MicroRNA-29c-3p in dual-labeled exosome is a potential diagnostic marker of subjective cognitive decline.

OBJECTIVE: The present study aimed to determine whether peripheral blood neural cell adhesion molecule (NCAM)/amphiphysin 1 dual-labeled exosomal proteins and microRNAs (miRs) might serve as a marker for the early diagnosis of Alzheimer's disease (AD). METHODS: This observational, retrospective, multicenter study used a two-stage design conducted in Beijing and Shanghai, China. The subjects included 76 patients with subjective cognitive decline (SCD), 80 with amnestic mild cognitive impairment (aMCI), 76 with dementia of Alzheimer's type (AD), 40 with vascular dementia (VaD), and 40 controls in the discovery stage. These results were confirmed in the verification stage. The levels of Aß42, Aß42/40, T-Tau, P-T181-tau, neurofilament light chain (NfL), and miR-29c-3p in peripheral blood amphiphysin 1 single-labeled and NCAM/amphiphysin 1 dual-labeled exosomes were captured and detected by immunoassay. RESULTS: In the discovery stage, the levels of Aß42 and miR-29c-3p in peripheral blood NCAM/amphiphysin 1 dual-labeled exosome of the SCD group were significantly higher than those in control and VaD groups (all P < 0.05). The verification stage further confirmed the results of the discovery stage. Plasma NCAM/amphiphysin 1 dual-labeled exosomal miR-29c-3p showed a good diagnostic performance. The NCAM/amphiphysin 1 dual-labeled exosomal miR-29c-3p had the highest AUC for diagnosis of SCD. The levels of Aß42, Aß42/40, Tau, P-T181-tau, and miR-29c-3p in peripheral blood exosomes were correlated to those in CSF (all P < 0.05). The combination of exosomal biomarkers had slightly higher diagnostic efficiency than the individual biomarkers and that the exosomal biomarkers had the same diagnostic power as the CSF biomarkers. CONCLUSION: The plasma NCAM/amphiphysin 1 dual-labeled exosomal miR-29c-3p had potential advantages in the diagnosis of SCD.

Severely High Lactic Acid in Severe Pneumonia Patient: a Case Report.

BACKGROUND: Severe pneumonia (SP) is a clinically critical acute disease which has a higher mortality rate among infectious diseases. In this report, a rare case of severe pneumonia with severely high lactic acid (up to 24 mmol/L) and relatively normal pH was analyzed. METHODS: The case was discussed from different angles including acid-base balance disorder, the use of extractor-poreal membrane oxygenation (ECMO), dialysis treatment, circulatory disturbance, and inspection methodology. RESULTS: Hypoxia and dissolution of muscles caused by circulatory disorders may be the cause of the abnormal increase of lactate in this case; while the relatively normal pH may be caused by the dialysis treatment. CONCLUSIONS: Such a high blood gas lactic acid value is extremely rare, and this increase is not due to the limitations of the test method. High lactic acid may not result in the significant decrease of pH when the patient receives continuous systemic treatment.

Human POLD1 modulates cell cycle progression and DNA damage repair.

BACKGROUND: The activity of eukaryotic DNA polymerase delta (Pol δ) plays an essential role in genome stability through its effects on DNA replication and repair. The p125 catalytic subunit of Pol δ is encoded by POLD1 gene in human cells. To clarify biological functions of POLD1, we investigated the effects of POLD1 overexpression or downregulation on cell proliferation, cell cycle progression, DNA synthesis and oxidative DNA damage induced by H2O2. METHODS: HEK293 cells were transfected with POLD1 expression plasmid or shRNA, cell proliferation, cell cycle progression, and DNA synthesis in HEK293 cells were analyzed. RESULTS: HEK293 cells were transfected with POLD1 expression plasmid or shRNA. POLD1 downregulation by shRNA suppressed cell proliferation, cell cycle progression, and DNA synthesis in HEK293 cells. However, POLD1 overexpression had no significant effects on these processes. Finally, comet assay showed that POLD1 downregulation led to increased DNA damage. CONCLUSIONS: Our results suggest that human POLD1 plays important role in the regulation of cell cycle progression and DNA damage repair.

A brief history of clozapine in China with a look forward.

Clozapine was first manufactured in China in 1976. Clozapine is currently used not only for treatment-refractory schizophrenia (TRS), but also continues to be used in the treatment of patients with non-TRS and other mental disorders; moreover, low-dose clozapine is also used in sedative-hypnotic therapy and in combination with other drugs. There is need for studies in China using various titrations and assessing their risk for myocarditis and aspiration pneumonia. The Chinese clozapine package insert will also greatly benefit from these changes.

Age-dependent down-regulation of DNA polymerase δ1 in human lymphocytes.

Aging progress and degeneracy of functional activity are mainly attributed to the decreased DNA repair potential. DNA polymerase (pol) δ activity plays an essential role in genome stability by virtue of its crucial DNA replication and repair capacity. To order to clarify the role of DNA pol δ in aging progression, we firstly examined the expressions of its catalytic subunit named DNA pol δ1 in human lymphocytes at different age stages, respectively, and then observed the effect of diseases on DNA pol δ1 in vivo and of nutriture on its expressions in 2BS cells in vitro. Blood samples from the healthy subjects and patients with diabetes mellitus and coronary heart disease were collected, respectively, for analysis of transcription and protein expressions of DNA pol δ1 by RT-PCR and western blot. 2BS cells of PD30 and PD47 were incubated in both normal medium and other mediums of different nutritures for verifying the differential expressions of DNA pol δ1. Results showed that the mRNA expression of DNA pol δ1 decreased substantially with age and the protein levels were well consistent with gene levels. Furthermore, there were no significant differences in DNA pol δ1 expressions between the groups of healthy individuals and the age matched patients. In addition, DNA pol δ1 gene expression levels were not affected by nutritional status in vitro. Our findings collectively confirmed that the down-regulations of DNA pol δ1 are age-related and have little bearing on diseases and nutritures. DNA pol δ1 has great potential for a new biomarker of aging.

Carbonic anhydrases III and IV autoantibodies in rheumatoid arthritis, systemic lupus erythematosus, diabetes, hypertensive renal disease, and heart failure.

In the present study, the CA III and IV autoantibodies, CA activity, antioxidant enzymes and cytokines in rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), diabetes, hypertensive renal disease, and heart failure were investigated. The anti-CA III antibody titers in patients with RA, SLE, and type 1 diabetes (T1D) were significantly higher than that in control groups (P < 0.05). The anti-CA IV antibody titers in patients with RA, SLE, type 1 diabetic nephropathy (T1DN), and heart failure were significantly higher than that in control groups (P < 0.05) while anti-CA IV antibody could suppress the total CA activity. The SOD and GPx levels in patients with RA, SLE, and T1DN were significantly lower than that in control groups (P < 0.05). IL-6, IL-17, IFN-γ, and TNF-α levels were significantly higher in SLE group compared with the control group (P < 0.05). Weak but significant correlations were found between anti-CA III antibodies and ESR in RA (r = 0.403, P = 0.013) and SLE patients (r = 0.397, P = 0.007). These results suggested that the generation of CA III and IV autoantibodies, antioxidant enzymes, and cytokines might influence each other and CA autoantibodies might affect the normal physiology function of CA.

Amyloid-ß protein and MicroRNA-384 in NCAM-Labeled exosomes from peripheral blood are potential diagnostic markers for Alzheimer's disease.

OBJECTIVE: We aimed to establish a method to determine whether amyloid-ß (Aß) protein and miR-384 in peripheral blood neural cell adhesion molecule (NCAM)/ATP-binding cassette transporter A1 (ABCA1) dual-labeled exosomes may serve as diagnostic markers for the diagnosis of Alzheimer's disease (AD). METHODS: This was a multicenter study using a two-stage design. The subjects included 45 subjective cognitive decline (SCD) patients, 50 amnesic mild cognitive impairment (aMCI) patients, 40 AD patients, and 30 controls in the discovery stage. The results were validated in the verification stage in 47 SCD patients, 45 aMCI patients, 45 AD patients, and 30 controls. NCAM single-labeled and NCAM/ABCA1 double-labeled exosomes in the peripheral blood were captured and detected by immunoassay. RESULTS: The Aß42, Aß42/40 , Tau, P-T181-tau, and miR-384 levels in NCAM single-labeled and NCAM/ABCA1 double-labeled exosomes of the aMCI and AD groups were significantly higher than those of the SCD, control, and vascular dementia (VaD) groups (all p < 0.05). The Aß42 and miR-384 levels in NCAM/ABCA1 dual-labeled exosomes of the aMCI and AD groups were higher than those of the control and VaD groups (all p < 0.05). The exosomal Aß42, Aß42/40 , Tau, P-T181-tau, and miR-384 levels in peripheral blood were correlated with those in cerebrospinal fluid (all p < 0.05). CONCLUSION: This study, for the first time, established a method that sorts specific surface marker exosomes using a two-step immune capture technology. The plasma NCAM/ABCA1 dual-labeled exosomal Aß42/40 and miR-384 had potential advantages in the diagnosis of SCD.

ABCA1-Labeled Exosomes in Serum Contain Higher MicroRNA-193b Levels in Alzheimer's Disease.

OBJECTIVE: We aimed to establish a method to determine whether microRNA-193b (miR-193b) levels in ABCA1-labeled serum exosomes might serve as a marker for the diagnosis of Alzheimer's disease. METHODS: We used immunocapture methods to determine the levels of ABCA1-labeled exosomal miR-193b in cultures of white blood cells (WBCs), red blood cells (RBCs), mouse hippocampal neuron HT-22 cells, and primary mouse neuronal cells. ABCA1-labeled exosomal miR-193b levels were also evaluated in the cerebrospinal fluid (CSF) and serum of APP/PS1 double-transgenic mice, as well as control subjects (n = 60) and study participants with subjective cognitive decline (SCD, n = 89), stage and mild cognitive impairment (MCI, n = 92), and dementia of the Alzheimer type (DAT, n = 92). RESULTS: ABCA1 levels of exosomes harvested from the medium of HT-22 cells and neurons were significantly higher than those of RBCs and WBCs (P < 0.05). Exosomal ABCA1 from the CSF of APP/PS1 mice were transmitted to the serum of wild-type mice after injection, and high miR-193b levels were observed in both the serum and CSF after injection. The ABCA1-labeled exosomal miR-193b levels were higher in the CSF of MCI and DAT patients compared with the CSF of the control group (P < 0.05). The ABCA1-labeled exosomal miR-193b were also slightly higher (P > 0.05) in the serum of SCD patients and significantly higher in the serum of MCI and DAT patients compared with the serum of the control group (P < 0.05). CONCLUSION: This study provides a method to capture specific exosomes. Detection of serum exosomes labeled with ABCA1 may facilitate the early diagnosis of AD.

Preliminary study on the function of the POLD1 (CDC2) EXON2 c.56G>A mutation.

BACKGROUND: Fanconi anemia (FA) is a rare recessive disease characterized by DNA damage repair deficiency, and DNA polymerase δ (whose catalytic subunit is encoded by POLD1, also known as CDC2) is closely related to DNA damage repair. Our previous study identified a novel POLD1 missense mutation c.56G>A (p. Arg19>His) in FA family members. However, the function of the POLD1 missense mutation is currently unknown. This study aimed to uncover the biological function of the POLD1 missense mutation. METHODS: Stable cell lines overexpressing wild-type POLD1 or mutant POLD1 (c.56G>A, p.Arg19His) were constructed by lentivirus infection. Cell growth curve analysis, cell cycle analysis, and a comet assay were used to analyze the function of the POLD1 mutation. RESULTS: The growth and proliferative ability of the cells with POLD1 mutation was decreased significantly compared with those of the wild-type cells (Student's t test, p < .05). The percentage of cells in the G0/G1 phase increased, and the percentage of cells in the S phase decreased significantly when POLD1 was mutated (Student's t test, p < .05). Moreover, the Olive tail moment value of the cells with the POLD1 mutation was significantly higher than that of the cells with wild-type POLD1 after H2 O2 treatment. CONCLUSIONS: The POLD1 mutation inhibited cell proliferation, slowed cell cycle progression, and reduced DNA damage repair.

Genetic Diversity, Antimicrobial Resistance, and Virulence Genes of Aeromonas Isolates from Clinical Patients, Tap Water Systems, and Food.

OBJECTIVE: This study aimed to evaluate the genetic diversity, virulence, and antimicrobial resistance of Aeromonas isolates from clinical patients, tap water systems, and food. METHODS: Ninety Aeromonas isolates were obtained from Ma'anshan, Anhui province, China, and subjected to multi-locus sequence typing (MLST) with six housekeeping genes. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, while their resistance to 12 antibiotics was evaluated. Ten putative virulence factors and several resistance genes were identified by PCR and sequencing. RESULTS: The 90 Aeromonas isolates were divided into 84 sequence types, 80 of which were novel, indicating high genetic diversity. The Aeromonas isolates were classified into eight different species. PCR assays identified virulence genes in the isolates, with the enterotoxin and hemolysin genes act, aerA, alt, and ast found in 47 (52.2%), 13 (14.4%), 22 (24.4%), and 12 (13.3%) of the isolates, respectively. The majority of the isolates (≥ 90%) were susceptible to aztreonam, imipenem, cefepime, chloramphenicol, gentamicin, tetracycline, and ciprofloxacin. However, several resistance genes were detected in the isolates, as well as a new mcr-3 variant. CONCLUSIONS: Sequence type, virulence properties, and antibiotic resistance vary in Aeromonas isolates from clinical patients, tap water systems, and food.

The role of squamous cell carcinoma antigen (SCC Ag) in outcome prediction after concurrent chemoradiotherapy and treatment decisions for patients with cervical cancer.

At present, the standard treatment approach for locally advanced cervical cancer is concurrent chemoradiotherapy (CCRT). An elevated pretreatment squamous cell carcinoma antigen (SCC Ag) level is associated with extensive tumors and poor survival for patients with cervical cancer treated with definitive CCRT. SCC Ag levels can be used to help physicians make decisions regarding surgery, avoiding the complications of double treatment modalities. Elevated SCC Ag is associated with radiotherapy resistance, and the rate of SCC Ag reduction during CCRT can predict tumor response after treatment. Moreover, the failure of SCC Ag levels to normalize posttreatment can predict tumor relapse, with a specificity higher than 70%, and adjuvant therapies should be considered for these patients. SCC Ag also plays an important role in the early detection of tumor relapse in patients with cervical cancer during follow-up after CCRT, with high sensitivity and good cost-effectiveness.

Alcohol Dehydrogenase 1B Suppresses ß-Amyloid-Induced Neuron Apoptosis.

ß-amyloid (Aß) deposition, neurofibrillary tangles induced by phosphorylation of tau protein, and neuronal apoptosis are pathological hallmarks of Alzheimer's disease (AD). The dementia rate in alcoholic abusers were found to be higher than in control people. The present study explored the potential roles of alcohol dehydrogenase 1B (ADH1B) in AD pathology by determining the ADH1B levels in AD patient sera, in the hippocampus of APP/PS-1 AD model mice, and in an AD model cell line treated with Aß1-42. The results show that ADH1B levels decreased significantly both in the serum of AD patients and in the hippocampus of APP/PS-1 AD model mice. In addition, the apoptotic rate was reduced and viability was significantly increased in AD model cells transfected with ADH1B overexpression vector. The levels of the p75 neurotrophin receptor (p75NTR), an Aß1-42 receptor, were down-regulated in the ADH1B overexpressing AD model cell and up-regulated in cells transfected with the shRNA vector of ADH1B. Protein levels of cleaved caspase-3 and Bax decreased significantly, whereas Bcl-2 levels increased in cells overexpressing ADH1B. The opposite trend was observed for cleaved caspase-3, Bax, and Bcl-2 levels in cells transfected with the shRNA vector of ADH1B. The levels of reactive oxygen species (ROS) were found to be reduced in ADH1B overexpressing cells and increased when cells were transfected with the shRNA vector of ADH1B. These results indicate that ADH1B might be important in the prevention of AD, especially for abusers of alcohol, and a potential new target of AD treatment.

MiR-214-3p attenuates cognition defects via the inhibition of autophagy in SAMP8 mouse model of sporadic Alzheimer's disease.

The autophagy process is the major cellular degradation pathway for long-lived proteins and organelles. Dysfunction of autophagy may lead to several neurodegenerative disorders. However, the regulation and function of autophagy in sporadic Alzheimer's disease (SAD) remain unclear. In this study, we established SAMP8 mouse as a suitable SAD model and performed microarray profiling to identify miR-214-3p as a SAD associated microRNA that was downregulated in hippocampal neurons of SAMP8 mice upon the induction of autophagy. Furthermore, decreased miR-214-3p level was detected in cerebrospinal fluid from SAD patients. Overexpression of miR-214-3p in primary neurons from SAMP8 mice inhibited autophagy, demonstrated by decreased levels of LC3ßII and Beclin1, and reduced number of GFP-LC3-positive autophagosome vesicles, and led to increased viability and decreased caspase-mediated apoptosis. Conversely, antagomiR-214-3p promoted autophagy and apoptosis in neurons from SAMP8 mice. Mechanistically, miR-214-3p negatively regulated Atg12 expression by targeting the 3'-untranslated region of Atg12. Treatment of SAMP8 mice with miR-214-3p attenuated neuronal apoptosis and improved behavioral performance. Taken together, these results suggest that miR-214-3p suppresses autophagy and alleviates hippocampal neuron apoptosis, which indicates that miR-214-3p represents a new potential neuroprotective factor for SAD.

MiR-299-5p regulates apoptosis through autophagy in neurons and ameliorates cognitive capacity in APPswe/PS1dE9 mice.

Abnormalities of autophagy can result in neurodegenerative disorders such as Alzheimer's disease (AD). Nevertheless, the regulatory mechanisms of autophagy in AD are not well understood. Here, we describe our findings that microRNA (miR)-299-5p functions as an autophagy inhibitor by suppressing Atg5 and antagonizing caspase-dependent apoptosis. We observed decreased levels of miR-299-5p both in primary neurons under conditions of starvation and in hippocampi of APPswe/PS1dE9 mice. Additionally, low levels of miR-299-5p were observed in cerebrospinal fluid of AD patients. MiR-299-5p treatment resulted in attenuation of Atg5 and autophagy in primary neurons from APPswe/PS1dE9 mice, N2a cells and SH-SY5Y cells, whereas antagomiR-299-5p enhanced autophagy. Atg5 was verified as a direct target of miR-299-5p by dual luciferase reporter assays. Furthermore, transfection of miR-299-5p into primary hippocampal neurons caused the attenuation of caspase-mediated apoptosis, which was reversed upon starvation-induced autophagy. Inhibition of autophagy by shRNA knockdown of LC3ß reduced apoptotic neuron death induced by antagomiR-299-5p. Injection of agomiR-299-5p into the cerebral ventricles of AD mice inhibited both autophagy and apoptosis and also improved the cognitive performance of mice. Overall, our results suggest that miR-299-5p modulates neuron survival programs by regulating autophagy. Thus, miR-299-5p serves as a potential neuroprotective factor in AD.

MicroRNA-193b is a regulator of amyloid precursor protein in the blood and cerebrospinal fluid derived exosomal microRNA-193b is a biomarker of Alzheimer's disease.

Amyloid precursor protein (APP) has an important function in the generation of Alzheimer's disease (AD). In our previous study, miR­193b was found to be downregulated in the hippocampi of 9­month­old APP/PS1 double­transgenic mice using microRNA (miR) array. In the present study, bioinformatic analyses showed that miR­193b was a miR that was predicted to potentially target the 3'­untranslated region (UTR) of APP. Subsequently, the function of miR­193b on APP was studied. The levels of miR­193b, exosomal miR­193b, Aß, tau, p­tau, HCY and APOE in samples from APP/PS1 double­transgenic mice, mild cognitive impairment (MCI) and dementia of Alzheimer­type (DAT) patients, were measured. The results indicated that overexpression of miR­193b could repress the mRNA and protein expression of APP. The miR­193b inhibitor oligonucleotide induced upregulation of APP. Binding sites of miR­193b in the 3'­UTR of APP were identified by luciferase assay. MCI and DAT patients had lower exosomal miR­193b, but not total miR­193b, in the blood as compared with the controls. DAT patients had lower exosomal miR­193b levels in blood as compared with the MCI group. A decreased exosomal miR­193b expression level was additionally observed in the cerebral spinal fluid (CSF) of DAT patients. Negative correlations were found between exosomal miR­193b and Aß42 in the CSF of DAT patients. In conclusion, these findings showed that miR­193b may function in the development of AD and exosomal miR­193b has potential as a novel, non-invasive, blood­based biomarker of MCI and DAT patients.

MicroRNA-384 regulates both amyloid precursor protein and ß-secretase expression and is a potential biomarker for Alzheimer's disease.

Amyloid precursor protein (APP) and ß-site APP cleaving enzyme (BACE-1) play important roles in the pathogenesis of Alzheimer's disease (AD). In this study, using bioinformatics analysis, we demonstrate that miR-384 is a microRNA (miRNA or miR) predicted to potentially target the 3' untranslated regions (3'-UTRs) of both APP and BACE-1. SH-SY5Y cells were transfected with miR-384 mimic oligonucleotide, miR-384 inhibitor oligonucleotide, or a non-specific control siRNA. We found that the overexpression of miR-384 suppressed the mRNA and protein expression of both APP and BACE-1. The miR-384 inhibitor oligonucleotide induced the upregulation of APP and BACE-1. The activity of BACE-1 was altered following the change in its protein expression. The binding sites of miR-384 on the 3'-UTRs of APP and BACE-1 were identified by luciferase assay. Furthermore, cells were treasted with amyloid-ß (Aß)42. Aß42 downregulated miR-384 expression, leading to the continuous reduction in miR-384 expression. In addition, using a mouse model of AD, as well as patients with mild cognitive impairment (MCI) and dementia of Alzheimer's type (DAT), we examined the levels of miR-384 in cerebral spinal fluid (CSF) and serum. Patients with MCI and DAT had lower blood miR-384 levels compared with the controls. In addition, patients with DAT had lower blood miR-384 levels in blood compared with the MCI group. We also found decreased miR-384 expression in the several cerebral spinal fluid (CSF) of the patients with DAT. Negative correlations were observed between miR-384 and Aß42 in the serum and CSF from patients with AD. In conclusion, these findings demonstrate that miR-384 may plays a role in the development of AD and may be a potential non-invasive biomarker for the diagnosis of AD.

MicroRNA-135a and -200b, potential Biomarkers for Alzheimer׳s disease, regulate ß secretase and amyloid precursor protein.

Amyloid precursor protein (APP) and ß-site amyloid precursor protein cleaving enzyme (BACE-1) play important roles in the generation of Alzheimer׳s disease (AD), a progressive neurodegenerative disorder. In the present study, microRNA (miR) microarray was used to analyze the miR expression profiles in the hippocampi from APP/PS1 transgenic and wild type mice. The miRs with significant alteration and putative targets on APP or BACE-1 were retrieved (miR-135a, -200b and -429). The deregulations of these miRs were confirmed in mice and further verified in AD patient samples by qPCR. Primary mouse hippocampal neurons, SH-SY5Y and HEK293 cells were used to study the function of miRs on APP and BACE-1. We found that miR-135a, which was downregulated significantly in hippocampi from APP/PS1 transgenic mice compared with the wild type control, directly interacted with the 3'-UTR of BACE-1 and repressed its expression and activity. On the other hand, miR-200b and -429, which were downregulated significantly in hippocampi from APP/PS1 transgenic mice compared with the wild type control, targeted the 3'-UTR of APP and repressed its expression. Furthermore, Aß42 could downregulate miR-200b expression which may generate a vicious cycle resulted in accumulating Aß42. The levels of miR-135a and -200b in the serum of DAT group were significantly lower than that of control groups (P<0.05). The serum miR-200b level of MCI group was higher than that of DAT group (P<0.05) and lower than that of control group (P<0.05). We also found decreased miR-135a and -200b levels in the cerebrospinal fluid of DAT group compared with the control group (P<0.05). In conclusion, these findings showed that miR-135a, -200b and -429 may take part in the progress of AD; miR-200b was of great potential as noninvasive and easily detected blood-based biomarkers of MCI and DAT patients.

Effects of ovariectomy and 17beta-estradiol treatment on the renin-angiotensin system, blood pressure, and endothelial ultrastructure.

The purpose of this study was to determine whether the renin-angiotensin system (RAS), nitric oxide (NO), atrial natriuretic peptide (ANP), blood pressure (BP), ultrastructural characteristics, and endothelium-dependent relaxation of thoracic aorta were modulated by the estrogen level. Rats were divided into 3 groups: ovariectomized (OVX); not ovariectomized (sham); and ovariectomized and treated with subcutaneous 17beta-estradiol (15 microg/kg/day, OVX+E(2)) (n=15-17 per group). For 13 weeks after surgery, blood pressure, serum estrogen, NO, plasma angiotensin II (Ang II), ANP, and renin activity levels were monitored. Thirteen weeks after surgery, the vasodilator responses of the aortic rings to acetylcholine and the ultrastructural characteristics of the thoracic aorta were determined. In the 9th and 13th week, OVX rats had a significantly higher blood pressure than the other two groups (p<0.05). Ovariectomy led to a significant decrease in plasma Ang II level and a significant increase in renin activity in OVX rats compared to sham rats; this effect could be reversed by estrogen treatment. In the 5th, 9th, and 13th weeks, the serum NO level was significantly lower in the OVX group than in the sham group (p<0.05); this effect could be reversed by estrogen treatment. Plasma ANP levels in the 9th and 13th weeks were significantly lower in the OVX group (p<0.05), and plasma ANP levels could be completely restored by estrogen treatment. Ovariectomy markedly reduced endothelium-dependent relaxation in response to acetylcholine in isolated rat thoracic aortic rings; chronic estrogen treatment significantly restored endothelium-dependent relaxation in response to acetylcholine. Under electron microscopy, the endothelial cells in OVX rats were swollen, even necrosed; estrogen treatment inhibited these changes. These results strongly suggest that estradiol protects rats from the development of hypertension and has a protective effect on the endothelium by increasing NO and ANP levels while decreasing renin activity. However, there was a discordance between the effects that estradiol had on angiotensin II and on blood pressure. This might be the result of negative feedback that ultimately results in the overall suppression of the RAS.

17Beta-oestradiol regulates the expression of Na+/K+-ATPase beta1-subunit, sarcoplasmic reticulum Ca2+-ATPase and carbonic anhydrase iv in H9C2 cells.

1. It is necessary to improve our understanding of the effect of 17beta-oestradiol (E2) on the heart at a molecular and cellular level. In the present study, the effects of E2 on Na(+)/K(+)-ATPase, sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA) and carbonic anhydrase IV (CAIV) in H9C2 cells were investigated. To identify the mechanism of action of E2 on these proteins, the oestrogen receptor (ER) antagonist tamoxifen was used. 2. The results indicated that 1 and 100 nmol/L E2 can enhance the activity of Na(+)/K(+)-ATPase and SERCA and upregulate the expression of the Na(+)/K(+)-ATPase beta1-subunit, SERCA2a and CAIV at both the mRNA and protein level compared with 0 and 0.01 nmol/L E2. 17beta-Oestradiol had the greatest effect at 100 nmol/L; 1 micromol/L E2 did not further protein expression compared with 100 nmol/L E2. 3. Tamoxifen (10 nmol/L) significantly decreased the activity of SERCA, as well as the expression of the Na(+)/K(+)-ATPase beta1-subunit and SERCA at the mRNA and protein level, in H9C2 cells cultured with 1 nmol/L E2. Tamoxifen alone had no significant effect on these proteins in H9C2 cells. 4. It may be hypothesized that a suitable E2 concentration has a protective effect on the heart and that the actual dose of E2 used in hormone-replacement therapy is important in menopausal women.