Mammalian oocytes within Graafian follicles are arrested at prophase I of meiosis. C-type natriuretic peptide (NPPC), secreted by mural granulosa cells (MGCs), maintains oocyte meiotic arrest via binding to its cognate receptor natriuretic peptide receptor 2 (NPR2) and producing cyclic guanosine monophosphate (cGMP). NPR2 is most concentrated in the cumulus cells. In addition, cAMP, gap junction, inosine monophosphate dehydrogenase (IMPDH) and other important regulatory factors are also involved in meiotic arrest. Luteinizing hormone (LH) then rapidly decreases cGMP and induces oocyte meiotic resumption. In this paper, advances in the molecular mechanisms of meiotic arrest and LH-induced meiotic resumption were reviewed. This paper may provide new ideas for the prevention, diagnosis and treatment of related reproductive diseases.
Animals ; Cumulus Cells ; Female ; Luteinizing Hormone ; Meiosis ; Natriuretic Peptide, C-Type ; genetics ; Oocytes

This study aimed to explore the role of miR-130a-3p in cardiomyocyte hypertrophy and its underlying mechanisms. Pressure-overload induced myocardial hypertrophy mice model was constructed by thoracic aortic constriction (TAC). , norepinephrine (NE) was used to stimulate neonatal rat cardiomyocytes (NRCMs) and H9c2 rat cardiomyocytes to induce hypertrophic phenotypes. The expression of miR-130a-3p was detected in mice hypertrophic myocardium, hypertrophic NRCMs and H9c2 cells. The mimics and inhibitors of miR-130a-3p were transfected into H9c2 cells to observe the role of miR-130a-3p on the hypertrophic phenotype change of cardiomyocytes separately. Furthermore, whether miR-130a-3p regulated hypertrophic related signaling pathways was explored. The results showed that the expression of miR-130a-3p was significantly decreased in hypertrophic myocardium, hypertrophic NRCMs and H9c2 cells. After transfection of miR-130a-3p mimics, the expression of hypertrophic marker genes, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and β-myosin heavy chain (β-MHC), and the cell surface area were notably down-regulated compared with the control group (mimics N.C. + NE group). But after transfection of miR-130a-3p inhibitor, the expression of ANP, BNP and β-MHC in H9c2 cells increased significantly, and the cell area increased further. By Western blot, it was found that the protein phosphorylation level of Akt and mTOR were down-regulated after over-expression of miR-130a-3p. These results suggest that miR-130a-3p mimics may alleviate the degree of cardiomyocyte hypertrophy, meanwhile its inhibitor can further aggravate cardiomyocyte hypertrophy. Over-expression of miR-130a-3p may attenuate cardiomyocytes hypertrophy by affecting the Akt pathway.
Animals ; Atrial Natriuretic Factor ; Cardiomegaly ; Mice ; MicroRNAs ; genetics ; Myocardium ; pathology ; Myocytes, Cardiac ; pathology ; Myosin Heavy Chains ; Natriuretic Peptide, Brain ; Nonmuscle Myosin Type IIB ; Proto-Oncogene Proteins c-akt ; Rats

PURPOSE: This study investigated the role of natriuretic peptide receptor 2 (NPR2) on cell proliferation and testosterone secretion in mouse Leydig cells. MATERIALS AND METHODS: Mouse testis of different postnatal stages was isolated to detect the expression C-type natriuretic peptide (CNP) and its receptor NPR2 by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Leydig cells isolated from mouse testis were cultured and treated with shNPR2 lentiviruses or CNP. And then the cyclic guanosine monophosphate production, testosterone secretion, cell proliferation, cell cycle and cell apoptosis in mouse Leydig cells were analyzed by ELISA, RT-qPCR, Cell Counting Kit-8, and flow cytometry. Moreover, the expression of NPR2, cell cycle, apoptosis proliferation and cell cycle related gene were detected by RT-qPCR and Western blot. RESULTS: Knockdown of NPR2 by RNAi resulted in S phase cell cycle arrest, cell apoptosis, and decreased testosterone secretion in mouse Leydig cells. CONCLUSIONS: Our study provides more evidences to better understand the function of CNP/NPR2 pathway in male reproduction, which may help us to treat male infertility.
Animals ; Apoptosis ; Blotting, Western ; Cell Count ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Proliferation ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Germ Cells ; Guanosine Monophosphate ; Humans ; Infertility, Male ; Lentivirus ; Leydig Cells ; Male ; Mice ; Natriuretic Peptide, C-Type ; Polymerase Chain Reaction ; Receptors, Peptide ; Reproduction ; Reverse Transcription ; RNA Interference ; S Phase ; Testicular Diseases ; Testis ; Testosterone

OBJECTIVETo analyze the effects of acupuncture on the level of atrial natriuretic peptide (ANP), C-type natriuretic peptide (CNP) in adrenal gland and the content of corticosterone (CORT) in plasma in rats withchronic emotional stress anxiety, and to explore the partial action mechanism of acupuncture on anxiety disorder.

METHODSThirty-two healthy Sprague-Dawley (SD) rats, after 7 days of feeding and domestication, were randomly divided into a blank group (10 rats), a model group (11 rats) and an acupuncture group (11 rats). The rats inthe model group and acupuncture group were treated with unpredictable chronic emotional stress (CES) method toestablish the model of anxiety. Rats in the acupuncture group were treated with acupuncture at "Neiguan" (PC 6)and "Shenmen" (HT 7), once every other day, 30 minutes each time. The model establishment and treatment lasted 15 days. Rats in the blank group were treated with identical immobilization but no treatment was given. Theelevated plus maze was used to test the behavioral changes of rats with anxiety; the level of CORT in plasma wasdetected by ELISA, and the expression level of CNP and ANP in adrenal cortex and medulla was detected by immunohistochemical method.

RESULTS(1) The percentage of open-arms time in total time (OT%) in elevated plus maze in the model group was significantly lower than that in the blank group (P<0. 05); the OT% in the acupuncture group was significantly higher than that in the model group (P<0.01). (2) The content of CORT in plasma in the model group was higher than that in the blank group (P<0. 05), while that in the acupuncture group was significantly lower than that in the model group (P<0. 05). (3) The expression of ANP in adrenal medulla and cortex in the model group was lower than that in the blank group (P<0. 01), while the expression of CNP in adrenal medulla and cortex in the model group was higher than that in the blank group (P<0. 01).

CONCLUSIONThe effects of acupuncture against anxiety are likely to be related to the regulation on the expression of ANP and CNP in adrenal medulla, affecting the release of CORT and inhibition on the activity !f hypothalamic-pituitary-adrenal axis (HPA axis).

Acupuncture Therapy ; Adrenal Glands ; metabolism ; Animals ; Anxiety ; blood ; psychology ; therapy ; Atrial Natriuretic Factor ; blood ; metabolism ; Behavior, Animal ; Corticosterone ; blood ; Humans ; Male ; Natriuretic Peptide, C-Type ; blood ; metabolism ; Rats ; Rats, Sprague-Dawley ; Stress, Psychological

Cardiovascular Diseases ; Humans ; Natriuretic Peptide, C-Type

OBJECTIVETo investigate the effect of estrogen on cell proliferation and expression of proteins of C-type natriuretic peptide (CNP), natriuretic peptides B receptor (NPR-B) and natriuretic peptides C receptor (NPR-C) in ATDC5 cells during chondrogenesis.

METHODATDC5 cells were induced for differentiation with insulin 10 µg/ml (day 0), and were started to be investigated on day 6. They were incubated with: (1) Estradiol (E2) at different concentrations (10(-11)-10(-5) mol/L) for 24 hours (for studying cell proliferation), or for 48 hours (for studying CNP, NPR-B and NPR-C protein expression); (2) E2 (10(-8) mol/L) for 24, 48, 72, 96 and 120 h (for studying cell proliferation), or for 24, 48, 72 and 96 hours (for studying CNP, NPR-B and NPR-C protein expression); (3) E2 (10(-8) mol/L) , and/or ICI 182782 (estrogen receptor antagonist ) (10(-7) mol/L) for 24 hours (for studying cell proliferation). ATDC5 cells proliferation were determined by MTT (OD value). Western-blotting was performed to identify the protein levels of CNP, NPR-B and NPR-C.

RESULT(1) After incubation with E2 (10(-11)-10(-5) mol/L) for 24 h, ATD5 cell number increased with the increasing E2 concentration, peak in E2 concentrations of 10(-9) and 10(-8) mol/L (0.56 ± 0.06 and 0.52 ± 0.02, P < 0.05 and <0.01, respectively) , while significantly decreased in E2 (10(-5) mol/L) (0.30 ± 0.02) compared with DMSO-control (0.38 ± 0.02) (P < 0.05). After incubation with E2 (10(-11)-10(-5) mol/L) for 48 h, the protein level of CNP, NPR-B and NPR-C increased significantly, with the greatest effect seen at a concentration of 10(-10) mol/L E2 for CNP and NPR-B, 10(-9) mol/L E2 for NPR-C (P < 0.05). (2) After incubation with E2 (10(-8) mol/L) for 24 to 96 hours: (1) The cell number in each of the four time points was significantly increased compared with DMSO-control, with the greatest effect in 48 h (0.030 ± 0.003) (P < 0.05 or <0.01, respectively). While the cell number at 120 h was similar to that in DMSO-control. (2) The protein level of CNP increased significantly at 24 h (P < 0.05), seemed to be increased at 48 h and 72 h and decreased at 96 h. Both NPR-B and NPR-C level seemed to be increased at 24 h (P = 0.060 and 0.055, respectively) and seemed to decrease at 48 h, with decreasing significantly at both 72 h and 96 h (P < 0.05). (3) After incubation for 24 h, there was significant difference among the cell number of the four groups (P < 0.05). Cell number of group E2 (0.470 ± 0.032) was increased compared with group (E2+ICI) (0.410 ± 0.018), both being increased compared with group DMSO-control (0.370 ± 0.011, P < 0.05, respectively). There was no difference in cell number between group ICI 182782(0.360 ± 0.035) and group DMSO-control.

CONCLUSIONE2 promotes the proliferation of ATDC5 cells i.e. chondrogenesis via estrogen receptor mediated mechanism, in both concentration-dependent and time-dependent manner. E2 (10(-11)-10(-8) mol/L) up-regulates protein expression of CNP, NPR-B and NPR-C of ATDC5 cells during chondrogenesis, and regulate the expression of the three proteins mentioned above positively or negatively at different time point, which implied that estrogen is one of the regulators of CNP signaling pathway.

Animals ; Blotting, Western ; Cell Differentiation ; drug effects ; Cell Line ; Cell Proliferation ; drug effects ; Chondrogenesis ; Dose-Response Relationship, Drug ; Estradiol ; pharmacology ; Gene Expression Regulation ; drug effects ; Mice ; Natriuretic Peptide, C-Type ; metabolism ; Receptors, Atrial Natriuretic Factor ; metabolism ; Signal Transduction ; drug effects ; Time Factors

BACKGROUND AND OBJECTIVES: The purpose of this study was to assess the value of C-type natriuretic peptide (CNP) as a surrogate marker for detection of coronary artery spasm in variant angina pectoris (VAP). SUBJECTS AND METHODS: Sixty-six patients (mean age: 51+/-11 years, M : F=40 : 26) who underwent coronary angiography on suspicion of angina and who were diagnosed with VAP by the acetylcholine-induced spasm provocation test (SPT) were enrolled and divided into a SPT (-) group (n=23) and a SPT (+) group (n=43). Concentrations of CNP and other markers were determined by immunoassay in both groups. RESULTS: Plasma CNP and creatine kinase myoglobin band (CK-MB) concentrations were significantly increased in the SPT (+) group relative to the SPT (-) group (CNP, 5.268+/-1.800 pg/mL vs. 3.342+/-1.150 pg/mL, p=0.002; CK-MB, 2.54+/-1.03 ng/dL vs. 1.86+/-0.96 ng/dL, p=0.019, respectively) while plasma high sensitivity C-reactive protein (hs-CRP) and N-terminal pro-brain natriuretic peptide (NT pro-BNP) concentrations were not significantly different between the SPT (-) group and SPT (+) group (hs-CRP, 2.76+/-4.99 mg/L vs. 3.13+/-4.88 mg/L, p=0.789; NT pro-BNP, 49+/-47 pg/mL vs. 57+/-63 pg/mL, p=0.818, respectively). Plasma CNP concentration was independently associated with the VAP via SPT {odds ratio: 2.014 (95% confidence interval: 1.016-3.992), p=0.045}. A CNP cut-off value of 4.096 pg/mL was found to have a sensitivity of 68.2% and a specificity of 40.0% for predicting the probability of VAP via SPT. CONCLUSION: Increased plasma CNP concentration in patients with VAP may have an impact on the regulation of endothelial function in accordance with the progression of atherosclerosis. Further analysis is warranted to develop clinical applications of this finding.
Acetylcholine ; Angina Pectoris, Variant ; Atherosclerosis ; Biomarkers ; C-Reactive Protein ; Coronary Angiography ; Coronary Vessels ; Creatine Kinase ; Endothelium ; Humans ; Immunoassay ; Myoglobin ; Natriuretic Peptide, C-Type ; Plasma ; Sensitivity and Specificity ; Spasm

OBJECTIVETo investigate the expression of C-type natriuretic peptides (CNP) and natriuretic peptide receptor-B (NPR-B) receptor in diabetic rats renal cortex, and the regulation by Tongluo Recipe (TLR).

METHODSSixty male SD rats were divided into 3 groups: the normal control group, diabetic model group and diabetic TLR group. Each group was further divided into two subgroups of ten in each, according to 4-week or 12-week observation period. Streptozotocin (STZ)-induced diabetic rats were treated with TLR (1.0 g·kg(-1)·d(-1)) for 4 and 12 weeks, respectively. (1) The essential information was collected for comparing renal mass, serum creatinine and 24 h urine albumen on each group was calculated. (2) CNP mRNA and NPR-B mRNA were detected by realtime-polymerase chain reaction (PCR) on rats renal cortex. (3) Concentration of CNP on renal cortex or serum were analyzed by enzyme-linked immunosorbent assay (ELISA). (4) Pathological evaluation and NPR-B immunostaining for renal tissue were also performed.

RESULTS(1) CNP and NPR-B mRNA levels were detected in each treated or untreated group, with slight elevated in untreated diabetes rats administrated with STZ after 4-week and CNP mRNA level remarkable elevated at 39.21 times higher than normal control group after 12 weeks, but NPR-B mRNA level showed a remarkably down-regulation at 98.07% after 12 weeks. CNP mRNA of TLR-treated group was also elevated after 12-week treatment, but less than untreated group. (2) Concentrations of CNP in renal cortex were obviously increased in treated or untreated diabetes rats, within these groups the treatment of TLR was found more significantly on prompting CNP concentration. Comparing to normal group, serum concentrations of CNP were also increased in treated or untreated diabetic groups, but there was no difference between these diabetic groups. (3) Renal lesions like glomerular volume increased are observed mostly in the relative early stage after 4 weeks. Although TLR treated group had no significant difference in their glomerular volume, the degrees of injury of glomerulus were ameliorated, as well as the NPR-B immunostaining enhanced in glomerulus. Weakly positive immunostaining of NPR-B are observed in glomerulus of normal control, and negative in glomerulus of untreated diabetes rats administrated with STZ after 12 weeks, whereas TLR-treatment groups showed a little enhancement.

CONCLUSIONCNP and NPR-B showed different characteristic on renal cortex at different pathological period in diabetes rats, and TLR regulated their expression.

Animals ; Body Weight ; drug effects ; Diabetes Mellitus, Experimental ; complications ; drug therapy ; genetics ; pathology ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Gene Expression Regulation ; drug effects ; Hematuria ; complications ; genetics ; pathology ; Immunohistochemistry ; Kidney ; drug effects ; metabolism ; pathology ; Kidney Cortex ; drug effects ; metabolism ; pathology ; Kidney Glomerulus ; drug effects ; metabolism ; pathology ; Male ; Natriuretic Peptide, C-Type ; genetics ; metabolism ; Organ Size ; drug effects ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Atrial Natriuretic Factor ; genetics ; metabolism ; Staining and Labeling ; Streptozocin

The natriuretic peptides are a family of three peptides, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP). CNP is produced in the growth plate and acts in a paracrine/autocrine manner and has been found to play an essential role in enchondral bone growth , as demonstrated in rodents and human. Biosynthetic processing of CNP releases a bioinactive amino-terminal propeptide of C-type natriuretic peptide (NTproCNP) and is produced in equimolar amounts with CNP. The level of NTproCNP in plasma reflects the rate of CNP biosynthesis and measured easily using commercial kit by enzyme-linked immunosorbent assay (ELISA) method. Knockout mice for CNP or its cognate receptor (NPR-B) are dwarfed. In human, homozygous loss of functional mutations in the NPR-B gene causes acromesomelic dysplasia, Maroteaux type (OMIM #602875). To clarify the role of CNP/NTproCNP in linear growth in human, some researchers measured plasma NTproCNP levels in healthy children and children with short stature due to various causes. CNP showed the heighest levels after 12 hr of life and with a progressive decline afterwards. It is proved that there is modest but significant correlation between NTproCNP level and IGF-I in healthy children and the timing of peaks in NTproCNP and IGF-I were identical in both sex. This paper will introduce recent advances of researches concerning about the role of CNP/NTproCNP in human growth in children with various conditions and suggest the future direction of this promising study field.
Animals ; Atrial Natriuretic Factor ; Bone Development ; Bone Diseases, Developmental ; Child ; Enzyme-Linked Immunosorbent Assay ; Growth Plate ; Humans ; Insulin-Like Growth Factor I ; Mice ; Mice, Knockout ; Natriuretic Peptide, Brain ; Natriuretic Peptide, C-Type ; Natriuretic Peptides ; Plasma ; Rodentia

There are many established and proposed bio-molecular markers for cardiovascular disease, including vasoactive substances, substances related to inflammation and oxidative stress, and substances involved in tissue structure and remodeling. Among these substances, we focused on natriuretic peptides and adrenomedullin (AM) as clinically useful bio-molecular markers in this review. Three natriuretic peptides-atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP)-play various important roles in the cardiovascular system. ANP and BNP are released from the heart and exist primarily as circulating hormones. They participate in the regulation of blood pressure and fluid levels. Plasma levels of ANP and BNP are increased in various pathological conditions such as heart failure, myocardial infarction, and hypertension with cardiac hypertrophy. BNP is now essential as a biochemical marker in managing patients with cardiovascular disease. CNP is mainly produced in vascular endothelium. It contributes to smooth muscle relaxation and growth inhibition as a local hormone, but it is also synthesized in cardiac fibroblasts and inhibits fibroblast proliferation and myocyte growth. However, the significance of plasma CNP levels remains to be elucidated. AM is widely distributed in various organs and tissues, including the cardiovascular system. Not only it is a potent vasodilator peptide, but it also has protective effects against vascular and cardiac cell injury and excessive growth. Plasma AM levels are increased in several cardiovascular diseases, including hypertension, heart failure, myocardial infarction, and atherosclerotic disease, and AM appears to be a predictive and prognostic marker in the setting of cardiovascular disease.
Adrenomedullin ; Atherosclerosis ; Atrial Natriuretic Factor ; Biomarkers ; Blood Pressure ; Cardiomegaly ; Cardiovascular Diseases ; Cardiovascular System ; Endothelium, Vascular ; Fibroblasts ; Heart ; Heart Failure ; Humans ; Hypertension ; Inflammation ; Muscle Cells ; Muscle, Smooth ; Myocardial Infarction ; Natriuretic Peptide, Brain ; Natriuretic Peptide, C-Type ; Natriuretic Peptides ; Oxidative Stress ; Plasma ; Relaxation