UV-B Filter Octylmethoxycinnamate Alters the Vascular Contractility Patterns in Pregnant Women with Hypothyroidism

Exposure to UV-B filter octylmethoxycinnamate and human health effects: Focus on endocrine disruptor actions

Human skin is the first line of photoprotection against UV radiation. However, despite having its defence mechanisms, the photoprotection that the skin exerts is not enough. To protect human skin, the inclusion of UV filters in the cosmetic industry has grown significantly as a photoprotection strategy. Octylmethoxycinnamate, also designated by octinoxate, or 2-ethylhexyl-4-methoxycinnamate (CAS number: 5466-77-3) is one of the most widely used UV-B filter in the cosmetic industry. The toxic effects of OMC have alarmed the public, but there is still no consensus in the scientific community about its use. This article aims to provide an overview of the UV filters' photoprotection, emphasizing the OMC and the possible negative effects it may have on the public health. Moreover, the current legislation will be addressed. In summary, the recommendations should be rethought to assess their risk-benefit, since the existing literature warns us to endocrine-disrupting effects of OMC. Further studies should be focus on the toxicity of OMC alone, in mixture and should consider its degradation products, to improve the knowledge of its risk assessment as EDC.

Effects associated with exposure to the emerging contaminant octyl-methoxycinnamate (a UV-B filter) in the aquatic environment: a review

Given the increasing concern surrounding ultraviolet (UV) radiation-induced skin damage, there has been a rise in demand for UV filters. Currently, UV-filters are considered emerging contaminants. The extensive production and use of UV filters have led to their widespread release into the aquatic environment. Thus, there is growing concern that UV filters may bioaccumulate and exhibit persistent properties within the environment, raising several safety health concerns. Octyl-methoxycinnamate (OMC) is extensively employed as a UV-B filter in the cosmetic industry. While initially designed to mitigate the adverse photobiological effects attributed to UV radiation, the safety of OMC has been questioned with some studies reporting toxic effects on environment. The aim of this review to provide an overview of the scientific information regarding the most widely used organic UV-filter (OMC), and its effects on biodiversity and aquatic environment.

Disrupting effects of the emerging contaminant octylmethoxycinnamate (OMC) on human umbilical artery relaxation

Cardiovascular diseases (CVD) represent the number one cause of death worldwide. The vascular endothelium may play a role in the pathophysiology of CVD diseases. Octylmethoxycinnamate (OMC) is a UV-B filter (CAS number: 5466-77-3) widely used worldwide in numerous personal care products, including sunscreens, daily creams, and makeup. This UV-B filter is considered an endocrine disruptor. Therefore, this investigation aimed to evaluate the direct effects of OMC in human umbilical arteries (HUAs) with endothelium and the possible mechanisms involved in the response. The results demonstrated that OMC exerts a rapid (non-genomic) and endothelium-dependent arterial relaxant effect on HUAs previously contracted with serotonin (5-HT) and Histamine (His). On the other hand, when HUAs were contracted with potassium chloride (KCl), the relaxing effect was only observed in HUAs without endothelium, and it appeared to be inhibited in HUAs with endothelium. Thus, the vasorelaxant effect of OMC depends on the endothelium and depends on the contractile agent used, suggesting that OMC may act through different signaling pathways. Furthermore, computational modulation studies, corroborated the binding of OMC to all the proteins under investigation (eNOS, COX-2, ET-1, and TxA2), with higher affinity for COX-2. In summary, the vascular effect of OMC may involve activating different pathways, i.e., acting through the NO pathway, COX pathway, or activating the endothelin-1 pathway.

UV-B filter octylmethoxycinnamate-induced vascular endothelial disruption on rat aorta: In silico and in vitro approach

Throughout human life, an extensive and varied range of emerging environmental contaminants, called endocrine disruptors (EDCs), cause adverse health effects, including in the cardiovascular (CV) system. Cardiovascular diseases (CVD) are worryingly one of the leading causes of all mortality and mobility worldwide. The UV-B filter octylmethoxycinnamate (also designated octinoxate, or ethylhexyl methoxycinnamate (CAS number: 5466-77-3)) is an EDC widely present in all personal care products. However, to date, there are no studies evaluating the OMC-induced effects on vasculature using animal models to improve human cardiovascular health. This work analysed the effects of OMC on rat aorta vasculature and explored the modes of action implicated in these effects. Our results indicated that OMC relaxes the rat aorta by endothelium-dependent mechanisms through the signaling pathways of cyclic nucleotides and by endothelium-independent mechanisms involving inhibition of L-Type voltage-operated Ca²⁺ channels (L-Type VOCC). Overall, OMC toxicity on rat aorta may produce hypotension via vasodilation due to excessive NO release and blockade of L-Type VOCC. Moreover, the OMC-induced endothelial dysfunction may also occur by promoting the endothelial release of endothelin-1. Therefore, our findings demonstrate that exposure to OMC alters the reactivity of the rat aorta and highlight that long-term OMC exposure may increase the risk of human CV diseases.

Fetoplacental vasculature as a model to study human cardiovascular endocrine disruption

Increasing evidence has associated the exposure of endocrine-disrupting chemicals (EDCs) with the cardiovascular (CV) system. This exposure is particularly problematic in a sensitive window of development, pregnancy. Pregnancy exposome can affect the overall health of the pregnancy by dramatic changes in vascular physiology and endocrine activity, increasing maternal susceptibility. Moreover, fetoplacental vascular function is generally altered, increasing the risk of developing pregnancy complications (including cardiovascular diseases, CVD) and predisposing the foetus to adverse health risks later in life. Thus, our review summarizes the existing literature on exposures to EDCs during pregnancy and adverse maternal health outcomes, focusing on the human placenta, vein, and umbilical artery associated with pregnancy complications. The purpose of this review is to highlight the role of fetoplacental vasculature as a model for the study of human cardiovascular endocrine disruption. Therefore, we emphasize that the placenta, together with the umbilical arteries and veins, allows a better characterization of the pregnant woman's exposome. Consequently, it contributes to the protection of the mother and foetus against CV disorders in life.

UV-B filter octylmethoxycinnamate impaired the main vasorelaxant mechanism of human umbilical artery

Personal care products (PCPs) are a group of diverse substances widely used daily for health, beauty, and cleanliness. More than 90% of all PCPs contain the UV-B filter octylmethoxycinnamate (OMC) as a protective function, however, their safety has recently been questioned. The purpose of the present work was to understand how the long-term exposure of UV-filter OMC, used daily by pregnant women, disrupts their vascular homeostasis, altering vascular responses of proteins and channels involved in contractile processes. The long-term effects of 24 h of exposure to OMC (1, 10, and 50 μmol/L) were evaluated on contractile responses of human umbilical arteries (HUA) to serotonin and potassium chloride. Since OMC altered vascular homeostasis of arteries, its vascular mode of action was explored in more detail through the analysis of the activity of cGMP and Ca²⁺-channels, two pathways involved in their relaxation and contraction, respectively. Our findings showed that long-term exposure of UV-filter OMC impaired the main vasorelaxant mechanism of HUA, once OMC altered the vasorelaxant response pattern of sodium nitroprusside and nifedipine. Results also showed that long-term exposure to OMC induced a decreased vasorelaxation response on HUA due to an interference with the NO/sGC/cGMP/PKG pathway. Moreover, OMC seems to modulate the L-type Ca²⁺ channels, the BKCa 1.1 α-subunit channels, and the PKG. Overall, since OMC compromises the vascular homeostasis of pregnant women it can be an inductor of pregnancy hypertensive disorders.