Increased endothelin receptor B and G protein coupled kinase-2 in the mesentery of portal hypertensive rats

AIM: To elucidate the mechanisms of mesenteric vasodilation in portal hypertension (PHT), with a focus on endothelin signaling. METHODS: PHT was induced in rats by common bile duct ligation (CBDL). Portal pressure (PP) was measured directly via catheters placed in the portal vein tract. The level of endothelin-1 (ET-1) in the mesenteric circulation was determined by radioimmunoassay, and the expression of the endothelin A receptor (ETAR) and endothelin B receptor (ETBR) was assessed by immunofluorescence and Western blot. Additionally, expression of G protein coupled kinase-2 (GRK2) and β-arrestin 2, which influence endothelin receptor sensitivity, were also studied by Western blot. RESULTS: PP of CBDL rats increased significantly (11.89 ± 1.38 mmHg vs 16.34 ± 1.63 mmHg). ET-1 expression decreased in the mesenteric circulation 2 and 4 wk after CBDL. ET-1 levels in the systemic circulation of CBDL rats were increased at 2 wk and decreased at 4 wk. There was no change in ETAR expression in response to CBDL; however, increased expression of ETBR in the endothelial cells of mesenteric arterioles and capillaries was observed. In sham-operated rats, ETBR was mainly expressed in the CD31+ endothelial cells of the arterioles. With development of PHT, in addition to the endothelial cells, ETBR expression was noticeably detectable in the SMA+ smooth muscle cells of arterioles and in the CD31+ capillaries. Following CBDL, increased expression of GRK2 was also found in mesenteric tissue, though there was no change in the level of β-arrestin 2. CONCLUSION: Decreased levels of ET-1 and increased ETBR expression in the mesenteric circulation following CBDL in rats may underlie mesenteric vasodilation in individuals with PHT. Mechanistically, increased GRK2 expression may lead to desensitization of ETAR, as well as other vasoconstrictors, promoting this vasodilatory effect.

Adrenal G protein-coupled receptor kinase-2 in regulation of sympathetic nervous system activity in heart failure

Heart failure(HF), the number one cause of death in the western world, is caused by the insufficient performance of the heart leading to tissue underperfusion in response to an injury or insult. It comprises complex interactions between important neurohormonal mechanisms that try but ultimately fail to sustain cardiac output. The most prominent such mechanism is the sympathetic(adrenergic) nervous system(SNS), whose activity and outflow are greatly elevated in HF. SNS hyperactivity confers significant toxicity to the failing heart and markedly increases HF morbidity and mortality via excessive activation of adrenergic receptors, which are G protein-coupled receptors. Thus, ligand binding induces their coupling to heterotrimeric G proteins that transduce intracellular signals. G protein signaling is turned-off by the agonist-bound receptor phosphorylation courtesy of G protein-coupled receptor kinases(GRKs), followed by βarrestin binding, which prevents the GRK-phosphorylated receptor from further interaction with the G proteins and simultaneously leads it inside the cell(receptor sequestration). Recent evidence indicates that adrenal GRK2 and βarrestins can regulate adrenal catecholamine secretion, thereby modulating SNS activity in HF. The present review gives an account of all these studies on adrenal GRKs and βarrestins in HF and discusses the exciting new therapeutic possibilities for chronic HF offered by targeting these proteins pharmacologically.

Roles of G protein-coupled receptors in inflammatory bowel disease

Inflammatory bowel disease(IBD)is a complex disease with multiple pathogenic factors.Although the pathogenesis of IBD is still unclear,a current hypothesis suggests that genetic susceptibility,environmental factors,a dysfunctional immune system,the microbiome,and the interactions of these factors substantially contribute to the occurrence and development of IBD.Although existing and emerging drugs have been proven to be effective in treating IBD,none can cure IBD permanently.G protein-coupled receptors(GPCRs)are critical signaling molecules implicated in the immune response,cell proliferation,inflammation regulation and intestinal barrier maintenance.Breakthroughs in the understanding of the structures and functions of GPCRs have provided a driving force for exploring the roles of GPCRs in the pathogenesis of diseases,thereby leading to the development of GPCR-targeted medication.To date,a number of GPCRs have been shown to be associated with IBD,significantly advancing the drug discovery process for IBD.The associations between GPCRs and disease activity,disease severity,and disease phenotypes have also paved new avenues for the precise management of patients with IBD.In this review,we mainly focus on the roles of the most studied proton-sensing GPCRs,cannabinoid receptors,and estrogen-related GPCRs in the pathogenesis of IBD and their potential clinical values in IBD and some other diseases.

MicroRNA-760 acts as a tumor suppressor in gastric cancer development via inhibiting G-protein-coupled receptor kinase interacting protein-1 transcription

BACKGROUND Gastric cancer(GC)has become a serious threat to people's health.Accumulative evidence reveals that dysregulation of numerous microRNAs(miRNAs)has been found during malignant formation.So far,the role of microRNA-760(miR-760)in the development of GC is largely unknown.AIM To measure the expression level of miR-760 in GC and investigate its role in gastric tumorigenesis.METHODS Real-time quantitative polymerase chain reaction and Western blot analysis were used to measure the expression of miR-760 and G-protein-coupled receptor kinase interacting protein-1(GIT1).Cell growth was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide(MTT)and cell colony formation assays.Apoptosis was assessed by flow cytometric analysis.The relationship between miR-760 and GIT1 was verified by luciferase reporter assay.RESULTS The results showed that the expression of miR-760 was decreased in GC and associated with poor clinical outcomes in GC patients.Furthermore,miR-760 restrained cell proliferation and cell colony formation and induced apoptosis in GC cells.In addition,miR-760 directly targeted GIT1 and negatively regulated its expression in GC.GIT1 was upregulated in GC and predicted a worse prognosis in GC patients.We also found that upregulation of GIT1 weakened the inhibitory CONCLUSION In conclusion,miR-760 targets GIT1 to inhibit cell growth and promote apoptosis in GC cells.Our data demonstrate that miR-760 may be a potential target for the treatment of GC.

G protein-coupled estrogen receptor in colon function, immune regulation and carcinogenesis

Estrogens play important roles in the development and progression of multiple tumor types.Accumulating evidence points to the significance of estrogen action not only in tumors of hormonally regulated tissues such as the breast,endometrium and ovary,but also in the development of colorectal cancer(CRC).The effects of estrogens in physiological and pathophysiological conditions are mediated by the nuclear estrogen receptorsαandβ,as well as the membranebound G protein-coupled estrogen receptor(GPER).The roles of GPER in CRC development and progression,however,remain poorly understood.Studies on the functions of GPER in the colon have shown that this estrogen receptor regulates colonic motility as well as immune responses in CRC-associated diseases,such as Crohn’s disease and ulcerative colitis.GPER is also involved in cell cycle regulation,endoplasmic reticulum stress,proliferation,apoptosis,vascularization,cell migration,and the regulation of fatty acid and estrogen metabolism in CRC cells.Thus,multiple lines of evidence suggest that GPER may play an important role in colorectal carcinogenesis.In this review,we present the current state of knowledge regarding the contribution of GPER to colon function and CRC.

New insights into sodium transport regulation in the distal nephron:Role of G-protein coupled receptors

The renal handling of Na^+ balance is a major determinant of the blood pressure(BP) level. The inability of the kidney to excrete the daily load of Na+ represents the primary cause of chronic hypertension. Among the different segments that constitute the nephron, those present in the distal part(i.e., the cortical thick ascending limb, the distal convoluted tubule, the connecting and collecting tubules) play a central role in the fine-tuning of renal Na^+ excretion and are the target of many different regulatory processes that modulate Na^+ retention more or less efficiently. G-protein coupled receptors(GPCRs) are crucially involved in this regulation and could represent efficient pharmacological targets to control BP levels. In this review, we describe both classical and novel GPCR-dependent regulatory systems that have been shown to modulate renal Na^+ absorption in the distal nephron. In addition to the multiplicity of the GPCR that regulate Na^+ excretion, this review also highlights the complexity of these different pathways, and the connections between them.

Isoleucine, an Essential Amino Acid, Induces the Expression of Human <i>β</i>Defensin 2 through the Activation of the G-Protein Coupled Receptor-ERK Pathway in the Intestinal Epithelia

Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides that are expressed in the colonic epithelia. This study investigated the effect and the signaling mechanism of inducible β-defensin HBD2 by an essential amino acid, isoleucine (Ile) in colonic epithelial cells. Here we examined the expression level of HBD2 on induction of Ile in epithelial cells, and checked this pathway. HBD2 mRNA was induced by co-incubation with IL-1α and Ile in Caco2 cells, but not by Ile alone. An inhibitor of either ERK or Gi, a subunit of G-proteins, reduced the induction of HBD2 mRNA by Ile. The treatment with Ile also increased the intracellular calcium ion concentration, thus suggesting that the GPCR and ERK signaling pathway mediate the effects of Ile. These results indicate that an essential amino acid, Ile, enhances the expression of an inducible β-defensin, namely HBD2, by IL-1α through the activation of GPCRs and ERK signaling pathway. The administration of Ile may therefore represent a possible option to safely treat intestinal inflammation.

Desensitization of G-protein-coupled receptors induces vascular hypocontractility in response to norepinephrine in the mesenteric arteries of cirrhotic patients and rats

BACKGROUND: The increased β-arrestin-2 and its combination with G-protein-coupled receptors (GPCRs) lead to GPCRs desensitization. The latter may be responsible for decreased contractile reactivity in the mesenteric arteries of cirrhotic patients and rats. The present study is to investigate the machinery changes of α-adrenergic receptors and G proteins and their roles in the contractility of mesenteric arteries of cirrhotic patients and animal models. METHODS: Patients with cirrhosis due to hepatitis B and cirrhotic rats induced by CCl 4 were studied. Mesenteric artery contractility in response to norepinephrine was determined by a vessel perfusion system. The contractile effect of G protein-coupled receptor kinase-2 (GRK-2) inhibitor on the mesenteric artery was evaluated. The protein expression of the α 1 adrenergic receptor, G proteins, β-arrestin-2, GRK-2 as well as the activity of Rho associated coiled-coil forming protein kinase-1 (ROCK-1) were measured by Western blot. In addition, the interaction of α 1 adrenergic receptor with β-arrestin-2 was assessed by co-immunoprecipitation. RESULTS: The portal vein pressure of cirrhotic patients and rats was significantly higher than that of controls. The doseresponse curve to norepinephrine in mesenteric arteriole was shifted to the right, and EC 50 was significantly increased in cirrhotic patients and rats. There were no significant differences in the expressions of the α 1 adrenergic receptor and G proteins in the cirrhotic group compared with the controls. However, the protein expressions of GRK-2 and β-arrestin-2 were significantly elevated in cirrhotic patients and rats compared with those of the controls. The interaction of the α 1 adrenergic receptor and β-arrestin-2 was significantly aggravated. This interaction was significantly reversed by GRK-2 inhibitor. Both the protein expression and activity of ROCK-1 were significantly decreased in the mesenteric artery in patients with cirrhosis compared with those of the controls, and this phenomenon was not shown in the cirrhotic rats. Norepinephrine significantly increased the activity of ROCK-1 in normal rats but not in cirrhotic ones. Norepinephrine significantly increased ROCK-1 activity in cirrhotic rats when GRK-2 inhibitor was used. CONCLUSIONS: β-arrestin-2 expression and its interaction with GPCRs are significantly upregulated in the mesenteric arteries in patients and rats with cirrhosis. These upregulations result in GPCR desensitization, G-protein dysfunction and ROCK inhibition. These may explain the decreased contractility of the mesenteric artery in response to vasoconstrictors.

Overexpression of G protein-coupled receptor 31 as a poor prognosticator in human colorectal cancer

AIM To investigate the expression of G protein-coupled receptor 31 (GPR31) and its clinical significance in human colorectal cancer (CRC).METHODS To determine the association between the GPR31 expression and the prognosis of patients, we obtained paraffin-embedded pathological specimens from 466 CRC patients who underwent initial resection. A total of 321 patients from the First Affiliated Hospital of Sun Yat-sen University from January 1996 to December 2008 were included as a training cohort, whereas 145 patients from the Sixth Affiliated Hospital of Sun Yat-sen University from January 2007 to November 2008 were included as a validation cohort. We examined GPR31 expression levels in CRC tissues from two independent cohorts via immunohistochemical staining. All patients were categorized into either a GPR31 low expression group or a GPR31 high expression group. The clinicopathological factors and the prognosis of patients in the GPR31 low expression group and GPR31 high expression group were compared.RESULTS We compared the clinicopathological factors and the prognosis of patients in the GPR31 low expression group and GPR31 high expression group. Significant differences were observed in the number of patients in pM classification between patients in the GPR31 low expression group and GPR31 high expression group (P = 0.007). The five-year survival and tumor-free survival rates of patients were 84.3% and 82.2% in the GPR31 low expression group, respectively, and both rates were 59.7% in the GPR31 high expression group (P < 0.05). Results of the Cox proportional hazard regression model revealed that GPR31 upregulation was associated with shorter overall survival and tumor-free survival of patients with CRC (P < 0.05). Multivariate analysis identified GPR31 expression in colorectal cancer as an independent predictive factor of CRC patient survival (P < 0.05).CONCLUSION High GPR31 expression levels were found to be correlated with pM classification of CRC and to serve as an independent predictive factor of poor survival of CRC patients.

Insights into the structural biology of G-protein coupled receptors impacts drug design for central nervous system neurodegenerative processes

In the last few years, there have been important new insights into the structural biology of G-protein coupled receptors. It is now known that allosteric binding sites are involved in the affinity and selec- tivity of ligands for G-protein coupled receptors, and that signaling by these receptors involves both G-protein dependent and independent pathways. The present review outlines the physiological and pharmacological implications of this perspective for the design of new drugs to treat disorders of the central nervous system. Specifically, new possibilities are explored in relation to allosteric and or- thosteric binding sites on dopamine receptors for the treatment of Parkinson＇s disease, and on muscarinic receptors for Alzheimer＇s disease. Future research can seek to identify ligands that can bind to more than one site on the same receptor, or simultaneously bind to two receptors and form a dimer. For example, the design of bivalent drugs that can reach homo/hetero-dimers of D2 dopa- mine receptor holds promise as a relevant therapeutic strategy for Parkinson＇s disease. Regarding the treatment of Alzheimer＇s disease, the design of dualsteric ligands for mono-oligomeric mus- carinic receptors could increase therapeutic effectiveness by generating potent compounds that could activate more than one signaling pathway.

Functionally diverse ligands modulate different activation states of the formyl peptide receptor 2,a G protein-coupled receptor

OBJECTIVE To identify the mechanisms by which the formyl peptide receptor 2(FPR2)mediates both inflammatory and anti-inflammatory signaling in an agonist-dependent manner.METHODS Cells expressing FPR2 were incubated with weak agonists,Aβ42 and Ac2-26,before stimulation with a strong agonist,WKYMVm.Calcium mobilization,c AMP inhibition and MAP kinase activation were measured.Intramolecular FRET were determined using FPR2 constructs with an ECFP attached to the C-terminus and a Fl As H binding motif embedded in the first or third intracellular loop(IL1 or IL3,respectively).RESULTS Aβ42 did not induce significant Ca^(2+) mobilization,but positively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction in a dose-variable manner within a narrow range of ligand concentrations.Treating FPR2-expressing cells with Ac2-26,a peptide with anti-inflammatory activity,negatively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction.Intramolecular FRET assay showed that stimulation of the receptor constructs with Aβ42 brought the C-terminal domain closer to IL1 but away from IL3.An opposite conformational change was induced by Ac2-26.The FPR2 conformation induced by Aβ42 corresponded to enhanced ERK phosphorylation and attenuated p38 MAPK phosphorylation,whereas Ac2-26 induced FPR2 conformational change corresponding to elevated p38 MAPK phosphorylation and reduced ERK phosphorylation.CONCLUSION Aβ42 and Ac2-26 induce different conformational changes in FPR2.These findings provide a structural basis for FPR2 mediation of inflammatory vs anti-inflammatory functions and identify a type of receptor modulation that differs from the classic positive and negative allosteric modulation.

Kiss-1/GPR54系统在PCOS模型大鼠卵巢颗粒细胞中的表达及对卵泡发育障碍的作用机制

目的初步探讨Kiss-1/GPR54系统在多囊卵巢综合征(PCOS)模型大鼠卵巢颗粒细胞中的表达,并分析其与PCOS之间的关联。方法筛选出14只动情规律的雌性SD大鼠,按照随机数字表法分为正常对照组和模型组,每组7只。其中模型组大鼠予来曲唑-羧甲基纤维素混悬液0.1mg/(kg·d)连续灌胃21 d以构建PCOS大鼠模型。收集大鼠血清、卵巢组织、卵巢颗粒细胞。然后计算大鼠卵巢指数,对卵巢组织进行苏木精-伊红染色法,采用酶联免疫吸附测定法检测血清激素水平,免疫荧光染色检测颗粒细胞中亲吻素(Kp)、G蛋白偶联受体54(GPR54)荧光强度,实时定量反转录聚合酶链式反应检测颗粒细胞中Kiss-1、GPR54基因表达。结果与正常对照组比较,模型组大鼠卵巢囊状扩张卵泡及闭锁卵泡增加,卵泡颗粒细胞层变薄;卵巢指数增大[(1.22±0.10)mg/g比(0.82±0.13)mg/g,P<0.05];血清黄体生成素[(66.32±3.98)IU/L比(11.87±5.54)IU/L]、睾酮[(33.72±3.57)ng/mL比(8.40±2.94)ng/mL]、Kp水平[(1506.79±154.82)pg/mL比(289.57±89.20)pg/mL]均升高(P<0.05);卵巢颗粒细胞中Kp荧光强度[(1601852.67±378567.82)比(3685156.00±359825.63)]、GPR54荧光强度[(1298372.25±297701.61)比(2961456.58±309119.01)]及Kiss-1基因表达[(0.10±0.03)比(1.11±0.14)]、GPR54基因表达[(0.10±0.05)比(1.00±0.13)]均降低(P<0.05)。结论卵巢表达的Kiss-1/GPR54系统可能通过调节颗粒细胞从而影响PCOS大鼠卵泡发育。

糖宁孜亚比土斯片基于高糖人结直肠腺癌细胞模型对小克里斯滕森菌-TαMCA-FXR/TGR5轴的调控作用

目的探讨糖宁孜亚比土斯片(TZT)基于高糖人结直肠腺癌细胞模型对小克里斯滕森菌科-牛磺-α鼠胆酸钠盐(TαMCA)-法尼醇X受体(FXR)/G蛋白偶联受体5轴的调控作用。方法配制菌株液体培养基、高糖培养基、TZT溶液、TαMCA溶液,培养菌株,制备灭活小克里斯滕森菌及其发酵液,常规培养人结直肠腺癌细胞(Caco-2细胞)。取部分细胞随机分为对照组、灭活菌体组、106 CFU/mL活菌组、10^(7)CFU/mL活菌组、10^(8)CFU/mL活菌组、10^(9)CFU/mL活菌组,对照组用无菌Caco-2专用培养基培养,灭活菌体组用灭活小克里斯滕森菌菌体悬液干预,106 CFU/mL活菌组、10^(7)CFU/mL活菌组、10^(8)CFU/mL活菌组、10^(9)CFU/mL活菌组分别在含有完全分化的Caco-2细胞培养板孔中加入2 mL 10^(9)CFU、10^(8)CFU、10^(7)CFU、10^(6)CFU的小克里斯滕森菌活菌干预。取部分细胞随机分为对照组、发酵培养液组,对照组用无菌Caco-2专用培养基培养,发酵培养液组用小克里斯滕森菌发酵液干预。取部分细胞随机分为对照组、高糖组及TZT低、中、中高、高剂量组,除对照组外其他各组加入8 g/L高糖培养基干预24 h,TZT低、中、中高、高剂量组分别加入10、25、50、100μg/mL的TZT含药培养基干预24 h。取部分细胞随机分为对照组、25μmol/L TαMCA组、50μmol/L TαMCA组,后两组换入25、50μmol/L的含TαMCA培养基干预24 h。实时荧光定量PCR法检测FXR、TGR5、IL-8、IL-10 mRNA,Western blotting法检测FXR、TGR5蛋白。结果与对照组比较,10^(6)CFU/mL活菌组、10^(7)CFU/mL活菌组、10^(8)CFU/mL活菌组、10^(9)CFU/mL活菌组TGR5 mRNA表达高(P均<0.05),FXR、IL-8、IL-10 mRNA表达差异无统计学意义(P均>0.05)。与对照组比较,菌发酵液组FXR mRNA表达高(P均<0.05),TGR5 mRNA表达差异无统计学意义(P均>0.05)。与对照组比较,高糖组FXR mRNA表达高(P<0.05),TGR5 mRNA表达低(P<0.05),FXR、TGR5蛋白表达差异无统计学意义(P均>0.05)。与高糖组比较,各TZT组FXR mRNA表达低(P均<0.05),TGR5 mRNA表达高(P均<0.05),FXR、TGR5蛋白表达差异无统计学意义(P均>0.05)。与对照组比较,25μmol/L TαMCA组FXR mRNA、蛋白表达低(P均<0.05),TGR5 mRNA、蛋白表达高(P均<0.05);50μmol/L TαMCA组FXR蛋白表达低(P<0.05)。结论小克里斯滕森菌具有一定的抗炎效果,TZT可能通过促进小克里斯滕森菌的生长,产生代谢产物影响胆汁酸代谢,促进TαMCA肠道内累积,进一步抑制肠FXR表达,促进TGR5表达。

Physiological and pharmacological functions of G protein coupled receptor 124:A review

G protein-coupled receptors(GPCRs)are the largest protein superfamily in the body,expressed in various tissues and organs,and are currently one of the most important clinical drug targets.Recently,a class of GPCRs without endogenous ligands(orphan GPCRs)have been discovered.They exhibit different physiological functions in the body and act extensively on the cardiovascular and cerebrovascular systems.Among them,G protein-coupled receptor 124(GPR124)is an orphaned member of the G protein coupled receptor adhesion family that has attracted much attention.It plays a key role in promoting cerebral angiogenesis and maintaining the stability of the blood-brain barrier.It also associated with cardiovascular and cerebrovascular diseases such as cerebral ischemia and atherosclerosis.However,the role of GPR124 in these diseases,the associated signaling pathways,and possible drug intervention targets are still unclear.This article summarizes the physiological effects,pharmacological effects and related signal pathways of GPR124 published in the field of cardiovascular and cerebrovascular diseases published in recent years,in order to provide a reference for the study of the role of GPR124 in the occurrence and development of diseases.

GPR120激动剂通过β-Arrestin2途径改善高糖诱导的海绵体内皮细胞功能障碍

目的探讨激活G蛋白偶联受体(GPR)120对高糖诱导的人类阴茎海绵体内皮损伤修复的影响,以期为寻找糖尿病性勃起功能障碍(DMED)新的药物开发靶点提供理论依据。方法收集海绵体植入手术患者术中废弃海绵体组织提取海绵体内皮细胞进行原代培养,用高浓度葡萄糖诱导内皮细胞损伤,再以GPR120激动剂治疗,观察对比不同处理的细胞一氧化氮(NO)释放量、细胞迁移、血管生成等功能。结果成功提取人类海绵体内皮细胞进行原代培养并鉴定;发现GPR120在人类海绵体内皮细胞中稳定表达,且与内皮型一氧化氮合酶(eNOS)存在共定位;与高糖损伤组相比,GPR120激动剂治疗组NO释放量、划痕愈合率和血管生成率均显著增加(P<0.05);沉默β-Arrestin2后GPR120激动剂失去原有的治疗效果。结论高糖培养可诱导海绵体内皮细胞功能障碍,GPR120激动剂能够治疗海绵体内皮功能障碍,沉默β-Arrestin2后GPR120激动剂无法改善内皮功能。

血清sMICA、PCNA、GASP-1、TIMP-1在非小细胞肺癌患者中的表达及相关性分析

目的探讨血清可溶性MHC-I类链相关蛋白A(sMICA)、增殖细胞核抗原(PCNA)、G蛋白偶联受体相关分选蛋白1(GASP-1)、组织金属蛋白酶抑制剂1(TIMP-1)在非小细胞肺癌(NSCLC)患者中的表达及与病理分型的相关性。方法2020年7月至2022年8月诊治的86例NSCLC患者作为研究对象,并设立为观察组,同期选取43例健康体检者设立为对照组;并根据不同病理分型将观察组分为腺癌组(n=33)和鳞癌组(n=53),对比血清sMICA、PCNA、GASP-1、TIMP-1;并采用Logistic回归模型分析sMICA、PCNA、GASP-1、TIMP-1对非小细胞肺癌的影响;采用ROC曲线模型分析sMICA、PCNA、GASP-1、TIMP-1诊断非小细胞肺癌的AUC、敏感度及特异度。结果观察组的sMICA、PCNA、GASP-1、TIMP-1均高于对照组(P<0.05)。腺癌组的sMICA、PCNA、GASP-1、TIMP-1均高于鳞癌组(P<0.05)。二元Logistic回归模型分析显示,sMICA、PCNA、GASP-1、TIMP-1高表达会对非小细胞肺癌的发生产生影响(P<0.05)。ROC曲线分析显示,sMICA、PCNA、GASP-1、TIMP-1及四项联合诊断NSCLC的AUC值分别为(0.750、0.654、0.819、0.788、0.843,P均<0.05),敏感度分别为57.00%、46.50%、67.40%、90.70%、79.10%;特异度分别为93.00%、93.00%、88.40%、58.10%、86.00%。结论sMICA、PCNA、GASP-1、TIMP-1在NSCLC患者中呈高表达趋势,其表达水平会随病理分型而升高。

Rspo3/Lgr5促进N-钙黏蛋白表达参与小鼠肝损伤

目的本文旨在研究在损伤肝组织中,特异性顶部盘状底板反应蛋白3(R-spondin3,Rspo3)上调周细胞N-钙黏蛋白(N-cadherin,Ncad,基因名Cdh2)表达,从而参与小鼠肝损伤。方法采用反转录实时定量聚合酶链反应法(reverse transcription-quantitative polymerase chain reaction,RT-qPCR)测定Rspo3,小鼠肝组织富含亮氨酸重复序列G蛋白偶联受体5(leucine-rich repeat-containing G protein-coupled receptor 5,Lgr5)和Cdh2 mRNA表达情况;采用蛋白质免疫印迹方法以及免疫荧光染色方法测定Ncad定位以及表达情况;分离并培养小鼠原代骨髓间充质细胞(bone marrow mesenchymal stromal cell,BMSC),采用靶向Lgr5的RNA干扰实验以确定Rspo3是否通过作用于Lgr5上调Ncad表达。结果在损伤小鼠肝组织中,Rspo3及其受体Lgr5显著上调;肝损伤时黏附连接蛋白Ncad表达上调,且与Rspo3及Lgr5表达量呈正相关;Ncad主要定位于损伤肝脏的周细胞;使用Rspo3处理小鼠原代BMSC能够上调Ncad表达,Lgr5 siRNA能使Ncad水平下降。结论在小鼠损伤肝组织中,Rspo3通过作用于受体Lgr5,上调周细胞中Ncad表达,从而影响小鼠肝损伤。

20-HETE通过GPR75受体偶联G_(αq)信号通路诱导H9c2心肌细胞凋亡的作用

目的 探讨GPR75受体偶联G_(αq)信号通路在20-HETE诱导的H9c2心肌细胞凋亡中的作用与机制。方法 H9c2心肌细胞采用慢病毒载体干扰GPR75表达,敲减效率通过RT-qPCR和Western blot法检测;ELISA法检测IP_(3)及cAMP含量;TUNEL法评估细胞凋亡率;分别使用Fluo-4/AM、DHE和JC-1荧光探针检测细胞内Ca^(2+)浓度、ROS含量以及线粒体膜电位(ΔΨm)水平;Western blot检测EGFR、ERK1/2、AKT、GSK3β、Bax、Bcl-2、Cyt C、Caspase-3蛋白表达。结果 慢病毒载体shGPR75转染后,H9c2心肌细胞GPR75受体mRNA和蛋白表达分别降低67.16%和63.99%(P<0.05)。敲减GPR75表达或应用AAA阻断其作用,显著抑制20-HETE诱导的H9c2心肌细胞凋亡(P<0.05),并可逆转ΔΨm下降及凋亡相关蛋白Bax、Cyt C、Caspase-3蛋白表达增高(P<0.05)。20-HETE处理后细胞内IP_(3)含量明显增加(P<0.05),但对cAMP生成无显著影响(P>0.05),而敲减GPR75表达、应用AAA或者PLC信号通路阻断剂U73122预处理后,可显著阻断细胞内IP_(3)生成(P<0.05)。敲减GPR75表达、应用AAA或者U73122预处理后,明显抑制20-HETE诱导的Ca^(2+)浓度升高和ROS生成效应(P<0.05)。20-HETE处理后,GPR75受体下游调控关键蛋白EGFR、ERK1/2、AKT、GSK3β磷酸化水平明显升高(P<0.05),敲减GPR75表达或应用AAA可有效阻断20-HETE上述效应(P<0.05)。最后,阻断PLC或PI3K信号通路,显著抑制20-HETE诱导的心肌细胞凋亡(P<0.05)。结论 20-HETE通过GPR75受体偶联的G_(αq)蛋白及其介导的PLC、EGFR/ERK1/2/AKT/GSK3β信号通路诱导H9c2心肌细胞凋亡。

肺癌患者GASP-1、LCN2和TPX2的表达水平及其与TNM分期和预后的相关性分析

目的探究肺癌患者血清G蛋白偶联受体相关分选蛋白1(GASP-1)、脂质运载蛋白-2(LCN2)、Xklp2靶蛋白(TPX2)表达水平及其与TNM分期和预后的相关性。方法选取2019年4月至2022年5月在南部战区总医院接受诊疗的92例肺癌患者作为观察组,同期选取92例健康体检者作为对照组。采集所有研究对象的外周静脉血样,检测血清GASP-1、LCN2、TPX2表达水平。将观察组按预后情况分为预后良好组和预后不佳组,比较2组患者血清GASP-1、LCN2、TPX2表达水平。分析肺癌患者血清GASP-1、LCN2、TPX2表达水平与TNM分期和预后的相关性。结果观察组血清GASP-1、LCN2、TPX2表达水平高于对照组(P<0.05);观察组TNM分期为Ⅲ、Ⅳ期的肺癌患者血清GASP-1、LCN2、TPX2表达水平高于TNM分期为Ⅰ、Ⅱ期的肺癌患者(P<0.05),TNM分期为Ⅳ期的患者血清GASP-1、LCN2、TPX2表达水平均高于TNM分期为Ⅲ期的患者(P<0.05)。预后良好组血清GASP-1、LCN2、TPX2水平均低于预后不佳组(P<0.05);观察组治疗前血清GASP-1、LCN2、TPX2表达水平均与TNM分期呈正相关(P<0.05),治疗后血清GASP-1、LCN2、TPX2表达水平均与预后呈负相关(P<0.05)。结论血清GASP-1、LCN2、TPX2表达水平与肺癌患者的TNM分期相关,在对症治疗后检测上述血清指标,可在一定程度上反映患者预后情况,为临床提供参考。