Background:Overexpression of inducible nitric oxide synthase(iNOS)has been reported in diabetic retinopathy(DR).The kinin B1 receptor(B1R)is also overexpressed in DR,and can stimulate iNOS via Gαi/ERK/MAPK pathway.We...Background:Overexpression of inducible nitric oxide synthase(iNOS)has been reported in diabetic retinopathy(DR).The kinin B1 receptor(B1R)is also overexpressed in DR,and can stimulate iNOS via Gαi/ERK/MAPK pathway.We previously showed that the topical administration of a B1R antagonist,LF22-0542,significantly reduces leukocyte infiltration,increased vascular permeability and overexpression of several inflammatory mediators,including iNOS in DR.Thus,the aim of this study was to determine whether the pro-inflammatory effects of B1R are attributed to oxidative stress caused by the activation of iNOS pathway in order to identify new therapeutic targets for the treatment of DR.iNOS and B1R being absent in the normal retina,their inhibition is unlikely to result in undesirable side effects.The approach will be no invasive by eye application of drops.Methods:Diabetes was induced in male Wistar rats(200-230 g)by a single intraperitoneal injection of streptozotocin(STZ,65 mg/kg b.w).One week later,rats were randomly divided into four groups(N=5)and treated for one week as follows:Gr 1:control rats treated with the selective iNOS inhibitor(1,400 W,0.06μM twice a day by eye-drops×7 days),Gr 2,STZ-diabetic rats treated with 1,400 W,Gr 3:control rats received a selective B1R agonist[Sar(D-Phe8)-des-Arg9-BK,100μg twice a week]by intravitreal injections(itrv)and treated with 1,400 W,Gr 4:STZ-diabetic rats+B1R agonist+1,400 W.At the end of treatment and two weeks post-STZ,three series of experiments were carried out to measure vascular permeability(by Evans blue dye method)and the expression of vasoactive and inflammatory mediators,including iNOS,VEGF-A,VEGF-R2,IL-1β,Cox-2,TNF-α,bradykinin 1 and 2 receptors and carboxypeptidase M/kininase 1(by Western Blotting and qRT-PCR).The nitrosative stress(nitrosylation of proteins)was also assessed by Western Blotting.One-way Anova test with Bonferroni post hoc was used for statistical analysis.Results:STZ-diabetic rats showed a significant increase in retinal vascular permeability(22.8μg/g Evans blue dye per g of fresh retinas,P=0.016)compared with control rats and control treated rats(17.2 and 16.8μg/g respectively).The injections of B1R agonist amplified the increase of vascular permeability which was normalized by the 1,400 W.The overexpression of inflammatory markers was also normalized by the 1,400 W in STZ-diabetic rats received or not the B1R agonist.Conclusions:These results support a contribution of iNOS in the deleterious effects of B1R in this model of diabetic retinopathy.Hence,iNOS inhibition by ocular application of 1,400 W may represent a promising and non-invasive therapeutic approach in the treatment of diabetic retinopathy.展开更多
Despite tremendous strides in modern medicine stringent control over insulin resistance or restoration of normoglycemia has not yet been achieved.With the growth of molecular biology,omics technologies,docking studies...Despite tremendous strides in modern medicine stringent control over insulin resistance or restoration of normoglycemia has not yet been achieved.With the growth of molecular biology,omics technologies,docking studies,and in silico pharmacology,modulators of enzymes and receptors affecting the molecular pathogenesis of the disease are being considered as the latest targets for anti-diabetic therapy.Therapeutic molecular targets are now being developed basing on the up or down regulation of different signaling pathways affecting the disease.Phytosynergistic antidiabetic therapy is in vogue both with classical and non-classical medicinal systems.However its chemoprofiling,structural and pharmacokinetic validation awaits providing recognition to such formulations for international acceptance.Translational health research with its focus on benchside product development and its sequential transition to patient bedside puts the pharma RDs to a challenge to develop bio-waiver protocols.Pharmacokinetic simulation models and establishment of in vitro-in vivo correlation can help to replace in vivo bioavailability studies and provide means of quality control for scale up and post approval modification.Thisreview attempts to bring different shades highlighting phyto-synergy,molecular targeting of antidiabetic agents via different signaling pathways and bio-waiver studies under a single umbrella.展开更多
目的探讨大黄游离蒽醌(free anthraquinone from rhubarb,FAR)对糖尿病大鼠心肌CTGF和collagen表达及间质纤维化的影响。方法健康♂SD大鼠一次性腹腔注射STZ制备糖尿病大鼠模型,2周后随机分为模型对照组(DCM组)和大黄游离蒽醌干预组(FAR...目的探讨大黄游离蒽醌(free anthraquinone from rhubarb,FAR)对糖尿病大鼠心肌CTGF和collagen表达及间质纤维化的影响。方法健康♂SD大鼠一次性腹腔注射STZ制备糖尿病大鼠模型,2周后随机分为模型对照组(DCM组)和大黄游离蒽醌干预组(FAR组),同时设立正常对照组(CON组);干预8周后检测大鼠空腹血糖;心脏质量指数;Masson染色观察心肌纤维化程度;RT-PCR法检测CTGF、procollagenⅠ和collagenⅢmRNA表达;免疫组化法检测CTGF蛋白含量;ELISA法检测collagenⅠ和collagenⅢ胶原含量。结果与CON组相比,DCM组大鼠空腹血糖、心脏质量指数、心肌纤维化程度以及CTGF、collagen I和collagenⅢ表达均明显升高;与DCM相比,FAR组心脏质量指数、心肌纤维化程度以及CTGF、collagenⅠ和collagenⅢ表达均明显下降。结论大黄游离蒽醌可通过调低糖尿病大鼠心肌组织CTGF的表达,减少心肌间质中collagen I和Ⅲ合成及沉积。展开更多
玻璃体切除术(pars plana vitrectomy,PPV)为增殖性糖尿病视网膜病变(proliferative diabeticretinopathy,PDR)常用治疗手段,但手术难度大、出血量多,难以有效控制,会延长手术时间、增加手术失败风险。采取有效措施优化治疗,降低手术风...玻璃体切除术(pars plana vitrectomy,PPV)为增殖性糖尿病视网膜病变(proliferative diabeticretinopathy,PDR)常用治疗手段,但手术难度大、出血量多,难以有效控制,会延长手术时间、增加手术失败风险。采取有效措施优化治疗,降低手术风险是近年来的研究热点。展开更多
文摘Background:Overexpression of inducible nitric oxide synthase(iNOS)has been reported in diabetic retinopathy(DR).The kinin B1 receptor(B1R)is also overexpressed in DR,and can stimulate iNOS via Gαi/ERK/MAPK pathway.We previously showed that the topical administration of a B1R antagonist,LF22-0542,significantly reduces leukocyte infiltration,increased vascular permeability and overexpression of several inflammatory mediators,including iNOS in DR.Thus,the aim of this study was to determine whether the pro-inflammatory effects of B1R are attributed to oxidative stress caused by the activation of iNOS pathway in order to identify new therapeutic targets for the treatment of DR.iNOS and B1R being absent in the normal retina,their inhibition is unlikely to result in undesirable side effects.The approach will be no invasive by eye application of drops.Methods:Diabetes was induced in male Wistar rats(200-230 g)by a single intraperitoneal injection of streptozotocin(STZ,65 mg/kg b.w).One week later,rats were randomly divided into four groups(N=5)and treated for one week as follows:Gr 1:control rats treated with the selective iNOS inhibitor(1,400 W,0.06μM twice a day by eye-drops×7 days),Gr 2,STZ-diabetic rats treated with 1,400 W,Gr 3:control rats received a selective B1R agonist[Sar(D-Phe8)-des-Arg9-BK,100μg twice a week]by intravitreal injections(itrv)and treated with 1,400 W,Gr 4:STZ-diabetic rats+B1R agonist+1,400 W.At the end of treatment and two weeks post-STZ,three series of experiments were carried out to measure vascular permeability(by Evans blue dye method)and the expression of vasoactive and inflammatory mediators,including iNOS,VEGF-A,VEGF-R2,IL-1β,Cox-2,TNF-α,bradykinin 1 and 2 receptors and carboxypeptidase M/kininase 1(by Western Blotting and qRT-PCR).The nitrosative stress(nitrosylation of proteins)was also assessed by Western Blotting.One-way Anova test with Bonferroni post hoc was used for statistical analysis.Results:STZ-diabetic rats showed a significant increase in retinal vascular permeability(22.8μg/g Evans blue dye per g of fresh retinas,P=0.016)compared with control rats and control treated rats(17.2 and 16.8μg/g respectively).The injections of B1R agonist amplified the increase of vascular permeability which was normalized by the 1,400 W.The overexpression of inflammatory markers was also normalized by the 1,400 W in STZ-diabetic rats received or not the B1R agonist.Conclusions:These results support a contribution of iNOS in the deleterious effects of B1R in this model of diabetic retinopathy.Hence,iNOS inhibition by ocular application of 1,400 W may represent a promising and non-invasive therapeutic approach in the treatment of diabetic retinopathy.
文摘Despite tremendous strides in modern medicine stringent control over insulin resistance or restoration of normoglycemia has not yet been achieved.With the growth of molecular biology,omics technologies,docking studies,and in silico pharmacology,modulators of enzymes and receptors affecting the molecular pathogenesis of the disease are being considered as the latest targets for anti-diabetic therapy.Therapeutic molecular targets are now being developed basing on the up or down regulation of different signaling pathways affecting the disease.Phytosynergistic antidiabetic therapy is in vogue both with classical and non-classical medicinal systems.However its chemoprofiling,structural and pharmacokinetic validation awaits providing recognition to such formulations for international acceptance.Translational health research with its focus on benchside product development and its sequential transition to patient bedside puts the pharma RDs to a challenge to develop bio-waiver protocols.Pharmacokinetic simulation models and establishment of in vitro-in vivo correlation can help to replace in vivo bioavailability studies and provide means of quality control for scale up and post approval modification.Thisreview attempts to bring different shades highlighting phyto-synergy,molecular targeting of antidiabetic agents via different signaling pathways and bio-waiver studies under a single umbrella.
文摘玻璃体切除术(pars plana vitrectomy,PPV)为增殖性糖尿病视网膜病变(proliferative diabeticretinopathy,PDR)常用治疗手段,但手术难度大、出血量多,难以有效控制,会延长手术时间、增加手术失败风险。采取有效措施优化治疗,降低手术风险是近年来的研究热点。
