Association between the Decrease in Medical Visit Frequency and Chronic Disease Worsening in the Early Stages of COVID-19 - A Longitudinal Study.

Objective This longitudinal study aimed to clarify the changes in the medical treatment behavior of Japanese patients with chronic diseases during the early phase of the coronavirus disease 2019 (COVID-19) pandemic and examine the factors associated with disease worsening. Methods Subjects with chronic diseases were selected from a panel survey that started at the beginning of the COVID-19 pandemic consists of 2,400 participants recruited via the Internet. Medical treatment behaviors (decrease in medical visit frequency, inability to take regular medications, and utilization of telephone/online medical care), psychological distress, and sociodemographic factors were evaluated at baseline (May 2020) and at the follow-up survey (February 2021). A worsening of chronic diseases was defined as those who answered "yes" to the question, "Has-the-condition-of-the-chronic-disease-worsened?". The factors related to the worsening of chronic diseases at follow-up were examined. Results A total of 514 participants (mean age 61.6±12.9 years) were analyzed. The percentage of participants who reported decreasing medical visit frequency was 34% at the baseline and 16.5% at follow-up, and those who reported a worsening of chronic diseases was 5.1% and 5.1%, respectively. A worsening of chronic diseases at follow-up was significantly associated with a younger age, a decreased frequency of medical visits, unemployment, a history of smoking, and psychological distress. Conclusions A decreased frequency of medical visits was observed among one-third of the participants with chronic disease in the early stage of the pandemic, and it reduced by half at follow-up. In the early stages of an emerging infectious disease pandemic, decreased regular hospital/clinic visits can lead to a worsening of chronic diseases. Those who had psychological distress, unemployment, and a history of smoking were vulnerable to a worsening chronic disease.

Current Diagnosis and Management of Primary Chylomicronemia.

Primary chylomicronemia (PCM) is a rare and intractable disease characterized by marked accumulation of chylomicrons in plasma. The levels of plasma triglycerides (TGs) typically range from 1,000 - 15,000 mg/dL or higher.PCM is caused by defects in the lipoprotein lipase (LPL) pathway due to genetic mutations, autoantibodies, or unidentified causes. The monogenic type is typically inherited as an autosomal recessive trait with loss-of-function mutations in LPL pathway genes (LPL, LMF1, GPIHBP1, APOC2, and APOA5). Secondary/environmental factors (diabetes, alcohol intake, pregnancy, etc.) often exacerbate hypertriglyceridemia (HTG). The signs, symptoms, and complications of chylomicronemia include eruptive xanthomas, lipemia retinalis, hepatosplenomegaly, and acute pancreatitis with onset as early as in infancy. Acute pancreatitis can be fatal and recurrent episodes of abdominal pain may lead to dietary fat intolerance and failure to thrive.The main goal of treatment is to prevent acute pancreatitis by reducing plasma TG levels to at least less than 500-1,000 mg/dL. However, current TG-lowering medications are generally ineffective for PCM. The only other treatment options are modulation of secondary/environmental factors. Most patients need strict dietary fat restriction, which is often difficult to maintain and likely affects their quality of life.Timely diagnosis is critical for the best prognosis with currently available management, but PCM is often misdiagnosed and undertreated. The aim of this review is firstly to summarize the pathogenesis, signs, symptoms, diagnosis, and management of PCM, and secondly to propose simple diagnostic criteria that can be readily translated into general clinical practice to improve the diagnostic rate of PCM. In fact, these criteria are currently used to define eligibility to receive social support from the Japanese government for PCM as a rare and intractable disease.Nevertheless, further research to unravel the molecular pathogenesis and develop effective therapeutic modalities is warranted. Nationwide registry research on PCM is currently ongoing in Japan with the aim of better understanding the disease burden as well as the unmet needs of this life-threatening disease with poor therapeutic options.

Homozygous Familial Hypercholesterolemia.

Familial hypercholesterolemia (FH) is an inherited disorder with retarded clearance of plasma LDL caused by mutations of the genes involved in the LDL receptor-mediated pathway and most of them exhibit autosomal dominant inheritance. Homozygotes of FH (HoFH) may have plasma LDL-C levels, which are at least twice as high as those of heterozygous FH (HeFH) and therefore four times higher than normal levels. Prevalence of HoFH had been estimated as 1 in 1,000,000 before but more recent genetic analysis surveys predict 1 in 170,000 to 300,000. Since LDL receptor activity is severely impaired, HoFH patients do not or very poorly respond to medications to enhance activity, such as statins, and have a poorer prognosis compared to HeFH. HoFH should therefore be clinically distinguished from HeFH. Thorough family studies and genetic analysis are recommended for their accurate diagnosis.Fatal cardiovascular complications could develop even in the first decade of life for HoFH, so aggressive lipid-lowering therapy should be initiated as early as possible. Direct removal of plasma LDL by lipoprotein apheresis has been the principal measure for these patients. However, this treatment alone may not achieve stable LDL-C target levels and combination with drugs should be considered. The lipid-lowering effects of statins and PCSK9 inhibitors substantially vary depending on the remaining LDL receptor activity of individual patients. On the other hand, the action an MTP inhibitor is independent of LDL receptor activity, and it is effective in most HoFH cases.This review summarizes the key clinical issues of HoFH as well as insurance coverage available under the Japanese public healthcare system.

[Estrogen, SERM].

Osteoporosis is uncommon before menopause and dramatically increases in prevalence thereafter. That is why estrogens provide protection against osteoporosis. Studies of women receiving estrogen replacement have demonstrated improvements in bone mineral density (BMD) as well as endothelial function. Recent randomized trials, however, have produced equivocal results and raised questions about whether combined hormonal replacement therapy (HRT) prevents later cardiovascular events. Investigations of alternatives to HRT have suggested that selective estrogen receptor modulators (SERMs) may confer cardiovascular and osteoporosis protection. Raloxifene is a second-generation SERM used for the prevention and treatment of postmenopausal osteoporosis. Raloxifene decreases the incidence of vertebral fractures by 30-50% in postmenopausal women with osteoporosis. We also studied its effect on postmenopausal elderly women with osteoporosis.

The effects of selective estrogen receptor modulator treatment following hormone replacement therapy on elderly postmenopausal women with osteoporosis.

OBJECTIVES: A comparison between the atheroprotective and osteoprotective effects of the selective estrogen receptor modulator (SERM) raloxifene and those of hormone replacement therapy (HRT) has not been made in elderly women. METHODS: A randomized prospective controlled trial was performed in a cohort of 32 elderly Japanese women with osteoporosis receiving HRT (estriol plus medroxyprogesterone) for more than 1 year. In 16 randomly selected subjects, HRT was changed to raloxifene therapy (60mg/day, 71.4±3.4 years, SERM group). The other 16 patients were continued on HRT (71.8±2.9 years, HRT group). As a control group, 14 subjects were enrolled, did not take any medications and were age-matched to experimental patients (72.5±3.3 years, control group). Plasma lipids, TNFα, adiponectin, NO metabolites (NOx:NO2(-) and NO3(-)), cyclicGMP and bone-mineral density (BMD) were evaluated at baseline and at 26 and 52 weeks after enrollment. RESULTS: SERM (Raloxifene) increased high-density-lipoprotein cholesterol levels and tended to decrease low-density-lipoprotein cholesterol levels (P=0.058) compared with baseline. Adiponectin, NOx and cGMP levels were significantly increased after 6 months compared with baseline or the HRT group. TNFα was decreased by raloxifene. In control subjects, no significant changes were observed in any of these markers. Bone-mineral density was higher at baseline in the raloxifene and HRT groups than in the control group, and BMD increased 12 months after baseline in the HRT and control group. CONCLUSION: SERM improved BMD and endothelial function in elderly postmenopausal women with osteoporosis who had received HRT, and these effects were comparable to or slightly stronger than those of HRT. Changes in adiponectin and TNFα may underlie the improvements in endothelial function, such as NO signaling.

Place of death for the elderly in need of end-of-life home care: a study in Japan.

To investigate factors affecting the place of death of patients receiving home care services, we performed a retrospective cohort study using 252 elderly Japanese patients. During a 3-year period, 40 patients died at home (78.4 ± 12 years olds), and 59 patients died at hospitals (77.6 ± 13.4 years olds). Patient profiles, including their demographic characteristics, comorbidities, as well as formal and informal care levels were evaluated. Patients who died at home received a shorter term of home care, suffered malignancies more often and received visiting nurse services more often than those at hospitals. Age, gender, comorbidities, laboratory data, independency of activity of daily living (ADL), number of family looking after patients, number and dose of prescriptions and number of medical treatments such as decubitus were not different between these groups. Multivariate logistic regression analyses revealed that patients who died at home had an increased likelihood of suffering from malignancy (odds ratio = OR = 2.18, HR: 1.04-3.98, p = 0.049) and an increased likelihood of receiving visiting nurse services (OR = 3.13, HR: 1.08-6.21, p = 0.029) compared to those who died at hospitals. Thus, dying at home may be associated with cases of malignancy compared to other diseases in Japan, and it may be associated with a greater need for home visiting nurses. In conclusion, the nature of the patient's disease and the presence of visiting nurses influenced the decision regarding the patient's place of death. More study is necessary to better understand the end stages of death at home.

Endothelial progenitor cells as therapeutic agents in the microcirculation: an update.

This review evaluates novel beneficial effects of circulating endothelial progenitor cells (EPCs) as shown by several preclinical studies and clinical trials carried out to test the safety and feasibility of using EPCs. There are 31 registered clinical trials (and many others still ongoing) and 19 published studies. EPCs originate in the bone marrow and migrate into the bloodstream where they undergo a differentiation program leading to major changes in their antigenic characteristics. EPCs lose typical progenitor markers and acquire endothelial markers, and two important receptors, (VEGFR and CXCR-4), which recruit circulating EPCs to damaged or ischemic microcirculatory (homing to damaged tissues) beds. Overall, therapeutic angiogenesis will likely change the face of regenerative medicine in the next decade with many patients worldwide predicted to benefit from these treatments.

CXCR4/YY1 inhibition impairs VEGF network and angiogenesis during malignancy.

Tumor growth requires neoangiogenesis. VEGF is the most potent proangiogenic factor. Dysregulation of hypoxia-inducible factor (HIF) or cytokine stimuli such as those involving the chemokine receptor 4/stromal-derived cell factor 1 (CXCR4/SDF-1) axis are the major cause of ectopic overexpression of VEGF in tumors. Although the CXCR4/SDF-1 pathway is well characterized, the transcription factors executing the effector function of this signaling are poorly understood. The multifunctional Yin Yang 1 (YY1) protein is highly expressed in different types of cancers and may regulate some cancer-related genes. The network involving CXCR4/YY1 and neoangiogenesis could play a major role in cancer progression. In this study we have shown that YY1 forms an active complex with HIF-1alpha at VEGF gene promoters and increases VEGF transcription and expression observed by RT-PCR, ELISA, and Western blot using two different antibodies against VEGFB. Long-term treatment with T22 peptide (a CXCR4/SDF-1 inhibitor) and YY1 silencing can reduce in vivo systemic neoangiogenesis (P < 0.01 and P < 0.05 vs. control, respectively) during metastasis. Moreover, using an in vitro angiogenesis assay, we observed that YY1 silencing led to a 60% reduction in branches (P < 0.01) and tube length (P < 0.02) and a 75% reduction in tube area (P < 0.001) compared with control cells. A similar reduction was observed using T22 peptide. We demonstrated that T22 peptide determines YY1 cytoplasmic accumulation by reducing its phosphorylation via down-regulation of AKT, identifying a crosstalk mechanism involving CXCR4/YY1. Thus, YY1 may represent a crucial molecular target for antiangiogenic therapy during cancer progression.

Beneficial effect of the oligomerized polyphenol oligonol on high glucose-induced changes in eNOS phosphorylation and dephosphorylation in endothelial cells.

BACKGROUND AND PURPOSE: Hyperglycaemia is known to reduce nitric oxide (NO) bioavailability by modulating endothelial NO synthase (eNOS) activity, and polyphenols are believed to have cardiovascular benefit. One possible mechanism could be through interaction with eNOS. EXPERIMENTAL APPROACH: The effects of the oligomerized polyphenol oligonol on eNOS phosphorylation status and activity were examined in porcine aortic endothelial cells cultured in high glucose concentrations. KEY RESULTS: Exposure to high glucose concentrations strongly inhibited eNOS phosphorylation at Ser-1177 and dephosphorylation at Thr-495 in bradykinin (BK)-stimulated cells. These inhibitory effects of high glucose were significantly prevented by treatment with oligonol. Akt and p38 mitogen-activated protein kinase (MAPK) were activated in BK-stimulated cells. High glucose inhibited Akt activation but enhanced p38 MAPK activation, both of which were reversed by oligonol treatment. The phosphatidylinositol 3-kinase inhibitor wortmannin blocked the reversal by oligonol of phosphorylation at Ser-1177, but not dephosphorylation at Thr-495, in BK-stimulated cells exposed to high glucose. The effect of oligonol on BK dephosphorylation under high glucose was mimicked by protein kinase C (PKC) epsilon-neutralizing peptides. These data suggest that the effects of oligonol on high glucose-induced attenuation of eNOS Ser-1177 phosphorylation and Thr-495 dephosphorylation may be regulated by Akt activation and PKCepsilon inhibition respectively. Oligonol also prevented high glucose-induced attenuation of BK-stimulated NO production. CONCLUSIONS AND IMPLICATIONS: Oligonol prevented the impairment of eNOS activity induced by high glucose through reversing altered eNOS phosphorylation status. This mechanism may underlie the beneficial cardiovascular health effects of this oligomerized polyphenol.

Possibility of the regression of atherosclerosis through the prevention of endothelial senescence by the regulation of nitric oxide and free radical scavengers.

In the elderly, atherosclerotic diseases such as stroke and myocardial infarction occupy a major part of their causes of death and care. The elderly always have atherosclerosis in their aorta and other arteries and are exposed to risk of attacks. It is the elderly who should receive its safe, harmless and advanced treatment. Advanced stage of atherosclerosis in the elderly is progressed by complicated risk factors such as dyslipidemia and diabetes mellitus and specific risk factors for the elderly, aging (and menopause). Treatment of atherosclerotic disease may need special ones targeted for the elderly. Recent studies reported that frequencies of dyslipidemia were not decreased in the older oldest. In the elderly, impaired glucose tolerance occurs and it progresses atherosclerosis. Endothelial dysfunction like impairment of nitric oxide (NO) bioavailability also progresses atherosclerosis. Although we tried to regress the high cholesterol diet-induced atherosclerosis in rabbit aorta with a normal diet with or without statin, regression could not be achieved. NO targeting gene therapy (adenovirus endothelial nitric oxide synthase [eNOS] gene vector) regressed 20% of atherosclerotic lesions through reduction of lipid contents, however, a more integrated strategy is important for complete regression. We paid attention to NO bioavailability and developed two ways of increasing it in atherosclerosis: citrulline therapy and arginase II inhibition by estrogen. Further, we found a close relation between atherosclerosis and endothelial senescence and that NO can prevent it, especially in a diabetic model. Taken together, regression of atherosclerosis can be achieved by not only regulation of various risk factors but regulation of the cross-talk of NO and free radicals.

Clinical factors such as B-type natriuretic peptide link to factor VII, endothelial NO synthase and estrogen receptor alpha polymorphism in elderly women.

AIMS: This study evaluated the presence of genetic mutations in relation to thrombosis or atherosclerosis in elderly women. MAIN METHODS: This is an observational study of 93 Japanese women with a mean age of 80.9 years recruited from outpatient clinics of Nagoya University and its related hospitals. Ten single nucleotide polymorphisms (SNPs) were studied. Each gene studied acts in or is related to either blood coagulation (factor V Leiden, prothrombin G20210A, factor XIII Val34Leu, factor VII Arg353Gln, MTHFR C677T, beta-fibrinogen G-455A, PAI-1 4G/5G), metabolic syndrome-related pathways (PPARalpha Leu162Val), or endothelium/estrogen system (eNOS Glu298Asp, ERalpha IVS1-401). SNPs were analyzed for their relation to clinical values including lipids, B-type natriuretic peptide (BNP), fasting plasma glucose, tumor necrosis factor-alpha, interleukin-6, cyclic GMP, and nitric oxide metabolites. KEY FINDINGS: Comparisons between the distributions of different genotypes and clinical values showed three relationships. First, factor VII Arg353Gln and HDL-cholesterol (HDL-C) were linked to Arg/Arg carriers at higher levels (P=.049). The HDL-C to LDL-cholesterol ratio supported this link (P=.027). Second, eNOS Glu298Asp and triglycerides were linked to Glu/Glu carriers at higher levels (P=.031). Third, ERalpha IVS1-401 and BNP were related to CC genotype at lower levels (P=.031). Additionally, the last two relations showed that genotype does not influence the demarcation line of biomarkers, but the plasma/serum levels of biomarkers instead. SIGNIFICANCE: Correlations of factor VII Arg353Gln with HDL-C and eNOS Glu298Asp with triglycerides are new findings. Polymorphisms in the endothelium/estrogen system and the heart failure marker BNP are also correlated, with ERalpha IVS1-401 being the first identified marker. SNPs may be helpful for understanding the pathophysiology of atherosclerotic diseases in elderly women.

Nitric oxide and endothelial cellular senescence.

Cellular senescence is characterized by permanent exit from the cell cycle and the appearance of distinct morphological and functional changes associated with an impairment of cellular homeostasis. Many studies support the occurrence of vascular endothelial cell senescence in vivo, and the senescent phenotype of endothelial cells can be transformed from anti-atherosclerotic to pro-atherosclerotic. Thus, endothelial cell senescence promotes endothelial dysfunction and may contribute to the pathogenesis of age-associated vascular disorders. Emerging evidence suggests that increasing nitric oxide (NO) bioavailability or endothelial NO synthase (eNOS) activity activates telomerase and delays endothelial cell senescence. In this review, we discuss the potential mechanisms underlying the ability of NO to prevent endothelial cell senescence and describe the possible changes in the NO-mediated anti-senescence effect under pathophysiological conditions, including oxidative stress and hyperglycemia. Further understanding of the mechanisms underlying the anti-senescence effect of NO in endothelial cells will provide insights into the potential of eNOS-based anti-senescence therapy for age-associated vascular disorders.

[Hormone replacement Up-to-date. The effect of estrogen on vascular function and atherosclerosis].

Not only life span but also life expectancy in all ages are longer in female than male. The incidence of ischemic coronary diseases are drastically increased after menopause and reached almost same severity with that of male after 75 years old. An abundance of epidemiological data confirms this atheroprotective effect of estradiol. The antiatherosclerotic effects of estradiol were thought to be partly attributable to changes in plasma lipid levels (ie, the increase in HDL cholesterol and decrease in LDL cholesterol). However, the contribution of these changes to the total antiatherosclerotic effect of estrogen is only 50%, based on multiple regression analyses. Recently, estrogen receptors have been found in the vascular endothelium and smooth muscle cells, as well as in blood cells such as monocytes. Interest has focused on the role of nitric oxide (NO), because NO has antiatherosclerotic effects. Direct evidence was shown that NO mediates the antiatherosclerotic effect of estrogen. We have found that estrogen acts via an NO-mediated system in vivo and in vitro. However, adverse effects such as thrombosis were reported in estrogen/progesterone replacement therapy in mega clinical trials such as WHI study. We would like to explain and discuss these biphasic effects of estrogen on atherosclerotic diseases including their risk factors such as hyperlipidemia, diabetes mellitus and hypertension.

Nitric oxide metabolites are associated with survival in older patients.

OBJECTIVES: To assess the efficacy of various vascular endocrinological substances, such as plasma nitric oxide metabolites (NOx), as surrogate markers of survival in older patients. DESIGN: Prospective cohort, observational. SETTING: Nagoya University Hospital and related hospitals, Japan. PARTICIPANTS: One hundred fifty patients aged 70 and older, recruited consecutively from the outpatient clinics of Nagoya University Hospital and related hospitals. MEASUREMENT: Serum biochemical analyses such as albumin and total cholesterol, various prognostic markers, such as tumor necrosis factor (TNF)-alpha, NOx, activities of daily living (ADLs), and instrumental ADLs (IADLs) were evaluated on enrollment. ADLs, IADLs, and comorbidities, especially depression and impaired cognition, were evaluated on enrollment. The main outcome was survival rate over 2.75 years. RESULTS: Forty-nine patients died during the follow-up period. Mann-Whitney U-test showed that hemoglobin, total protein, serum albumin, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, high sensitive c-reactive protein, NOx, B-type natriuretic peptide, interleukin-6, and TNF-alpha levels; ADLs; cognitive impairment; and depressive status were significantly different for subjects who survived and those who died. Of the dependent variables in the Cox proportional hazards regression analyses, only ADLs, NOx, and albumin were significantly different. In the Kaplan-Meier analyses of mortality, the prognosis of patients in the third and fourth quartiles of NOx was significantly worse than that of patients in the first or second quartile. The prognosis of patients with impaired ADLs was worse than that of other patients for the overall period. CONCLUSION: Lower levels of NOx may be associated with survival in older patients. It may be an effective marker, like ADLs, which is a well-known marker.

Risks of CHD identified by different criteria of metabolic syndrome and related changes of adipocytokines in elderly postmenopausal women.

The objective of this study was to assess the capacity of different criteria of metabolic syndrome (MetS) to identify risks of coronary heart diseases (CHDs) and related changes of adipocytokines in postmenopausal women. A cross-sectional study was carried out in 225 community-dwelling, elderly postmenopausal Chinese women (age, 66.77+/-5.09 years) without hormone replacement therapy (HRT). Baseline data such as blood pressure, body mass index (BMI), serum lipid profiles, and fasting glucose were analyzed, and insulin sensitivity was estimated via the homeostasis model assessment for insulin resistance. Serum tumor necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), and adiponectin were measured simultaneously. The prevalence of MetS identified by the Third Report of the National Cholesterol Education Programme Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults, the International Diabetes Federation (IDF), the Chinese Diabetes Society (CDS), and the Japanese Society of Internal Medicine (JPN) were 27.31%, 37.34%, 23.29%, and 13.65%, respectively. No significant differences of baseline data were found among different MetS groups, except for a significant higher waist circumference in the JPN-MetS group as compared with other MetS groups. The prevalence of confirmed CHD in the four MetS groups were 26.2%, 18.6%, 26.9%, and 32%, respectively. Odds ratios for CHD were 1.905 (95% CI=1.273-2.851), 1.208 (95% CI=0.778-1.876), 1.997 (95% CI=1.238-3.221), and 2.336 (95% CI=1.119-4.876), respectively. The JPN-MetS group had higher levels of TNFalpha and IL-6, whereas the CDS-MetS group correlated better with lower adiponectin levels. The IDF definition for MetS is the most sensitive one with regard to metabolic disorders, whereas JPN and CDS definitions correlate better with CHD and changes of adipocytokines among the four criteria studied.

High glucose downregulates the number of caveolae in monocytes through oxidative stress from NADPH oxidase: implications for atherosclerosis.

Atherosclerosis, an inflammatory disease, is closely associated with hyperglycemia, major sign of diabetes mellitus. Caveolae are vesicular invaginations of the plasma membrane that mediate the intracellular transport of lipids such as cholesterol. We evaluated the relationship between the expression of caveolin-1 and the number of caveolae in macrophages under conditions of high glucose concentration. Increased superoxide production, induction of inducible nitric oxide synthase (iNOS), and decreased caveolin-1 were observed in a concentration-dependent manner in THP-1 derived macrophages with high glucose concentrations. Mannitol, used as an osmotic control, showed no effects. Furthermore, co-localization of the NADPH oxidase component, p47(phox), and caveolin was confirmed by confocal microscopy. An atomic force microscopy (AFM) study showed that high glucose concentrations reduced the number and size of the caveolae. The percentage of cells with fragmented DNA was increased in cells grown in hyperglycemic media. Taken together, high glucose concentrations suppress the levels of caveolin-1 expression and reduce the number of caveolae. This might be due to the actions of superoxide via the activation of NADPH oxidase by translocation of its component and uncoupling of induced iNOS in macrophages. Furthermore, the apoptosis of macrophages might occur with high glucose concentrations, leading to the spreading of lipids from macrophages into intracellular spaces in the vessel wall.

beta1 antagonist and beta2 agonist, celiprolol, restores the impaired endothelial dependent and independent responses and decreased TNFalpha in rat with type II diabetes.

UNLABELLED: The effect of beta antagonists in the diabetic vascular lesion is controversial. We investigated the effect of celiprolol hydrochloride, a beta1 antagonist and mild beta2 agonist, on the lesions and function in type II male Otsuka Long-Evans Tokushima Fatty (OLETF) diabetic rats. OLETF rats were fed regular chow with or without atenolol (25 mg/kg/day) or celiprolol (100 mg/kg/day) treatment (group DM, no treatment; group DM-a, atenolol treatment; group DM-c, celiprolol treatment), and treatment was continued for 31 days. Separately, normoglycemic control rats, LETO, were prepared as group C. On day 3, endothelial cells of the right internal carotid artery were removed by balloon injury, and the rats were evaluated 4 weeks after balloon injury. The plasma glucose and lipid levels were unchanged throughout the treatment period. Intimal thickening was observed in the right carotid artery in the DM and DM-a groups; however, little thickening was observed in those of DM-c rats. Acetylcholine-induced NO-dependent relaxation in arteries was improved in DM-c rats compared with DM and DM-a rats (maximum relaxation DM 30.8+/-4.5, DM-a 37.4+/-3.9, DM-c 48.8+/-4.6%, *P<0.05 vs. DM for DM-c rats). Tone-related basal NO release and acetylcholine-induced NO-dependent relaxation in the arteries and plasma NO(x) (sum of NO(2)(-) and NO(3)(-)) were greater in DM-c and C groups than in DM and DM-a groups. The serum TNFalpha levels did not increase in DM-c rats compared with those of the DM or DM-a groups, and were comparable with those of group C. CONCLUSION: In conclusion, Celiprolol improves endothelial function in the arteries of OLETF rats, and further restore it 4 weeks after endothelial denudation in the arteries of OLETF rats. NO and O(2)(-) may have a role in the important underlying mechanisms by reducing the TNFalpha levels.

17beta-estradiol antagonizes the down-regulation of endothelial nitric-oxide synthase and GTP cyclohydrolase I by high glucose: relevance to postmenopausal diabetic cardiovascular disease.

In postmenopausal women, the risk of diabetic cardiovascular disease drastically increases compared with that of men or premenopausal women. However, the mechanism of this phenomenon has not yet been clarified. We hypothesized that the beneficial effects of estrogen on endothelial function may be relevant to protection against hyperglycemia-induced vascular derangement. Bovine aortic endothelial cells were incubated for 72 h in the presence and absence of the physiological concentration of 17beta-estradiol (17beta-E2) under normal and high-glucose conditions. The presence of 17beta-E2 significantly counteracted the reduction in basal nitric oxide production under high-glucose conditions. This finding was associated with the recovery of endothelial nitric-oxide synthase (eNOS) protein expression, tetrahydrobiopterin (BH4) levels, and the activity and gene expression of GTP cyclohydrolase I (GTPCH-I), a rate-limiting enzyme for BH4 synthesis. Both the gene transfer of estrogen receptor alpha using adenovirus and treatment with the protein kinase C inhibitor bisindolylmaleimide I significantly enhanced the effects of 17beta-E2 treatment under high-glucose conditions, whereas these effects were abolished by the estrogen receptor antagonist ICI 182,780 (faslodex). Transfection of small-interfering RNA targeting eNOS resulted in a marked reduction in GTPCH-I mRNA under both normal and high-glucose conditions, but this reduction was strongly reversed by 17beta-E2. These results suggest that the activation of ERalpha with 17beta-E2 can counteract high-glucose-induced down-regulation of eNOS and GTPCH-I in endothelial cells. Therefore, estrogen deficiency may result in an exaggeration of hyperglycemia-induced endothelial dysfunction, leading to the development of cardiovascular disease in postmenopausal diabetic women.