Neopterin pre-treated SHYS5Y cells displayed significant increases in viability after 24-hour exposure to 10 nm and 25 nm TiO2 NPs. While exposure of dexamethasone pre-treated U937 cells to 25 nm of TiO2 NPs induced a significant increase in cell survival at only 100 mg/ml particle concentration, increase in viability of SHYS5Y cells were observed at all concentrations against 10 nm particle challenge. Our study demonstrated that exposure of SHYS5Y to TiO2 NPs for 24 hours regularly induced reduction of cell viability. We also found similar dose-related effects of TiO2 NPs in reducing cell survival in IM9 cells. This study clearly indicated that FBS is an effective dispersing agent for TiO2 NPs and increased TiO2 toxicity in all cell lines. NAC and neopterin significantly protected the SHYS5Y cell against the putative cytotoxic effects of TiO2 NPs.

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Review on the role of antioxidant supplementation against oxidative stress: a human and animal approach to male fertility

Research Society and Development ◽

10.33448/rsd-v11i1.25191 ◽

2022 ◽

Vol 11 (1) ◽

pp. e43211125191

Author(s):

Luana Nayara Gallego Adami ◽

Valter Luiz Maciel Junior ◽

João Diego Losano

Keyword(s):

Oxidative Stress ◽

Male Infertility ◽

Male Fertility ◽

Sperm Quality ◽

Human Sperm ◽

Original Data ◽

Experimental Models ◽

Antioxidant Supplementation ◽

And Function

Male infertility is one important factor among the multifactorial causes of couple infertility, being oxidative stress one of the main related sources. Sperm is a specialized cell extremely susceptible to stress. To understand and mitigate this event, many studies have used different antioxidants, orally or in vitro supplementation, trying to improve sperm quality and function. Considering the extensive available literature regarding approaches and attempts to solve male fertility issues, the aim of this review is evaluating the effects of antioxidant supplementation on sperm, in both humans and experimental models with animals. This review selected original data from PubMed. The keywords used were: antioxidant, sperm, male fertility, antioxidant supplementation, male infertility; and the term "rodents" was added to the descriptors “antioxidant” and “male fertility”. Only studies published in indexed journals, in English, between 2015 and 2019 were included. This review involves i) human sperm and ii) rodent sperm. For the human approach, the search retrieved 496 articles and 80 were included, among which 28 studies were of in vitro antioxidant supplementation, 19 involved oral antioxidant supplementation and the remaining 33 concerned quantification of oxidants and antioxidants already present in the seminal samples. For the rodent approach, 152 articles were retrieved and 52 were included: 3 of varicocele, 11 of diabetes, 10 of therapeutic drugs, 3 of physical exercise, 10 of environmental exposure and 3 of heat stress. The remaining studies involved oxidative stress status in experimental models. Antioxidants use for reproductive purposes is increasing in an attempt to achieve better gametes and embryos. Vitamins C, B and E, selenium and zinc are the most commonly used antioxidants, with remarkable evidences in improving pathophysiological seminal conditions.

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Oxidative Stress and Male Fertility: Role of Antioxidants and Inositols

Antioxidants ◽

10.3390/antiox10081283 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1283

Author(s):

Maria Nunzia De Luca ◽

Marisa Colone ◽

Riccardo Gambioli ◽

Annarita Stringaro ◽

Vittorio Unfer

Keyword(s):

Oxidative Stress ◽

Male Fertility ◽

Sperm Quality ◽

Synergistic Effects ◽

Steroidogenic Enzyme ◽

Transduction Mechanisms ◽

One Year ◽

Global Health Problem ◽

Male Factors

Infertility is defined as a couple’s inability to conceive after at least one year of regular unprotected intercourse. This condition has become a global health problem affecting approximately 187 million couples worldwide and about half of the cases are attributable to male factors. Oxidative stress is a common reason for several conditions associated with male infertility. High levels of reactive oxygen species (ROS) impair sperm quality by decreasing motility and increasing the oxidation of DNA, of protein and of lipids. Multi-antioxidant supplementation is considered effective for male fertility parameters due to the synergistic effects of antioxidants. Most of them act by decreasing ROS concentration, thus improving sperm quality. In addition, other natural molecules, myo-inositol (MI) and d-chiro–inositol (DCI), ameliorate sperm quality. In sperm cells, MI is involved in many transduction mechanisms that regulate cytoplasmic calcium levels, capacitation and mitochondrial function. On the other hand, DCI is involved in the downregulation of steroidogenic enzyme aromatase, which produces testosterone. In this review, we analyze the processes involving oxidative stress in male fertility and the mechanisms of action of different molecules.

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Zinc Homeostasis in Bone: Zinc Transporters and Bone Diseases

International Journal of Molecular Sciences ◽

10.3390/ijms21041236 ◽

2020 ◽

Vol 21 (4) ◽

pp. 1236 ◽

Cited By ~ 4

Author(s):

Tongling Huang ◽

Guoyong Yan ◽

Min Guan

Keyword(s):

Cell Types ◽

Bone Diseases ◽

Zinc Transporter ◽

Zinc Homeostasis ◽

Zinc Transporters ◽

Bone Homeostasis ◽

Microstructural Stability ◽

Physiological Processes ◽

Zip Family ◽

Intracellular Compartments

Zinc is an essential micronutrient that plays critical roles in numerous physiological processes, including bone homeostasis. The majority of zinc in the human body is stored in bone. Zinc is not only a component of bone but also an essential cofactor of many proteins involved in microstructural stability and bone remodeling. There are two types of membrane zinc transporter proteins identified in mammals: the Zrt- and Irt-like protein (ZIP) family and the zinc transporter (ZnT) family. They regulate the influx and efflux of zinc, accounting for the transport of zinc through cellular and intracellular membranes to maintain zinc homeostasis in the cytoplasm and in intracellular compartments, respectively. Abnormal function of certain zinc transporters is associated with an imbalance of bone homeostasis, which may contribute to human bone diseases. Here, we summarize the regulatory roles of zinc transporters in different cell types and the mechanisms underlying related pathological changes involved in bone diseases. We also present perspectives for further studies on bone homeostasis-regulating zinc transporters.

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Melatonin rescues impaired penetration ability of human spermatozoa induced by mitochondrial dysfunction

Reproduction ◽

10.1530/rep-19-0231 ◽

2019 ◽

Vol 158 (5) ◽

pp. 465-475 ◽

Cited By ~ 3

Author(s):

Xue-Ying Zhang ◽

Yi-Meng Xiong ◽

Ya-Jing Tan ◽

Li Wang ◽

Rong Li ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Male Fertility ◽

Sperm Quality ◽

Fertilization Failure ◽

Respiratory Capacity ◽

Fertilization Rates ◽

Penetration Ability ◽

Poor Fertilization ◽

Mitochondrial Respiratory

Fertilization failure often occurs during in vitro fertilization (IVF) cycles despite apparently normal sperm and oocytes. Accumulating evidence suggests that mitochondria play crucial roles in the regulation of sperm function and male fertility. 3-Nitrophthalic acid (3-NPA) can induce oxidative stress in mitochondria, and melatonin, as an antioxidant, can improve mitochondrial function by reducing mitochondrial oxidative stress. The role of sperm mitochondrial dysfunction in fertilization failure during IVF is unclear. The present study revealed that spermatozoa with low, or poor, fertilization rates had swollen mitochondria, increased mitochondria-derived ROS, and attenuated mitochondrial respiratory capacity. 3-NPA treatment enhanced mitochondrial dysfunction in sperm. Spermatozoa with poor fertilization rates, and spermatozoa treated with 3-NPA, had reduced penetration ability. The concentration of melatonin was decreased in semen samples with low and poor fertilization rates. Melatonin, not only decreased excessive mitochondria-derived ROS, but also ‘rescued’ the reduced penetration capacity of spermatozoa treated with 3-NPA. Taken together, the study suggested that mitochondria-derived ROS and mitochondrial respiratory capacity are independent bio-markers for sperm dysfunction, and melatonin may be useful in improving sperm quality and overall male fertility.

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Protection Against Oxidative Stress-Induced Retinal Cell Death by Compounds Isolated From Ehretia asperula

Natural Product Communications ◽

10.1177/1934578x211067986 ◽

2021 ◽

Vol 16 (12) ◽

pp. 1934578X2110679

Author(s):

Tam Thi Le ◽

Tae Kyeom Kang ◽

Ha Thi Do ◽

Trong Duc Nghiem ◽

Wook-Bin Lee ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

Cell Viability ◽

Rosmarinic Acid ◽

Retinal Cell ◽

Published Data ◽

Protective Effects ◽

Chemical Structures ◽

Wide Range ◽

Ethanolic Extracts

Ehretia asperula ( E asperula) is a well-known traditional medicinal plant in Vietnam with potent activity against a wide range of diseases, including hepatitis B and various cancers. Although E asperula has been used in traditional medicine, the efficacy of E asperula and its bioactive components on retinal degenerative diseases has not been fully evaluated. In present this study, we found that ethanolic extracts of E asperula increased cell viability in retinal precursor cells exposed to glutamate/BSO-induced excitotoxicity/oxidative stress. The major responsible bioactive compounds were rosmarinic acid and methylrosmarinic acid. First, 10 known compounds were isolated from E asperula leaves. Their chemical structures were determined using 1D and 2D nuclear magnetic resonance, and compared with published data. Using high-performance liquid chromatography, we determined the content of 4 compounds in E asperula extract: rosmarinic acid, lithospermic acid B, astragalin, and kaempferol 3-rutinoside. The most abundant of these compounds was lithospermic acid B. The protective effects of the pure compounds and ethanolic extracts against excitotoxicity and oxidative stress-induced retinal cell death were tested in R28 cells. Both 70% and 95% ethanolic extracts of E asperula increased cell viability in these conditions. Rosmarinic acid and methyl rosmarinic acid were more effective at protecting against retinal cell death and elevated reactive oxygen species in cells subjected to glutamate/BSO-induced excitotoxicity/oxidative stress. These findings suggested that E asperula could potentially be used to treat retinal degeneration.

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