Association of urinary arsenic with the oxidative DNA damage marker 8-hydroxy-2 deoxyguanosine: A meta-analysis

Meta-analysis of endocrine-disrupting chemical effects on earthworm functional traits

Endocrine-disrupting chemicals (EDCs) are ubiquitous emerging environmental contaminants. However, the comprehensive impact of EDCs on soil ecosystems, particularly on the model organism Eisenia fetida, remains inadequately understood due to disparate experimental and assessment methods. A meta-analysis was conducted to analyze the effects of EDCs on earthworm functional traits, including survival, behavior, growth, reproduction, and cellular responses. The analysis revealed that EDCs significantly impaired earthworm survival (-17.5%, p < 0.05), behavior (-62.2%, p < 0.001), growth (-11.5%, p < 0.001), and reproduction (-36.7%, p < 0.001). EDCs induced substantial oxidative stress, evidenced by a 36.5% (p < 0.001) increase in reactive oxygen species (ROS) production and elevated oxidative damage. The antioxidant defense system showed compensatory activation, with enhanced superoxide dismutase (10.0%) and catalase (8.90%) activities and glutathione levels (23.3%) (p < 0.001). The present study found chemical-specific toxicity patterns with heavy metals causing the most severe effects on behavior and reproduction. Toxicity profiles varied with exposure concentration and duration, revealing complex dose-response and temporal relationships. These findings provide crucial insights for the ecological risk assessment of EDCs and establish a foundation for developing targeted mitigation strategies. Furthermore, the findings highlight the importance of taking multiple endpoints into account when evaluating the toxicity of EDCs and suggest possible directions for future research.

Environmental pollutants and rectal cancer: The impact of water contamination

BACKGROUND

Water is a fundamental resource for life, and exposure to water contamination has far-reaching implications for an increased risk of tumor diseases.

METHODS

Studies of rectal and colorectal cancer related to water contamination were identified from the published literature in the PUBMED databases from 2010 to 2024.

RESULTS

This review provides a critical analysis of the current evidence, summarizing the association of water contamination, including industrial waste, pesticides, heavy metals, with rectal and colorectal cancer. It highlights their impact on rectal and colorectal cancer progression by underlying processes of DNA damage, chronic inflammation, and microbial contamination.

CONCLUSION

Rectal cancer is a significant global health concern with a strong association between environmental pollutants in water sources and increased incidence of rectal cancer. It is vital to identify how waster pollutants influence the development and progression of rectal cancer and formulate targeted preventive approaches and social interventions to decrease the disease's impact.

Recent advances in the clinical management of intoxication by five heavy metals: Mercury, lead, chromium, cadmium and arsenic

Metals have been used for many centuries, but their nutritional and toxic effects have been investigated since the last century. The common toxic heavy metals (THM) include mercury, lead, chromium cadmium, and arsenic. As human exposure to THM increasingly causes systemic and organ complications, it seems required to review the recent advances of treatment of the toxic metals. Despite the current knowledge of the hazards of heavy metals, there is still high incidents of their poisonings particularly in developing countries. In this review, after an introduction, we briefly describe the routes of exposure, clinical features and prognosis of each metal poisoning. Then, review the different treatments for each metal with particular attention to recent advances in the treatment of both acute and chronic poisonings. The main antidotes for all THM are still chelating agents, but new agents were developed over the past decades and have been used successfully for the THM poisonings. Dimercaptosuccinic acid (DMSA) known as succimer has been prescribed as a safe oral chelator in lead poisoning. Similarly, dimercapto-propanesulfonic acid (DMPS) has also revealed fewer side effects than the old chelating agents. The two are currently gaining increased acceptance among clinical toxicologists. However, there is no specific antidote for mercury poisoning. Dimercaprol is almost no longer used as an antidote of choice in the treatment of chronic THM poisoning. Comparison of clinical management of intoxication by the five heavy metals reveals similar treatment strategies. On the other hand, some of them require specific interventions to reduce the toxicity. Because of drawbacks in the application of commonly known chelating agents, treatment with bioactive compounds which have antioxidant and anti-inflammatory properties has been the subject of much interest in recent research. However, despite the promising results observed in experimental animals, clinical trials on their clinical therapeutic benefits have not been yet successful and need further studies to determine their efficacy and safety in humans. Development of less toxic chelating agents are still under investigations. Moreover, the development of orally administrable chelating agents for home health care would likely be of great interest for future research.

Effects of BRCA1 overexpression via the NRF2 / HO1 / NQO1 pathway on oral cancer cells proliferation, migration, and apoptosis

Objective

Herein, we explored the influences of breast cancer susceptibility gene 1 (BRCA1) overexpression on oral cancer cells proliferation, migration, and apoptosis via evaluation of its interactions with nuclear factor erythroid 2-like 2 (NRF2).

Design

CAL-27 and DOK cells were transfected with a BRCA1 overexpressing lentivirus. Next, we utilized Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) analyses to evaluate BRCA1, NRF2, and their target gene expressions. Using cell counting kit-8 (CCK-8) assessment, we assessed cell proliferation and a scratch test detected CAL-27 cell migration. Additionally, flow cytometry was employed used to examine cell apoptosis, while an enzyme-linked immunosorbent assa (ELISA) was employed for evaluation of 8-hydroxy-2'- deoxyguanosine (8-OHdG) expression. An immunohistochemical analysis was employed to determine the NRF2 target genes and Ki-67 expressions.

Results

BRCA1 overexpression increased the NRF2 and its target gene transcript and protein expressions. CCK-8 and scratch test results showed that BRCA1 overexpression decreased cell proliferation and weakened CAL-27 cell migratory ability. Flow cytometry results showed that BRCA1 overexpression promoted cell apoptosis in a time-dependent manner, while enzyme-linked immunosorbent assay results showed that BRCA1 overexpression decreased 8-OHdG expression levels in CAL-27 and DOK cells. Immunohistochemical analysis results showed higher expression of NRF2 target genes and Ki-67 in oral squamous cell carcinoma cells.

Conclusions

Experiments involving oral cancer cells confirmed that BRCA1 overexpression could up-regulate the NRF2 signalling pathway, reduce oxidative damage, and inhibit cell proliferation and other biological behaviours. The BRCA1 and NRF2 pathways might be associated with oral cancer occurrence and development.

Lycium barbarum berry extract improves female fertility against aging-related oxidative stress in the ovary

Reproductive aging in female mammals is characterized by ovarian senescence, leading to a significant fertility decline. Lycium barbarum berry, or goji berry, is a food and medicine that appears in various formulas for treating infertility in traditional Chinese medicine. We investigated the function of an aqueous extract of Lycium barbarum berry (LB extract) to improve health status, fertility, and offspring development during female aging. Aged female mice were supplemented with LB extract, and its effects on fertility, locomotor activity, and offspring development were assessed. The results demonstrated that LB extract significantly increased pregnancy and live birth rates in naturally aged female mice. It also effectively improved aged animals' locomotor activity. Moreover, LB extract promoted the growth and development of offspring delivered from the aged animals and reduced the offspring's anxiety. During aging, fertility-related hormones gradually decline. However, the decline of anti-Müllerian hormone (AMH) and estradiol (E2) in the serum of aged mice was restored by LB extract supplementation. Immunohistochemical analysis revealed that the levels of oxidation and the inflammatory IL-6 in intra-ovarian cells were reduced by LB extract, while the antioxidant-associated proteins peroxiredoxin 4 (PRDX4) and nuclear factor erythroid 2-related factor 2 (NRF2) were increased. Bioinformatics analysis revealed a decline in egg PRDX4 expression with age across various species. This suggests that the antioxidant function protected by LB extract through PRDX4 may consistently promote fertility enhancement by improving ovarian function across different species. Importantly, LB extract did not induce significant adverse effects on aged female mice and their offspring. These findings highlight the potential of LB as a protective agent against ovarian oxidative stress, which preserves ovarian function and improves fertility rates in naturally senescent females.

mTORC1 - TFEB pathway was involved in sodium arsenite induced lysosomal alteration, oxidative stress and genetic damage in BEAS-2B cells

The mechanistic target of rapamycin (RAPA) complex 1 (mTORC1) - transcription factor EB (TFEB) pathway plays a crucial role in response to nutritional status, energy and environmental stress for maintaining cellular homeostasis. But there is few reports on its role in the toxic effects of arsenic exposure and the related mechanisms. Here, we show that the exposure of bronchial epithelial cells (BEAS-2B) to sodium arsenite promoted the activation of mTORC1 (p-mTORC1) and the inactivation of TFEB (p-TFEB), the number and activity of lysosomes decreased, the content of reduced glutathione (GSH) and superoxide dismutase (SOD) decreased, the content of malondialdehyde (MDA) increased, the DNA and chromosome damage elevated. Further, when mTORC1 was inhibited with RAPA, p-mTORC1 and p-TFEB down-regulated, GSH and SOD increased, MDA decreased, the DNA and chromosome damage reduced significantly, as compared with the control group. Our data revealed for the first time that mTORC1 - TFEB pathway was involved in sodium arsenite induced lysosomal alteration, oxidative stress and genetic damage in BEAS-2B cells, and it may be a potential intervention target for the toxic effects of arsenic.