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Acute and chronic effects of ultraviolet radiation (UVR) on human health have long been a concern. It is well known that acute UVR causes epidermal hyperplasia, erythema, delayed tanning, pigment darkening, and free-radical formation. Apart from acute effects of UVR, its chronic effects involve immunosuppression, photoaging, exacerbation, photodermatoses, and photocarcinogenesis. To protect skin from harmful effects of UVR, UV filters were developed. But these may cause harmful effects in humans and on the environment; adverse effects of these chemicals have been evaluated for > 20 yr. Studies show that UV filters may lead to endocrine disruption, hepatotoxicity, mutagenicity, and systemic toxicity. Literature on environmental effects of UV filters suggests that they are bioaccumulative, pseudopersistent, and possibly toxic to aquatic ecosystems. The objective of this review is to summarize toxic effects and safety concerns of organic UV filters on human beings and the environment. We focus on UV filters' organic endocrine-disrupting effects by reviewing both in vivo and in vitro studies.

Objective: Exposure to perfluorooctanoic acid (PFOA) is linked to adverse health effects, including cancer and hepatic diseases. PFOA induces reactive oxygen species generation in human hepatic cells, causing oxidative stress and cell death. Resveratrol (RSV) has garnered attention for its protective effects against xenobiotic-induced damage, yet its impact on PFOA-induced oxidative stress and ferroptosis in the liver remains understudied. This study investigates RSV's protective mechanisms against oxidative stress and ferroptosis in HepG2 cells exposed to PFOA. Method: HepG2 cells were cultured in DMEM with 10% FBS and 1% penicillin/streptomycin in a 5% CO2 incubator at 37°C. PFOA was added to the cells at concentrations ranging from 0 to 450 µM and incubated at 37°C for 24 hours. The IC50 was determined to be 457 μM. To examine RSV's protective effects, cells were treated with 60 μM RSV. Following treatment with PFOA, RSV, and the combination of PFOA+RSV, cell lysates were prepared for analysis. Oxidative stress and ferroptosis parameters were measured spectrophotometrically using ELISA. Results: In the PFOA+RSV group, antioxidant capacity increased, and ferroptosis was suppressed compared to the control. Conversely, the PFOA group showed decreased antioxidant capacity, increased oxidant capacity, and induced ferroptosis compared to the control and RSV-treated groups. Conclusion: PFOA exposure heightens oxidative stress and ferroptosis, whereas RSV treatment significantly reduces hepatic oxidative stress and protects against ferroptosis during PFOA exposure. [ABSTRACT FROM AUTHOR]

In this study, we aimed to evaluate possible toxic effects of thimerosal, aluminum and combination of thimerosal and aluminum in SH-SY5Y cells. Inhibitory concentrations were determined by MTT assay; reactive oxygen species (ROS) were determined by a fluorometric kit and antioxidant/oxidant parameters were measured by spectrophotometric kits. Nuclear factor erythroid 2-associated factor 2 (Nrf2), norepinephrine (NE), dopamine transporter (DAT) and dopamine beta β-hydroxylase (DBH) levels were measured by sandwich ELISA kits while 8-hydroxy deoxyguanosine (8-OHdG) and dopamine levels were determined by competitive ELISA kits. Thimerosal (1.15 μM) and aluminum (362 μM) were applied to cells at inhibitory concentrations 20 (IC20s) for 24 h. ROS increased significantly in cells aluminum- and aluminum+thimerosal-treated cells. Glutathione levels decreased in aluminum group while total antioxidant capacity and protein oxidation levels increased significantly in aluminum and aluminum+thimerosal groups. Lipid peroxidation increased significantly in groups treated with aluminum and aluminum+thimerosal. Nrf2 levels and DNA damage were significantly higher in all groups while dopamine levels significantly increased in cells treated with thimerosal and aluminum+thimerosal, DAT levels were found to be higher in all experimental groups compared to the control. These findings showed that both thimerosal and aluminum can change oxidant/antioxidant status, cause DNA damage, alter dopamine and DAT levels. Changes seen in cells treated with combined exposure to aluminum and thimerosal are more pronounced. Special care should be taken while vaccinating sensitive populations and safer alternatives for aluminum and thimerosal should used. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study was to investigate the effects of different degrees of obstruction, and the roles of inflammation, oxidative stress, and hypoxia parameters on bladder function. Methods: Thirty male Sprague–Dawley rats were divided into 3 groups (n = 10 in each group): (i) sham‐operated control; (ii) severe partial bladder outlet obstruction (PBOO); and (iii) moderate PBOO. Severe and moderate PBOO were induced by urethral ligation using 3‐Fr and 4‐Fr catheters, respectively, for 6 weeks. After 6 weeks, the in vitro contractile responses to carbachol, electrical field stimulation, ATP and KCl were measured in bladder strips. In addition, mRNA and protein expression of nuclear factor kappa B (NF‐κB) hypoxia‐inducible factor (HIF) and nuclear factor, erythroid 2‐like 2 (Nrf2) in bladder were determined by real‐time polymerase chain reaction and western blotting. Malondialdehyde (MDA) levels in bladder tissues were also determined. Results: Rats in the severe PBOO group had the highest bladder weight. Detrusor strips from rats in the severe PBOO group exhibited 61%–82% smaller contractile responses to all four stimuli than those from the sham‐operated group. Activity of NF‐κB as an inflammatory marker was increased in the severe PBOO group, whereas HIF‐1α and HIF‐2β protein levels were increased significantly in the moderate PBOO group. A master regulator of oxidative stress, Nrf2 expression was increased in all obstructed rats. MDA levels were higher in the severe PBOO group than in sham‐operated group. Conclusion: The results of the present study reveal the importance of oxidative stress‐induced NF‐κB signaling in bladder dysfunction with severe obstruction. Altered HIF signaling may contribute to the functional impairment after PBOO. Novel and evolving therapies targeting oxidative and/or inflammatory pathways may be a reasonable strategy for the management of lower urinary tract symptoms or benign prostatic hyperplasia. [ABSTRACT FROM AUTHOR]