Macrophage modulation with dipeptidyl peptidase-4 inhibitors:A new frontier for treating diabetic cardiomyopathy?

This editorial introduces the potential of targeting macrophage function for diabetic cardiomyopathy(DCM)treatment by dipeptidyl peptidase-4(DPP-4)inhibitors.Zhang et al studied teneligliptin,a DPP-4 inhibitor used for diabetes management,and its potential cardioprotective effects in a diabetic mouse model.They suggested teneligliptin administration may reverse established markers of DCM,including cardiac hypertrophy and compromised function.It also inhibited the NLRP3 inflammasome and reduced inflammatory cytokine production in diabetic mice.Macrophages play crucial roles in DCM pathogenesis.Chronic hyperglycemia disturbs the balance between pro-inflammatory(M1)and antiinflammatory(M2)macrophages,favoring a pro-inflammatory state contributing to heart damage.Here,we highlight the potential of DPP-4 inhibitors to modulate macrophage function and promote an anti-inflammatory environment.These compounds may achieve this by elevating glucagon-like peptide-1 levels and potentially inhibiting the NLRP3 inflammasome.Further studies on teneligliptin in combination with other therapies targeting different aspects of DCM could be suggested for developing more effective treatment strategies to improve cardiovascular health in diabetic patients.

Dipeptidyl peptidase-4 inhibitor for steroid-induced diabetes

The addition of the dipeptidyl peptidase-4 (DDP-4) inhibitor has been reported to achieve greater improvements in glucose metabolism with fewer adverse events compared to increasing the metformin dose in type 2 diabetic patients. We present a patient with steroid-induced diabetes whose blood glucose levels were ameliorated by the use of the DPP-4 inhibitor, showing that the DPP-4 inhibitors may be an effective and safe oral anti-diabetic drug for steroid-induced diabetes.

Cardiovascular efficacy and safety of dipeptidyl peptidase-4 inhibitors:A meta-analysis of cardiovascular outcome trials

BACKGROUND Dipeptidyl peptidase-4(DPP-4)inhibitors are a generally safe and well tolerated antidiabetic drug class with proven efficacy in type 2 diabetes mellitus(T2DM).Recently,a series of large,randomized controlled trials(RCTs)addressing cardiovascular outcomes with DPP-4 inhibitors have been published.AIM To pool data from the aforementioned trials concerning the impact of DPP-4 inhibitors on surrogate cardiovascular efficacy outcomes and on major cardiac arrhythmias.METHODS We searched PubMed and grey literature sources for all published RCTs assessing cardiovascular outcomes with DPP-4 inhibitors compared to placebo until October 2020.We extracted data concerning the following“hard”efficacy outcomes:fatal and non-fatal myocardial infarction,fatal and non-fatal stroke,hospitalization for heart failure,hospitalization for unstable angina,hospitalization for coronary revascularization and cardiovascular death.We also extracted data regarding the risk for major cardiac arrhythmias,such as atrial fibrillation,atrial flutter,ventricular fibrillation and ventricular tachycardia.RESULTS We pooled data from 6 trials in a total of 52520 patients with T2DM assigned either to DPP-4 inhibitor or placebo.DPP-4 inhibitors compared to placebo led to a non-significant increase in the risk for fatal and non-fatal myocardial infarction[risk ratio(RR)=1.02,95%CI:0.94-1.11,I2=0%],hospitalization for heart failure(RR=1.09,95%CI:0.92-1.29,I2=65%)and cardiovascular death(RR=1.02,95%CI:0.93-1.11,I2=0%).DPP-4 inhibitors resulted in a non-significant decrease in the risk for fatal and non-fatal stroke(RR=0.96,95%CI:0.85-1.08,I2=0%)and coronary revascularization(RR=0.99,95%CI:0.90-1.09,I2=0%),Finally,DPP-4 inhibitors demonstrated a neutral effect on the risk for hospitalization due to unstable angina(RR=1.00,95%CI:0.85-1.18,I2=0%).As far as cardiac arrhythmias are concerned,DPP-4 inhibitors did not significantly affect the risk for atrial fibrillation(RR=0.95,95%CI:0.78-1.17,I2=0%),while they were associated with a significant increase in the risk for atrial flutter,equal to 52%(RR=1.52,95%CI:1.03-2.24,I2=0%).DPP-4 inhibitors did not have a significant impact on the risk for any of the rest assessed cardiac arrhythmias.CONCLUSION DPP-4 inhibitors do not seem to confer any significant cardiovascular benefit for patients with T2DM,while they do not seem to be associated with a significant risk for any major cardiac arrhythmias,except for atrial flutter.Therefore,this drug class should not be the treatment of choice for patients with established cardiovascular disease or multiple risk factors,except for those cases when newer antidiabetics(glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors)are not tolerated,contraindicated or not affordable for the patient.

Dipeptidyl peptidase-4 inhibitor-induced autoimmune diseases:Current evidence

Dipeptidyl peptidase-4 inhibitors(DPP-4i)have an important place in the management of type 2 diabetes.The DPP-4 enzyme is ubiquitously distributed throughout the human body and has multiple substrates through which it regulates several important physiological functions.DPP-4 regulates several immune functions,including T-cell activation,macrophage function,and secretion of cytokines.Studies have reported an increase in autoimmune diseases like bullous pemphigoid,inflammatory bowel disease,and arthritis with DPP-4i use.The relationship of DPP-4i and autoimmune diseases is a complex one and warrants further research into the effect of DPP-4 inhibition on the immune system to understand the pathogenesis more clearly.Whether a particular cluster of autoimmune diseases is associated with DPP-4i use remains an important contentious issue.Nevertheless,a heightened awareness from the clinicians is required to identify and treat any such diseases.Through this review,we explore the clinical and pathophysiological characteristics of this association in light of recent evidence.

Review on the Effect of Glucagon-Like Peptide-1 Receptor Agonists and Dipeptidyl Peptidase-4 Inhibitors for the Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease（NAFLD） is a common liver disease and it represents the hepatic manifestation of metabolic syndrome, which includes type 2 diabetes mellitus（T2DM）, dyslipidemia, central obesity and hypertension. Glucagon-like peptide-1（GLP-1） analogues and dipeptidyl peptidase-4（DPP-4） inhibitors were widely used to treat T2 DM. These agents improve glycemic control, promote weight loss and improve lipid metabolism. Recent studies have demonstrated that the GLP-1 receptor（GLP-1R） is present and functional in human and rat hepatocytes. In this review, we present data from animal researches and human clinical studies that showed GLP-1 analogues and DPP-4 inhibitors can decrease hepatic triglyceride（TG） content and improve hepatic steatosis, although some effects could be a result of improvements in metabolic parameters. Multiple hepatocyte signal transduction pathways and m RNA from key enzymes in fatty acid metabolism appear to be activated by GLP-1 and its analogues. Thus, the data support the need for more rigorous prospective clinical trials to further investigate the potential of incretin therapies to treat patients with NAFLD.

Risk of pancreatic adverse events associated with the use of glucagon-like peptide-1 receptor agonist and dipeptidyl peptidase-4 inhibitor drugs: A systematic review and metaanalysis of randomized trials

AIM: To systematically assess risk of pancreatic adverse events with glucagon-like peptide-1(GLP-1) receptor agonist and dipeptidyl peptidase-4(DPP-4) inhibitor drugs.METHODS: We searched Pub Med, Embase, CINAHL, Cochrane review of clinical trials, pharmaceutical company clinical trials register, United States Food and Drug Administration website, European Medicines Agency website and Clinical Trials.gov for randomized controlled trials from inception to October 2013. Randomized control trial studies were selected for inclusion if they reported on pancreatic complication events and/or changes in pancreatic enzyme levels(serum amylase and serum lipase) as adverse events or as serious adverse events for patients who were on GLP-1 receptor agonist and DPP-4 inhibitor drugs. Two independent reviewers extracted data directly. We performed Peto odds ratio(OR) fixed effect meta-analysis of pancreatic adverse events a, and assessed heterogeneity with the I^2 statistic.RESULTS: Sixty-eight randomized controlled trials were eligible. A total of 60720 patients were included in our analysis of the association of risk of pancreatic complication events with GLP-1 agents. A total of 89 pancreatic related adverse events occurred among the GLP-1 agents compared to 74 events among the controls. There was a statistically significant increased risk of elevation of pancreatic enzymes associated with GLP-1 agents compared with control(Peto OR = 3.15, 95%CI: 1.56-6.39, P = 0.001, I2 = 0%). There was no statistically significant difference in the risk of pancreatic adverse event associated with GLP-1 agent compared with controls(Peto OR = 1.00, 95%CI: 0.73-1.37, P = 1.00, I2 = 0%). There were a total of 71 pancreatitis events in patients on GLP-1 agents and 56 pancreatitis events occurred in the control patients. There were 36 reports of pancreatic cancer in these studies. Of these cases, 2 used linagliptin, 2 used alogliptin, 1 used vildagliptin, 7 used saxagliptin while 6 used sitagliptin. The remaining 18 cases occurred among controls.CONCLUSION: Although GLP-1 based agents are associated with pancreatic enzyme elevation, we were unable to confirm a significant risk of pancreatitis or pancreatic cancer.

Neuroprotection by dipeptidyl-peptidase-4 inhibitors and glucagonlike peptide-1 analogs via the modulation of AKT-signaling pathway in Alzheimer’s disease

Alzheimer’s disease(AD)is the most common reason for progressive dementia in the elderly.It has been shown that disorders of the mammalian/mechanistic target of rapamycin(mTOR)signaling pathways are related to the AD.On the other hand,diabetes mellitus(DM)is a risk factor for the cognitive dysfunction.The pathogenesis of the neuronal impairment caused by diabetic hyperglycemia is intricate,which contains neuro-inflammation and/or neurodegeneration and dementia.Glucagon-like peptide-1(GLP1)is interesting as a possible link between metabolism and brain impairment.Modulation of GLP1 activity can influence amyloid-beta peptide aggregation via the phosphoinositide-3 kinase/AKT/mTOR signaling pathway in AD.The GLP1 receptor agonists have been shown to have favorable actions on the brain such as the improvement of neurological deficit.They might also exert a beneficial effect with refining learning and memory on the cognitive impairment induced by diabetes.Recent experimental and clinical evidence indicates that dipeptidyl-peptidase-4(DPP4)inhibitors,being currently used for DM therapy,may also be effective for AD treatment.The DPP-4 inhibitors have demonstrated neuroprotection and cognitive improvements in animal models.Although further studies for mTOR,GLP1,and DPP4 signaling pathways in humans would be intensively required,they seem to be a promising approach for innovative AD-treatments.We would like to review the characteristics of AD pathogenesis,the key roles of mTOR in AD and the preventive and/or therapeutic suggestions of directing the mTOR signaling pathway.

转染DPP-4 siRNA或(和)加入SP600125的小鼠肺泡巨噬细胞极化及JNK/AP-1信号通路激活情况观察

目的观察转染二肽基肽酶-4(DPP-4)siRNA或(和)加入c-Jun N-末端激酶(JNK)抑制剂(SP600125)的小鼠肺泡巨噬细胞极化情况、JNK/AP-1信号通路激活情况。方法体外培养小鼠肺泡巨噬细胞(MH-S),并随机分组:Control组转染空载siRNA、siDPP-4组转染DPP-4 siRNA、LPS组转染空载siRNA+LPS、siDPP-4+LPS组转染DPP-4 siRNA+LPS、LPS+SP600125组转染空载siRNA+LPS联合SP600125、siDPP-4+LPS+SP600125组转染DPP-4 siRNA+LPS联合SP600125。采用Western boltting法检测巨噬细胞中M1型和M2型极化标志物CD86、CD206蛋白及JNK、激活蛋白-1(AP-1)转录蛋白(c-Jun、c-Fos)磷酸化,RT-qPCR法检测巨噬细胞中M1型标志物(CD86、TNF-α、iNOS、IL-1β)和M2型标志物[CD206、精氨酸激酶-1(ARG-1)、IL-4、IL-10]mRNA,一氧化氮(NO)测定试剂盒、免疫荧光检测巨噬细胞上清液中M1型促炎因子NO和细胞内活性氧(ROS)生成情况。结果与Control组比较,LPS组M1型促炎型因子NO、ROS生成含量及M1型极化标志物(CD86蛋白及CD86、TNF-α、iNOS、IL-1βmRNA)表达升高,M2型极化标志物(CD206蛋白及CD206、ARG-1、IL-4、IL-10 mRNA)表达降低,P均<0.05。与LPS组比较,siDPP-4+LPS组M1型促炎型因子NO、ROS生成含量及M1型极化标志物(CD86蛋白及CD86、TNF-α、iNOS、IL-1βmRNA)表达升高,M2型极化标志物(CD206蛋白及CD206、ARG-1、IL-4、IL-10 mRNA)表达降低,P均<0.05。与LPS组比较,siDPP-4+LPS组p-JNK/JNK、p-c-Jun/c-Jun、p-c-Fos/c-Fos蛋白磷酸化相对表达量升高,P均<0.05。与siDPP-4+LPS组比较,siDPP-4+LPS+SP600125组p-JNK/JNK、p-c-Jun/c-Jun、p-c-Fos/c-Fos蛋白磷酸化相对表达量降低,P均<0.05。结论转染DPP-4 siRNA可促进LPS诱导的小鼠肺泡巨噬细胞M1型极化,抑制肺泡巨噬细胞M2型极化,并增加JNK、c-Jun、c-Fos蛋白磷酸化表达;加入JNK抑制剂后,可降低由转染DPP-4 siRNA引起的JNK、c-Jun、c-Fos蛋白磷酸化表达升高。转染DPP-4 siRNA促进LPS诱导的小鼠肺泡巨噬细胞M1型极化的作用机制可能与激活JNK/AP-1信号通路有关。

Efficacy of omarigliptin,once-weekly dipeptidyl peptidase-4 inhibitor,in patients with type 2 diabetes

BACKGROUND Omarigliptin is one of several once-weekly dipeptidyl peptidase-4 inhibitors(DPP-4is).Despite the high frequency of switching from various daily DPP-4is to omarigliptin in actual clinical practice,data regarding its efficacy in patients with type 2 diabetes(T2D)after switching are limited.AIM To analyze the efficacy of omarigliptin in Japanese patients with T2D who had previously received treatment with other glucose-lowering agents.METHODS Forty-nine T2D patients treated for the first time with omarigliptin were recruited retrospectively and divided into four groups defined as either add-on or switched from daily DPP-4is:switched from linagliptin,switched from sitagliptin,and switched from vildagliptin.During a 3-mo follow-up,the clinical parameters among these groups were assessed and compared,with the impact of the switch on glycemic variability as measured by continuous glucose monitoring also being evaluated in the switched groups.RESULTS Hemoglobin A1c levels saw a significant decrease of-0.32%±0.41%in the add-on group(P=0.002).However,the other groups’variables depended on the preswitch daily DPP-4i:switched from linagliptin,-0.05%±0.22%;switched from sitagliptin,-0.17%±0.33%;and switched from vildagliptin,0.45%±0.42%,which saw significant worsening(P=0.0007).Multivariate logistic regression analysis revealed that switching from vildagliptin to omarigliptin was independently associated with worsening glycemic control(P=0.0013).The mean and standard deviation of sensor glucose value,the mean amplitude of glycemic excursions,and the mean of daily difference significantly improved when switching the patient from either linagliptin or sitagliptin to omarigliptin.However,in patients switched from vildagliptin,not only did the glucose variability indices see no improvements,the mean of daily difference even underwent significant worsening.CONCLUSION Administering omarigliptin as add-on therapy or switching to it from sitagliptin and linagliptin,but not vildagliptin,improves glycemic control and thus should help in decision making when selecting DPP-4is for T2D patients.

Association between plasma dipeptidyl peptidase-4 levels and cognitive function in perinatal pregnant women with gestational diabetes mellitus

BACKGROUND Dipeptidyl peptidase-4(DPP4)is associated with cognitive dysfunction in patients with type 2 diabetes.AIM To assess a possible relationship between serum DPP4 and cognitive function in perinatal pregnant women with gestational diabetes mellitus(GDM).METHODS The study subjects were divided into three groups:GDM group(n=81),healthy pregnant(HP)group(n=85),and control group(n=51).The Montreal Cognitive Assessment(MoCA)was used to assess the cognitive status of each group.Venous blood samples were collected to measure blood lipids,glycated hemoglobin,and glucose levels.For each participant,a 3-mL blood sample was collected and centrifuged,and the serum was collected.Blood samples were stored at-80℃,and DPP4,interleukin-6(IL-6),and 8-iso-prostaglandin F2α(8-iso-PGF2α),and brain-derived neurotrophic factor(BDNF)were detected using ELISA.RESULTS The MoCA scores in the GDM and HP groups were significantly different from those in the control group in terms of visuospatial/executive function and attention(P<0.05);however,the scores were not significantly different between the GDM and HP groups(P>0.05).In terms of language,the GDM group had significantly different scores from those in the other two groups(P<0.05).In terms of memory,a significant difference was found between the HP and control groups(P<0.05),as well as between the GDM and HP groups.The levels of DPP4,IL-6,and 8-iso-PGF2αin the GDM group were significantly higher than those in the HP and control groups(P<0.05);however,the differences between these levels in the HP and control groups were not significant(P>0.05).The level of BDNF in the GDM group was significantly lower than that in the HP and control groups(P<0.05),although the difference in this level between the HP and control groups was not significant(P>0.05).CONCLUSION Cognitive dysfunction in perinatal pregnant women with GDM mainly manifested as memory loss,which might be associated with elevated DPP4 levels.

DPP-4 inhibitors and GLP-1RAs:cardiovascular safety and benefits

Glucagon-like peptide-1 receptor agonists(GLP-1RAs)and dipeptidyl peptidase-4 inhibitors are commonly used treatments for patients with type 2 diabetes mellitus(T2DM).Both anti-diabetic treatments function by playing key modulatory roles in the incretin system.Though these drugs have been deemed effective in treating T2DM,the Food and Drug Administration(FDA)and some members of the scientific community have questioned the safety of these therapeutics relative to important cardiovascular endpoints.As a result,since 2008,the FDA has required all new drugs for glycemic control in T2DM patients to demonstrate cardiovascular safety.The present review article strives to assess the safety and benefits of incretin-based therapy,a new class of antidiabetic drug,on the health of patient cardiovascular systems.In the process,this review will also provide a physiological overview of the incretin system and how key components function in T2DM.

Sodium-dependent glucose transporter 2 inhibitors effects on myocardial function in patients with type 2 diabetes and asymptomatic heart failure

BACKGROUND Sodium-dependent glucose transporter 2 inhibitors(SGLT2i)have shown efficacy in reducing heart failure(HF)burden in a very heterogeneous groups of patients,raising doubts about some contemporary assumptions of their mechanism of action.We previously published a prospective observational study that evaluated mechanisms of action of SGLT2i in patients with type 2 diabetes who were in HF stages A and B on dual hypoglycemic therapy.Two groups of patients were included in the study:the ones receiving SGLT2i as an add-on agent to metformin and the others on dipeptidyl peptidase-4 inhibitors as an add-on to metformin due to suboptimal glycemic control.AIM To evaluate the outcomes regarding natriuretic peptide,oxidative stress,inflammation,blood pressure,heart rate,cardiac function,and body weight.METHODS The study outcomes were examined by dividing each treatment arm into two subgroups according to baseline parameters of global longitudinal strain(GLS),N-terminal pro-brain natriuretic peptide,myeloperoxidase(MPO),high-sensitivity C-reactive protein(hsCRP),and systolic and diastolic blood pressure.To evaluate the possible predictors of observed changes in the SGLT2i arm during follow-up,a rise in stroke volume index,body mass index(BMI)decrease,and lack of heart rate increase,linear regression analysis was performed.RESULTS There was a greater reduction of MPO,hsCRP,GLS,and blood pressure in the groups with higher baseline values of mentioned parameters irrespective of the therapeutic arm after 6 months of follow-up.Significant independent predictors of heart rate decrease were a reduction in early mitral inflow velocity to early diastolic mitral annular velocity at the interventricular septal annulus ratio and BMI,while the predictor of stroke volume index increase was SGLT2i therapy itself.CONCLUSION SGLT2i affect body composition,reduce cardiac load,improve diastolic/systolic function,and attenuate the sympathetic response.Glycemic control contributes to the improvement of heart function,blood pressure control,oxidative stress,and reduction in inflammation.

二肽基肽酶-4抑制剂联合二甲双胍对2型糖尿病的疗效及安全性

目的探讨二肽基肽酶-4（dipeptide base peptidase 4,DPP-4）抑制剂和二甲双胍在单独或联合用药对2型糖尿病的疗效及安全性。方法选取2012年12月~2015年6月间于唐山市丰润区人民医院和唐山车城医院收诊的90例确诊为2型糖尿病的患者,随机分为治疗组（DPP-4抑制剂组）、对照组（二甲双胍组）和联合用药组,每组各30例。经3个月治疗,对比治疗前后患者空腹血糖（free blood glucose,FBG）、餐后2小时血糖（2h PG）、糖化血红蛋白（Hb A1c）等指标水平,并对治疗期间的低血糖率及不良反应进行监测及统计。结果经治疗3个月后,FBG、2h PG、Hb A1c及低密度脂蛋白胆固醇（LDL-C）均显著下降,差异有统计学意义（P〈0.05）,而联合用药组较治疗组和对照组具有更好的疗效（P〈0.05）。联合用药组与治疗组和对照组相比不良反应发生率显著降低,差异有统计学意义（P〈0.05）,未发生低血糖病例,对体重指数（body mass index,BMI）影响较小。结论 DPP-4抑制剂联合二甲双胍对2型糖尿病患者的治疗效果更佳,具有更好的安全性。

DPP-4抑制剂与二甲双胍固定剂量复合剂的疗效综合评价

经典降糖药二甲双胍为2型糖尿病治疗的首选用药,二肽基肽酶-4(dipeptide base peptidase 4,DPP-4)抑制剂作为一种新型的降糖药,可增加体内肠促胰素水平,促进胰岛素分泌,保护β细胞功能。二甲双胍与DPP-4抑制剂互补的降糖机制标志着两者固定剂量复合(fixed dose combinations,FDC)制剂有较好的临床应用前景。多项研究表明,DPP-4抑制剂/二甲双胍FDC制剂可有效降低Hb A1c、空腹血糖及餐后血糖,低血糖发生率低,不增加体重,而且可提高患者的依从性。

DPP-4抑制剂的心血管安全性:现状与未来

心脑血管疾病是糖尿病严重并发症之一,是2型糖尿病患者死亡的首要原因。在糖尿病治疗中,不仅要关注患者的血糖控制水平,还要了解所使用降糖药物对心血管系统的影响,争取为患者带来更大的获益。目前在临床中使用的降糖药物,是否能够在良好控制血糖的同时兼具心血管效应是我们应该关注的问题,特别是新近进入临床使用的肠促胰素类药物的心血管安全性更是值得关注。关于DPP-4抑制剂的心血管安全性的大型前瞻性研究将为DPP-4抑制剂的心血管安全性提供更加充分的循证医学证据。

MK-0626,a selective DPP-4 inhibitor,attenuates hepatic steatosis in ob/ob mice

AIM: To investigate the mechanism and in vivo effects of MK-0626, a dipeptidyl peptidase-4 inhibitor, on hepatic steatosis using ob/ob mice.

二肽基肽酶-4通过CXCR4/mTOR信号通路介导小鼠肺泡巨噬细胞MH-S自噬的机制研究

目的探究二肽基肽酶-4(DPP-4)通过趋化因子受体4(CXCR4)/哺乳动物雷帕霉素靶蛋白(mTOR)信号通路介导小鼠肺泡巨噬细胞MH-S自噬的机制。方法体外培养小鼠肺泡巨噬细胞MH-S并分组转染。分别设置PBS组(PBS培养MH-S细胞)、LPS组(100 ng/mL LPS诱导24 h)、DPP-4组(DPP-4表达病毒转染)、si-DPP-4组(si-DPP-4病毒载体转染)、DPP-4+BafA1组(DPP-4表达病毒转染+自噬抑制剂BafA1干预)及si-DPP-4+BafA1组(si-DPP-4病毒载体转染+自噬抑制剂BafA1干预)。绿色荧光蛋白(GFP)检测转染效率,稳定转染后,酶联免疫吸附试验检测MH-S细胞上清液炎症因子水平,腺病毒检测MH-S细胞自噬流变化,实时荧光定量聚合酶链反应检测细胞DPP-4、CXCR4、mTOR mRNA的表达,Western blottig检测CXCR4/mTOR通路蛋白的表达。结果LPS组IL-1β、IL-6、TNF-α、GFP、RPF、Merge数量,CXCR4mRNA、mTOR mRNA和CXCR4蛋白、p-mTOR/mTOR蛋白相对表达量高于PBS组(P<0.05);DPP-4组与LPS组IL-1β、IL-6及TNF-α水平比较,差异无统计学意义(P>0.05);DPP-4组GFP、RPF、Merge数量,DPP-4 mRNA相对表达量高于LPS组(P<0.05),CXCR4 mRNA、mTOR mRNA、CXCR4蛋白、pmTOR/mTOR蛋白相对表达量低于LPS组(P<0.05);si-DPP-4组IL-1β、IL-6、TNF-α水平高于LPS组(P<0.05),GFP、RPF及MergeMerge数量低于LPS组(P<0.05);si-DPP-4组和DPP-4+BafA1组IL-1β、IL-6、TNF-α水平、CXCR4蛋白、p-mTOR/mTOR蛋白相对表达量高于DPP-4组(P<0.05),GFP、RPF及Merge数量低于DPP-4组(P<0.05);si-DPP-4组DPP-4 mRNA相对表达量低于DPP-4组(P<0.05),CXCR4 mRNA、mTOR mRNA相对表达量高于DPP-4组(P<0.05);si-DPP-4+BafA1组IL-1β、IL-6水平、CXCR4 mRNA、mTOR m RNA、CXCR4蛋白、p-mTOR/mTOR蛋白相对表达量高于si-DPP-4组(P<0.05),GFP、RPF、Merge数量低于si-DPP-4组(P<0.05)。结论DPP-4能够调节小鼠肺巨噬细胞自噬作用,调控炎症反应,其作用机制可能与CXCR4/mTOR通路有关。

计算机模拟纳豆源多肽与DPP-IV和SARS-CoV-2Mpro的相互作用

兼具糖尿病的新型冠状病毒肺炎(Corona Virus Disease2019,COVID-19)患者病死率明显偏高,抑制Ⅱ型糖尿病关键酶二肽基肽酶4(DPP-IV)和新冠肺炎病毒主蛋白酶(SARS-CoV-2 Mpro)的活性能缓解相应的病症。该研究采用UniProt、NCBI和PDB数据库检索纳豆蛋白,基于BIOPBP-UWM数据库开展计算机模拟胃肠道蛋白酶(胃蛋白酶、胰蛋白酶和胰凝乳蛋白酶)水解纳豆蛋白的研究,最后利用分子对接技术分别研究纳豆蛋白源多肽与DPP-IV和SARS-CoV-2 Mpro的结合能力,分析参与相互作用的氨基酸残基与分子作用力类型。结果发现,糖转运蛋白与两种酶具有良好的结合效果。特别地,序列为ISQPR、TIPVR和STVTR的多肽对两种酶都具有较高的结合分数(≤-130),被鉴定为DPP-IV和SARS-CoV-2Mpro的双重抑制肽。因此,纳豆蛋白具有缓解Ⅱ型糖尿病病症和作为新型冠状病毒感染病人营养补充剂的潜力。

Renoprotection Provided by Dipeptidyl Peptidase-4 Inhibitors in Combination with Angiotensin Receptor Blockers in Patients with Type 2 Diabetic Nephropathy

Background: Treatment with the dipeptidyl peptidase-4 inhibitors (DPP4i) and angiotensin receptor blockers (ARBs) in patients with type 2 diabetic nephropathy (DN) has not been well characterized. This study aimed to assess the renoprotection of this combined treatment in DN patients.Methods: A total of 159 type 2 DN patients from 2013 to 2015 were enrolled retrospectively from a prospective DN cohort at the National Clinical Research Center of Kidney Diseases, Jinling Hospital (China). Fifty-seven patients received DPP4i and ARB treatment, and 102 patients were treated with ARBs alone. All patients were followed up for at least 12 months. Statistical analyses were performed using Stata version 12.0.Results: There were no significant differences at baseline for age, sex, body mass index, duration of diabetes, fasting blood glucose (FBG), hemoglobin A1c (HbA1c), and estimated glomerular filtration rate (eGFR) between the two groups. Antihypertensive and antidiabetic medication use was similar in each group except calcium channel antagonists (P = 0.032). No significant changes in FBG and HbA1c were observed in the two groups after treatment. The eGFR decreased slower in the DPP4i + ARB group than in the ARB group at 12 months (?12 months: -2.48 ± 13.86 vs. -6.81 ± 12.52 ml·min–1·1.73m–2,P = 0.044). In addition, proteinuria was decreased further in the DPP4i + ARB group than in the ARB group after 24 months of treatment (?24 months: -0.18 [-1.00, 0.17] vs. 0.32 [-0.35, 0.88],P = 0.031). There were 36 patients with an eGFR decrease of more than 30% over 24 months. After adjusting for FBG, HbA1c, and other risk factors, DPP4i + ARB treatment was still associated with a reduced incidence of an eGFR decrease of 20% or 30%.Conclusions: The combined treatment of DPP4i and ARBs is superior to ARBs alone, as evidenced by the greater proteinuria reduction and lower eGFR decline. In addition, the renoprotection of DPP4i combined with ARBs was independent of glycemic control.

二肽基肽酶抑制剂类似物对LPS诱导的小胶质细胞炎症反应的抑制作用

目的探讨二肽基肽酶抑制剂类似物对脂多糖(LPS)诱导的小胶质细胞炎症反应的抑制作用及机制。方法取新生SD大鼠进行小胶质细胞的原代培养并分离纯化。本研究分为空白组、阴性对照组、LPS组、药物组(每组平行测定3次),药物提前48 h预处理。使用MTT法筛选LPS诱导小胶质细胞增殖的最佳浓度,观察不同浓度下二肽基肽酶抑制剂类似物对LPS刺激小胶质细胞的作用。使用ELISA检测细胞上清液中白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)的含量,Western blotting法检测Toll样受体4(TLR-4)蛋白的表达,RT-PCR法检测NF-κB mRNA的表达。结果经LPS刺激后,SD大鼠小胶质细胞生长迅速,并可检测到大量炎性因子释放。与空白组相比,加入二肽基肽酶抑制剂类似物后,LPS诱导的小胶质细胞增殖被明显抑制,处理48 h后对小胶质细胞的IC50为1.014×10-2μmol/L。二肽基肽酶抑制剂类似物能明显抑制小胶质细胞TNF-α和IL-1β的释放(P<0.01),并降低小胶质细胞TLR-4和NF-κB的表达。结论二肽基肽酶抑制剂类似物对LPS刺激的小胶质细胞增殖及炎症反应具有抑制作用,可能与抑制小胶质细胞TLR-4、NF-κB表达有关。