BACKGROUND: As research progresses, there is a growing body of evidence indicating that urinary metallothionein (MT) levels may be elevated in individuals exposed to cadmium (Cd). This study aimed to investigate the potential association between urinary MT levels and causes of mortality among residents of the Kakehashi River Basin who have been exposed to Cd. METHOD: The study involved a total of 1,398 men and 1,731 women were conducted between 1981 and 1982, with follow-up until November 2016. The study employed the Cox proportional-hazards model to examine the association between higher urinary MT concentrations and the risk of all-cause or cause-specific mortality within the population. Furthermore, the Fine and Gray competing risks regression model was used to evaluate the links between specific causes of death. RESULTS: The findings revealed that elevated urinary MT concentrations were linked to increased all-cause mortality and higher mortality rates from renal and urinary tract diseases across all participants. Specifically, in men, higher urinary MT levels were associated with elevated all-cause mortality, while in women, increased concentrations were linked to higher mortality from endocrine, nutritional, and metabolic diseases, as well as cardiovascular diseases. Even after adjusting for competing risks, higher urinary MT concentrations were associated with tumor-related mortality in men and continued to be associated with cardiovascular disease mortality in women. CONCLUSIONS In conclusion, the results suggest that women may face a greater risk of adverse health effects due to prolonged exposure to Cd. Urinary MT levels could potentially serve as a biomarker for mortality from these diseases in populations chronically exposed to Cd.
Humans ; Male ; Female ; Cadmium/urine* ; Japan/epidemiology* ; Metallothionein/metabolism* ; Middle Aged ; Cause of Death ; Adult ; Follow-Up Studies ; Aged ; Environmental Exposure/analysis* ; Proportional Hazards Models

OBJECTIVE: Aloin, the main active component in Aloe vera (L.) Burm. f., has shown promising anti-tumor effects. This study investigated the impact of aloin in lung squamous cell carcinoma (LUSC) and explored its functional mechanism. METHODS: We analyzed the viability, migration, invasion, proliferation, and apoptosis of two LUSC cell lines after treatment with aloin. Target molecules of aloin and downstream target transcripts of nuclear receptor subfamily 3 group C member 2 (NR3C2) were predicted by bioinformatics. The biological functions of NR3C2 and metallothionein 1 M (MT1M) in the malignant properties of LUSC cells were determined. A co-culture system of LUSC cells with monocyte-derived macrophages was constructed. Mouse xenograft tumor models were generated to analyze the functions of aloin and NR3C2 in the tumorigenic activity of LUSC cells and macrophage polarization in vivo. RESULTS: Aloin suppressed malignant properties of LUSC cells in vitro. However, these effects were negated by the silencing of NR3C2. NR3C2 was found to activate MT1M transcription by binding to its promoter. Additional upregulation of MT1M suppressed the malignant behavior of LUSC cells augmented by NR3C2 silencing. Analysis of the M1 and M2 markers/cytokines in the macrophages or the culture supernatant revealed that aloin treatment or MT1M overexpression in LUSC cells enhanced M1 polarization while suppressing M2 polarization of macrophages, whereas NR3C2 silencing led to reverse trends. Consistent findings were reproduced in vivo. CONCLUSION This study demonstrated that aloin activates the NR3C2/MT1M axis to suppress the malignant behavior of LUSC cells and M2 macrophage polarization. Please cite this article as: Chen YN, Lu JY, Gao CF, Fang ZR, Zhou Y. Aloin blocks the malignant behavior of lung squamous cell carcinoma cells and M2 macrophage polarization by modulating the NR3C2/MT1M axis. J Integr Med. 2025; 23(2): 195-208.
Lung Neoplasms/metabolism* ; Humans ; Animals ; Cell Line, Tumor ; Carcinoma, Squamous Cell/metabolism* ; Mice ; Macrophages/drug effects* ; Emodin/analogs & derivatives* ; Metallothionein/genetics* ; Cell Proliferation/drug effects* ; Cell Movement/drug effects* ; Apoptosis/drug effects* ; Receptors, Glucocorticoid/genetics*

Cadmium/metabolism* ; Kidney ; Cells, Cultured ; Mitochondria ; Metallothionein/metabolism* ; Liver

Metallothionein (MT) plays a significant role in heavy metal removal, antioxidant defense, and immune regulation. The current predominant approach for obtaining natural MT is extraction from tissue, which often entails complex procedures resulting in limited yields. In recent years, researchers have adopted the strategy of fusing labels such as GST or His for the heterologous expression of MT. However, a challenge in industrial production arises from the subsequent removal of these labels, which often leads to a significant reduction in the yield. The fusion with elastin-like polypeptides (ELPs) offers a promising solution for achieving soluble expression of the target protein, while providing a simple and fast purification process. In this study, ELP was fused with MT, which significantly up-regulated the soluble expression of MT. The fusion protein ELP-MT with the purity above 97% was obtained efficiently and simply by inverse transition cycling (ITC). ELP-MT exhibited a remarkable 2,2'-azinobis(3-ethylbenzothiazoline-6- sulfonic acid) ammonium salt (ABTS) scavenging activity, with the half maximal inhibitory concentration (IC₅₀) of 0.77 μmol/L, which was 53.7 times that of the vitamin E derivative Trolox. In addition, the fusion protein demonstrated strong 1,1-diphenyl-2-trinitrohydrazine (DPPH) scavenging ability. Furthermore, ELP-MT had no toxicity to the proliferation and promoted the adhesion and migration of NIH/3T3 cells. All these results indicated that ELP-MT had good biocompatibility. We constructed the fusion protein ELP-MT combining the unique properties of MT and elastin, laying a technical foundation for the large-scale production of recombinant MT and facilitating the applications in food, health supplement, and cosmetic industries.
Metallothionein/metabolism* ; Elastin/chemistry* ; Recombinant Fusion Proteins/pharmacology* ; Mice ; Animals ; Peptides/metabolism* ; Escherichia coli/metabolism* ; NIH 3T3 Cells

OBJECTIVES: To investigate the time-dependent expression of metallothionein （MT） 1A mRNA and MT2A mRNA in contused skeletal muscle of rats. METHODS: A total of 54 Sprague-Dawley rats were used in this study. The rats were divided into two parts: control group （n=6） and contusion groups （0.5, 1, 6, 12, 18, 24, 30, and 36 h after contusion, n=6）. Total RNA was extracted from skeletal muscle. The expression levels of MT1A mRNA and MT2A mRNA were detected by SYBR Green I real-time PCR. RESULTS: The expression trends of the two potential marker genes were related to wound age. In addition to 0.5 h, there were significant contrasts between the control group and contused group （P<0.05）, about the expression levels of MT1A mRNA and MT2A mRNA in different phases. As the extension of wound age, the relative expression of MT1A mRNA and MT2A mRNA at 1 h, 6 h, 12 h and 18 h after contusion demonstrated upgrade tendency until its expression levels in 18 h peak with 239.41±15.20 and 717.42±50.76, respectively. When time extends to 24 h after injury, the expression of above two marks decreased, respectively. The MT1A mRNA and MT2A mRNA expression levels increased at 30 h and then decreased. CONCLUSIONS Determination of MT1A mRNA and MT2A mRNA levels by real-time PCR may be useful for the estimation of wound age.
Animals ; Contusions/pathology* ; Gene Expression Regulation ; Genetic Markers ; Metallothionein ; Muscle, Skeletal/metabolism* ; RNA, Messenger/metabolism* ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Time Factors ; Wound Healing

BACKGROUND: Reactive oxygen species (ROS) and antioxidants are associated with maintenance of cellular function and metabolism. Nuclear factor-E2-related factor 1 (NFE2L1, Nrf1) is known to regulate the expression of a number of genes involved in oxidative stress and inflammation. The purpose of this study was to examine the effects of NFE2L1 on the response to oxidative stress in osteoblastic MC3T3-E1 cells. METHODS: The murine calvaria-derived MC3T3-E1 cell line was exposed to lipopolysaccharide (LPS) for oxidative stress induction. NFE2L1 effects were evaluated using small interfering RNA (siRNA) for NFE2L1 mRNA. ROS generation and the levels of known antioxidant enzyme genes were assayed. RESULTS: NFE2L1 expression was significantly increased 2.4-fold compared to the control group at 10 µg/mL LPS in MC3T3-E1 cells (P<0.05). LPS increased formation of intracellular ROS in MC3T3-E1 cells. NFE2L1 knockdown led to an additional increase of ROS (20%) in the group transfected with NFE2L1 siRNA compared with the control group under LPS stimulation (P<0.05). RNA interference of NFE2L1 suppressed the expression of antioxidant genes including metallothionein 2, glutamatecysteine ligase catalytic subunit, and glutathione peroxidase 1 in LPS-treated MC3T3-E1 cells. CONCLUSION: Our results suggest that NFE2L1 may have a distinct role in the regulation of antioxidant enzymes under inflammation-induced oxidative stress in MC3T3-E1 osteoblastic cells.
Antioxidants ; Catalytic Domain ; Cell Line ; Glutathione Peroxidase ; Inflammation ; Metabolism ; Metallothionein ; NF-E2-Related Factor 1 ; Osteoblasts* ; Oxidative Stress* ; Reactive Oxygen Species ; RNA Interference ; RNA, Messenger ; RNA, Small Interfering

To evaluate the effect of diet on metabolic control and zinc metabolism in patients with type 2 diabetes mellitus (T2DM). One-week balanced diet was provided to 10 Brazilians patients with T2DM. Nutritional assessment, laboratorial parameters and expression of zinc transporter and inflammatory genes in peripheral blood mononuclear cells (PBMC) were performed. Healthy non-diabetic subjects of the same demographic were recruited to provide baseline data. Diabetic patients had higher body mass index and greater fasting plasma glucose, plasma tumor necrosis factor alpha (TNFalpha) and plasma interleukin 6 (IL6) levels compared with healthy subjects. In addition, the expression of transporters 4 (ZnT4) mRNA was lower and IL6 mRNA was higher in PBMC of these diabetic patients than in healthy subject. One week after a balanced diet was provided, fasting plasma glucose decreased significantly as did TNFalpha, IL6 and Metallothionein 1 (MT1) mRNAs. No change was observed in zinc transporter expression in PBMC after the dietary intervention. A healthy eating pattern maintained for one week was able to improve metabolic control of diabetic patients by lowering fasting plasma glucose. This metabolic control may be related to down-regulation of zinc-related transcripts from PBMCs, as TNFalpha, IL6 and MT1 mRNA.
Blood Glucose ; Body Mass Index ; Diabetes Mellitus, Type 2 ; Diet* ; Down-Regulation ; Eating ; Fasting ; Humans ; Inflammation* ; Interleukin-6 ; Metabolism* ; Metallothionein ; Nutrigenomics ; Nutrition Assessment ; Plasma ; RNA, Messenger ; Tumor Necrosis Factor-alpha ; Zinc*

Zinc has been considered as a vital constituent of proteins, including enzymes. Mobile reactive zinc (Zn2+) is the key form of zinc involved in signal transductions, which are mainly driven by its binding to proteins or the release of zinc from proteins, possibly via a redox switch. There has been growing evidence of zinc's critical role in cell signaling, due to its flexible coordination geometry and rapid shifts in protein conformation to perform biological reactions. The importance and complexity of Zn2+ activity has been presumed to parallel the degree of calcium's participation in cellular processes. Whole body and cellular Zn2+ levels are largely regulated by metallothioneins (MTs), Zn2+ importers (ZIPs), and Zn2+ transporters (ZnTs). Numerous proteins involved in signaling pathways, mitochondrial metabolism, and ion channels that play a pivotal role in controlling cardiac contractility are common targets of Zn2+. However, these regulatory actions of Zn2+ are not limited to the function of the heart, but also extend to numerous other organ systems, such as the central nervous system, immune system, cardiovascular tissue, and secretory glands, such as the pancreas, prostate, and mammary glands. In this review, the regulation of cellular Zn2+ levels, Zn2+-mediated signal transduction, impacts of Zn2+ on ion channels and mitochondrial metabolism, and finally, the implications of Zn2+ in health and disease development were outlined to help widen the current understanding of the versatile and complex roles of Zn2+.
Central Nervous System ; Heart ; Immune System ; Ion Channels ; Mammary Glands, Human ; Metabolism ; Metallothionein ; Oxidation-Reduction ; Pancreas ; Prostate ; Protein Conformation ; Signal Transduction ; Zinc*

Metallothionein (MT) is a kind of metal binding protein. As an important member in metallothionein family, MT-I/II regulates metabolism and detoxication of brain metal ion and scavenges free radicals. It is capable of anti-inflammatory response and anti-oxidative stress so as to protect the brain tissue. During the repair process of brain injury, the latest study showed that MT-I/II could stimulate brain anti-inflammatory factors, growth factors, neurotrophic factors and the expression of the receptor, and promote the extension of axon of neuron, which makes contribution to the regeneration of neuron and has important effect on the recovery of brain injury. Based on the findings, this article reviews the structure, expression, distribution, adjustion, function, mechanism in the repair of brain injury of MT-I/II and its application prospect in forensic medicine. It could provide a new approach for the design and manufacture of brain injury drugs as well as for age estimation of the brain injury.
Animals ; Astrocytes/metabolism* ; Brain/metabolism* ; Brain Injuries/pathology* ; Cytokines/metabolism* ; Forensic Medicine/methods* ; Gene Expression Regulation/drug effects* ; Humans ; Metallothionein/physiology* ; Neurons/metabolism* ; Neuroprotective Agents/pharmacology* ; Oxidative Stress/drug effects*

OBJECTIVE[corrected] To assess the effects of metallothionein on myocyte apoptosis and energy supply of isolated rabbit heart muscle during perfusion with ropivacaine..

METHODSSixty New Zealand white male rabbits were randomized into 3 equal groups. In group I, the rabbits received a intreaperitioneal injection of distilled water 24 h before isolation of the heart with perfusion by Langendoff model; in group II, distilled water was injected intreaperitioneally, and 24 h later the heart was isolated and perfused with Langendoff model and ropivacaine; in group III, 3.6% ZnSO(4) was injected intreaperitioneally and the isolated heart was perfused with Langendoff model and ropivacaine. The myocardial metallothionein content, myocyte apoptosis, and myocardial ATP, ADP and AMP content were detected.

RESULTSThe myocardial metallothionein content was significantly higher in group III than in the other two groups; the percent of myocyte apoptosis was the highest in group II, and was significantly higher in group III than in group I. The myocardial content of ATP was the highest in group I, and was significantly higher in group III than in group II.

CONCLUSIONMetallothionein can significantly inhibit myocyte apoptosis and alleviate energy supply disorder induced by ropivacaine.

Amides ; pharmacology ; Animals ; Apoptosis ; drug effects ; Energy Metabolism ; drug effects ; In Vitro Techniques ; Male ; Metallothionein ; pharmacology ; Myocardium ; cytology ; metabolism ; Myocytes, Cardiac ; cytology ; metabolism ; Perfusion ; Rabbits