Toxicological evaluation of isopropylparaben and isobutylparaben mixture in Sprague-Dawley rats following 28 days of dermal exposure.

The alkyl esters of p-hydroxybenzoic acid (Parabens) have been of concern due to their probable endocrine disrupting property especially in baby consumer products. The safety of parabens for use as a preservative in cosmetics has come into controversy, and thus consumer demand for paraben-free products is ever increasing. Thus, more comprehensive studies are needed to conclusively determine the safety of the multiple prolonged exposure to parabens with cosmetic ingredients. This study was conducted to investigate the potential repeated 28 days dermal toxicity (50, 100, 300, or 600 mg/kg bw/day) of isopropylparaben (IPP), isobutylparaben (IBP), or the mixture of IPP and IBP in rats. There were no significant changes in body and organ weights in any group. However, histopathological examinations showed that weak or moderate skin damages were observed in female rats by macroscopic and microscopic evaluations. In female rats, no observed adverse effect levels (NOAELs) of IPP with no skin lesion and IBP for skin hyperkeratosis, were estimated to be 600 mg/kg bw/day, and 50 mg/kg bw/day, respectively. With regard skin hyperkeratosis, the lowest observed adverse effect level (LOAEL) of the mixture of IPP and IBP was estimated to be 50 mg/kg bw/day. Analysis of six serum hormones (estrogen, testosterone, insulin, T3, TSH, or FSH) in animals showed that only FSH was dose-dependently decreased in the mixture groups of 100 mg/kg bw/day or higher. These data suggest that the mixture of IPP and IBP showed a synergistic dermal toxicity in rats and should be considered for future use in consumer products.

Treatment of ocular surface squamous neoplasia with topical Aloe vera drops.

PURPOSE: To report a case of ocular surface squamous neoplasia (OSSN) that resolved with topical Aloe vera eye drop treatment. METHODS: A 64-year-old Hispanic woman with a lesion typical for OSSN in her left eye was followed up with multiple clinical examinations and ocular surface photographs to document changes over time with A. vera-based topical treatment. RESULTS: The patient refused biopsy of her lesion and traditional treatments and, instead, initiated using A. vera eye drops 3 times daily. At follow-up visits, the lesion was noted to regress until it finally resolved 3 months after commencing treatment. No additional topical medications were used, and she has remained tumor free for 6 years. CONCLUSIONS: Ongoing research is warranted because A. vera may represent a new therapeutic class of medications for OSSN treatment.

Oil palm phenolics confer neuroprotective effects involving cognitive and motor functions in mice.

OBJECTIVES: Phenolics are important phytochemicals which have positive effects on chronic diseases, including neurodegenerative ailments. The oil palm (Elaeis guineensis) is a rich source of water-soluble phenolics. This study was carried out to discover the effects of administering oil palm phenolics (OPP) to mice, with the aim of identifying whether these compounds possess significant neuroprotective properties. METHODS: OPP was given to BALB/c mice on a normal diet as fluids for 6 weeks while the controls were given distilled water. These animals were tested in a water maze and on a rotarod weekly to assess the effects of OPP on cognitive and motor functions, respectively. Using Illumina microarrays, we further explored the brain gene expression changes caused by OPP in order to determine the molecular mechanisms involved. Real-time quantitative reverse transcription-polymerase chain reaction experiments were then carried out to validate the microarray data. RESULTS: We found that mice given OPP showed better cognitive function and spatial learning when tested in a water maze, and their performance also improved when tested on a rotarod, possibly due to better motor function and balance. Microarray gene expression analysis showed that these compounds up-regulated genes involved in brain development and activity, such as those under the regulation of the brain-derived neurotrophic factor. OPP also down-regulated genes involved in inflammation. DISCUSSION: These results suggest that the improvement of mouse cognitive and motor functions by OPP is caused by the neuroprotective and anti-inflammatory effects of the extract.

Retinal vascular occlusion after vitrectomy with retrobulbar anesthesia-observational case series and survey of literature.

BACKGROUND: Severe postoperative loss of vision has been occasionally reported as a rare complication of retrobulbar anesthesia, and several possible causes have been proposed in the literature. In this work, our own and other investigators' experiences with these complications are surveyed with a view to identifying its pathophysiology. PATIENTS: This observational case series refers to six patients who presented during a 3-month period with occlusion of either the central artery itself (n = 3) or a branch thereof (n = 3) 2-14 days after uneventful vitreoretinal surgery following retrobulbar anesthesia with a commercial preparation of mepivacaine (1% Scandicain®, Astra Chemicals, Sweden) containing methyl- and propyl parahydroxybenzoate as preservatives. RESULTS: Three of the patients carried risk factors, which were medically controlled. In three individuals, vasoocclusion was observed after a second vitreoretinal intervention, which was performed 3-12 months after uneventful primary surgery. Good visual recovery was observed in only one instance. CONCLUSIONS: In patients who were anesthetized with preservative-free mepivacaine, no vasoocclusion occurred. In individuals who were anesthetized with mepivacaine containing the preservatives methyl- and propyl parahydroxybenzoate, a tenfold increase in the incidence of eyes requiring re-operation was documented, with a 2- to 14-day lapse in the onset of vasoocclusion. These findings reveal a possible implication of preservatives contained in the local anesthetic solution for the vasoocclusive events. Due to this potential hazard, the use of preservative-free preparations of local anesthesia in ocular surgery is emphasized in order to prevent this sight-threatening complication.

Effect of antioxidant mixtures on growth and ochratoxin a production of Aspergillus section Nigri species under different water activity conditions on peanut meal extract agar.

The effect of mixtures of antioxidants butylated hydroxyanisol (BHA) and propyl paraben (PP) on lag phase, growth rate and ochratoxin A (OTA) production by four Aspergillus section Nigri strains was evaluated on peanut meal extract agar (PMEA) under different water activities (a(w)). The antioxidant mixtures used were: BHA + PP (mM), M1 (0.5 + 0.5), M2 (1.0 + 0.5), M3 (2.5 + 0.5), M4 (0.5 + 1.0), M5 (1.0 + 1.0), M6 (2.5 + 1.0), M7 (5.0 + 2.5) and M8 (10 + 2.5). The mixture M8 completely suppressed mycelial growth for all strains. A significant stimulation in OTA production was observed with mixtures M1 to M5 mainly at the highest a(w); whereas M6, M7 and M8 completely inhibited OTA production in all strains assayed; except M6 in A. carbonarius strain (RCP G). These results could enable a future intervention strategy to minimize OTA contamination.

Ameliorative effects of ginger extract on paraben-induced lipid peroxidation in the liver of mice.

We have evaluated the ameliorative effect of ginger extract on paraben (p-hydroxybenzoic acid)-induced lipid peroxidation in the liver of mice. Adult female albino mice were orally administered with 2.25 or 4.50 mg of paraben in 0.2 mL olive/animal/day (67.5 and 135 mg/kg of body weight) for 30 days. The results revealed significantly higher (p < or = 0.05) lipid peroxidation in the liver of paraben-treated mice than that of controls. As compared with the controls, the levels of non-enzymatic antioxidants: glutathione and ascorbic acid, as well as the enzymatic antioxidants: superoxide dismutase, glutathione peroxidase and catalase were significantly (p < or = 0.05) lowered in the liver of paraben-treated mice. Oral administration of aqueous extract of Zinziber officinale (3 mg/animal/day) along with paraben for 30 days (Groups 6 and 7) caused significant (p < or = 0.05) amelioration in paraben-induced lipid peroxidation and increased significantly (p < or = 0.05) the activities of enzymatic (superoxide dismutase, glutathione peroxidase, catalase) and contents of non-enzymatic (glutathione and ascorbic acid) antioxidants in the liver of mice, as compared with those given paraben alone (Groups 4, 5). Thus, oral administration of aqueous extract of Zinziber officinale along with paraben significantly (p < or = 0.05) ameliorates paraben-induced lipid peroxidation in the liver of mice.

Antioxidative effect of rhizome of Zinziber officinale on paraben induced lipid peroxidation: an in vitro study.

Antioxidative effect of aqueous extract of rhizome of Ginger (Zinziber officinale) was examined on p-hydroxybenzoic acid (paraben) induced lipid peroxidation. Addition of paraben (25-150 microg/mL) to liver and kidney homogenates significantly increases H2O2 induced lipid peroxidation in vitro. Effect was dose dependent up to 100 microg/mL concentration. An addition of aqueous extract of ginger significantly reduced paraben (100 microg/mL) induced lipid peroxidation in liver and kidney homogenates. The effect was concentration dependent.

Ginger extract ameliorates paraben induced biochemical changes in liver and kidney of mice.

The present investigation was undertaken to evaluate the effect of paraben (p-hydroxybenzoic acid) on acidic, basic, and neutral proteins content, as well as carbohydrate and cholesterol contents in liver and kidney of mice. Adult female albino mice were orally administrated with 2.25 and 4.5 mg of paraben in 0.2 mL of olive/animal/day for thirty days. The results revealed dose dependent, significant reduction in acidic, basic, and neutral protein, carbohydrate contents and an increase in cholesterol content of the investigated liver and kidney. Oral administration of aqueous extract of Zinziber officinale (3 mg/animal/day) along with paraben for thirty days caused significant amelioration in all the protein types, carbohydrate and cholesterol of liver and kidney.

Effects of butylparaben on the male reproductive system in rats.

Parabens are a group of compounds widely used as preservatives in foodstuffs, cosmetics, toiletries and pharmaceuticals. These compounds are known to exert a weak estrogenic activity, with butylparaben showing the most potent activity among methyl-, ethyl- and propyl esters in in vitro recombinant yeast assay and in in vivo uterotrophic assay. To account for potential reproductive effects in male animals, butylparaben was administered to 3-week-old Wistar rats divided in groups of eight subjects, at doses of 0.00%, 0.01%, 0.10% and 1.00% with the animal's diet. After 8 weeks, the rats were killed by decapitation and the weights of the testes, epididymides, prostates, seminal vesicles and preputial glands were recorded. The absolute and relative weights of epididymides were decreased in a dose-dependent manner and the decrease was statistically significant at 0.10% and above. The cauda epididymal sperm reserve of all treated groups was significantly decreased. The sperm count of the group receiving the highest dose was 58.2% of control values. The daily sperm production (DSP) in the testis was also significantly lower in all treated groups when compared to controls. Serum testosterone concentration was lowered dose-dependently and was significant at 0.1% or more. The daily intake of butylparaben that caused these disruptions is similar to the lower level of acceptable daily intake (ADI) for parabens in the European Community (EC) and in Japan. The results of the present experiments show for the first time that exposure of a postweaning mammal to butylparaben had an adverse effect on the secretion of testosterone and in the functions of the male reproductive system.