[Show abstract][Hide abstract] ABSTRACT: Inhibition of stearoyl-CoA desaturase 1 (SCD1) has been found to effectively suppress tumor cell proliferation and induce apoptosis in numerous neoplastic lesions. However, mechanism underlying SCD1-mediated anti-tumor effect has maintained unclear. Herein, we reported endo-lipid messenger ceramides played a critical role in tumor fate modulated by SCD1 inhibition. In vitro study in colorectal cancer cells demonstrated inhibition of SCD1 activity promoted apoptosis attributed to mitochondria dysfunctions, upregulation of reaction oxygen species (ROS), alteration of mitochondrial transmembrane potential and translocation of mitochondrial protein cytochrome C. While these effects were mediated by intracellular ceramide signals through induction of ceramide biosynthesis, rather than exclusive SFA accumulation. In vivo study in xenograft colorectal cancer mice showed pharmacologic administration of SCD1 inhibitor A939 significantly delayed tumor growth, which was reversed by L-cycloserine, an inhibitor of ceramide biosynthesis. These results depicted the cross-talk of SCD1-mediated lipid pathway and endo-ceramide biosynthesis pathway, indicating roles of ceramide signals in SCD1-mediated anti-tumor property.
[Show abstract][Hide abstract] ABSTRACT: Purpose:
Inflammation and squamous metaplasia is a common pathological process that occurs in many ocular surface diseases such as dry eye, Stevens-Johnson syndrome, mucous membrane pemphigoid, and chemical/thermal burns. At present, there is no ideal medicinal treatment for this abnormality. We report herein on an ex vivo conjunctival inflammation and squamous metaplasia model by culturing human conjunctival tissues at an air-liquid interface for up to 8 days to study the effects of minocycline on inflammation and squamous metaplasia.
The levels of inflammatory mediators including interleukin-1β, tumor necrosis factor-α, and metalloproteinase-9 in the cultured human conjunctival tissues were determined by enzyme-linked immuno-sorbent assay and real-time polymerase chain reaction. The total and phosphorylated nuclear factor-κB were detected by western blot. Differentiation markers K10, MUC5AC, and Pax6 and proliferation markers Ki67, p63, and K14 were determined by immunofluorescence or immunohistochemical staining.
The results indicated that minocycline inhibited inflammation, decreased the expression of interleukin-1β, tumor necrosis factor-α, and metalloproteinase -9, and squamous metaplasia features such as hyperproliferation and abnormal epidermal differentiation of conjunctival epithelium.
These findings highlight the possibility that minocycline could be used to treat dry eye and other ocular surface diseases exhibiting epithelial cell inflammation and squamous metaplasia.
[Show abstract][Hide abstract] ABSTRACT: Meibomian gland dysfunction is the most frequent cause of evaporative dry eye, yet its underlying pathophysiology is unknown. To gain insight into this pathophysiology, we characterized the time-dependent tear film and ocular surface changes occurring in X-linked anhidrotic-hypohidrotic ectodermal dysplasia mice (Tabby), which lack the meibomian gland. These mice sequentially developed corneal epithelial defects, central corneal stromal edema, neovascularization, and pannus 8 to 16 weeks after birth. Aqueous tear secretion was normal, whereas tear break-up time and ex vivo tear evaporation times were all shortened. Corneal epithelial microvilli were less numerous, conjunctival goblet cell density was unaffected, and MUC5AC and MUC5B gene expression was increased. Markers of squamous metaplasia (cytokeratin 10 and small proline-rich protein 1B) were noticed in the corneal epithelium of Tabby mice as early as the fourth week. Taken together, the Tabby mouse is a relevant meibomian gland dysfunction-related dry eye model that may lead to a better understanding of how meibomian glands are related to ocular surface health. This model may also help with discovering novel drug options for treating evaporative dry eye.
No preview · Article · Nov 2015 · American Journal Of Pathology
[Show abstract][Hide abstract] ABSTRACT: Myopia incidence in China is rapidly becoming a very serious sight compromising problem in a large segment of the general population. Therefore, delineating the underlying mechanisms leading to myopia will markedly lessen the likelihood of other sight compromising complications. In this regard, there is some evidence that patients afflicted with familial adenomatous polyposis (FAP), havean adenomatous polyposis coli (APC) mutation and a higher incidence of myopia. To clarify this possible association, we determined whether the changes in pertinent biometric and biochemical parameters underlying postnatal refractive error development in APCMin mice are relevant for gaining insight into the pathogenesis of this disease in humans. The refraction and biometrics in APCMin mice and age-matched wild-type (WT) littermates between postnatal days P28 and P84 were examined with eccentric infrared photorefraction (EIR) and customized optical coherence tomography (OCT). Compared with WT littermates, the APCMin mutated mice developed myopia (average -4.64 D) on P84 which was associated with increased vitreous chamber depth (VCD). Furthermore, retinal and scleral changes appear in these mice along with: 1) axial length shortening; 2) increased retinal cell proliferation; 3) and decreased tyrosine hydroxylase (TH) expression, the rate-limiting enzyme of DA synthesis. Scleral collagen fibril diameters became heterogeneous and irregularly organized in the APCMin mice. Western blot analysis showed that scleral alpha-1 type I collagen (col1α1) expression also decreased whereas MMP2 and MMP9 mRNA expression was invariant. These results indicate that defective APC gene function promotes refractive error development. By characterizing in APCMin mice ocular developmental changes, this approach provides novel insight into underlying pathophysiological mechanisms contributing to human myopia development.
[Show abstract][Hide abstract] ABSTRACT: In patients with primary canaliculitis, conservative medical therapy is associated with a high recurrence rate. Surgical treatments carry a great resolution rate but sometimes can result in the lacrimal pump dysfunction and canalicular scarring. The aim of this study is to introduce a minimally invasive approach, intracanalicular ophthalmic corticosteroid/antibiotic combination ointment infiltration (IOI, intracanalicular ointment infiltration), and to report our preliminary results for treating primary canaliculitis.In this retrospective, interventional case series, 68 consecutive patients with newly developed primary canaliculitis at a major tertiary eye center between January 2012 and January 2015. Thirty-six patients received conservative medical treatment alone (group 1; 36 eyes). Twenty-two patients and 10 medically uncontrolled patients from group 1 underwent IOI therapy (group 2; 32 eyes). Ten patients and 26 recurrent patients from group 1 and group 2 underwent surgery (group 3; 36 eyes). Patients were followed-up for at least 8 weeks. Clinical characteristics and outcomes were analyzed and compared.In this study, patients' age, sex, onset location, and durations of disease among 3 groups showed no significant difference. The resolution rate in group 2 was 72.7% (16/22) for new patients and 68.8% (22/32) for gross patients, respectively, both of which are higher than that of group 1 (22.2%, 10/36) but lower than that of group 3 (100%, 36/36). Of group 3, 2 patients received 2 surgical interventions and resolved finally. Microbiological workup was available in 51 patients. The most common isolates were staphylococcus species (27.9%) and streptococcus species (20%). Canalicular laceration developed in 1 patient during the IOI procedure and 1 patient undergoing surgery. Only 2 had postoperative lacrimal pump dysfunction and 1 had canalicular scarring in group 3.The IOI may be an effective and minimally invasive technique for treating primary canaliculitis and obviate the need for further intensive surgery.
[Show abstract][Hide abstract] ABSTRACT: Transforming growth factor alpha (TGFα) belongs to the epidermal growth factor (EGF) family and is known to play an important role during eyelid morphogenesis. In this study, we showed that ectopic expression of TGFα in the stroma of Kera-rtTA/tet-O-TGFα bitransgenic mice results in precocious eye opening, abnormal morphogenesis of the meibomian gland, tendon and tarsal plate malformation and epithelium hyperplasia. TGFα did not change proliferation and differentiation of meibocytes, but promoted proliferation and inhibited differentiation of the tarsal plate tenocytes. These results suggest that proper formation of the tendon and tarsal plate in the mouse eyelid is required for normal morphogenesis of the meibomian gland.
[Show abstract][Hide abstract] ABSTRACT: The optimal treatment strategy for an incomplete nasolacrimal duct obstruction (INDO) is still being debated. The aim of this study is to evaluate the treatment results of combined lacrimal passage probing and tobramycin/dexamethasone ophthalmic ointment infiltration (PIO, Probing and Injection) for INDO.In this retrospective, noncomparative case series, 397 consecutive adult patients with INDO treated at Shanghai Eye, Ear, Nose and Throat Hospital were enrolled. Records of the patients were reviewed. With the help of a modified 23-gauge lacrimal cannula, the PIO surgery was performed for the INDO-identified patients. The main outcome measures were resolution of tearing and complications. The relationship between successful outcome and clinical characteristics was analyzed.The surgery was performed successfully in all of the enrolled cases. No intraoperative complications were found in the procedure. The average follow-up time was 7.9 months. Three hundred patients (75.6%) experienced complete resolution of their symptoms after the surgery. Ninety-seven patients (24.4%) showed a partial improvement (1.8%), no improvement (18.4%), or a worsening of symptoms (4.3%). Of the 97 surgical-failure patients, 90 required silicone intubation or external dacryocystorhinostomy, and 94% were finally resolved. The most common postoperative complications were mild nasal bleeding in 41 patients, drug residues in 12 patients (6 developed the complete obstruction), and a slit punctum in 8 patients. Multivariate logistic regression analysis revealed that unilateral eye onset, not having a discharge at baseline, and not having postoperative drug residues were significant factors determining successful outcome.The PIO surgery is an effective, safe, timesaving, easy-to-perform, and minimally invasive technique for treating INDO.
[Show abstract][Hide abstract] ABSTRACT: Pharmacological blockade of N-acylethanolamine acid amidase (NAAA) activity is an available approach for inflammation and pain control through restoring the ability of endogenous PEA. But the recently reported NAAA inhibitors suffer from the chemical and biological unstable properties, which restrict functions of NAAA inhibition in vivo. It is still unrevealed whether systematic inhibition of NAAA could modulate PEA-mediated pain signalings. Here we reported an oxazolidinone imide compound 3-(6-phenylhexanoyl) oxazolidin-2-one (F96), which potently and selectively inhibited NAAA activity (IC50 = 270 nM). Intraperitoneal (i.p.) injection of F96 (3-30 mg/kg) dose-dependently reduced ear edema and restored PEA levels of ear tissues in 12-O-Tetradecanoylphorbol-13-acetate (TPA) induced ear edema models. Furthermore, F96 inhibited acetic acid-induced writhing and increased spared nerve injury induced tactile allodynia thresholds in a dose-dependent manner. Pharmacological effects of F96 (10 mg/kg, i.p.) on various animal models were abolished in PPAR-α(-/-) mice, and were prevented by PPAR-α antagonist MK886 but not by canabinoid receptor type 1 (CB1) antagonist Rimonabant nor canabinoid receptor type 2 (CB2) antagonist SR144528. Zebrafish embryos experiments showed better security and lower toxicity for F96 than ibuprofen. These results revealed that F96 might be useful in treating inflammatory and neuropathic pain by NAAA inhibition depending on PPAR-α receptors.
Full-text · Article · Aug 2015 · Scientific Reports
[Show abstract][Hide abstract] ABSTRACT: Each year, over 8,000 corneal transplantation surgeries are performed in China. Unlike developed countries, which have established standard requirements for operative experience for corneal specialists, little information exists on surgical training for keratoplasty in China. The aim of this study was to assess the keratoplasty experience of Chinese corneal specialists and to characterize their surgical patterns.
One hundred and twenty-one corneal specialists in 16 provinces (65 cities) in China were invited to complete an anonymous survey at the 2014 Chinese Corneal Society annual meeting, which consisted of questions with single or multiple-choice answers. Demographics, the number and type of keratoplasties performed, and the perceived limiting factors for performing keratoplasties were analyzed.
An overwhelming 89% response rate was achieved. Of the 108 respondents, 76% worked in tertiary centers, and only 23% held a medical doctorate degree. Furthermore, 69% of the participants had received corneal fellowship training of less than one year. Only 71% were capable of keratoplasties. Among those doing keratoplasty, 68% performed less than 50 keratoplasties each year. Of the same group of keratoplasty surgeons, 88% of corneal specialists capable of keratoplasties had performed penetrating keratoplasties, 87% had performed lamellar keratoplasties, 12% had performed deep anterior lamellar keratoplasties, and 5% had performed Descemet's stripping endothelial keratoplasties. When questioned on the reasons for the low number of keratoplasties performed in China, the respondents deemed the following factors most important: lack of surgical training (71%), a shortage of donor supply (52%), and a lack of curricula (42%). A multivariate logistic regression analysis showed that corneal transplantation capabilities are significantly associated with responders' education levels and training time.
Keratoplasty surgery experience is suboptimal for Chinese corneal specialists. Penetrating and lamellar keratoplasties are the preferred surgical patterns. Our findings raise concerns about the adequacy of keratoplasty training in China.
[Show abstract][Hide abstract] ABSTRACT: A variety of pluripotency reprogramming frequencies from different somatic cells has been observed, indicating cell origin is a critical contributor for efficiency of pluripotency reprogramming. Identifying the cell sources for efficient induced pluripotent stem cells (iPSCs) generation, and defining its advantages or disadvantages on reprogramming, is therefore important. Human ocular tissue-derived conjunctival epithelial cells (OECs) exhibited endogenous expression of reprogramming factors OCT4A (the specific OCT 4 isoform on pluripotency reprogramming) and SOX2. We therefore determined whether OECs could be used for high efficiency of iPSCs generation. We compared the endogenous expression levels of four pluripotency factors and the pluripotency reprograming efficiency of human OECs with that of ocular stromal cells (OSCs). Real-time PCR, microarray analysis, Western blotting and immunostaining assays were employed to compare OECiPSCs with OSCiPSCs on molecular bases of reprogramming efficiency and preferred lineage-differentiation potential. Using the traditional KMOS (KLF4, C-MYC, OCT4 and SOX2) reprogramming protocol, we confirmed that OECs, endogenously expressing reprogramming factors OCT4A and SOX2, yield very high efficiency of iPSCs generation (~1.5%). Furthermore, higher efficiency of retinal pigmented epithelial differentiation (RPE cells) was observed in OECiPSCs compared to OSCiPSCs or skin fibroblast iMR90iPSCs. The findings in this study suggest that conjunctival-derived epithelial (OECs) cells can be easier converted to iPSCs than conjunctival-derived stromal cells (OSCs). This cell type may also have advantages in retinal pigmented epithelial differentiation.
[Show abstract][Hide abstract] ABSTRACT: 4-Hydroxynonenal (4-HNE or HNE) is a main endogenous product of cellular lipid peroxidation in tissues and is reported to play pathogenic roles in eye diseases. Here we investigated the association between 4-HNE and oxidative stress in the corneal epithelium. 4-HNE suppressed the cell viability of human corneal epithelial cells (HCE) in a concentration dependent manner. 4-HNE significantly increased the level of 3-Nitrotyrosine (3-NT), a marker of oxidative stress, in HCE cells and corneal epithelium of rats by immunofluorescent staining and Western blot analysis. To its underlying mechanistic on ROS system, 4-HNE elevated the ROS generation enzyme NADPH oxidase 4 (NOX4) and induced the activation of NF-E2-related factor-2 (NRF2) and its downstream effectors: NAD(P)H dehydrogenase (quinone 1) (NQO1) and glutathione S-transferase P (GSTP). Furthermore, N-acetylcysteine (NAC), an antioxidant and ROS scavenger, antagonized the inhibitory and oxidant effects of 4-HNE on the corneal epithelial cells. In conclusion, 4-HNE plays an oxidant role in the corneal epithelium and this work provides a new strategy for the pathogenesis and treatment of corneal diseases.
No preview · Article · May 2015 · Scientific Reports
[Show abstract][Hide abstract] ABSTRACT: Netrins are secreted molecules involved in axon guidance and angiogenesis. However, the role of netrins in the vasculature remains unclear. Netrin-4 and netrin-1 have been found to be either pro- or antiangiogenic factors. Previously, we found that netrin-1 acts as an anti-angiogenic factor in rats by inhibiting alkali burn-induced corneal neovascularization. Here, we further investigate the effects of netrin-4, another member of the same netrin family, on neovascularization in vitro and in vivo. We found that netrin-4 functions similarly as netrin-1 in angiogenesis. In vitro angiogenesis assay shows that netrin-4 affected human umbilical vein endothelial cell (HUVEC) tube formation, viability and proliferation, apoptosis, migration, and invasion in a dose-dependent manner. Netrin-4 was topically applied in vivo to alkali-burned rat corneas on day 0 (immediately after injury) and/or day 10 post-injury. Netrin-4 subsequently suppressed and reversed corneal neovascularization. Netrin-4 inhibited corneal epithelial and stromal cell apoptosis, inhibited vascular endothelial growth factor (VEGF), but promoted pigment epithelium-derived factor (PEDF) expression, decreased NK-KB p65 expression, and inhibits neutrophil and macrophage infiltration. These results indicate that netrin-4 shed new light on its potential roles in treatmenting for angiogenic diseases that affect the ocular surface, as well as other tissues.
[Show abstract][Hide abstract] ABSTRACT: To compare the postoperative measurements of intraocular pressure (IOP) using the Corvis ST Tonometer (CST), ocular response analyzer (ORA), and Goldmann applanation tonometry (GAT) in eyes undergoing laser in situ keratomileusis (LASIK), as well as to analyze the relationship between the corneal biomechanical parameters of the CST and the ORA.
Fifty participants who had undergone LASIK to treat myopia in the previous 3 months were enrolled. Postoperative IOP measurements of these participants were obtained using the CST, ORA (corneal-compensated IOP [IOPcc], Goldmann-correlated IOP [IOPg]), and GAT. Device agreement was calculated by Bland-Altman analysis. The metrics of corneal biomechanical properties were recorded using the ORA and the CST. Corneal biomechanical parameters were compared.
The Bland-Altman analysis revealed a significant bias between CST and GAT, between CST and IOPcc, and between CST and IOPg of 3.4, 1.0, and 3.8, mm Hg, respectively, with 95% limits of agreement of -0.7 to 7.5 mm Hg, -2.1 to 4.2 mm Hg, and -0.4 to 8.0 mm Hg. The ORA-derived IOP measurements, CST-derived IOP, and GAT IOP values showed good correlation with each other. The CST IOP and IOPcc were higher than the GAT IOP (all p < 0.05), whereas IOPg did not differ from the GAT IOP readings. Ocular response analyzer-derived corneal biomechanical parameters (corneal hysteresis and the corneal resistance factor) showed significant correlations with CST-derived parameters, including the maximum deformation amplitude at the corneal apex and the time from start until the first applanation.
The CST offers an alternative method for measuring postoperative IOP in LASIK patients, and it appears to obtain higher IOP values than other tonometry techniques. The technique may facilitate the investigation of corneal biomechanical property changes in LASIK-treated eyes.
No preview · Article · Mar 2015 · Optometry and vision science: official publication of the American Academy of Optometry
[Show abstract][Hide abstract] ABSTRACT: Periostin is a non-structural matricellular protein. Little is known about periostin in human limbal stem cells (LSCs). This study was to explore the unique expression pattern and functional role of periostin in maintaining the properties of human LSCs. Fresh donor corneal tissues were used to make cryosections for evaluation of periostin expression on ex vivo tissues. Primary human limbal epithelial cells (HLECs) were generated from limbal explant culture. In vitro culture models for proliferation and epithelial regeneration were performed to explore functional role of periostin in LSCs. The mRNA expression was determined by reverse transcription and quantitative real-time PCR (RT-qPCR), and the protein production and localization were detected by immunofluorescent staining and Western blot analysis. Periostin protein was found to be exclusively immunolocalized in the basal layer of human limbal epithelium. Periostin localization was well matched with nuclear factor p63, but not with corneal epithelial differentiation marker Keratin 3. Periostin transcripts was also highly expressed in limbal than corneal epithelium. In primary HLECs, periostin expression at mRNA and protein levels was significantly higher in 50% and 70% confluent cultures at exponential growth stage than in 100% confluent cultures at slow growth or quiescent condition. This expression pattern was similar to other stem/progenitor cell markers (p63, integrin β1 and TCF4). Periostin expression at transcripts, protein and immunoreactivity levels increased significantly during epithelial regeneration in wound healing process, especially in 16-24 hours at wound edge, which was accompanied by similar upregulation and activation of p63, integrin β1 and TCF4. Our findings demonstrated that periostin is exclusively produced by limbal basal epithelium and co-localized with p63, where limbal stem cells reside. Periostin promotes HLEC proliferation and regeneration with accompanied activation of stem/progenitor cell markers p63, integrin β1 and TCF4, suggesting its novel role in maintaining the phenotype and functional properties of LSC.
[Show abstract][Hide abstract] ABSTRACT: Primary Sjögren's syndrome (pSS) is associated with HLA-DRB1 loci, but the association of amino acid variations in the hypervariable region of the HLA-DR β1 chain with pSS is largely unknown. In this study, we aimed to identify the amino acid variations within the hypervariable region of HLA-DRB1 molecule which are associated with the susceptibility to pSS. We sequenced the 2nd exon of the HLA-DRB1 locus in 52 pSS patients and 179 controls. The HLA-DRB1*0803 is the allele that shows the strongest association with pSS in Chinese population (OR = 3.0, P = 2.4 × 10−4). Furthermore, amino acid variations within the binding pocket P7 and P9 are associated with the susceptibility to pSS. An interaction between two residues within P7, β47 and β67, is associated with pSS. Structural modeling studies demonstrated that the electrostatics of peptide binding pocket 9 are opposite in pSS-susceptible and -protective HLA-DRB1 alleles. In conclusion, our results suggest that structural heterogeneity of the HLA-DRB1 peptide binding pocket P7 and P9 might play a role in the pathogenesis of pSS.
Full-text · Article · Jan 2015 · Journal of Autoimmunity
[Show abstract][Hide abstract] ABSTRACT: to test the effectiveness of breast feeding (BF), music therapy (MT), and combined breast feeding and music therapy (BF+MT) on pain relief in healthy-term neonates during heel lance.Designrandomised controlled trial.Settingin the postpartum unit of one university-affiliated hospital in China from August 2013 to February 2014.Participantsamong 288 healthy-term neonates recruited, 250 completed the trial. All neonates were undergoing heel lancing for metabolic screening, were breast fed, and had not been fed for the previous 30 minutes.Interventionsall participants were randomly assigned into four groups – BF, MT, BF+MT, and no intervention – with 72 neonates in each group. Neonates in the control group received routine care. Neonates in the other three intervention groups received corresponding interventions five minutes before the heel lancing and throughout the whole procedure.MeasurementsNeonatal Infant Pain Scale (NIPS), latency to first cry, and duration of first crying.Findingsmean changes in NIPS scores from baseline over time was dependent on the interventions given. Neonates in the BF and combined BF+MT groups had significantly longer latency to first cry, shorter duration of first crying, and lower pain mean score during and one minute after heel lance, compared to the other two groups. No significant difference in pain response was found between BF groups with or without music therapy. The MT group did not achieve a significantly reduced pain response in all outcome measures.ConclusionsBF could significantly reduce pain response in healthy-term neonates during heel lance. MT did not enhance the effect of pain relief of BF.Implications for practicehealthy-term neonates should be breast fed to alleviate pain during heel lance. There is no need for the additional input of classical music on breast feeding in clinic to relieve procedural pain. Nurses should encourage breast feeding to relieve pain during heel lance.