[Regulatory Effect of Vitamin D on Renin Expression at Maternal-Fetal Interface].

Objective: To investigate the regulatory effect and mechanism of vitamin D on the local renin-angiotensin system at maternal-fetal interface in the pathological process of preeclampsia (PE). Methods: The mRNA and protein expression of renin in decidua of normal pregnancy and PE placentas was determined by RT-PCR and Western blot. Normal decidual tissues were treated with active and inactive vitamin D for 48 h in vitro and the expressions of renin and vitamin D deactivating enzyme CYP24A1 were determined by RT-PCR and Western blot. Normal decidual stromal cells and glandular epithelial cells were isolated and purified, and identified by immunocytochemical staining. RT-PCR was used to examine the mRNA of vdr, cyp27 b1, cyp24 a1, and renin in the two types of cells and in decidual tissue, and the mRNA products were subjected to gel electrophoresis. These two cell types were treated with active and inactive vitamin D in vitro and the expressions of renin and vitamin D deactivating enzyme CYP24A1 were determined by RT-PCR and Western blot. Decidual gland epithelial cells were treated with protein kinase A (PKA) activator forskolin or inhibitor H89 to explore the interaction between PKA pathway and vitamin D in the regulation of renin expression. Results: The expression of renin in PE decidua was significantly higher than that of normal control at transcriptional and translational levels ( P<0.05). Vitamin D treatment could significantly down-regulate the expression of renin in normal decidua tissues ( P<0.05), while it significantly up-regulated CYP24A1 expression ( P<0.001). Decidual stromal cells and gland epithelial cells were successfully isolated from decidual tissue. Compared with that in decidual stromal cells, the mRNA level of vitamin D-related molecules in gland epithelial cells was more similar to that in decidual tissue. Active or inactive vitamin D treatment significantly inhibited the expression of renin in glandular epithelial cells ( P<0.05), but the expression of renin in decidual stromal cells was not affected. However, the treatment of active or inactive vitamin D in these two kinds of cells significantly increased the expression of CYP24A1 ( P<0.001). Active vitamin D could significantly inhibit the upregulation of renin by PKA agonist forskolin, and could inhibit the expression of renin through synergy with PKA inhibitor H89. Conclusion: The expression of renin in placental decidua is up-regulated in patients with PE, and the activation of local renin-angiotensin system at the maternal-fetal interface may be involved in the pathogenesis of PE. Vitamin D can specifically down-regulate renin expression in human decidual gland epithelial cells by competing with the PKA pathway. Vitamin D supplementation may have potential value for clinical intervention of PE.

Anti-fibrosis potential of pirarubicin via inducing apoptotic and autophagic cell death in rabbit conjunctiva.

This study investigated the potential efficacy of pirarubicin (THP) in modulating rabbit conjunctival fibrosis both in vitro and in vivo and characterized the underlying mechanisms. Primary rabbit conjunctival fibroblasts (RCF) were cultured and treated with THP or mitomycin C (MMC) for 5 min, followed by assaying for cell viability, cell cycle distribution, apoptotic and autophagic pathways. The production of reactive oxygen species (ROS) and chemotaxis of macrophages by RCF were evaluated using 2',7'-dichlorofluorescein diacetate (DCFH-DA) labeling and transwell migration assay, respectively. Limbal stem cell excision in combination with alkali burn was performed on the rabbits to establish a model of limbal deficiency and conjunctival fibro-vascular invasion. After three months, the modeled fibro-vascular tissue was excised combined with topical subconjunctival 5-min exposure to THP compared with MMC intraoperatively. The recurrence of postoperative fibrosis and the expression of apoptosis, autophagy, and inflammation markers were evaluated by immunohistochemistry. All modeled rabbits developed conjunctival fibro-vascular lesions, which were similar to human recurrent pterygium (HRP). Both THP and MMC inhibited RCF proliferation and arrested cell cycle at the G0/G1 phase. In particular, 7.5 µmol/L THP remarkably promoted RCF autophagy by upregulating the levels of Beclin 1, Atg 5/12 conjugate, and LC3B, whereas, 15 µmol/L THP significantly triggered a cascade of mitochondrial-associated RCF apoptosis. THP induced the production of ROS and enhanced the chemoattraction of macrophages by RCF. Similar to 600 µmol/L MMC, both 7.5 µmol/L and 15 µmol/L THP attenuated postoperative conjunctival fibrosis in the models; 7.5 µmol/L THP preferentially enhanced autophagy while causing fewer side effects. THP exerted its antifibrotic action by modulating autophagy in RCF, inducing cell cycle arrest, and mitochondrial-mediated apoptosis. THP at the dose of 7.5 µmol/L prevented postoperative conjunctival fibrosis in an animal model.

Analysis of the VSX1 gene in sporadic keratoconus patients from China.

BACKGROUND: Keratoconus normally presents as a sporadic disease. Although different studies have found sequence variants of the visual system homeobox 1 (VSX1) gene associated with keratoconus in humans, no research has detected such variants in sporadic keratoconus patients from China. To investigate the possibility of VSX1 being a candidate susceptibility gene for Chinese patients with sporadic keratoconus, we performed sequence screening of this gene in such patients. METHODS: Whole DNA was obtained from the leukocytes in the peripheral venous blood of 50 patients with sporadic keratoconus and 50 control subjects without this ocular disorder. Polymerase chain reaction single-strand conformation polymorphism analysis and direct DNA sequencing technology were used to detect sequence variation in the five exons and splicing regions of the introns of the VSX1 gene. The sequencing results were analyzed using DNAstar software. RESULTS: One novel missense heterozygous sequence variant (p.Arg131Pro) was found in the first exon of the VSX1 gene in one keratoconus patient. Another heterozygous sequence variant (p.Gly160Val) in the second exon was found in two keratoconus patients. These variants were not detected in the control subjects. In the third intron of the VSX1 gene, c.8326G > A nucleotide substitution (including heterozygous and homozygous change) was also discovered. The frequency of this variation did not differ significantly between patients and controls, it should belong to single-nucleotide polymorphism of the VSX1 gene. Bioinformatic analysis also predicted that one missense sequence variation (p.Arg131Pro) may not cause a pathogenic change. CONCLUSIONS: In this study, we added one novel missense sequence variation (p.Arg131Pro) in the coding region of the VSX1 gene to the range of VSX1 coding region variations observed in patients with sporadic keratoconus from China. Our work suggests that VSX1 sequence variants might be involved in the pathogenesis of sporadic keratoconus, but their precise role in disease causation requires further investigation.

New histopathologic and ultrastructural findings in Reis-Bücklers corneal dystrophy caused by the Arg124Leu mutation of TGFBI gene.

BACKGROUND: Reis-Bücklers corneal dystrophy (RBCD) was consistently reported as a corneal dystrophy only affected Bowman's layer and superficial corneal stroma, and superficial keratectomy was a recommendation surgery for treatment in literatures. The study reported new histopathological and ultrastructural findings in RBCD caused by the Arg124Leu mutation of transforming growth factor induced (TGFBI) gene in a four-generation Chinese pedigree. METHODS: Subjects including eight patients and seven unaffected family members received slit-lamp biomicroscopy and photography. DNA was obtained from all subjects, and exons 4 and 11 to 14 of TGFBI gene were analyzed by polymerase chain reaction and the products were sequenced. Anterior segment optical coherence tomography (AS OCT) and in vivo confocal microscopy were conducted for ten eyes of five patients. Based on the results of AS OCT and in vivo confocal microscopy, deep anterior lamellar keratoplasty (DLKP) using cryopreserved donor cornea was applied for four eyes of four patients. Four lamellar dystrophic corneal buttons were studied by light and transmission electron microscopy, and TGFBI immunohistochemistry. RESULTS: Eight patients had typical clinical manifestations of RBCD presenting recurrent painful corneal erosion starting in their early first decades, along with age-dependent progressive geographic corneal opacities. TGFBI sequencing revealed a heterozygous mutation, Arg124Leu in all eight patients. Anterior segment optical coherence tomography and in vivo confocal microscopy showed the dystrophic deposits involved not only in subepithelial and superficial stroma, but also in mid- or posterior stroma in four examined advanced eyes. Light microscopy showed Bowman's layer was absent, replaced by abnormal deposits stain bright red with Masson's trichrome. In superficial cornea, the deposits stacked and produced three to five continuous bands parallel to the corneal collagen lamellae. In mid- to posterior stroma, numerous granular or dot- like aggregates were heavily scattered, and most of them presented around the nuclei of stromal keratocytes. Transmission electron microscopy revealed the multiple electron-dense rod-shaped deposits aggregated and formed a characteristic pattern of three to five continuous bands in superficial cornea, which were similar to those seen under light microscopy. In mid- to posterior stroma, clusters of rod-shaped bodies were scattered extracellular or intracellular of the stromal keratocytes between the stromal lamellae suggesting the close relationship between mutated proteins and keratocyte. CONCLUSIONS: The study offer evidences indicating DLKP is a viable treatment option for advanced RBCD to avoid recurrence, and the mutated TGFBIp in dystrophic corneas are of keratocytes origin.

Increased interleukin 1ß levels in the subacromial fluid in diabetic patients with rotator cuff lesions compared with nondiabetic patients.

BACKGROUND: Diabetic patients have a high prevalence of shoulder pain and stiffness. Interleukin (IL) 1ß was reportedly correlated with shoulder stiffness and decreased shoulder function. We retrospectively compared the expression of IL-1ß in the subacromial synovial fluid between diabetic and nondiabetic patients with rotator cuff tearing. MATERIALS AND METHODS: We enrolled 68 patients with rotator cuff tearing (23 diabetic patients and 45 nondiabetic patients). The preoperative sum of range-of-motion deficit (SROMD), Constant score, and visual analog scale (VAS) score were obtained. Intraoperatively, subacromial synovial fluid was collected for the IL-1ß level measurement. Comparisons of IL-1ß levels, Constant scores, SROMD, and VAS scores between diabetic and nondiabetic patients were analyzed with the Mann-Whitney U test. RESULT: Diabetic patients with rotator cuff tearing had significantly increased subacromial IL-1ß levels (P = .048), SROMD (P < .001) and VAS scores (P = .022) and lower Constant scores (P < .001) than nondiabetic patients. The IL-1ß levels in the subacromial fluid were significantly correlated with the Constant score (r = -0.477, P < .001), VAS score (r = 0.698, P < .001), and SROMD (r = 0.293, P = .015) in all patients. CONCLUSION: The elevated IL-1ß levels in the subacromial fluid of patients with diabetes may explain the likelihood of pain and shoulder stiffness developing in these patients. We suggest more aggressive treatment for rotator cuff lesions in diabetic patients.