Wang J, Liu Y, Kam WR, Li Y, Sullivan DA.
Toxicity of the cosmetic preservatives parabens, phenoxyethanol and chlorphenesin on human meibomian gland epithelial cells. Exp Eye Res 2020;196:108057.
AbstractRecently, we discovered that the cosmetic preservatives, benzalkonium chloride and formaldehyde, are especially toxic to human meibomian gland epithelial cells (HMGECs). Exposure to these agents, at concentrations approved for human use, leads within hours to cellular atrophy and death. We hypothesize that these effects are not unique, and that other cosmetic preservatives also exert adverse effects on HMGECs. Such compounds include parabens, phenoxyethanol and chlorphenesin, which have been reported to be toxic to corneal and conjunctival epithelial cells, the liver and kidney, as well as to irritate the eye. To test our hypothesis, we examined the influence of parabens, phenoxyethanol and chlorphenesin on the morphology, signaling, survival, proliferation and lipid expression of immortalized (I) HMGECs. These cells were cultured under proliferating or differentiating conditions with varying concentrations of methylparaben, ethylparaben, phenoxyethanol and chlorphenesin for up to 5 days. We monitored the signaling ability, appearance, number and neutral lipid content of the IHMGECs, as well as their lysosome accumulation. Our findings show that a 30-min exposure of IHMGECs to these preservatives results in a significant reduction in the activity of the Akt pathway. This effect is dose-dependent and occurs at concentrations equal to (chlorphenesin) and less than (all others) those dosages approved for human use. Further, a 24-h treatment of the IHMGECs with concentrations of methylparaben, ethylparaben, phenoxyethanol and chlorphenesin close to, or at, the approved human dose induces cellular atrophy and death. At all concentrations tested, no preservative stimulated IHMGEC proliferation. Of particular interest, it was not possible to evaluate the influence of these preservatives, at close to human approved dosages, on IHMGEC differentiation, because the cells did not survive the treatment. In summary, our results support our hypothesis and show that methylparaben, ethylparaben, phenoxyethanol and chlorphenesin are toxic to IHMGECs.
Wolkow N, Jakobiec FA, Gragoudas ES.
LONG-TERM OBSERVATION OF MULTIFOCAL METASTATIC INTRAOCULAR CARCINOID WITH ACQUIRED IRIS HETEROCHROMIA. Retin Cases Brief Rep 2020;14(3):265-267.
AbstractBACKGROUND/PURPOSE: To report a unique case of a pulmonary carcinoid tumor unilaterally metastatic to the iris and ciliary body and bilaterally to the choroid that was conservatively followed. METHODS: A 46-year-old woman presented with bilateral choroidal lesions and a left iris tumor. Ultrasound biomicroscopy disclosed a ciliary body component. A diagnosis of metastatic carcinoid tumor was made based on the clinical features. Rather than an excision, photodynamic therapy, or radiation treatment, as has been reported in all previous cases of carcinoid tumor metastatic to the iris, the patient was observed. RESULTS: Excellent vision was maintained for 8 years. The iris tumor gradually enlarged, but the choroidal lesions remained unchanged. The iris with the carcinoid tumor gradually acquired a brown pigmentation; this is the first reported case of acquired iris heterochromia in the setting of carcinoid tumor. CONCLUSION: We conclude, in cases of metastatic carcinoid in which visual acuity is excellent and the patient is asymptomatic, that observation of the ocular lesions is an acceptable course of action. The iris heterochromia is believed to have been caused by secretory factors produced by the tumor.