PURPOSE: To determine the possible effects of chronic exposure of low dose benzalkonium chloride (BAK) on trabecular meshwork cells, and to characterize the pathways involved in the effects. METHODS: Trabecular meshwork cells were treated with 0.0005%, 0.00075%, 0.001%, and 0.0025% BAK for 10 minutes; then, the cells were transferred to a new medium for 24 hours. This process was repeated three times. Cell survival was assessed using the MTT assay to determine the non-apoptotic BAK concentration. Senescence-associated (SA)-β-gal staining was performed to compare quantitatively the cellular senescence of BAK-treated cells with the control group. Cells treated with BAK were analyzed by western blot to determine whether the expressions of cell cycle regulators were affected. RESULTS: Two concentrations (0.0005% and 0.00075%) showed persistent cell viability and were chosen for further experiments. After SA-β-gal staining, cells treated with 0.0005% and 0.00075% BAK showed 28% (± 2.08), 37% (± 2.08) increases in cellular senescence expression, respectively, when compared with control cells (p < 0.05). To identify the molecular pathways involved in cell cycle arrest via BAK, western blot analysis was performed on trabecular meshwork cells, resulting in decreased expressions of cyclin E/CDK2, and increased expressions of the upper stream control molecules, p53 and p21. CONCLUSIONS: Chronic exposure to low dose BAK accelerated cell senescence through cell cycle arrest. Because senescent cells of the trabecular meshwork can inhibit its outflow pathway function and ultimately worsen the glaucomatous process, long-term usage of topical glaucoma medications containing BAK should be conducted with caution.
Aging ; Benzalkonium Compounds ; Blotting, Western ; Cell Aging ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Survival ; Cyclins ; Glaucoma ; Rivers ; Trabecular Meshwork

This study compared the effect of preservative-containing (PC) and preservative-free (PF) prostaglandin analogue (PGA) formulations on the ocular surface, especially on the meibomian gland (MG) in patients with open-angle glaucoma (OAG). This is a retrospective study of treatment-naïve patients with OAG (n=80) and healthy controls (n=40). OAG patients were randomized into groups using either PC-PGA or PF-PGA for 12 months. All participants underwent ocular surface and MG examinations including their meibum score, meiboscore, and lid margin abnormality score (LAS). Eighty OAG patients were randomized into two groups (n=42 in PC, n=38 in PF). All PGA and control groups showed similar ocular surface and MG parameters at the baseline. Both PC- and PF-PGA groups showed increased meibum scores, meiboscores, and LASs at 12 months compared to the baseline (all p<0.05). At the 12-months visit, PC-PGA group showed severe OSDI, shorter TBUT, greater OSS, and worse MG parameters than those of the other two groups (all p<0.05). In addition, PF-PGA group showed worse meiboscores, meibum scores, and severe OSS scores than those of the control group (all p<0.05). Both PC and PF formulations can cause damage to the MG in patients using PGA. However, PC formulations induced more ocular discomfort, poorer ocular surface, and more severe MG loss compared to PF formulations. Therefore, it would be advisable to use PF formulations in patients with a preexisting or concomitant ocular surface disease or MGD.
Benzalkonium Compounds ; Glaucoma ; Glaucoma, Open-Angle ; Humans ; Meibomian Glands ; Preservatives, Pharmaceutical ; Prostaglandins, Synthetic ; Retrospective Studies

Benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea are commonly used preservatives in cosmetics. Recent reports suggested that these compounds may have cellular and systemic toxicity in high concentration. In addition, diazolidinyl urea and imidazolidinyl urea are known formaldehyde (FA) releasers, raising concerns for these cosmetic preservatives. In this study, we investigated the effects of benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea on ROS-dependent apoptosis of rat neural progenitor cells (NPCs) in vitro. Cells were isolated and cultured from embryonic day 14 rat cortices. Cultured cells were treated with 1–1,000 nM benzalkonium chloride, and 1–50 μM diazolidinyl urea or imidazolidinyl urea at various time points to measure the reactive oxygen species (ROS). PI staining, MTT assay, and live-cell imaging were used for cell viability measurements. Western blot was carried out for cleaved caspase-3 and cleaved caspase-8 as apoptotic protein markers. In rat NPCs, ROS production and cleaved caspase-8 expression were increased while the cell viability was decreased in high concentrations of these substances. These results suggest that several cosmetic preservatives at high concentrations can induce neural toxicity in rat brains through ROS induction and apoptosis.
Animals ; Apoptosis* ; Benzalkonium Compounds ; Blotting, Western ; Brain ; Caspase 3 ; Caspase 8 ; Cell Survival ; Cells, Cultured ; Formaldehyde ; In Vitro Techniques ; Rats* ; Reactive Oxygen Species ; Stem Cells* ; Urea

No abstract available.
Benzalkonium Compounds* ; Dermatitis, Contact*

PURPOSE: The changes in tear film lipid layer thickness (LLT) after artificial tears application using LipiView®II interferometer were assessed. METHODS: We performed a prospective study of patients with dry eye disease. All subjects underwent measurement of tear film break-up time, Schirmer test, ocular surface staining, meibomian gland evaluation, and subjective score assessment using the Ocular Surface Disease Index. All subjects were randomly assigned to 1 of 3 groups using table of random numbers (group 1, sodium hyaluronate [HA] 0.1% eye drops without preservatives; group 2, HA 0.3% eye drops without preservatives and group 3, HA 0.1% with benzalkonium chloride 0.003%). LLT was measured before, immediately after and 1 hr, 3 hrs, and 6 hrs after artificial tears application. Additionally, the patients were divided into 2 subgroups depending on the presence of meibomian gland dysfunction (MGD) and further evaluated. RESULTS: Significant change in LLT was observed at 3 hrs after artificial tears instillation. LLT in groups 1 and 2 showed significant changes over time (p < 0.01 and p < 0.01, respectively). However, LLT in group 3 showed no change. LLT was unchanged in patients without MGD. Conversely, in MGD patients, a significant difference in LLT between groups 1 and 2 was observed immediately after and 1 hr and 3 hrs after instillation of artificial tears (p = 0.04, p < 0.01 and p = 0.02, respectively) but not at 6 hrs. However, no significant difference in LLT between groups 1 and 3 was observed in MGD patients. CONCLUSIONS: LLT after instillation of artificial tears measured using LipiView®II interferometer was affected by artificial tear concentration and presence of preservatives. Additionally, the presence of MGD can impact the pattern of LLT changes induced by artificial tear instillation. Therefore, LLT measurements using LipiView®II interferometer require at least a 6-hrs interval after use of eye drops, especially for patients with MGD or using artificial tears with preservatives.
Benzalkonium Compounds ; Eye Diseases ; Humans ; Hyaluronic Acid ; Lubricant Eye Drops ; Meibomian Glands ; Ophthalmic Solutions ; Prospective Studies ; Tears*

Benzalkonium chloride (BAC) is a caustic agent which is used in farms, homes and hospitals for cleaning skin and wounds as an antiseptic solution. It may lead to digestive system injuries in case of ingestion. We present a two-days-old newborn case which was carried to the emergency unit with complaints of poor breastfeeding, uneasiness and crying for 4-6 hours. Her mom confessed that she had given a spoon of 10% BAC solution for her cough. Initial laboratory tests were in normal ranges. A gastroscopy performed in the second hour of her admission revealed an hyperemic and edematous mucosa in the middle third of esophagus and a circumferential ulceration followed in the distal portion. Hereupon, a conservative treatment for 10 days was administered and the control gastroscopy demonstrated that the damage was almost totally improved. She was the youngest case with this etiology and successfully treated with conservative approach.
Agriculture ; Benzalkonium Compounds* ; Breast Feeding ; Cough ; Crying ; Digestive System ; Eating ; Emergency Service, Hospital ; Esophagitis* ; Esophagus ; Gastroscopy ; Humans ; Infant, Newborn* ; Mucous Membrane ; Reference Values ; Skin ; Ulcer ; Wounds and Injuries

PURPOSE: To investigate the effects of benzalkonium chloride (BAC), mitomycin C (MMC) and dexamethasone (DEX) on cellular stress in cultured human trabecular meshwork cell (HTMC) monolayers. METHODS: HTMCs were cultured in the inner Transwell chamber until confluence and then were exposed to BAC, MMC or DEX for 6 hours. The carboxyfluorescein permeability through the HTMC monolayer was measured using a spectrofluorometer at 532 nm after 2 hours in the outer chamber. The 3-[4, 5 -dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay was used to evaluate cellular viabilities. RESULTS: The carboxyfluorescein permeability through the HTMC monolayer increased and cell survival decreased with 0.002% BAC (p < 0.05). Increased permeability without decreasing cell survival occurred with 0.05 microg/mL MMC. No effect on the permeability or cell survival was observed at 0.1 or 1.0 microm DEX (p > 0.05). CONCLUSIONS: BAC and MMC induced cellular toxicity and stress at lower concentrations but did not affect survival of cultured HTMCs.
Benzalkonium Compounds* ; Cell Survival ; Dexamethasone* ; Humans ; Mitomycin* ; Permeability ; Trabecular Meshwork*

PURPOSE: To investigate the effects of bimatoprost on the permeability of cultured human trabecular meshwork cells (HTMC) monolayer. METHODS: HTMCs were cultured until confluency in the inner Transwell chamber and then exposed to benzalkonium chloride, brimonidine, latanoprost or bimatoprost for 1 week. Carboxyfluorescein permeability through the HTMC monolayer was measured using a spectrofluorometer after 2 hours in the outer chamber. Cellular viability was assessed using the MTT assay. RESULTS: Each drug diluted at 1/1000X did not affect the cellular survival (p > 0.05). Brimonidine, latanoprost and bimatoprost did not affect the carboxyfluorescein permeability through the HTMC monolayer (p > 0.05). The carboxyfluorescein permeability was not different between latanoptost and bimatoprost after 1 week of exposure (p > 0.05). CONCLUSIONS: Bimatoprost, a drug known to increase trabecular outflow, does not affect the carboxyfluorescein permeability through the HTMC monolayer. Thus, the effect on the trabecular outflow of bimatoprost may not be significant.
Benzalkonium Compounds ; Humans ; Permeability* ; Trabecular Meshwork* ; Bimatoprost ; Brimonidine Tartrate

BACKGROUNDLong-term use of benzalkonium chloride (BAC)-preserved drugs is often associated with ocular surface toxicity. Ocular surface symptoms had a substantial impact on the glaucoma patients' quality of life and compliance. This study aimed to investigate the effects of sodium hyaluronate (SH) on ocular surface toxicity induced by BAC-preserved anti-glaucoma medications treatment.

METHODSFifty-eight patients (101 eyes), who received topical BAC-preserved anti-glaucoma medications treatment and met the severe dry eye criteria, were included in the analysis. All patients were maintained the original topical anti-glaucoma treatment. In the SH-treated group (56 eyes), unpreserved 0.3% SH eye drops were administered with 3 times daily for 90 days. In the control group (55 eyes), phosphate-buffered saline were administered with 3 times daily for 90 days. Ocular Surface Disease Index (OSDI) questionnaire, break-up time (BUT) test, corneal fluorescein staining, corneal and conjunctival rose Bengal staining, Schirmer test, and conjunctiva impression cytology were performed sequentially on days 0 and 91.

RESULTSCompared with the control group, SH-treated group showed decrease in OSDI scores (Kruskal-Wallis test: H = 38.668, P < 0.001), fluorescein and rose Bengal scores (Wilcoxon signed-ranks test: z = -3.843, P < 0.001, and z = -3.508, P < 0.001, respectively), increase in tear film BUT (t-test: t = -10.994, P < 0.001) and aqueous tear production (t-test: t = -10.328, P < 0.001) on day 91. The goblet cell density was increased (t-test: t = -9.981, P < 0.001), and the morphology of the conjunctival epithelium were also improved after SH treatment.

CONCLUSIONSSH significantly improved both symptoms and signs of ocular surface damage in patients with BAC-preserved anti-glaucoma medications treatment. SH could be proposed as a new attempt to reduce ocular surface toxicity, and alleviate symptoms of ocular surface damage in BAC-preserved anti-glaucoma medications treatment.

Adolescent ; Adult ; Aged ; Benzalkonium Compounds ; adverse effects ; Dry Eye Syndromes ; chemically induced ; prevention & control ; Eye ; drug effects ; Eye Injuries ; chemically induced ; prevention & control ; Female ; Glaucoma ; drug therapy ; Humans ; Hyaluronic Acid ; therapeutic use ; Male ; Middle Aged ; Young Adult

Ketotifen fumarate (KF) is a widely used drug for prophylaxis and the treatment of allergic conditions. Adverse cutaneous reactions to KF are rare except for dryness of the skin and mouth. To the best of our knowledge, no case of allergic contact dermatitis to ketotifen fumarate has yet been reported in the Korean literature. A 60-year-old woman presented with pruritic erythematous patches on the periorbital area. She had used KF eyedrops (Ketoftil ophthalmic solution(R)) for itchy eyes after cataract surgery, and the periorbital lesions developed four weeks later. The KF eyedrops contained not only KF (0.69 mg/ml) but also benzalkonium chloride (0.1 mg/ml). We performed patch tests with the Korean standard patch test series:KF (0.69 mg/ml, 0.069 mg/ml and 0.0069 mg/ml in aqueous solution), and benzalkonium chloride (0.1% in petrolatum). These patch tests showed weak positive reaction to KF (0.69 mg/ml and 0.069 mg/ml) and nickel sulfate, and a negative reaction to benzalkonium chloride. The skin lesions improved rapidly after stopping the eyedrops and applying a topical steroid. We herein report on a rare case of allergic contact dermatitis to ketotifen fumarate eyedrops.
Benzalkonium Compounds ; Cataract ; Dermatitis, Allergic Contact ; Eye ; Female ; Humans ; Ketotifen ; Middle Aged ; Mouth ; Nickel ; Ophthalmic Solutions ; Patch Tests ; Skin