PDE4 inhibition protects against rotenone-induced neurotoxicity through activation of the AMPK/Sirt1 pathway / 中国药理学与毒理学杂志

OBJECTIVE We have previously shown that inhibition of phosphodiesterase-4(PDE4)protects against neuronal damage in models of Parkinson's dis-ease(PD).However,the mechanisms have not yet been completely revealed.Here we aimed to elucidate the pharmacological effects and mechanisms of action of rof-lupram(ROF),an novel PDE4 inhibitor,in experimen-tal models of PD.METHODS The survival rate,apopto-sis rate and toxicity level of SH-SY5Y cells were deter-mined by MTT,flow cytometry and lactate dehydroge-nase detection kit.At the same time,LYT staining was used to detect the changes of lysosome fluorescence intensity:Western blotting was used to detect the changes of lysosome associated proteins,Sirtuin1 and α-Syn;NAD/NADH assay kit was used to determine the change of NAD content.To explore whether SIRT1 inhibitor(EX527)and lysosomal inhibitor could block the effect of ROF.In addition,ROT was used to stimulate C57BL/6J mice to construct a mouse model of PD to verify the effect and mechanism of ROF.The changes of motor function were evaluated by behavioral experiments(pole climb-ing,bar rotating and balance beam experiments).Super-oxide dismutase kit and Western blotting were used to detect the changes of SOD activity and expression of related proteins in substantia nigra.RESULTS We showed that pretreatment with ROF significantly attenu-ated cell apoptosis in ROT-treated SH-SY5Y cells.Fur-thermore,ROF significantly enhanced the lysosomal function,as evidenced by the increased levels of mature cathepsin D(CTSD)and lysosomal-associated mem-brane protein 1(LAMP1)through increasing NAD+/NADH and the expression of sirtuin 1(SIRT1).Pretreatment with an SIRT1 inhibitor selisistat(SELI,10 μ mol·L-1)attenuated the neuroprotection of ROF,and ROF-increased expression levels of LAMP1 and mature CTSD.Moreover,inhibition of CTSD by pepstatin A(20 μmol·L-1)attenuated the protective effects of ROF.In vivo study was conducted in mice exposed to ROT(10 mg·kg-1·d-1,ig)for six weeks;then,ROT-treated mice received ROF(0.5,1 and 2 mg·kg-1·d-1,ig)for four weeks.ROF significantly ameliorated motor deficits,which was accompanied by increased expression levels of tyro-sine hydroxylase,SIRT1,mature CTSD,and LAMP1 in the substantia nigra pars compacta.CONCLUSION Taken together,these results demonstrate that ROF exerts a neuroprotective action in PD models.The mech-anisms underlying ROF neuroprotective effects appear to be associated with NAD+/SIRT1-dependent activation of lysosomal function.

Inhibition of phosphodiesterase 4 attenuates aquapo-rin 4 expression and astrocyte swelling following cerebral ischemia/reperfusion injury / 中国药理学与毒理学杂志

OBJECTIVE To investigate the role of PDE4 inhibition in astrocyte swelling caused by cerebral ischemic/reperfusion(I/R)injury and the molecular mech-anisms.METHODS SD rats were subjected to 2 h of focal cerebral ischemia induced by middle cerebral artery occlusion/reperfusion(MCAO/R).Roflumilast(Roflu)was intraperitoneally injected 2 h after MCAO.At 24 h after reperfusion,a high-resolution MRI was performed and using the wet-dry weighting method to measure the water content.The oxygen-glucose deprivation/reoxygenation(OGD/R)model was established in primary astrocytes for 2 h.After 24 h of reoxygenation,CellMask? plasma membrane stain was used to label the plasma membrane to calculate cell volume.The protein expressions insides astrocytes and penumbra were detected by Western blot-ting.To investigate the role of Akt/FoxO3a in mediating the effect of Roflu on the expression of AQP4.The astro-cytes were treated with an Akt inhibitor MK2206 before treatment with Roflu and the activation of Akt,the expres-sion of AQP4 and cell volume were determined as described above.In addition,an IL-1β-stimulated cell model was established in astrocytes,the expression of AQP4 and the activation of Akt/FoxO3a were detected by Western blotting.The change of AQP4 expression inside astrocytes and penumbra were visualized by immunofluo-rescence staining.RESULTS Roflu reduced MCAO/R-induced water contents,the expression of AQP4 and the phsophorylation of Akt and FoxO3a in the brains of MCAO/R rats.Inhibition of PDE4 decreased the cell volume and the expression of AQP4 in primary astro-cytes subjected to OGD/R.PDE4 inhibition activated Akt/FoxO3a,and inhibition of Akt by MK2206 blocked the protective effect of Roflu against OGD/R induced astro-cyte swelling.PDE4B knocking down reduced the expres-sion of AQP4,while PDE4B overexpression reversed the effect of PDE4B siRNA in astrocytes.Roflu exert-ed similar protective effect in IL-1β-cultured astrocytes,and importantly overexpression of FoxO3a remarkably increased the expression of AQP4 in IL-1β-stimulated astrocytes.CONCLUSION Our findings indicate that PDE4 inhibition limits I/R-induced brain edema and astro-cyte swelling via the Akt/FoxO3a/AQP4 pathway.PDE4 inhibition is a promising strategy for the treatment of brain edema after I/R injury.

A clinical study of different doses and frequencies of Sildenafil in the treatment of erectile dysfunction / 现代泌尿外科杂志

【Objective】 To evaluate the efficacy and safety of different doses and frequencies of oral Sildenafil in the treatment of erectile dysfunction (ED). 【Methods】 The randomized,open clinical trial included 120 ED patients who met the inclusion and exclusion criteria. The patients were randomly divided into the following groups:on-schedule (25 mg/day),on-demand (50 mg,taken irregularly half an hour before each sexual life),new regular group (25 mg/day,50 mg more before each sexual life),regular group (100 mg/time,twice/week). All treatments lasted for 8 weeks. The follow-up indexes included the five-item International Index of Erectile Function (IIEF-5),Erection Hardness Scale (EHS) and Sexual Encounter Profile (SEP2/3). The adverse reactions were recorded. 【Results】 The IIEF-5 scores of the four groups were significantly higher than those after baseline treatment (P0.05). In terms of effective rate,at the 16th week,there were significant differences between the on-demand group (10.7%) and new regular group (62.1%),and between the on-demand group (10.7%) and regular group (50.0%) (P<0.001). In terms of EHS, the percentage of grade 4 patients in regular group was significant higher than that in the on-demand group at the 8th week and 16th week (all P<0.05). In terms of positive rate of SEP-3,there was a significant difference between the on-demand group and regular group (P=0.042) at the 16th week. In the course of treatment,there were transient adverse reactions such as headache,blurred vision,stuffy nose and back pain,which did not affect the treatment. 【Conclusion】 All of the four treatment methods of oral sildenafil showed good efficacy. Both regular group and new regular group maintained good clinical efficacy during the follow-up,which is better than that of the on-demand group. The new regular scheme can be used as a new,safe and effective treatment option.

Efficacy and safety of phosphodiesterase type 5 inhibitors and selective serotonin reuptake inhibitors in the treatment of comorbiditiy of erectile dysfunction and premature ejaculation: a meta analysis / 现代泌尿外科杂志

【Objective】 To evaluate the efficacy and safety of phosphodiesterase type 5 (PDE5) inhibitors alone or in combination with selective serotonin reuptake inhibitors (SSRIs) compared with SSRIs alone in the treatment of comorbidity of erectile dysfunction (ED) and premature ejaculation (PE). 【Methods】 The clinical randomized controlled trials of ED and PE comorbidity treated with PDE5 inhibitors alone or in combination with SSRIs were searched from database inception to Sep.2022, in CNKI, PubMed, Web of Science, Embase, Wanfang Database, cqVIP Database, SinoMed and Yiigle. The intravaginal ejaculatory latency time(IELT), score of International Index of Erectile Function 5 (IIEF-5) and adverse reaction rate were analyzed with RevMan 5.4.1 software. 【Results】 A total of9 studies involving 793 patients were included. Meta analysis showed that compared with SSRIs alone, PDE5 inhibitors alone or in combination with SSRIs yielded better results in IELT [MD=1.99, 95%CI(1.51-2.46), P<0.001] and higher IIEF-5 score [MD=4.61, 95%CI(3.68-5.55), P<0.001] , but no increase in adverse events [RR=0.99, 95%CI(0.74-1.31), P=0.92] . 【Conclusion】 In the treatment of ED and PE comorbidity, priority should be given to ED or both ED and PE, which can produce better efficacy without increasing the adverse effects.

The possibility of phosphodiesterase 4 inhibitors as drug therapy for idiopathic pulmonary fibrosis / 中国临床药理学与治疗学

Idiopathic pulmonary fibrosis (IPF) is a progressive, irreversible and typical chronic fibrotic lung disease. In recent years, significant progress has been made in the pathophysiology, clinical diagnosis and treatment of IPF. However, to date, there is still no cure for IPF. The second messenger cyclic adenosine monophosphate (cAMP) inhibits fibroblast proliferation or differentiation into myofibroblasts during the development of IPF. Phosphodiesterase 4 (PDE4) is a major camp-degrading enzyme in lung fibroblasts, which is up-regulated during the progression of fibrosis. PDE4 inhibitors have anti-fibrosis effects in vivo and in vitro in IPF models. In addition, PDE4 is widely involved in inflammatory processes, which are also active in the pathogenesis of IPF. Thus, PDE4 inhibition is a potential therapeutic approach for IPF. This article reviews the pathogenesis of IPF and the physiological function of PDE subtype 4 inhibitors in the treatment of IPF.

Effect of a novel phosphodiesterase type 5 inhibitor, CPD1, on paraquat-induced lung fibrosis in rats / 中国药理学通报

Aim To investigate the effects of CPD1, a novel phosphodiesterase 5 inhibitor, on lung pathological phenotype and epithelial-mesenchymal transition of alveolar epithelial cells in lung fibrosis model rats caused by paraquat (PQ). Methods Lung fibrosis model was constructed by a single intraperitoneal injection of PQ (30 mg·kg

Effect of a novel phosphodiesterase type 5 inhibitor,CPD1,on unilateral renal interstitial fibrosis caused by ureteric obstruction in mice / 中国药理学通报

Aim To investigate the effects of CPD1,a novel phosphodiesterase 5 inhibitor,on renal pathological phenotype and fibrotic protein expression in renal fibrosis model mice. Methods Male C57BL/6 J mice were divided into three groups randomly(sham group,UUO group and UUO+CPD1 group). Unilateral ureteric obstruction model was constructed by surgery,and CPD1(5 mg·kg-1·d-1)was administered by intragastric administration two hours after the modeling for seven days. HE and Sirius Red staining were used to observe the distribution of tissue structural lesions and fibrosis. Immunohistochemical staining and Western blot were used to detect the expression of fibronectin(FN),α-SMA,collagen-I and kidney injury molecule-1(Kim-1). Results Compared with sham operation group,the renal tubules of mice were dilated and accompanied by a large amount of inflammatory infiltration. Moreover,the expressions of FN,α-SMA,collagen-I and Kim-1 proteins increased significantly(P<0.05)in UUO group. CPD1 treatment improved the kidney structure and decreased the expression of collagen fibers. Furthermore,CPD1 inhibited the expression of FN,α-SMA,collagen-I and Kim-1 markedly(P<0.05). Conclusions Phosphodiesterase 5 inhibitor CPD1 alleviates the progression of renal fibrosis induced by unilateral ureteral obstruction through down-regulating ECM deposition in the extracellular matrix and expression of Kim-1. The specific mechanism remains to be further studied.

Effect of a novel phosphodiesterase type 5 inhibitor, CPD1, on carbon tetrachloride-induced liver fibrosis in mice / 中国药理学通报

Aim To investigate the effects of CPD1, a novel phosphodiesterase 5 inhibitor, on liver pathological phenotype and hepatic stellate cells (HSCs) activation in hepatic fibrosis model mice caused by carbon tetrachloride ( CCl

Discovery of novel phosphodiesterase-1 inhibitors for curing vascular dementia: Suppression of neuroinflammation by blocking NF-κB transcription regulation and activating cAMP/CREB axis

Vascular dementia (VaD) is the second commonest type of dementia which lacks of efficient treatments currently. Neuroinflammation as a prominent pathological feature of VaD, is highly involved in the development of VaD. In order to verify the therapeutic potential of PDE1 inhibitors against VaD, the anti-neuroinflammation, memory and cognitive improvement were evaluated in vitro and in vivo by a potent and selective PDE1 inhibitor 4a. Also, the mechanism of 4a in ameliorating neuroinflammation and VaD was systematically explored. Furthermore, to optimize the drug-like properties of 4a, especially for metabolic stability, 15 derivatives were designed and synthesized. As a result, candidate 5f, with a potent IC50 value of 4.5 nmol/L against PDE1C, high selectivity over PDEs, and remarkable metabolic stability, efficiently ameliorated neuron degeneration, cognition and memory impairment in VaD mice model by suppressing NF-κB transcription regulation and activating cAMP/CREB axis. These results further identified PDE1 inhibition could serve as a new therapeutic strategy for treatment of VaD.

Sildenafil in endotoxin-induced pulmonary hypertension: an experimental study

Abstract Background Sepsis and septic shock still represent great challenges in critical care medicine. Sildenafil has been largely used in the treatment of pulmonary arterial hypertension, but its effects in sepsis are unknown. The aim of this study was to investigate the hypothesis that sildenafil can attenuate endotoxin-induced pulmonary hypertension in a porcine model of endotoxemia. Methods Twenty pigs were randomly assigned to Control group (n = 10), which received saline solution; or to Sildenafil group (n = 10), which received sildenafil orally (100 mg). After 30 minutes, both groups were submitted to endotoxemia with intravenous bacterial lipopolysaccharide endotoxin (LPS) infusion (4 µg.kg-1.h-1) for 180 minutes. We evaluated hemodynamic and oxygenation functions, and also lung histology and plasma cytokine (TNFα, IL-1β, IL6, and IL10) and troponin I response. Results Significant hemodynamic alterations were observed after 30 minutes of LPS continuous infusion, mainly in pulmonary arterial pressure (from Baseline 19 ± 2 mmHg to LPS30 52 ± 4 mmHg, p< 0.05). There was also a significant decrease in PaO2/FiO2 (from Baseline 411 ± 29 to LPS180 334 ± 49, p< 0.05). Pulmonary arterial pressure was significantly lower in the Sildenafil group (35 ± 4 mmHg at LPS30, p< 0.05). The Sildenafil group also presented lower values of systemic arterial pressure. Sildenafil maintained oxygenation with higher PaO2/FiO2 and lower oxygen extraction rate than Control group but had no effect on intrapulmonary shunt. All cytokines and troponin increased after LPS infusion in both groups similarly. Conclusion Sildenafil attenuated endotoxin-induced pulmonary hypertension preserving the correct heart function without improving lung lesions or inflammation.

Advances in clinical and safety studies of phosphodiesterase 4 inhibitors / 药学学报

Phosphodiesterase 4 (PDE4) is an important member of the phosphodiesterase enzyme family that specifically catalyzes the hydrolysis of cyclic adenosine monophosphate (cAMP), activates the downstream phosphorylation cascade pathway by altering cAMP concentration, and is strongly associated with multiple diseases. Inhibition of PDE4 is clinically investigated as a therapeutic strategy in a broad range of disease areas, including respiratory system diseases, autoimmune disorders, central nervous system diseases, and dermatological conditions. However, the incidence of adverse reactions such as nausea and vomiting is relatively high in the marketed PDE4 inhibitors, which has stalled their clinical development. In this review, we provide an overview of the clinical progression and safety issues of the marketed PDE4 inhibitors. We also review the main causes underlying PDE4-mediated adverse effects by combining the structural analysis of the PDE4 protein, the mechanism of action of PDE4 inhibitors, and the related side effect mechanism research, aiming to provide a reference for the development of safe and effective PDE4 inhibitors.

Small-molecule targeted agents: new choices for the treatment of psoriasis / 中华皮肤科杂志

With the rapid development of immunology and molecular biology in recent years, great progress has been made in the research on psoriatic pathogenesis, as well as in therapeutic strategies targeting key molecules in the pathogenesis. In addition to biologics, small-molecule targeted agents for psoriasis have also received increasing attention, especially agents targeting phosphodiesterase 4, Janus kinase, and tyrosine kinase 2, etc. An increasing number of small-molecule drug candidates have shown favorable efficacy in clinical studies, and some of them have been approved for clinical application and play a unique role in the treatment of psoriasis.

Advances in the diagnosis of acid sphingomyelinase deficiency / 中国医师杂志

Acid sphingomyelinase deficiency (ASMD), also known as type A and B Niemann-Pick disease, is a group of intra-lysosomal lipid storage diseases caused by mutations in the SMPD1 gene that decrease acid sphingomyelinase activity or even cause deletion, resulting in abnormal deposition of sphingolipids. This disease can be diagnosed by bone marrow aspiration, pathological biopsy, acid sphingomyelinase activity measurement and SMPD1 gene testing. In recent years, with the rapid progress of molecular diagnostic techniques, new insights have been gained in the laboratory diagnosis of ASMD by means of molecular genetic tests, biomarkers and acid sphingomyelinase activity assay. This article will review the diagnostic progress of ASMD, aiming to reduce the misdiagnosis and leakage of the disease and improve the clinicians′ understanding of the disease.

Efficacy and safety of kidney -tonifying Chinese patent medicine combined with PDE 5 inhibitor in the treatment of erectile dysfunction ：a network meta -analysis / 中国药房

OBJECTIVE To systematically review the efficacy and safety of kidney -tonifying Chinese patent medicine combined with phosphodiesterase type 5（PDE5）inhibitors in the treatment of erectile dysfunction （ED），and to provide evidence - based reference for clinical medication . METHODS Retrieved from PubMed ，Embase，Cochrane Library ，Web of Science ，VIP， China Biomedical Literature Database ，CNKI and Wanfang database ，randomized controlled trials （RCTs）of kidney -tonifying Chinese patent medicine combined with PDE 5 inhibitors（trial group ）versus PDE 5 inhibitors or kidney -tonifying Chinese patent medicine alone （control group ）were collected . The search period was from the establishment of the database to February 15，2022. After literature screening and data extraction ，the risk of bias assessment tool recommended in Cochrane System Reviewer ’s Handbook 6.1.0 was used to evaluate the quality of the included literature ；Stata 16.0 software was used for network meta -analysis； and the funnel plot was used for publication bias analysis . RESULTS A total of 23 RCTs were included ，with a total of 2 417 patients， involving 8 kinds of Chinese patent medicines ， including Congrong yishen granule ，Canrong zhutian capsule ， Compound xuanju capsule ， Huanshao capsule ， Shanhaidan granule， Shengjing capsule ， Shisanwei ziyin zhuangyang capsule，Shugan yiyang capsule . The results of network meta analysis showed that in terms of total effective rate ，Compound xuanju capsule combined with PDE 5 inhibitor，Shengjing capsule combined with PDE 5 inhibitor，Shugan yiyang capsule combined with PDE 5 inhibitor had higher total effective rate ；in terms of international index of erectile function 5，the scores of Compound xuanju capsule combined with PDE 5 inhibitor，Congrong yishen granule combined with PDE 5 inhibitor，and Canrong zhutian capsule combined with PDE 5 inhibitor were higher ；in terms of safety ，the incidence of adverse drug reactions caused by Huanshao capsule ，Shanhaidan granule and Shugan yiyang capsule were lower . CONCLUSIONS Kidney-tonifying Chinese patent medicine combined with PDE 5 inhibitor can improve the erectile function of ED patients and reduce the occurrence of adverse drug reactions . In terms of efficacy and safety ，Compound xuanju capsule combined with PDE 5 inhibitor is the best .

Research progress in regulating cAMP pathway to prevent and treat chronic obstructive pulmonary disease / 中国药理学通报

Cyclic adenosine monophosphate(cAMP)is a “second messenger” that regulates cell signal transduction. Adenylyl cyclases(ACs)and phosphodiesterases(PDEs)can directly regulate cAMP level in cells and then regulate the downstream signaling pathways. Increasing intracellular cAMP level can inhibit inflammation and enhance smooth muscle relaxation, which is an effective strategy for the prevention and treatment of chronic obstructive pulmonary disease(COPD). This paper briefly summarizes the signaling pathways regulating cAMP and their mechanisms and related drugs in COPD therapy, hoping to provide references for further research and development of new target drugs which regulate cAMP for the prevention and treatment of COPD.

Establishment of Anti-inflammatory Activity Evaluation Method of Qingjin Huatantang Based on Phosphodiesterase Inhibitory Activity / 中国实验方剂学杂志

ObjectiveBased on the inhibitory activity of phosphodiesterase （PDE）， a method for determining the anti-inflammatory activity of Qingjin Huatantang was established to supplement and improve the quality control system of this famous classical formula. MethodHigh performance liquid chromatography （HPLC） was used to determine the activity of PDE， and the dose-effect relationship of inhibiting PDE activity of Qingjin Huatantang was investigated. The mobile phase consisted of methanol-0.5% acetic acid aqueous solution （5∶95）， and the detection wavelength was 254 nm. By measuring the PDE inhibition rate of multiple batches of Qingjin Huatantang water extract lyophilized powder， biological activity was marked with the activity of the neutralizing enzyme in the international unit U. ResultWhen the concentration of reaction substrate （cyclic adenosine monophosphate） was 50 μmol·L-1 and the reaction time was 60 min， the enzymatic reaction was stable with 4 U·mL-1 of PDE. In this reaction system， when the concentration of Qingjin Huatantang water extract lyophilized powder was 0.11-3.0 g·L-1， the inhibitory effect of PDE showed a concentration-dependent relationship. It was determined that the concentration of Qingjin Huatantang water extract lyophilized powder to be tested was 1 g·L-1， which showed a significant and stable inhibitory effect on PDE， and the inhibitory rate was >45%， that is， 1 mg of Qingjin Huatantang water extract lyophilized powder could neutralize the activity of 1.8 U PDE at least. ConclusionThis study establishes a biological activity evaluation method of Qingjin Huatantang based on the inhibitory activity of PDE， and the anti-inflammatory activity of Qingjin Huatantang is characterized by international unit U of PDE activity， which can provide a new method for the determination of biological activity of traditional Chinese medicine compounds.

Mechanism of Yiyuan Qiwei Pills in Treatment of Diabetes Mellitus-induced Erectile Dysfunction / 中国实验方剂学杂志

ObjectiveTo observe the therapeutic effect of Yiyuan Qiwei pills （YYQW） on diabetes mellitus-induced induced erectile dysfunction （DMED） in rats and explore its regulation on the nitric oxide （NO）-cyclic guanosine monophosphate （cGMP） signaling pathway. MethodFifty-five healthy SD male rats of clean grade aged 2-3 months underwent intraperitoneal injection of streptozotocin （STZ） to induce the DMED model， and another 10 healthy SD male rats of clean grade aged 2-3 months were assigned to the control group. The model rats were randomly divided into a model group， a sildenafil group （5 mg·kg-1， ig）， and low-， medium-， and high-dose YYQW groups （1.5， 3.0， 6.0 g·kg-1， ig）. The rats in the model group and the control group were given normal saline by gavage at 10 mL·kg-1， once a day for two months. After intervention， the penile erectile function of rats in each group was measured by a pressure detection system. The pathological changes and ultrastructure of penile corpus cavernosum were observed by hematoxylin-eosin （HE） staining and transmission electron microscopy， respectively. The level of NO in the corpus cavernosum was detected by nitrate reductase. Enzyme-linked immunosorbent assay （ELISA） was used to detect the levels of cGMP and advanced glycation end products （AGEs）. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of endothelial nitric oxide synthase （eNOS）， neurogenic nitric oxide synthase （nNOS）， total nitric oxide synthase （NOS）， and phosphodiesterase type5 （PDE5） in rat penile tissues. The expression of above proteins was detected by Western blot. ResultCompared with the control group， the model group showed decreased intracavernous pressure （ICP）， NO， and cGMP levels， reduced mRNA and protein expression of nNOS and NOS， and increased PDE5 mRNA and protein expression （P<0.05）. Compared with the model group， the sildenafil group and the YYQW groups displayed increased ICP， NO， and cGMP levels， elevated mRNA and protein expression levels of nNOS and NOS， and reduced PDE5 mRNA and protein expression levels （P<0.05）. There were no pathological changes in the tissues and cell ultrastructure of the corpus cavernosum in the control group， while serious pathological changes were observed in the model group. Additionally， the sildenafil group and the YYQW groups were superior to the model group， the optimal effect was observed in the high-dose YYQW group. ConclusionYYQW can improve the penile erectile function of DMED rats and reduce the pathological damage of corpus cavernosum. The mechanism may be related to the promotion of nNOS and NOS expression， the inhibition of PDE5 expression， and the activation of the NO/cGMP signaling pathway.

Mechanism of Yiyuan Qiwei Pills in Treatment of Diabetes Mellitus-induced Erectile Dysfunction / 中国实验方剂学杂志

ObjectiveTo observe the therapeutic effect of Yiyuan Qiwei pills （YYQW） on diabetes mellitus-induced induced erectile dysfunction （DMED） in rats and explore its regulation on the nitric oxide （NO）-cyclic guanosine monophosphate （cGMP） signaling pathway. MethodFifty-five healthy SD male rats of clean grade aged 2-3 months underwent intraperitoneal injection of streptozotocin （STZ） to induce the DMED model， and another 10 healthy SD male rats of clean grade aged 2-3 months were assigned to the control group. The model rats were randomly divided into a model group， a sildenafil group （5 mg·kg-1， ig）， and low-， medium-， and high-dose YYQW groups （1.5， 3.0， 6.0 g·kg-1， ig）. The rats in the model group and the control group were given normal saline by gavage at 10 mL·kg-1， once a day for two months. After intervention， the penile erectile function of rats in each group was measured by a pressure detection system. The pathological changes and ultrastructure of penile corpus cavernosum were observed by hematoxylin-eosin （HE） staining and transmission electron microscopy， respectively. The level of NO in the corpus cavernosum was detected by nitrate reductase. Enzyme-linked immunosorbent assay （ELISA） was used to detect the levels of cGMP and advanced glycation end products （AGEs）. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of endothelial nitric oxide synthase （eNOS）， neurogenic nitric oxide synthase （nNOS）， total nitric oxide synthase （NOS）， and phosphodiesterase type5 （PDE5） in rat penile tissues. The expression of above proteins was detected by Western blot. ResultCompared with the control group， the model group showed decreased intracavernous pressure （ICP）， NO， and cGMP levels， reduced mRNA and protein expression of nNOS and NOS， and increased PDE5 mRNA and protein expression （P<0.05）. Compared with the model group， the sildenafil group and the YYQW groups displayed increased ICP， NO， and cGMP levels， elevated mRNA and protein expression levels of nNOS and NOS， and reduced PDE5 mRNA and protein expression levels （P<0.05）. There were no pathological changes in the tissues and cell ultrastructure of the corpus cavernosum in the control group， while serious pathological changes were observed in the model group. Additionally， the sildenafil group and the YYQW groups were superior to the model group， the optimal effect was observed in the high-dose YYQW group. ConclusionYYQW can improve the penile erectile function of DMED rats and reduce the pathological damage of corpus cavernosum. The mechanism may be related to the promotion of nNOS and NOS expression， the inhibition of PDE5 expression， and the activation of the NO/cGMP signaling pathway.

Structure-based discovery of orally efficient inhibitors via unique interactions with H-pocket of PDE8 for the treatment of vascular dementia

Our previous study demonstrated that phosphodiesterase 8 (PDE8) could work as a potential target for vascular dementia (VaD) using a chemical probe 3a. However, compound 3a is a chiral compound which was obtained by chiral resolution on HPLC, restricting its usage in clinic. Herein, a series of non-chiral 9-benzyl-2-chloro-adenine derivatives were discovered as novel PDE8 inhibitors. Lead 15 exhibited potent inhibitory activity against PDE8A (IC50 = 11 nmol/L), high selectivity over other PDEs, and remarkable drug-like properties (worthy to mention is that its bioavailability was up to 100%). Oral administration of 15 significantly improved the cAMP level of the right brain and exhibited dose-dependent effects on cognitive improvement in a VaD mouse model. Notably, the X-ray crystal structure of the PDE8A-15 complex showed that the potent affinity and high selectivity of 15 might come from the distinctive interactions with H-pocket including T-shaped π-π interactions with Phe785 as well as a unique H-bond network, which have never been observed in other PDE-inhibitor complex before, providing new strategies for the further rational design of novel selective inhibitors against PDE8.

Rectal roflumilast improves trinitrobenzenesulfonic acid-induced chronic colitis in rats

Roflumilast, a highly selective oral phosphodiesterase IV inhibitor, exerts anti-inflammatory and anti-fibrotic effects. Oral roflumilast causes gastrointestinal side effects, especially vomiting, which could be reduced by administering roflumilast via off-label routes. Inhaled roflumilast reportedly improved inflammatory and histopathological changes in asthmatic mice. The current study investigated the effects of oral and rectal roflumilast on trinitrobenzenesulfonic acid (TNBS)-induced chronic colitis in rats, an experimental model resembling human Crohn's disease. Five groups of rats (n=8) were used: normal control, TNBS-induced colitis, and three TNBS-treated colitic groups, which received oral sulfasalazine (500 mg·kg-1·day-1), oral roflumilast (5 mg·kg-1·day-1), or rectal roflumilast (5 mg·kg-1·day-1) for 15 days after colitis induction. Then, the following were assessed: the colitis activity score, tumor necrosis factor (TNF)-α, interleukin (IL)-2, and IL-6 serum levels, colonic length, and myeloperoxidase, malonaldehyde, and glutathione levels. Histological examinations employed H&E, Masson trichrome, and PAS stains in addition to immunostaining for KI-67 and TNF-α. The TNBS-induced colitis rats showed significant increases in disease activity scores, serum TNF-α, IL-2, and IL-6 levels, and colonic myeloperoxidase and malonaldehyde content. They also showed significant decreases in colonic length and glutathione levels in addition to histopathological and immunohistochemical changes. All the treatments significantly improved all these changes. Sulfasalazine provided the greatest improvement, followed by oral roflumilast, and then rectal roflumilast. In conclusion, both oral and rectal roflumilast partially improved TNBS-induced chronic colitis, suggesting the potential of roflumilast as an additional treatment for Crohn's disease.