Total Synthesis of a TNBC-Selective Cytotoxic Bromo Nor-eremophilane, PC-A, and Its Preliminary Structure-Activity Relationships.

PC-A (1), a bromo nor-eremophilane, showed selective antiproliferative activity against a triple-negative breast cancer (TNBC) cell line. This unique activity prompted us to establish a total synthesis to facilitate a structure-activity relationship (SAR) study and selectivity optimization. An enantioselective first total synthesis of 1 was achieved starting from (R)-carvone through a side chain extension with a Mukaiyama aldol reaction and decalin construction. The synthesized decalin derivatives and debromo PC-A (2) were evaluated for antiproliferative activity against five human tumor cell lines, including TNBC, to assess preliminary SAR correlations.

Cross-cultural comparison of continuous deep sedation for advanced cancer patients in East Asian countries: prospective cohort study.

OBJECTIVE: Cultural, social, and legal factors have been known to affect physicians' practice of continuous deep sedation. There have been few quantitative studies to compare continuous deep sedation practice in Asian countries. We aimed to describe and compare clinical characteristics of continuous deep sedation in Japan, Korea and Taiwan. METHODS: Patients with advanced cancer admitted to participating palliative care units were enrolled from January 2017 to September 2018. We evaluated and compared (i) the prevalence of continuous deep sedation, (ii) the characteristics of sedated and non-sedated groups in each country, and (iii) continuous deep sedation administration patterns among the three countries. RESULTS: A total of 2158 participants were included in our analysis, and 264 received continuous deep sedation. The continuous deep sedation prevalence was 10, 16 and 22% in Japan, Korea and Taiwan, respectively. Delirium was the most frequent target symptom in all countries, along with dyspnoea (in Japan) and psychological symptoms (in Korea). Midazolam was most frequently used in Japan and Taiwan, but not in Korea (P < 0.001). Among the patients receiving continuous deep sedation, the hydration amount on the final day was significantly different, with median volumes of 200, 500 and 0 mL in Japan, Korea and Taiwan, respectively (P < 0.001). In Korea, 33% of the continuous deep sedation administration caused a high degree of physicians' discomfort, but 3% in Japan and 5% in Taiwan (P < 0.001). CONCLUSIONS: Clinical practices of continuous deep sedation and physicians' discomfort related to continuous deep sedation initiation highly varied across countries. We need to develop optimal decision-making models of continuous deep sedation and hydration during continuous deep sedation in each country.

Novel cancer-specific epidermal growth factor receptor antibody obtained from the serum of esophageal cancer patients with long-term survival.

Although esophageal cancer has a poor prognosis after recurrence, some patients have shown long-term survival despite recurrence. We hypothesized that induction of either antitumor Abs or antitumor-specific CTLs could play a role in long-term survival (5 years or longer) in patients with recurrence and/or distant metastases. Therefore, we aimed to obtain Abs that specifically bind to cancer cells by using serum samples from patients with a good prognosis. A phage library was prepared using PBMC mRNA of the patients, and cell panning was carried out using an esophageal cancer cell line. Results showed the presence of an epidermal growth factor receptor (EGFR) Ab, KT112, that specifically bound to the cancer cell line. Notably, KT112 bound to only EGFR-positive cancer cells but failed to bind to normal esophageal cells. Furthermore, KT112 was characterized by responses to EGFR expressed on cancer cells but not to the recombinant extracellular domain of EGFR. Immunohistochemical analysis showed that KT112 reacted with 17.4% of esophageal squamous cell carcinoma tissue but not with any other cancer or normal tissue, suggesting that the Ab recognizes cancer-specific forms of EGFR and might have contributed to tumor suppression in patients with esophageal cancer. Furthermore, because of its high cancer specificity, KT112 could be a promising therapeutic option (e.g., in Ab-drug conjugates) for esophageal cancer.

Continuous deep sedation at the end of life in children with cancer: experience at a single center in Japan.

Continuous deep sedation (CDS) is used to alleviate unbearable and otherwise refractory symptoms in patients dying of cancer. No data are available concerning CDS in children from Japan to date. This study primarily aimed to describe experience in CDS in child cancer patients at Kyoto University Hospital. The secondary aims were to identify the characteristics of patients who received CDS, and to assess ability in daily living at the end of life. A retrospective chart review was performed for child cancer patients who died at the institute between 2008 and 2017. The data of 35 patients were analyzed. Nine (26%) patients had received CDS. Indications for CDS were dyspnea (56%), agitation (22%), seizures (22%), and pain (11%). Midazolam was used in all nine cases. In eight (89%) patients, opioids were also prescribed. In seven (78%) patients, CDS was performed for < 48 hours. In all nine cases, consent was obtained from the parent(s) but not from the children. CDS was more likely in patients with solid tumors (p = 0.018) and those who had received no respite sedation (p = 0.002). Patients without central nervous system symptoms tended to maintain their capacity for oral intake and verbal communication until a few days prior to death. This is the first report on CDS in child cancer patients from Japan. In the CDS literature, cross-study differences are evident for incidence, target symptoms, duration, and the decision-making process. Further international discussion is warranted concerning indications for CDS and the decision-making process.

Changes in opinions on palliative sedation of palliative care specialists over 16 years and their effects on clinical practice.

PURPOSES: Despite extensive debate on palliative sedation over the last few decades, no studies have explored longitudinal changes in physicians' opinion. Moreover, little is known about how physicians' opinions affect their practice. This study aimed to clarify (1) changes in palliative care specialists' opinions on palliative sedation and (2) the effects of these opinions on clinical practice. METHODS: In 2000 and 2016, nationwide questionnaire surveys involving Japanese palliative care specialists were performed: measurement was based on agreement with opinions on palliative sedation. In 2016, the physicians reported their practice of continuous deep sedation (CDS) and answered their thoughts on what factors lead to a good death as factors potentially affecting their practice. RESULTS: Of the 695 physicians enrolled in the 2016 survey, 469 responded (67%) and 417 were analyzed (60%). Compared with 54 physicians in 2000, the present respondents were more likely to consider palliative sedation is difficult to perform based on appropriate indications (ES = 0.84, P < 0.001), is unnecessary if conventional palliative care is performed sufficiently (ES = 0.30, P = 0.013), and may result in legal action (ES = 0.35, P = 0.003). The physicians' opinions more strongly affected their practice than their characteristics or thoughts on good death components. CONCLUSIONS: Recently, palliative care specialists in Japan tend to encounter more difficulties determining what conventional palliative care is and what palliative sedation is. They also fear legal ramifications. It is necessary to standardize methods of alleviating patients' suffering, to make CDS criteria clearer, and to create a legal basis that respects patients' rights at their end of life.

Pigment epithelium-derived factor improves metabolic derangements and ameliorates dysregulation of adipocytokines in obese type 2 diabetic rats.

Oxidative stress and inflammation in the adipose tissues contribute to the metabolic syndrome. Pigment epithelium-derived factor (PEDF) inhibits vascular inflammation through its anti-oxidative properties. However, it remains unclear whether PEDF could suppress adipocyte inflammation. We investigated the effects of long-term administration or suppression of PEDF on adipocyte inflammation and metabolic derangements in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an animal model of type 2 diabetes with insulin resistance. Circulating and adipose tissue PEDF levels were increased as OLETF rats became more obese and insulin resistant. Long-term administration of PEDF improves metabolic parameters, ameliorates dysregulation of adipocytokines, and suppresses NADPH oxidase-induced oxidative stress and macrophage infiltration in the adipose tissues of OLETF rats, whereas these variables are exacerbated by the knockdown of PEDF by administering siRNAs. Our study suggests that PEDF could improve metabolic derangements by suppressing the inflammatory and oxidative reactions in adipose tissues of OLETF rats. PEDF levels may be elevated as a countersystem against obesity-related metabolic derangements.

Development of CMV retinitis in an antigenemia-negative infant after cord blood transplantation.

A five-month-old male infant with familial hemophagocytic lymphohistiocytosis underwent cord blood transplantation using reduced-intensity conditioning. Methylprednisolone (mPSL) pulse administration was performed for marked pulmonary edema during the early phase of transplantation, followed by GVHD treatment with mPSL until day 100. CMV antigenemia was detected on days 27 and 55, but serum became negative with 2- to 3-week ganciclovir (GCV) treatment on both occasions. On day 120, ophthalmological findings included multiple bilateral white spots and a positive PCR study using anterior chamber fluid confirmed the diagnosis of CMV retinitis affecting both eyes, although CMV antigenemia was negative. Re-treatment with GCV had a minimal effect on the ophthalmological findings, while foscarnet administration markedly improved the retinitis and decreased the CMV-DNA level. Considering that a substantial proportion of patients develop CMV retinitis even when CMV antigenemia is not present, routine monitoring involving ophthalmological examinations should be conducted for hematopoietic transplant patients, especially infants, who cannot complain of ocular symptoms.

DNA aptamer raised against advanced glycation end products inhibits melanoma growth in nude mice.

Epidemiological studies have suggested that diabetes is associated with an increased risk of cancer. However, the underlying molecular mechanism remains unclear. We investigated here whether DNA aptamer directed against advanced glycation end products (AGE-aptamer) inhibited melanoma growth in nude mice. G361 melanoma cells were injected intradermally into the upper flank of athymic nude mice. Mice received continuous intraperitoneal infusion (0.136 µg/day) of either AGE-aptamer (n=9) or Control-aptamer (n=8) by an osmotic mini pump. Tumor volume was measured at 4-day interval, and G361 melanoma was excised at day 43 after the aptamer treatment. We further examined the effects of AGE-aptamer on proliferation of AGE-exposed endothelial cells and G361 cells. AGE-aptamer significantly inhibited the in vivo-tumor growth of G361 melanoma. Immunohistochemical and western blotting analyses of G361 melanoma revealed that AGE-aptamer decreased expression levels of proliferating nuclear antigen, CD31 and Mac-3, markers of endothelial cells and macrophages, respectively. AGE-aptamer significantly decreased the number of tumor-associated vessels. AGE, receptor for AGE (RAGE) and vascular endothelial growth factor levels were also reduced in AGE-aptamer-treated G361 melanoma. AGE-aptamer inhibited the AGE-induced proliferation and tube formation of endothelial cells as well as the growth of G361 cells in vitro. The present findings suggest that AGE-aptamer could inhibit the AGE-RAGE axis in G361 melanoma and resultantly suppress the tumor growth in nude mice by blocking the angiogenesis. AGE-aptamer might be a novel therapeutic strategy for preventing the progression of malignant melanoma in diabetes.

Glucagon-like peptide-1 receptor agonist inhibits asymmetric dimethylarginine generation in the kidney of streptozotocin-induced diabetic rats by blocking advanced glycation end product-induced protein arginine methyltranferase-1 expression.

Advanced glycation end products (AGEs) and their receptor (RAGE) play a role in diabetic nephropathy. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, contributes to diabetic nephropathy. We have found that glucagon-like peptide-1 (GLP-1) inhibits the AGE-induced inflammatory reactions in endothelial cells. However, effects of GLP-1 on the AGE-RAGE-ADMA axis are unknown. This study examined the effects of GLP-1 on reactive oxygen species (ROS) generation, gene expression of protein arginine methyltransfetase-1 (PRMT-1), an enzyme that mainly generates ADMA, and ADMA levels in human proximal tubular cells. Streptozotocin-induced diabetic rats received continuous i.p. infusion of 0.3 µg of vehicle or 1.5 µg of the GLP-1 analog exendin-4 per kilogram of body weight for 2 weeks. We further investigated whether and how exendin-4 treatment reduced ADMA levels and renal damage in streptozotocin-induced diabetic rats. GLP-1 inhibited the AGE-induced RAGE and PRMT-1 gene expression, ROS, and ADMA generation in tubular cells, which were blocked by small-interfering RNAs raised against GLP-1 receptor. Exendin-4 treatment decreased gene expression of Rage, Prmt-1, Icam-1, and Mcp-1 and ADMA level; reduced urinary excretions of 8-hydroxy-2'-deoxyguanosine and albumin; and improved histopathologic changes of the kidney in diabetic rats. Our present study suggests that GLP-1 receptor agonist may inhibit the AGE-RAGE-mediated ADMA generation by suppressing PRMT-1 expression via inhibition of ROS generation, thereby protecting against the development and progression of diabetic nephropathy.

Switching to multiple daily injection therapy with glulisine improves glycaemic control, vascular damage and treatment satisfaction in basal insulin glargine-injected diabetic patients.

BACKGROUND: Basal and bolus insulin therapy is required for strict blood control in diabetic patients, which could lead to prevention of vascular complications in diabetes. However, the optimal combination regimen is not well established. METHODS: Fifty-nine diabetic patients (49 type 1 and 10 type 2; 52.9 ± 13.3 years old) whose blood glucose levels were uncontrolled (HbA1c > 6.2%) by combination treatment of basal insulin glargine with multiple daily pre-meal injections of bolus short-acting insulin [aspart (n = 19), lispro (n = 37) and regular human insulin (n = 3)] for at least 8 weeks were enrolled in this study. We examined whether glycaemic control and vascular injury were improved by replacement of short-acting insulin with glulisine. Patient satisfaction was assessed with Diabetes Treatment Satisfaction Questionnaire. RESULTS: Although bolus and basal insulin doses were almost unchanged before and after replacement therapy, switching to glulisine insulin for 24 weeks significantly decreased level of HbA1c , advanced glycation end products (AGEs), soluble receptor for AGEs (sRAGE), monocyte chemoattractant protein-1 (MCP-1) and urinary albumin excretion. In multiple stepwise regression analysis, change in MCP-1 values from baseline (ΔMCP-1) was a sole determinant of log urinary albumin excretion. ΔAGEs and ΔsRAGE were independently correlated with each other. The relationship between ΔMCP-1 and ΔsRAGE was marginally significant (p = 0.05). Replacement of short-acting insulin by glulisine significantly increased Diabetes Treatment Satisfaction Questionnaire scores. CONCLUSIONS: Our present study suggests that combination therapy of glargine with multiple daily pre-meal injections of glulisine might show superior efficacy in controlling blood glucose, preventing vascular damage and improving treatment satisfaction in diabetic patients.

An endobronchial inflammatory myofibroblastic tumor in a 10-yr-old child after allogeneic hematopoietic cell transplantation.

IMTs belong to the group of soft tissue tumor and could occur at any anatomical site; however, the causes and growth feature remain unclear. This case report documents a 10-yr-old male suffering from slowly developing dyspnea on exertion and cough around seven months post-HCT. He was diagnosed with an endobronchial tumor based on imaging, and histology confirmed ALK-positive submucosal spindle-shaped cells with infiltrative cells, compatible with IMT. We should be aware that IMT is a potential complication of pediatric allogeneic HCT and can cause sudden airway obstruction.

Munc13-4 deficiency with CD5 downregulation on activated CD8+ T cells.

Familial hemophagocytic lymphohistiocytosis (FHL) is characterized by uncontrolled activation of T cells and macrophages and hypercytokinemia. We have recently described a significant increase in a subpopulation of CD8(+) T cells with downregulation of CD5 during the acute phase of FHL type2 (FHL2; perforin deficiency), which declines after successful treatment, with a concomitant reduction in serum cytokine level. This unusual subset of CD8(+) T cells, however, has not been characterized in patients with other subtypes of FHL. Herein, we describe a patient with FHL3 (Munc13-4 deficiency) carrying compound heterozygous mutations in the UNC13D gene. He had high serum levels of pro-inflammatory cytokines and significantly increased activated CD8(+) T cells with downregulation of CD5 during the acute phase, similar to that found in FHL2. This immunophenotypic feature may serve as a useful marker of immune dysregulation in FHL3 in addition to FHL2.

Acute lymphoblastic leukemia in a girl with Wilson's disease.

Wilson's disease (WD) is an autosomal recessive defect in cellular copper transportation. Although acute lymphoblastic leukemia (ALL) is the most common form of childhood malignancy, only two cases of ALL associated with WD have been reported to date. One patient died of relapse and infection, and the other died of neutropenic sepsis during the treatment. We here describe the case of a 10-year-old girl with WD and ALL. Adverse events of chemotherapy, including liver toxicity and severe myelosuppression, necessitated adjustments in the chemotherapy doses. After completion of the treatment, the patient has remained in remission from ALL without progression of liver damage for 2 years. Severe treatment-related toxicity should be considered in chemotherapy for patients with WD.

Role of advanced glycation end products (AGEs) and oxidative stress in vascular complications in diabetes.

BACKGROUND: A non-enzymatic reaction between reducing sugars and amino groups of proteins, lipids and nucleic acids contributes to the aging of macromolecules, whose process has been known to progress at an accelerated rate under hyperglycemic and/or oxidative stress conditions. Over a course of days to weeks, early glycation products undergo further reactions such as rearrangements and dehydration to become irreversibly cross-linked, fluorescent protein derivatives termed advanced glycation end products (AGEs). SCOPE OF REVIEW: In this paper, we review the role of AGE-oxidative stress axis and its therapeutic interventions in vascular complications in diabetes. MAJOR CONCLUSIONS: AGEs elicit oxidative stress generation and subsequently cause inflammatory and thrombogenic reactions in various types of cells via interaction with a receptor for AGEs (RAGE), thereby being involved in vascular complications in diabetes. In addition, mitochondrial superoxide generation has been shown to play an important role in the formation and accumulation of AGEs under diabetic conditions. Further, we have recently found that a pathophysiological crosstalk between AGE-RAGE axis and renin-angiotensin system (RAS) could contribute to the progression of vascular damage in diabetes. GENERAL SIGNIFICANCE: These observations suggest that inhibition of AGE-RAGE-oxidative stress axis or blockade of its interaction with RAS is a novel therapeutic strategy for preventing vascular complications in diabetes.

Advanced glycation end products evoke endothelial cell damage by stimulating soluble dipeptidyl peptidase-4 production and its interaction with mannose 6-phosphate/insulin-like growth factor II receptor.

BACKGROUND: Advanced glycation end products (AGEs) and receptor RAGE interaction play a role in diabetic vascular complications. Inhibition of dipeptidyl peptidase-4 (DPP-4) is a potential therapeutic target for type 2 diabetes. However, the role of DPP-4 in AGE-induced endothelial cell (EC) damage remains unclear. METHODS: In this study, we investigated the effects of DPP-4 on reactive oxygen species (ROS) generation and RAGE gene expression in ECs. We further examined whether an inhibitor of DPP-4, linagliptin inhibited AGE-induced soluble DPP-4 production, ROS generation, RAGE, intercellular adhesion molecule-1 (ICAM-1) and plasminogen activator inhibitor-1 (PAI-1) gene expression in ECs. RESULTS: DPP-4 dose-dependently increased ROS generation and RAGE gene expression in ECs, which were prevented by linagliptin. Mannose 6-phosphate (M6P) and antibodies (Ab) raised against M6P/insulin-like growth factor II receptor (M6P/IGF-IIR) completely blocked the ROS generation in DPP-4-exposed ECs, whereas surface plasmon resonance revealed that DPP-4 bound to M6P/IGF-IIR at the dissociation constant of 3.59 x 10⁻5 M. AGEs or hydrogen peroxide increased soluble DPP-4 production by ECs, which was prevented by N-acetylcysteine, RAGE-Ab or linagliptin. Linagliptin significantly inhibited the AGE-induced ROS generation, RAGE, ICAM-1 and PAI-1 gene expression in ECs. CONCLUSIONS: The present study suggests that AGE-RAGE-induced ROS generation stimulates the release of DPP-4 from ECs, which could in turn act on ECs directly via the interaction with M6P/IGF-IIR, further potentiating the deleterious effects of AGEs. The blockade by linagliptin of positive feedback loop between AGE-RAGE axis and DPP-4 might be a novel therapeutic target for vascular injury in diabetes.

Sodium-glucose cotransporter 2-mediated oxidative stress augments advanced glycation end products-induced tubular cell apoptosis.

BACKGROUND: Ninety percent of glucose filtered by the glomerulus is reabsorbed by a sodium-glucose cotransporter 2 (SGLT2), which is expressed mainly on the apical membrane of renal proximal tubules. Because blockade of SGLT2 promotes urinary glucose excretion and thereby improves hyperglycaemia, selective inhibition of SGLT2 has been proposed as a potential therapeutic target for the treatment of patients with diabetes. Moreover, advanced glycation end products (AGEs)-receptor (RAGE) system induces apoptosis of tubular cells, thereby playing a role in diabetic nephropathy as well. However, the pathophysiological crosstalk of SGLT2 with AGEs-RAGE axis and its role in diabetic nephropathy remains unknown. METHODS: This study investigated whether and how blockade of SGLT2 could prevent AGEs-elicited apoptosis of high glucose-exposed proximal tubular cells in vitro. RESULTS: SGLT2 was expressed in tubular cells. Tubular SGLT2 expression and glucose entry into the cells were completely blocked by the treatment with small interfering RNAs (siRNAs) raised against SGLT2. High glucose increased reactive oxygen species generation and RAGE expression levels in tubular cells, both of which were partly suppressed by SGLT2 siRNAs or an antioxidant, N-acetylcysteine. Further, high glucose was found to augment the AGEs-induced tubular cell apoptosis, which was also inhibited by SGLT2 siRNAs. CONCLUSIONS: Our present data suggest that SGLT2-mediated, high glucose-induced reactive oxygen species generation could augment the AGEs-induced apoptotic cell death of tubular cells via RAGE induction. SGLT2 may play some role in tubular apoptosis in diabetic nephropathy.

Beneficial effects of vildagliptin on retinal injury in obese type 2 diabetic rats.

BACKGROUND/AIMS: Vildagliptin is an oral inhibitor of dipeptidyl peptidase-4, an enzyme mainly responsible for inactivating incretins, and one of the widely used drugs for the treatment of type 2 diabetes. However, effects of vildagliptin on retinal injury in diabetes remain unclear. We examined here whether oral administration of vildagliptin inhibited gene expression of inflammatory and thrombogenic parameters in Otsuka Long-Evans Tokushima Fatty rats (OLETF rats), an animal model of obese type 2 diabetes. METHODS: OLETF rats at 22 weeks of age were given vehicle or 3 mg/kg of vildagliptin for another 10 weeks. Gene expression was analyzed in quantitative real-time reverse transcription-polymerase chain reaction. RESULTS: Vildagliptin significantly inhibited the increase in body weight and decreased average fasting blood glucose in the OLETF rats. Compared with 22-week-old OLETF rats, gene expression levels of vascular endothelial growth factor, intercellular adhesion molecule-1, plasminogen activator inhibitor-1 and pigment epithelium-derived factor were significantly increased in the retinas of OLETF rats at 32 weeks of age, all of which were inhibited by treatment with vildagliptin. CONCLUSIONS: The present study demonstrated for the first time that vildagliptin inhibited inflammatory and thrombogenic reactions in the retinas of obese type 2 diabetic rats. Vildagliptin may play a protective role against diabetic retinopathy.

Continuous Deep Sedation for Psycho-Existential Suffering: A Multicenter Nationwide Study.

Background: There is ongoing debate on whether continuous deep sedation (CDS) for psycho-existential suffering is appropriate. Objective: We aimed to (1) clarify clinical practice of CDS for psycho-existential suffering and (2) assess its impact on patients' survival. Methods: Advanced cancer patients admitted to 23 palliative care units in 2017 were consecutively enrolled. We compared patients' characteristics, CDS practices, and survival between those receiving CDS for psycho-existential suffering ± physical symptoms and only for physical symptoms. Results: Of 164 patients analyzed, 14 (8.5%) received CDS for psycho-existential suffering ± physical symptoms and only one of them (0.6%) solely for psycho-existential suffering. Patients receiving CDS for psycho-existential suffering, compared with those only for physical symptoms, were likely to have no specific religion (p = 0.025), and desired (78.6% vs. 22.0%, respectively; p < 0.001) and requested a hastened death more frequently (57.1% vs. 10.0%, respectively; p < 0.001). All of them had a poor physical condition with limited estimated survival, and mostly (71%) received intermittent sedation before CDS. CDS for psycho-existential suffering caused greater physicians' discomfort (p = 0.037), and lasted for longer (p = 0.029). Dependency, loss of autonomy, and hopelessness were common reasons for psycho-existential suffering that required CDS. The survival time after CDS initiation was longer in patients receiving it for psycho-existential suffering (log-rank, p = 0.021). Conclusion: CDS was applied to patients who suffered from psycho-existential suffering, which often associated with desire or request for a hastened death. Further studies and debate are warranted to develop feasible treatment strategies for psycho-existential suffering.

PEDF-derived peptide inhibits corneal angiogenesis by suppressing VEGF expression.

Pigment epithelium-derived factor (PEDF) a glycoprotein that belongs to the superfamily of serine protease inhibitors, has been recently shown to be the most potent inhibitor of angiogenesis in the mammalian eye. However, which active domain of PEDF protein could be involved in its anti-angiogenic properties remains unknown. Therefore, in this study, we examined which PEDF-derived synthetic peptides could inhibit corneal neovascularization induced by chemical cauterization in vivo. Rats treated with topical application of PEDF protein had 31% less corneal neovascularization at day 7 after the injury than phosphate-buffered saline (PBS)-treated rats. P5-2 and P5-3 peptides (residues 388-393 and 394-400 of PEDF protein, respectively) significantly suppressed the corneal neovascularization after chemical cauterization at day 7, and its anti-angiogenic potential was almost equal to that of full-length PEDF protein. Further, full-length PEDF protein and P5-3 peptide significantly decreased 8-hydroxy-2'-deoxyguanosine and vascular endothelial growth factor (VEGF) levels in the corneal. Our present study suggests that PEDF-derived synthetic peptide, P5-3 could inhibit the corneal neovascularization induced by chemical cauterization in rats by suppressing VEGF expression via its anti-oxidative properties.

Glucagon-like peptide-1 inhibits angiotensin II-induced mesangial cell damage via protein kinase A.

There is a growing body of evidence that renin-angiotensin system plays a role in diabetic nephropathy. Recently, we have found that glucagon-like peptide-1 (GLP-1), one of the incretins, a gut hormone secreted from L cells in the intestine in response to food intake, inhibits advanced glycation end product-induced monocyte chemoattractant protein-1 gene expression in mesangial cells thorugh the interaction with the receptor of GLP-1. However, effects of GLP-1 on angiotensin II-exposed mesangial cells are unknown. This study investigated whether and how GLP-1 blocked the angiotensin II-induced mesangial cell damage in vitro. GLP-1 completely blocked the angiotensin II-induced superoxide generation, NF-κB activation, up-regulation of mRNA levels of intercellular adhesion molecule-1 and plasminogen activator inhibitor-1 in mesangial cells, all of which were prevented by the treatments with H-89, an inhibitor of protein kinase A. The present results demonstrated for the first time that GLP-1 blocked the angiotensin II-induced mesangial cell injury by inhibiting superoxide-mediated NF-κB activation via protein kinase C pathway. Our present study suggests that strategies to enhance the biological actions of GLP-1 may be a promising strategy for the treatment of diabetic nephropathy.