OBJECTIVE: Arsenic (As) and fluoride (F) are two of the most common elements contaminating groundwater resources. A growing number of studies have found that As and F can cause neurotoxicity in infants and children, leading to cognitive, learning, and memory impairments. However, early biomarkers of learning and memory impairment induced by As and/or F remain unclear. In the present study, the mechanisms by which As and/or F cause learning memory impairment are explored at the multi-omics level (microbiome and metabolome). METHODS: We stablished an SD rats model exposed to arsenic and/or fluoride from intrauterine to adult period. RESULTS: Arsenic and/fluoride exposed groups showed reduced neurobehavioral performance and lesions in the hippocampal CA1 region. 16S rRNA gene sequencing revealed that As and/or F exposure significantly altered the composition and diversity of the gut microbiome，featuring the Lachnospiraceae_NK4A136_group, Ruminococcus_1, Prevotellaceae_NK3B31_group, [Eubacterium]_xylanophilum_group. Metabolome analysis showed that As and/or F-induced learning and memory impairment may be related to tryptophan, lipoic acid, glutamate, gamma-aminobutyric acidergic (GABAergic) synapse, and arachidonic acid (AA) metabolism. The gut microbiota, metabolites, and learning memory indicators were significantly correlated. CONCLUSION Learning memory impairment triggered by As and/or F exposure may be mediated by different gut microbes and their associated metabolites.
Rats ; Animals ; Arsenic/toxicity* ; Fluorides ; RNA, Ribosomal, 16S/genetics* ; Rats, Sprague-Dawley ; Metabolome ; Microbiota

Chronic kidney disease (CKD) is suffered progressive loss of kidney function lasting more than 3 months and is classified according to the degree of kidney damage (level of proteinuria) and the decreased glomerular filtration rate (GFR). The most severe form of CKD is end-stage renal disease. The prevalence of CKD is high with fast growth rate and the disease burden has become increasingly serious. CKD has become an important public health problem threatening human health. The etiology of CKD is complex. In addition to genetic factors, environmental factors are an important cause of CKD. With the development of industrialization, environmental metal pollution has become increasingly severe, and its impact on human health has received widespread attention. A large number of studies have shown that metals such as lead, cadmium, and arsenic can accumulate in the kidney, which can cause damage to the structure and function of the kidney, and play an important role in the development of CKD. Therefore, summarizing the epidemiological research progress in the relationship between arsenic, cadmium, lead, and other metal exposures and kidney diseases can provide new ideas for the prevention and control of kidney diseases caused by metal exposure.
Humans ; Cadmium/toxicity* ; Arsenic/toxicity* ; Kidney ; Renal Insufficiency, Chronic/epidemiology* ; Kidney Failure, Chronic

Devitalization has been widely used in the root canal therapy of primary and permanent teeth in China more than ten years ago. With the development of local anesthetic drugs and injection technologies, this treatment method with high potential risks has been gradually abandoned. However, a questionnaire survey targeted all the participants at the 2018 China Pediatric Dentistry Conference showed that the devitalizer utilization proportion was still as high as 38.1% (383/1 005), even though the ratio was much lower than 75.5% (105/139) in 2003. These doctors had pay more attention to tissue burn caused by devitalizer marginal leakage or direct leakage, and know how to identify and handle with devitalizer burn. Devitalizers were usually made of arsenic trioxide, metal arsenic or paraformaldehyde, which have cytotoxicity, allergenicity, mutagenicity, carcinogenicity, and teratogenic effects on animals. Marginal leakage of devitalizers have high risks of causing soft and hard tissue necrosis. Most of the dentists have an understanding of the potential damages of arsenic containing devitalizers, so they will choose parafor maldehyde with relatively less toxicity. Paraformaldehyde has a certain self limitation, and there are few cases reported, so some dentists lack of vigilance. Paraformaldehyde can also causes tissue necrosis if leakage happens, and the treatment methods are similar to that of arsenic containing devitalizers. When handling with devitalizers burn, the necrosed soft and hard tissue, for example gingiva, alveolar bone or teeth that cannot keep, must be completely removed until fresh blood appears, then rinse with large amount of saline and seal with iodoform gauze. This paper described two cases of devitalizer burn during the root canal treatment of primary molars, both of the doctors failed to identify the devitalizer burn symptoms in the early stage, thus didn't do proper treatments immediately after burning. Resulting in the necrosis of large area of gingiva and alveolar bone, loss of primary molars and permanent tooth germs 1-2 months after devitalizer burn. This paper reported these two cases in detail in order to warn dentists the high risks of using any kind of devitalizers, help them learn how to identify and treat devitalizer burn, and remind them to stop using devitalizers as soon as possible.
Arsenic/toxicity* ; China ; Dental Pulp Devitalization ; Humans ; Necrosis ; Root Canal Therapy ; Tooth Germ ; Tooth Loss/chemically induced* ; Tooth, Deciduous

Arsenic is a non-metallic element, and the International Agency for Research on Cancer has identified arsenic and its compounds as carcinogens. Arsenic and its compounds can be absorbed through the respiratory tract, skin and digestive tract, distributed in the liver, kidney, lung and skin, and cause damage. Non-coding RNAs are closely related to arsenic-induced nervous system disorders, cell necrosis, reproductive toxicity, and carcinogenesis. In recent years, the network regulation of microRNAs (miRNAs) , long non-coding RNAs (lncRNAs) , and circular RNAs (circRNAs) among non-coding RNAs in various diseases induced by arsenic has become a new research field. This paper summarizes the existing scientific research results, and expounds the mechanism of miRNAs, lncRNAs and circRNAs in arsenic toxicity, and provides basic data and theoretical basis for the prevention and treatment of arsenic poisoning.
Arsenic/toxicity* ; Arsenic Poisoning ; Humans ; MicroRNAs/genetics* ; RNA, Circular ; RNA, Long Noncoding/genetics*

Arsenic/toxicity* ; Bangladesh ; Female ; Humans ; Infant, Newborn ; Pregnancy ; Premature Birth/chemically induced* ; Rural Population ; Zinc

BACKGROUND: Arsenic is a developmental neurotoxicant. It means that its neurotoxic effect could occur in offspring by maternal arsenic exposure. Our previous study showed that developmental arsenic exposure impaired social behavior and serotonergic system in C3H adult male mice. These effects might affect the next generation with no direct exposure to arsenic. This study aimed to detect the social behavior and related gene expression changes in F2 male mice born to gestationally arsenite-exposed F1 mice. METHODS: Pregnant C3H/HeN mice (F0) were given free access to tap water (control mice) or tap water containing 85 ppm sodium arsenite from days 8 to 18 of gestation. Arsenite was not given to F1 or F2 mice. The F2 mice were generated by mating among control F1 males and females, and arsenite-F1 males and females at the age of 10 weeks. At 41 weeks and 74 weeks of age respectively, F2 males were used for the assessment of social behavior by a three-chamber social behavior apparatus. Histological features of the prefrontal cortex were studied by ordinary light microscope. Social behavior-related gene expressions were determined in the prefrontal cortex by real time RT-PCR method. RESULTS: The arsenite-F2 male mice showed significantly poor sociability and social novelty preference in both 41-week-old group and 74-week-old group. There was no significant histological difference between the control mice and the arsenite-F2 mice. Regarding gene expression, serotonin receptor 5B (5-HT 5B) mRNA expression was significantly decreased (p < 0.05) in the arsenite-F2 male mice compared to the control F2 male mice in both groups. Brain-derived neurotrophic factor (BDNF) and dopamine receptor D1a (Drd1a) gene expressions were significantly decreased (p < 0.05) only in the arsenite-F2 male mice of the 74-week-old group. Heme oxygenase-1 (HO-1) gene expression was significantly increased (p < 0.001) in the arsenite-F2 male mice of both groups, but plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cyclooxygenase-2 (COX-2) gene expression were not significantly different. Interleukin-1β (IL-1β) mRNA expression was significantly increased only in 41-week-old arsenite-F2 mice. CONCLUSIONS These findings suggest that maternal arsenic exposure affects social behavior in F2 male mice via serotonergic system in the prefrontal cortex. In this study, COX-2 were not increased although oxidative stress marker (HO-1) was increased significantly in arsnite-F2 male mice.
Animals ; Arsenic/toxicity* ; Arsenites/toxicity* ; Behavior, Animal/drug effects* ; Environmental Pollutants/toxicity* ; Female ; Gene Expression/drug effects* ; Genetic Markers ; Male ; Maternal Exposure/adverse effects* ; Mice ; Mice, Inbred C3H ; Oxidative Stress/genetics* ; Prefrontal Cortex/drug effects* ; Pregnancy ; Prenatal Exposure Delayed Effects/psychology* ; Reverse Transcriptase Polymerase Chain Reaction ; Serotonin/metabolism* ; Social Behavior ; Sodium Compounds/toxicity*

High levels (> 100 ug/L) of arsenic are known to cause lung cancer; however, whether low (≤ 10 ug/L) and medium (10 to 100 ug/L) doses of arsenic will cause lung cancer or other lung diseases, and whether arsenic has dose-dependent or threshold effects, remains unknown. Summarizing the results of previous studies, we infer that low- and medium-concentration arsenic cause lung diseases in a dose-dependent manner. Arsenic trioxide (ATO) is recognized as a chemotherapeutic drug for acute promyelocytic leukemia (APL), also having a significant effect on lung cancer. The anti-lung cancer mechanisms of ATO include inhibition of proliferation, promotion of apoptosis, anti-angiogenesis, and inhibition of tumor metastasis. In this review, we summarized the role of arsenic in lung disease from both pathogenic and therapeutic perspectives. Understanding the paradoxical effects of arsenic in the lungs may provide some ideas for further research on the occurrence and treatment of lung diseases.
Animals ; Arsenic/toxicity* ; Dose-Response Relationship, Drug ; Humans ; Lung/pathology* ; Lung Neoplasms/drug therapy* ; Mice

Well water could be a stable source of drinking water. Recently, the use of well water as drinking water has been encouraged in developing countries. However, many kinds of disorders caused by toxic elements in well drinking water have been reported. It is our urgent task to resolve the global issue of element-originating diseases. In this review article, our multidisciplinary approaches focusing on oncogenic toxicities and disturbances of sensory organs (skin and ear) induced by arsenic and barium are introduced. First, our environmental monitoring in developing countries in Asia showed elevated concentrations of arsenic and barium in well drinking water. Then our experimental studies in mice and our epidemiological studies in humans showed arsenic-mediated increased risks of hyperpigmented skin and hearing loss with partial elucidation of their mechanisms. Our experimental studies using cultured cells with focus on the expression and activity levels of intracellular signal transduction molecules such as c-SRC, c-RET, and oncogenic RET showed risks for malignant transformation and/or progression arose from arsenic and barium. Finally, our original hydrotalcite-like compound was proposed as a novel remediation system to effectively remove arsenic and barium from well drinking water. Hopefully, comprehensive studies consisting of (1) environmental monitoring, (2) health risk assessments, and (3) remediation will be expanded in the field of environmental health to prevent various disorders caused by environmental factors including toxic elements in drinking water.
Animals ; Arsenic ; toxicity ; Barium ; toxicity ; Drinking Water ; analysis ; Environmental Exposure ; Environmental Health ; Environmental Monitoring ; Humans ; Mice ; Water Pollutants, Chemical ; toxicity ; Water Wells

BACKGROUND: More than 140 million people drink arsenic-contaminated groundwater. It is unknown how much arsenic exposure is necessary to cause neurological impairment. Here, we evaluate the relationship between neurological impairments and the arsenic concentration in drinking water (ACDW). PARTICIPANTS AND METHODS: A cross-sectional study design was employed. We performed medical examinations of 1867 residents in seven villages in the Thabaung township in Myanmar. Medical examinations consisted of interviews regarding subjective neurological symptoms and objective neurological examinations of sensory disturbances. For subjective neurological symptoms, we ascertained the presence or absence of defects in smell, vision, taste, and hearing; the feeling of weakness; and chronic numbness or pain. For objective sensory disturbances, we examined defects in pain sensation, vibration sensation, and two-point discrimination. We analyzed the relationship between the subjective symptoms, objective sensory disturbances, and ACDW. RESULTS: Residents with ACDW ≥ 10 parts per billion (ppb) had experienced a "feeling of weakness" and "chronic numbness or pain" significantly more often than those with ACDW < 10 ppb. Residents with ACDW ≥ 50 ppb had three types of sensory disturbances significantly more often than those with ACDW < 50 ppb. In children, there was no significant association between symptoms or signs and ACDW. CONCLUSION Subjective symptoms, probably due to peripheral neuropathy, occurred at very low ACDW (around 10 ppb). Objective peripheral nerve disturbances of both small and large fibers occurred at low ACDW (> 50 ppb). These data suggest a threshold for the occurrence of peripheral neuropathy due to arsenic exposure, and indicate that the arsenic concentration in drinking water should be less than 10 ppb to ensure human health.
Adolescent ; Adult ; Arsenic ; analysis ; toxicity ; Cross-Sectional Studies ; Dietary Exposure ; adverse effects ; Dose-Response Relationship, Drug ; Drinking Water ; adverse effects ; chemistry ; Female ; Groundwater ; chemistry ; Humans ; Male ; Middle Aged ; Myanmar ; epidemiology ; Peripheral Nervous System Diseases ; chemically induced ; epidemiology ; physiopathology ; Sensation Disorders ; chemically induced ; epidemiology ; physiopathology ; Water Pollutants, Chemical ; analysis ; toxicity ; Young Adult

The aim of the present study is to evaluate the ability and mechanism by which grape seed procyanidin extract (GSPE) relieves arsenic trioxide (As2O3)-induced renal inflammatory injury. Therefore, male Kunming mice were treated with As2O3 and/or GSPE by gavage for 5 weeks. Mice were then sacrificed and inflammatory cytokines of kidneys were examined by ELISA, whereas the expression levels of molecules involved in the nuclear factor (NF)-κB signaling pathway were evaluated by both qRT-PCR and Western blot. Our results indicate that GSPE prevents As2O3-mediated renal inflammatory injury by inhibiting activation of the NF-κB signaling pathway and inflammatory cytokine production, while promoting expression of anti-inflammatory cytokines.
Animals ; Arsenic ; toxicity ; Grape Seed Extract ; therapeutic use ; Inflammation ; chemically induced ; drug therapy ; Kidney Diseases ; chemically induced ; drug therapy ; Male ; Mice ; Proanthocyanidins ; therapeutic use