Status of the Newborn Hearing Screening in the 4-Months Age National Infant Health Checkup in Korea: A Nationwide Population-Based Study.

BACKGROUND: The aims of this study are to review data on 4-months age National Health Screening Program for Infants and Children (NHSPIC) using a National Health Insurance Service (NHIS) database, and to analyze the newborn hearing screening (NHS) results and related characteristics of the 4-months NHSPIC for 7 years in South Korea. METHODS: We analyzed a NHIS database of infants who had participated in the 4-month age NHSPIC from 2010 to 2016. According to the results of hearing questionnaires and physical examination, we analyzed the outcomes of NHS and related infantile and socioeconomic factors. RESULTS: Among 3,128,924 of total eligible infants in Korea between the year 2010 and 2016, 69.2% (2,164,621 infants) conducted 4-months age NHSPIC, and 94.4% (2,042,577 infants) of which performed hearing questionnaires regarding NHS. Among the total hearing examinees, premature infants accounted for 3.6%, infants who were hospitalized in the neonatal intensive care unit (NICU) for more than 5 days accounted for 5.6%, and infants with head and neck abnormalities were 0.6%. The NHS performing rate was 79.1% for total hearing examinees in 2010, but gradually increased to 88.9% in 2016. The NHS performing rate in 2016 was 93.4% for premature infants, 91.7% for NICU hospitalized babies. The mean referral rate was 0.6% for total hearing examinees, 1.4% for premature infants, and 2.3% for NICU hospitalized babies. When we analyzed the NHS performing rate and the referral rate according to the household income level, the NHS performing rate of infants in Medical Aid programs was the lowest as 65.6%, and the NHS performing rates in other five levels of NHIS was higher ranging between 85.1% to 86.0%. The referral rate of infants in the Medical Aid program (3.8%) was significantly higher than those of infants in other classes (1.10-1.25%). CONCLUSION: The estimated overall NHS performing rate in Korea gradually increased and was 88.9% in 2016. The overall referral rate was low as 0.6%, and it was significantly different depending on the infant's health condition and household income levels. We assume that our finding would help to establish policies managing hearing impaired children, and to develop the customized hearing care service programs considering the household economic levels.

Evaluation of a Rapid and Simple Method for Assessing Retinal Vessel Structures in Adult Zebrafish.

The evaluation of retinal vascular structures is important for analyzing various ophthalmic diseases. Conventional trypsin digestion was used for separating retinal vasculatures in mouse, rat, and other animal models; however, the trypsin method alone is technically difficult to perform and has not been reported in zebrafish to date. In this study, we introduced a rapid and convenient method that allows the investigation of fine vessel structures at a cellular level in the relatively intact retinal vasculature of adult zebrafish. Using an anti-ZO-1 antibody, tight junction structures in retinal vessels were examined in detail and several different cell types constituting blood vessels in arterial and capillary areas were identified. In addition, using cell type-specific antibodies, we identified smooth muscle cells, blood cells, and endothelial cells in the retinal vasculature. Finally, using the hyperglycemic model, we observed the dilation of retinal vessels, the downregulation of tight junction proteins, and the reduction in smooth muscle cells. Based on these results, we provide a rapid and convenient method for the study of retinal vasculature disease in the zebrafish animal model.

Synthesis and Cytotoxicity Studies of Bioactive Benzofurans from Lavandula agustifolia and Modified Synthesis of Ailanthoidol, Homoegonol, and Egonol.

2-Aryl/alkylbenzofurans, which constitute an important subclass of naturally occurring lignans and neolignans, have attracted extensive synthetic efforts due to their useful biological activities and significant pharmacological potential. Herein, we report a general and efficient approach to divergent 2-arylbenzofurans through a one-pot synthesis of versatile 2-bromobenzofurans as key intermediates. Using this approach, the first total synthesis of a series of trisubstituted and tetrasubstituted benzofurans bearing the hydroxyethyl unit, including the natural compounds isolated from Lavandula agustifolia (1-3) and their non-natural derivatives (4-8), was accomplished. We also report a modified synthesis of ailanthoidol, homoegonol, and egonol that enables the divergent synthesis of their derivatives for future exploration. Among these, the representative phenolic natural compound 2 and its derivatives 7 and 5 induced apoptotic cell death related poly(ADP-ribose) polymerase (PARP) cleavage in MCF74, A549, PC3, HepG2, and Hep3B cancer cell lines. Additionally, the tumor suppressor protein p53 was also induced in p53 wild type cancer cells.

Osteomeles schwerinae Extract and Its Major Compounds Inhibit Methylglyoxal-Induced Apoptosis in Human Retinal Pigment Epithelial Cells.

The accumulation and formation of advanced glycation end products (AGEs) are related to diabetes and age-related disease. Osteomeles schwerinae C. K. Schneid. (Rosaceae, OSSC) is used traditionally for the treatment of various diseases in Asia. Previous studies have shown that OSSC elicits preventive effects in an in vivo model of diabetes. This study was to evaluate the antiapoptotic effects of dried leaves and twigs of OSSC extract and its major compounds in ARPE-19 cells-spontaneously arising human retinal pigment epithelial cells-under diabetic conditions. To examine the effects of an OSSC extract and its active compounds (acetylvitexin, hyperoside and quercitrin) on apoptosis in methylglyoxal (MG, the active precursor in the formation of AGEs)-treated ARPE-19 cells and the mechanism by which these effects occur, apoptosis was measured using flow cytometry analysis. Protein expression levels of phospho-p53 (p-p53), Bax and Bcl-2 were determined by western blot analyses. The OSSC extract inhibited apoptosis in MG-treated ARPE-19 cells in a dose-dependent manner. The major compounds also reduced the rate of apoptosis. Both the extract and major compounds also inhibited the expression of p-p53 and Bax and increased the levels of Bcl-2 that had been previously reduced by MG treatment. The OSSC extract (0.1 µg/mL) and its major compounds (0.01 µM) attenuated apoptosis in ARPE-19 cells under toxic diabetic conditions by downregulating of expression of p-p53 and Bax. OSSC may serve as an alternative therapy to retard the development of diabetic retinopathy.

Anti-angiogenic effect of EGHB010, a standardized herbal formula of Paeoniae radix and Glycyrrhizae radix.

EGHB010 is a standardized herbal formula of the rhizome mixture of Paeonia lactiflora Pallas and Glycyrrhiza uralensis Fisch. Neovascularization in the retina is a common pathophysiology of diabetic retinal microvasculopathy and exudative macular degeneration. In this study, we evaluated the inhibitory effects of EGHB010 on abnormal retinal angiogenesis in a hyperoxia-induced neovascular retinopathy model. Vascular endothelial growth factor (VEGF)-mediated vascular tube formation was assayed in human umbilical vascular endothelial cells (HUVECs). Experimental angiogenesis in the retinas was induced by exposing C57BL/6 pups to hyperoxic environment (75% oxygen) on postnatal day 7 (P7) and then returning them to normal oxygen pressure on P12. EGHB010 (50 and 100 mg/kg/day) was administered intraperitoneally for 5 days (P12 - P16). Retinal flat mounts were prepared to measure the extent of retinal neovascularization on P17. The incubation of HUVECs with EGHB010 (1-25 µg/mL) resulted in the inhibition of VEGF-mediated tube formation in a dose-dependent manner. EGHB010 at doses of 50 and 100 mg/kg/day inhibited the formation of retinal neovascular tufts by 31.15±2.28% and 59.83±2.92%, respectively. Together, our results indicate that EGHB010 is a potent anti-angiogenic agent and may have potential for the control of abnormal retinal vessel growth in patients with ischemic retinopathy.

Apricot Kernel Extract and Amygdalin Inhibit Urban Particulate Matter-Induced Keratoconjunctivitis Sicca.

Exposure to particulate matter is a risk factor for various ocular surface diseases, including keratoconjunctivitis sicca (KCS). In this study, we investigated the protective effects of apricot kernel extract (AKE) and its bioactive compound, amygdalin, on KCS induced by exposure to urban particulate matter (UPM). In the in vivo experiments, eye drops containing 0.5 mg/mL AKE (AKE-0.5) or 1 mg/mL AKE (AKE-1) were administered directly into the eyes of female rats after UPM exposure. Additionally, the effect of AKE and amygdalin on matrix metalloproteinases (MMPs) activity and the expressions of inflammatory factors, including tumor necrosis factor (TNF)-α and interleukin (IL)-6, was investigated in conjunctival epithelial cells in vitro. Topical administration of AKE-1 attenuated UPM exposure-induced reduction of tear secretion. Both AKE-0.5 and AKE-1 inhibited UPM exposure-induced corneal epithelial damage and irregularity. AKE also protected against UPM exposure-induced disruption of the mucin-4 layer on the ocular surface. In addition, AKE and amygdalin prevented UPM-induced activation of MMPs and upregulation of TNF-α and IL-6 in conjunctival epithelial cells. Therefore, AKE may have protective effects against UPM exposure-induced KCS via the inhibition of MMPs and inflammation. The pharmacological activities of AKE may be in part due to its bioactive compound, amygdalin.

Polyphenols from Euphorbia pekinensis Inhibit AGEs Formation In Vitro and Vessel Dilation in Larval Zebrafish In Vivo.

To identify active compounds in the roots of Euphorbia pekinensis for treatment of diabetic complications, an active column fraction from a 70% EtOH extract of E. pekinensis root was purified by preparative reversed-phase high-performance liquid chromatography, leading to the isolation of a new ellagic acid derivative, 3,3'-di-O-methylellagic acid 4-O-(6"-O-galloyl)-ß-D-galactopyranoside (1: ), along with three known compounds, geraniin (2: ), 3,3'-di-O-methylellagic acid 4-O-ß-D-xylopyranoside (3: ), and ellagic acid 3,3'-dimethyl ether (4: ). The structure of the new compound was established by extensive spectroscopic studies and chemical evidence. The inhibitory effects of isolated compounds 1: -4: on advanced glycation end-products (AGEs) formation were examined. All compounds exhibited considerable inhibition of AGEs formation and IC50 values of 0.41 - 12.33 µM, compared with those of the positive controls aminoguanidine (IC50 = 1122.34 µM) and quercetin (IC50 = 27.80 µM). In addition, the effects of 2: and 4: on the dilation of hyaloid-retinal vessels induced by high glucose (HG) in larval zebrafish were investigated; both compounds significantly reduced the HG-induced dilation of hyaloid-retinal vessels relative to the HG-treated control group.

Rational modification of substrate binding site by structure-based engineering of a cellobiose 2-epimerase in Caldicellulosiruptor saccharolyticus.

BACKGROUND: Lactulose, a synthetic disaccharide, has received increasing interest due to its role as a prebiotic, specifically proliferating Bifidobacilli and Lactobacilli and enhancing absorption of calcium and magnesium. The use of cellobiose 2-epimerase (CE) is considered an interesting alternative for industrial production of lactulose. CE reversibly converts D-glucose residues into D-mannose residues at the reducing end of unmodified ß-1,4-linked oligosaccharides, including ß-1,4-mannobiose, cellobiose, and lactose. Recently, a few CE 3D structure were reported, revealing mechanistic details. Using this information, we redesigned the substrate binding site of CE to extend its activity from epimerization to isomerization. RESULTS: Using superimposition with 3 known CE structure models, we identified 2 residues (Tyr114, Asn184) that appeared to play an important role in binding epilactose. We modified these residues, which interact with C2 of the mannose moiety, to prevent epimerization to epilactose. We found a Y114E mutation led to increased release of a by-product, lactulose, at 65 °C, while its activity was low at 37 °C. Notably, this phenomenon was observed only at high temperature and more reliably when the substrate was increased. Using Y114E, isomerization of lactose to lactulose was investigated under optimized conditions, resulting in 86.9 g/l of lactulose and 4.6 g/l of epilactose for 2 h when 200 g/l of lactose was used. CONCLUSION: These results showed that the Y114E mutation increased isomerization of lactose, while decreasing the epimerization of lactose. Thus, a subtle modification of the active site pocket could extend its native activity from epimerization to isomerization without significantly impairing substrate binding. While additional studies are required to scale this to an industrial process, we demonstrated the potential of engineering this enzyme based on structural analysis.

Flavonoids from Litsea japonica Inhibit AGEs Formation and Rat Lense Aldose Reductase In Vitro and Vessel Dilation in Zebrafish.

In our ongoing efforts to identify effective naturally sourced agents for the treating of diabetic complications, two new (1 and 2) and 11 known phenolic compounds (3-13) were isolated from an 80 % ethanol extract of Litsea japonica leaves. The structures of the new compounds were established by spectroscopic and chemical studies. These isolates (1-13) were subjected to an in vitro bioassay evaluating their inhibitory activity on advanced glycation end products formation and rat lens aldose reductase activity. Of the compounds evaluated, the flavonoids (3, 4, 6-8, 11, and 12) markedly inhibited advanced glycation end products formation, with IC50 values of 7.4-72.0 µM, compared with the positive control, aminoguanidine (IC50 = 975.9 µM). In the rat lens aldose reductase assay, consistent with the inhibition of advanced glycation end products formation, the flavonoids (3, 4, 6-8, 11, and 12) exhibited considerable inhibition of rat lens aldose reductase activity, with IC50 values of 1.1-12.5 µM. In addition, the effects of kaempferol (4) and tiliroside (7) on the dilation of hyaloid-retinal vessels induced by high glucose in larval zebrafish were investigated. Only kaempferol significantly reduced the diameters of high glucose-induced hyaloid-retinal vessels, by 52.2 % at 10 µM, compared with those in the high glucose-treated control group.

Aster koraiensis extract prevents diabetes-induced retinal vascular dysfunction in spontaneously diabetic Torii rats.

BACKGROUND: Aster koraiensis extract (AKE) is a standard dietary herbal supplement. The aim of this study is to investigate the inhibitory effects of AKE on diabetes-induced retinal vascular dysfunction in Spontaneously Diabetic Torii (SDT) rats. METHODS: AKE (50 and 100 mg/kg body weight/day) was administered for 16 weeks. The effects of orally administered AKE on blood glucose levels, retinal vascular leakage, apoptosis, and accumulation of advanced glycation end products (AGEs) in the retina were evaluated. RESULTS: SDT rats exhibited hyperglycemia and retinal vascular leakage, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was clearly detected apoptosis in the retinal microvasculature. Immunofluorescence staining revealed the accumulation of AGEs in the retinal vasculature of the SDT rats. However, oral administration of AKE for 16 weeks blocked diabetes-induced blood-retinal barrier (BRB) breakdown and the loss of occludin, which is an important tight junction protein. Apoptosis of retinal vascular cells and AGE accumulation were significantly inhibited after AKE treatment. CONCLUSION: These results indicate that, as a dietary herbal supplement, AKE may have beneficial effects on patients with diabetic retinopathy.

GS-E3D, a new pectin lyase-modified red ginseng extract, inhibited diabetes-related renal dysfunction in streptozotocin-induced diabetic rats.

BACKGROUND: GS-E3D is a newly developed pectin lyase-modified red ginseng extract. The purpose of this study was to investigate the therapeutic effects of GS-E3D on diabetes-related renal dysfunction in streptozotocin-induced diabetic rats. METHOD: GS-E3D (25, 50, and 100 mg/kg body weight per day) was administered for 6 weeks. The levels of blood glucose and hemoglobin A1c, and of urinary albumin, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and advanced glycation end-products (AGEs) were determined. Kidney histopathology, renal accumulation of AGEs, and expression of α-smooth muscle actin (α-SMA) were also examined. RESULTS: Administration of GS-E3D for 6 weeks reduced urinary levels of albumin, 8-OHdG, and AGEs in diabetic rats. Mesangial expansion, renal accumulation of AGEs, and enhanced α-SMA expression were significantly inhibited by GS-E3D treatment. Oral administration of GS-E3D dose-dependently improved all symptoms of diabetic nephropathy by inhibiting renal accumulation of AGEs and oxidative stress. CONCLUSION: The results of this study indicate that the use of GS-E3D as a food supplement may provide effective treatment of diabetes-induced renal dysfunction.

Cnidium officinale extract and butylidenephthalide inhibits retinal neovascularization in vitro and in vivo.

BACKGROUND: Retinal neovascularization, which is the pathological growth of new blood vessels, is associated with retinopathy of prematurity, neovascular age-related macular degeneration, diabetic retinopathy and retinal vein occlusion. In this study, we evaluated the effect of an extract of Cnidium officinale Makino (COE) and its bioactive compound, butylidenephthalide (BP), on the migration and tube formation of human umbilical vein endothelial cells (HUVECs), and on retinal pathogenic neovascularization in the oxygen-induced retinopathy (OIR) mouse model. METHOD: The HUVECs were incubated with COE and BP (0.1-10 µg/ml). The mice were exposed to 75 % oxygen for 5 days starting on the 7(th) postnatal day (P7-P12). Then, the mice were returned to room air and intraperitoneally injected with COE (100 mg/kg) and BP (5 mg/kg) once per day for 5 days (P12-P16). On P17, we measured retinal neovascularization and analyzed the angiogenesis-related proteins expression using protein arrays. RESULTS: COE and BP inhibit the HUVECs migration and the tube formation in a dose-dependent manner. In addition, COE significantly decreased retinal neovascularization in the OIR mice. COE reduced the expression levels of AREG, ANG, DLL4, Endostatin, IGFBP-2 and VEGF. Additionally, BP also inhibited the retinal neovascularization and down-regulated the expression of AREG, ANG, DLL4 and VEGF. CONCLUSION: These results suggest that COE and BP exerts antiangiogenic effects on retinal neovascularization by inhibiting the expression of AREG, ANG, DLL4 and VEGF, indicating that antiangiogenic activities of COE may be in part due to its bioactive compound, BP.

HL-217, a new topical anti-angiogenic agent, inhibits retinal vascular leakage and pathogenic subretinal neovascularization in Vldlr⁻/⁻ mice.

HL-217 is a new synthetic angiogenesis inhibitor. Platelet derived growth factor (PDGF) is a vasoactive factor and has been implicated in proliferative retinopathies. In this study, we examined the mechanism of action and efficacy of topical application of HL-217 on subretinal neovascularization in very low-density lipoprotein receptor knockout (Vldlr(-/-)) mice. In three-week-old male Vldlr(-/-) mice, HL-217 (1.5 or 3mg/ml) was administered twice per day for 4 weeks by topical eye drop instillation. Neovascular areas were then measured. We used a protein array to evaluate the expression levels of angiogenic factors. The inhibitory effect of HL-217 on the PDGF-BB/PDGFRß interaction was evaluated in vitro. The neovascular area in the Vldlr(-/-) mice was significantly reduced by HL-217. Additionally, HL-217 decreased the expression levels of PDGF-BB protein and VEGF mRNA. Moreover, HL-217 dose-dependently inhibited the PDGF-BB/PDGFRß interaction (IC50=38.9 ± 0.7 µM). These results suggest that HL-217 is a potent inhibitor of PDGF-BB. HL-217, when applied topically, is an effective inhibitor of subretinal neovascularization due to its ability to inhibit the pro-angiogenic effects of PDGF-BB.

Development of a Novel Plasmid-Free Thymidine Producer by Reprogramming Nucleotide Metabolic Pathways.

A novel thymidine-producing strain of Escherichia coli was prepared by genome recombineering. Eleven genes were deleted by replacement with an expression cassette, and 7 genes were integrated into the genome. The resulting strain, E. coli HLT013, showed a high thymidine yield with a low deoxyuridine content. DNA microarrays were then used to compare the gene expression profiles of HLT013 and its isogenic parent strain. Based on microarray analysis, the pyr biosynthesis genes and 10 additional genes were selected and then expressed in HLT013 to find reasonable candidates for enhancing thymidine yield. Among these, phage shock protein A (PspA) showed positive effects on thymidine production by diminishing redox stress. Thus, we integrated pspA into the HLT013 genome, resulting in E. coli strain HLT026, which produced 13.2 g/liter thymidine for 120 h with fed-batch fermentation. Here, we also provide a basis for new testable hypotheses regarding the enhancement of thymidine productivity and the attainment of a more complete understanding of nucleotide metabolism in bacteria.

Deoxycytidine production by a metabolically engineered Escherichia coli strain.

BACKGROUND: Rational engineering studies for deoxycytidine production were initiated due to low intracellular levels and tight regulation. To achieve high-level production of deoxycytidine, a useful precursor of decitabine, genes related to feed-back inhibition as well as the biosynthetic pathway were engineered. Additionally, we predicted the impact of individual gene expression levels on a complex metabolic network by microarray analysis. Based on these findings, we demonstrated rational metabolic engineering strategies capable of producing deoxycytidine. RESULTS: To prepare the deoxycytidine producing strain, we first deleted 3 degradation enzymes in the salvage pathway (deoA, udp, and deoD) and 4 enzymes involved in the branching pathway (dcd, cdd, codA and thyA) to completely eliminate degradation of deoxycytidine. Second, purR, pepA and argR were knocked out to prevent feedback inhibition of CarAB. Third, to enhance influx to deoxycytidine, we investigated combinatorial expression of pyrG, T4 nrdCAB and yfbR. The best strain carried pETGY (pyrG-yfbR) from the possible combinatorial plasmids. The resulting strain showed high deoxycytidine yield (650 mg/L) but co-produced byproducts. To further improve deoxycytidine yield and reduce byproduct formation, pgi was disrupted to generate a sufficient supply of NADPH and ribose. Overall, in shake-flask cultures, the resulting strain produced 967 mg/L of dCyd with decreased byproducts. CONCLUSIONS: We demonstrated that deoxycytidine could be readily achieved by recombineering with biosynthetic genes and regulatory genes, which appeared to enhance the supply of precursors for synthesis of carbamoyl phosphate, based on transcriptome analysis. In addition, we showed that carbon flux rerouting, by disrupting pgi, efficiently improved deoxycytidine yield and decreased byproduct content.

Phenolic Compounds from the Leaves and Twigs of Osteomeles schwerinae That Inhibit Rat Lens Aldose Reductase and Vessel Dilation in Zebrafish Larvae.

Three new phenolic biphenyl derivatives (1-3) and one new lignan glycoside (4) were isolated from the leaves and twigs of Osteomeles schwerinae. The structures of the new compounds were established by spectroscopic data interpretation. The inhibitory effects of 1-4 on rat lens aldose reductase in vitro were examined, and compounds 1-3 markedly inhibited the enzyme with IC50 values of 3.8 to 13.8 µM. In addition, the effects of these isolates on the dilation of hyaloid-retinal vessels induced by high glucose (HG) in zebrafish larvae were investigated. Compound 1 was the most effective in reducing HG-induced dilation of hyaloid-retinal vessels.

Lignans from the stems and leaves of Brandisia hancei and their effects on VEGF-induced vascular permeability and migration of HRECs and DLAV formation in zebrafish.

In our continuing search for novel antiangiogenic agents, a new lignan glycoside, (7R,8R)-1-(4-O-ß-d-glucopyranosyl-3-methoxyphenyl)-2-{2-methoxy-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (1), along with three known lignans (2-4), were isolated from the 80% EtOH extract of Brandisia hancei stems and leaves. These isolates (1-4) were subjected to an in vitro bioassay to evaluate their effects on vascular endothelial growth factor (VEGF)-induced vascular permeability and migration of human retinal endothelial cells (HRECs). Of the compounds tested, compound 1 resulted in the greatest reduction in VEGF-induced vascular permeability by about 31.5% at 10 µM compared to the VEGF-treated control. In the migration assay, compounds 1 and 2 significantly decreased VEGF-induced HREC migration. Furthermore, zebrafish embryos treated with compounds 1 and 2 showed mild reductions of dorsal longitudinal anastomotic vessel (DLAV) formation.

Hyperpigmentation mechanism of methyl 3,5-di-caffeoylquinate through activation of p38 and MITF induction of tyrosinase.

Methyl 3,5-di-caffeoylquinate (3,5-diCQM) has been used for the treatment of various diseases in oriental medicine, but its effect on melanogenesis has not been reported yet. In this study, the molecular mechanism of 3,5-diCQM-induced melanogenesis was investigated. It was found that 3,5-diCQM induced synthesis of melanin pigments in murine B16F10 melanoma cells in a concentration-dependent manner. Treatment of cells with 3,5-diCQM for 48 h increased extracellular and intracellular melanin production and tyrosinase activity. The expressions of tyrosinase, tyrosinase-related protein 1 (TRP1), and TRP2 were up-regulated in a dose-dependent manner 48 h after 3,5-diCQM treatment. Western blot analysis showed that 3,5-diCQM increased the phosphorylation of p38 mitogen-activated protein kinase and cAMP responsive element binding as well as the expression of microphthalmia-associated transcription factor. In addition, 3,5-diCQM-stimulated cAMP production, and 3,5-diCQM-induced tyrosinase activity and melanin synthesis were attenuated by H89, a protein kinase A inhibitor. These results suggested that 3,5-diCQM-mediated activation of the p38 pathway may represent a novel approach for an effective therapy for vitiligo and hair graying.

Inhibitory effect of Samul-tang on retinal neovascularization in oxygen-induced retinopathy.

BACKGROUND: Retinal neovascularization is a common cause of vision loss in proliferative diabetic retinopathy, retinopathy of prematurity and age-related macular degeneration. Samul-tang (SMT) is a widely used traditional herbal medicine in East Asia and is also known as Shimotsu-to in Japanese and Si-Wu decoction in Chinese. This study was designed to evaluate the inhibitory effect of SMT on retinal pathogenic angiogenesis in a mouse model of oxygen-induced retinopathy (OIR). METHOD: The mice were exposed to a 75% concentration of oxygen for five days, starting on postnatal day 7 (P7-P12). The mice were then exposed to room air and were intraperitoneally injected with SMT (10 mg/kg or 50 mg/kg) once per day for five days (P12-P16). On P17, we measured retinal neovascularization and evaluated both the expression of angiogenesis-related proteins and changes in the gene expression level in the mRNA. RESULTS: SMT reduced the area of the central retina and reduced retinal neovascularization in OIR mice. The protein array revealed that SMT reduced the level of SDF-1 protein expression. Quantitative real-time PCR revealed that the HIF-1α, SDF-1, CXCR4 and VEGF mRNA levels in the retinas of OIR mice were elevated compared with those of normal control mice. However, SMT decreased the levels of HIF-1α, SDF-1, CXCR4 and VEGF mRNA in OIR mice. CONCLUSION: We are the first to elucidate that SMT inhibits the retinal pathogenic angiogenesis induced by ischemic retinopathy in OIR mice. SMT significantly inhibited retinal neovascularization by downregulating HIF-1α, SDF-1, CXCR4 and VEGF. Based on the results of our study, SMT could be a useful herbal medicine for treating ischemic retinopathy.

Geranylated flavanones from Paulownia coreana and their inhibitory effects on nitric oxide production.

The activity-guided fractionation of the MeOH extract of the flower of Paulownia coreana led to the isolation of a new geranylated flavanone, 3'-O-methyl-5'-hydroxydiplacol (1), along with 10 known compounds (2-11). Their structures were determined using spectroscopic techniques, which included one and two dimensional (1- and 2D)-NMR. Among the isolates, compounds 1-6 showed potent inhibitory activities against lipopolysaccharide (LPS)-induced nitric oxide production with IC50 values ranging 1.48 to 16.66 µM.