Nonylphenol (NP) is an ultimate degradation product of nonylphenol polyethoxylates (NPE) that is primarily used in cleaning and industrial processes. Its widespread use has led to the wide existence of NP in various environmental matrices, such as water, sediment, air and soil. NP can be decreased by biodegradation through the action of microorganisms under aerobic or anaerobic conditions. Half-lives of biodegradation ranged from a few days to almost one hundred days. The degradation rate for NP was influenced by temperature, pH and additions of yeast extracts, surfactants, aluminum sulfate, acetate, pyruvate, lactate, manganese dioxide, ferric chloride, sodium chloride, hydrogen peroxide, heavy metals, and phthalic acid esters. Although NP is present at low concentrations in the environment, as an endocrine disruptor the risks of long-term exposure to low concentrations remain largely unknown. This paper reviews the occurrence of NP in the environment and its aerobic and anaerobic biodegradation in natural environments and sewage treatment plants, which is essential for assessing the potential risk associated with low level exposure to NP and other endocrine disruptors.
Purple sweet potato color (PSPC), a naturally occurring anthocyanin, has a powerful antioxidant activity in vitro and in vivo. This study explores whether PSPC has the neuroprotective effect on the aging mouse brain induced by D-galactose (D-gal). The mice administrated with PSPC (100 mg/kg.day, 4 weeks, from 9th week) via oral gavage showed significantly improved behavior performance in the open field and passive avoidance test compared with D-gal-treated mice (500 mg/kg.day, 8 weeks). We further investigate the mechanism involved in neuroprotective effects of PSPC on mouse brain. Interestingly, we found, PSPC decreased the expression level of glial fibrillary acidic protein (GFAP), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), inhibited nuclear translocation of nuclear factor-kappaB (NF-κB), increased the activity of copper/zinc superoxide dismutase (Cu/Zn-SOD) and catalase (CAT), and reduced the content of malondialdehyde (MDA), respectively. Our data suggested that PSPC attenuated D-gal-induced cognitive impairment partly via enhancing the antioxidant and anti-inflammatory capacity.
Adult stem cell identity, plasticity, and homeostasis are precisely orchestrated by lineage-restricted epigenetic and transcriptional regulatory networks. Here, by integrating super-enhancer and chromatin accessibility landscapes, we delineate core transcription regulatory circuitries (CRCs) of limbal stem/progenitor cells (LSCs) and find that RUNX1 and SMAD3 are required for maintenance of corneal epithelial identity and homeostasis. RUNX1 or SMAD3 depletion inhibits PAX6 and induces LSCs to differentiate into epidermal-like epithelial cells. RUNX1, PAX6, and SMAD3 (RPS) interact with each other and synergistically establish a CRC to govern the lineage-specific cis-regulatory atlas. Moreover, RUNX1 shapes LSC chromatin architecture via modulating H3K27ac deposition. Disturbance of RPS cooperation results in cell identity switching and dysfunction of the corneal epithelium, which is strongly linked to various human corneal diseases. Our work highlights CRC TF cooperativity for establishment of stem cell identity and lineage commitment, and provides comprehensive regulatory principles for human stratified epithelial homeostasis and pathogenesis.
METHODS. Twenty-one white rabbits (42 eyes) were randomly divided into three groups. The control group was untreated. The two experimental groups were treated with 0.02% BACcontaining latanoprost once a day combined with unpreserved 0.3% SH or PBS three times daily for 60 days. Schirmer test, fluorescein and rose bengal staining, and conjunctiva impression cytology were performed on days 0, 31, and 61. Apoptosis of conjunctival epithelium was detected by TUNEL assay on day 61. Conjunctival inflammation was evaluated with light microscopy. Cornea and conjunctiva ultrastructure were observed by electron microscopy.
RESULTS.Compared with the control group, the PBS-treated latanoprost group showed increases in fluorescein and rose bengal scores, decreases in Schirmer scores, and goblet cell density (GCD) on days 31 and 61. Increases in inflammatory and apoptotic cells in conjunctiva, and ultrastructural disorders of the cornea and conjunctiva were also observed on day 61. Compared with the PBS-treated latanoprost group, the SH-treated latanoprost group showed decreases in fluorescein and rose bengal scores, and increases in Schirmer scores and GCD on days 31 and 61. Decreases in inflammatory and apoptotic cells in conjunctiva and amelioration of ultrastructural disorders were also observed.CONCLUSIONS. Topical application of SH significantly decreased the ocular surface toxicity induced by BAC-preserved latanoprost. As a vehicle or neutralizing material, SH could be proposed to reduce ocular toxicity and protect the ocular surface in long-term BAK-preserved antiglaucoma medication treatment.
Aim: To investigate the effects of rosiglitazone, a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, on the expression of the phosphatase and tensin homologue deleted on chromosome 10 gene (PTEN) and cell growth in hepatocellular carcinoma cells, as well as the underlying mechanisms of these effects. Methods: RT-PCR and Western blotting analyses were performed to detect transcription and the expression of PTEN in Hep3B cells treated with rosiglitazone. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay was used to evaluate cell growth. Flow cytometry, DNA fragmentation analysis, caspase enzymatic assay, and Hoechst 33258 staining were used to determine cell apoptosis. Furthermore, small interfering RNA was used to suppress PTEN expression. Results: Rosiglitazone increased the expression of PTEN in a doseand time-dependent manner through the PPARγ-dependent signal transduction pathway. PTEN upregulation was concomitant with a decreased level of Akt phosphorylation, subsequently resulting in cell growth inhibition and apoptosis in Hep3B cells. PTEN knockdown dramatically blocked these effects of rosiglitazone. Moreover, the exposure of cells to rosiglitazone activated caspases-9 and -3 during apoptotic proceeding. Conclusion: Thus, upregulation of PTEN is involved in the inhibition of cell growth and the induction of cell apoptosis by rosiglitazone, suggesting that rosiglitazone may be useful in liver cancer therapy via apoptosis.
Aim: Epigallocatechin‐3‐gallate (EGCG) is the major component of green tea polyphenols, whose wide range of biological properties includes anti‐fibrogenic activity. Matrix metalloproteinases (MMP) that participate in extracellular matrix degradation are involved in the development of hepatic fibrosis. The present study investigates whether EGCG inhibits activation of the major gelatinase matrix metalloproteinase‐2 (MMP‐2) in rat hepatic stellate cells (HSC). Methods: The expression of MMP‐2, tissue inhibitors of metalloproteinases‐2 (TIMP‐2), and membrane‐type 1‐MMP (MT1‐MMP) was assessed by RT‐PCR and Western blot analyses. MMP‐2 activity was evaluated by zymography and MT 1‐MMP activity was assessed by an enzymatic assay. HSC migration was measured by a wound healing assay and cell invasion was performed using Transwell cell culture chambers. Results: The expression of MMP‐2 mRNA and protein in HSC was substantially reduced by EGCG treatment. EGCG treatment also reduced con‐canavalin A (ConA)‐induced activation of secreted MMP‐2 and reduced MT1‐MMP activity in a dose‐dependent manner. In addition, EGCG inhibited either HSC migration or invasion. Conclusion: The abilities of EGCG to suppress MMP‐2 activation and HSC invasiveness suggest that EGCG may be useful in the treatment and prevention of hepatic fibrosis.
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