Daily Archives: 22 April 2024

Selenium diminishes the adverse health impacts of mixtures of environmental pollutants

The groundbreaking research conducted at the University of Cordoba has illuminated the cumulative health risks of environmental pollutants, particularly the toxic amalgamation of metal and pharmaceutical residues that infiltrate our water and food sources. This study has not only underscored the potential mitigating effects of incorporating selenium into the diet but also provided a new perspective on the complex interplay of these dangers.

Daily exposure to potentially harmful external substances is unavoidable in modern life. Metals like arsenic, cadmium, and mercury, alongside pharmaceutical residues such as diclofenac and flumequine, often find their way into our environment in concentrations that, when combined, surpass their individual threat levels due to synergistic interactions. This complex interplay escalates their toxicity, posing a significant health risk.

The magnitude of the impact of environmental pollution on living organisms cannot be overstated. Developing safety regulations that limit human exposure to these pollutants is of utmost importance. However, the issue becomes exponentially more intricate when dealing with pollutant mixtures. Even at doses deemed acceptable for each individual compound, their combined effect can lead to unforeseen and potentially severe consequences.

Aiming to demystify the health implications of these “contaminant cocktails,” a research team from the Biochemistry and Molecular Biology Department at the University of Cordoba embarked on a study. The team, consisting of Nieves Abril, Paula Huertas, María José Prieto, and Juan Jurado, specifically focused on a prevalent environmental mixture that accumulates through the food chain: a concoction of metals and drugs.

The study meticulously explored the interaction between these contaminants through a controlled exposure of mice to the mixture, observing its effects on liver protein expression over two weeks. Professor Nieves Abril elaborated on their method, highlighting their use of shotgun proteomics to identify significant alterations in protein behaviour compared to a control group. This approach unveiled a synergistic damage enhancement when these contaminants were combined, leading to a compromised health state.

Upon analyzing 275 sentinel proteins, the researchers could map out the disrupted metabolic pathways and their detrimental health effects. They noted an overactive defence response, which paradoxically inflicted more harm by continuously triggering antioxidant defences without allowing them to deactivate. This phenomenon resulted in significant oxidative stress, rendering many proteins dysfunctional.

In its search for a solution, the study pointed towards selenium, a mineral commonly found in dietary supplements. A separate group of mice treated with selenium showed a marked improvement in handling the molecular damage inflicted by the pollutants. Selenium, though an oxidant in its own right, fostered a controlled activation of the body’s defensive mechanisms, enhancing its overall resilience against such contaminants.

This research, supported by the Research Support (SCAI) and Experimental Animals (SAEX) services, has expanded our understanding of the threats posed by everyday pollutants and offered a glimmer of hope. Selenium supplementation is a viable method to alleviate the adverse health effects caused by our constant exposure to a mixture of environmental pollutants.

More information: Paula V. Huertas-Abril et al, Proteomic analysis of the hepatic response to a pollutant mixture in mice. The protective action of selenium, Science of The Total Environment. DOI: 10.1016/j.scitotenv.2023.166558

Journal information: Science of The Total Environment Provided by University of Córdoba

Treatment through brain stimulation could enhance the well-being of older adults suffering from depression and anxiety

In a recent study led by the University of Florida, a noninvasive method of brain stimulation showed promise in alleviating symptoms of depression and anxiety among older adults. The study found that those who began with higher levels of symptoms saw the most significant improvements. Notably, for individuals experiencing moderate to severe anxiety linked to stressful situations, the benefits of this treatment were sustained even after a year.

This research, detailed in the Brain Stimulation journal, explored the effectiveness of transcranial direct current stimulation (tDCS) as a viable, non-pharmacological therapy for depression and anxiety, which impacts approximately one in four older adults. Adam Woods, Ph.D., a senior author of the study, highlighted the importance of such noninvasive treatments. These options are especially crucial for individuals who do not respond to traditional medication, cannot access or engage in intensive treatment programs, or face other barriers.

The University of Florida study observed the treatment’s efficacy not only in participants with clinically diagnosable depression and anxiety but also in those with subclinical levels of these conditions. Subclinical symptoms, which may not fulfil the criteria for a formal diagnosis, can nonetheless contribute to cognitive decline in older adults.

The procedure involves a mild electrical current passed through electrodes on the scalp, targeting the prefrontal cortex— a brain area involved in cognitive and emotional regulation. The study, part of the National Institute on Aging-funded initiative, is the largest and involved nearly 400 older adults across the University of Florida and the University of Arizona sites. Participants were divided into groups receiving 12 weeks of tDCS alongside cognitive or cognitive training with a placebo tDCS.

Beyond improvements in depression and anxiety, the study collected comprehensive data, including cognitive function, brain imaging, and self-reported psychological symptoms. Results showed that tDCS recipients experienced significant enhancements in managing mild depression and state anxiety when compared to those who received placebo treatment.

Hanna Hausman, the study’s lead author, emphasized the novelty and significance of finding such positive outcomes in older adults without significant psychiatric histories, especially on a large scale. She suggested that these findings could pave the way for future research, including a phase 3 clinical trial to investigate further the effects of tDCS and cognitive training on anxiety in older adults.

Internationally, tDCS has already been recognized for its potential; for instance, the Korea Food and Drug Administration has approved it for at-home depression treatment. With additional research, this treatment could gain approval in the U.S., offering a cost-effective, portable, and user-friendly option for managing mental health. Hausman noted the potential for tDCS to be integrated with existing therapies or used independently, enhancing accessibility for those facing challenges in accessing conventional clinical care.

More information: Hanna K. Hausman et al, tDCS reduces depression and state anxiety symptoms in older adults from the augmenting cognitive training in older adults study (ACT), Brain Stimulation. DOI: 10.1016/j.brs.2024.02.021

Journal information: Brain Stimulation Provided by University of Florida