Effectiveness of negative pressure wound therapy for the wound of ileostomy closure: a multicenter, phase II randomized controlled trial.

BACKGROUND: The American Society of Surgery and American Society for Surgical Infections issued guidelines for surgical site infections (SSIs) in December 2016. These guidelines recommend a purse-string suture (PSS) for stoma closure as it facilitates granulation and enables open wound drainage. This study investigated the effect of using negative pressure wound therapy (NPWT) along with standard PSS and aimed to determine the optimal period of NPWT use. METHODS: The patients were divided into three groups as follows: Group A, postoperative wound management alone with gauze exchange as the representative of conventional PSS; Group B, the performed management was similar to that of Group A plus NPWT for 1 week; and Group C, the performed management was similar to that of Group A plus NPWT for 2 weeks. Regarding objective measures, the wound reduction rate was the primary outcome, and the incidence of SSIs, length of hospital stay, and wound healing duration were the secondary outcomes. RESULTS: In total, 30 patients (male: 18, female: 12) were enrolled. The average age was 63 (range: 43-84) years. The wound reduction rate was significantly higher in Group B than in Group A on postoperative days (PODs) 7 (66.1 vs. 48.4%, p = 0.049) and 10 (78.6 vs. 58.2%, p = 0.011), whereas no significant difference was observed on POD 14. Compared with Group A, Group C (POD 7: 65.9%, POD 10: 69.2%) showed an increase in the wound reduction rate on POD 7, although the difference was not significant (p = 0.075). SSIs were observed in Groups B (n = 2) and C (n = 2) (20%) but not in Group A (0%). CONCLUSIONS: The most effective duration of NPWT use for ileostomy closure with PSS in terms of the maximum wound reduction rate was from PODs 3 to 10. However, NPWT did not shorten the wound healing duration. NPWT may reduce the wound size but should be used with precautions for SSIs. The small sample size (30 cases), the use of only one type of NPWT system, and the fact that wound assessment was subjective and not blinded were the limitations of this study. Further studies are needed to confirm our findings. TRIAL REGISTRATION: UMIN Clinical Trials Registry; UMIN000032174 (10/04/2018).

Androgen receptor promotes sex-independent angiogenesis in response to ischemia and is required for activation of vascular endothelial growth factor receptor signaling.

BACKGROUND: Hypoandrogenemia is associated with an increased risk of ischemic diseases. Because actions of androgens are exerted through androgen receptor (AR) activation, we studied hind-limb ischemia in AR knockout mice to elucidate the role of AR in response to ischemia. METHODS AND RESULTS: Both male and female AR knockout mice exhibited impaired blood flow recovery, more cellular apoptosis, and a higher incidence of autoamputation after ischemia. In ex vivo and in vivo angiogenesis studies, AR-deficient vascular endothelial cells showed reduced angiogenic capability. In ischemic limbs of AR knockout mice, reductions in the phosphorylation of the Akt protein kinase and endothelial nitric oxide synthase were observed despite a robust increase in hypoxia-inducible factor 1α and vascular endothelial cell growth factor (VEGF) gene expression. In in vitro studies, siRNA-mediated ablation of AR in vascular endothelial cells blunted VEGF-stimulated phosphorylation of Akt and endothelial nitric oxide synthase. Immunoprecipitation experiments documented an association between AR and kinase insert domain protein receptor that promoted the recruitment of downstream signaling components. CONCLUSIONS: These results document a physiological role of AR in sex-independent angiogenic potency and provide evidence of novel cross-talk between the androgen/AR signaling and VEGF/kinase insert domain protein receptor signaling pathways.

Pitavastatin, an HMG-CoA reductase inhibitor, exerts eNOS-independent protective actions against angiotensin II induced cardiovascular remodeling and renal insufficiency.

Angiotensin II (Ang II) plays a pivotal role in cardiovascular remodeling leading to hypertension, myocardial infarction, and stroke. Pitavastatin, an HMG-CoA reductase inihibitor, is known to have pleiotropic actions against the development of cardiovascular remodeling. The objectives of this study were to clarify the beneficial effects as well as the mechanism of action of pitavastatin against Ang II-induced organ damage. C57BL6/J mice at 10 weeks of age were infused with Ang II for 2 weeks and were simultaneously administered pitavastatin or a vehicle. Pitavastatin treatment improved Ang II-induced left ventricular hypertrophy and diastolic dysfunction and attenuated enhancement of cardiac fibrosis, cardiomyocyte hypertrophy, coronary perivascular fibrosis, and medial thickening. Ang II-induced oxidative stress, cardiac TGFbeta-1 expression, and Smad 2/3 phosphorylation were all attenuated by pitavastatin treatment. Pitavastatin also reduced Ang II-induced cardiac remodeling and diastolic dysfunction in eNOS-/- mice as in wild-type mice. In eNOS-/- mice, the Ang II-induced cardiac oxidative stress and TGF-beta-Smad 2/3 signaling pathway were enhanced, and pitavastatin treatment attenuated the enhanced oxidative stress and the signaling pathway. Moreover, pitavastatin treatment reduced the high mortality rate and improved renal insufficiency in Ang II-treated eNOS-/- mice, with suppression of glomerular oxidative stress and TGF-beta-Smad 2/3 signaling pathway. In conclusion, pitavastatin exerts eNOS-independent protective actions against Ang II-induced cardiovascular remodeling and renal insufficiency through inhibition of the TGF-beta-Smad 2/3 signaling pathway by suppression of oxidative stress.

Endothelial Nitric Oxide Synthase-Independent Pleiotropic Effects of Pitavastatin Against Atherogenesis and Limb Ischemia in Mice.

AIM: Statins have a protective impact against cardiovascular diseases through not only lipid-lowering effects but also pleiotropic effects, including activation of the endothelial nitric oxide synthase (eNOS) system. We aimed to clarify the protective effects of a statin against atherogenesis and ischemia in eNOS－/－ mice. METHODS: Study 1. eNOS－/－ Apolipoprotein E (ApoE)－/－ mice were treated with a vehicle or pitavastatin (0.3 mg/kg/day) for 4 weeks. Study 2. eNOS－/－ mice were also treated with a vehicle or the same dose of pitavastatin for 2 weeks prior to hind-limb ischemia. RESULTS: In Study 1, pitavastatin attenuated plaque formation and medial fibrosis of the aortic root with decreased macrophage infiltration in eNOS－/－ ApoE－/－ mice. PCR array analysis showed reductions in aortic gene expression of proatherogenic factors, including Ccl2 and Ccr2 in pitavastatin-treated double mutant mice. In addition, pitavastatin activated not only atherogenic p38MAPK and JNK but also anti-atherogenic ERK1/2 and ERK5 in the aorta of the double mutant mice. In Study 2, pitavastatin prolonged hind-limb survival after the surgery with increased BCL2-to-BAX protein ratio and inactivated JNK. Enhanced expression of anti-apoptotic genes, including Vegf, Api5, Atf5, Prdx2, and Dad1, was observed in the ischemic limb of pitavastatin-treated eNOS－/－ mice. Furthermore, pitavastatin activated both aortic and skeletal muscle AMPK in the eNOS-deficient vascular injury models. CONCLUSION: Pitavastatin exerts eNOS-independent protective effects against atherogenesis and hind-limb ischemia in mice, which may occur via modifications on key molecules such as AMPK and diverse molecules.

The Role of Heparin Cofactor â ¡ in the Regulation of Insulin Sensitivity and Maintenance of Glucose Homeostasis in Humans and Mice.

AIM: Accelerated thrombin action is associated with insulin resistance. It is known that upon activation by binding to dermatan sulfate proteoglycans, heparin cofactor Ⅱ(HCⅡ) inactivates thrombin in tissues. Because HCⅡ may be involved in glucose metabolism, we investigated the relationship between plasma HCⅡ activity and insulin resistance. METHODS AND RESULTS: In a clinical study, statistical analysis was performed to examine the relationships between plasma HCⅡ activity, glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG), and homeostasis model assessment-insulin resistance (HOMA-IR) in elderly Japanese individuals with lifestyle-related diseases. Multiple regression analysis showed significant inverse relationships between plasma HCⅡ activity and HbA1c (p=0.014), FPG (p=0.007), and HOMA-IR (p= 0.041) in elderly Japanese subjects. In an animal study, HCⅡ＋/＋ mice and HCⅡ＋/- mice were fed with a normal diet or high-fat diet (HFD) until 25 weeks of age. HFD-fed HCⅡ＋/- mice exhibited larger adipocyte size, higher FPG level, hyperinsulinemia, compared to HFD-fed HCⅡ＋/＋ mice. In addition, HFD-fed HCⅡ＋/- mice exhibited augmented expression of monocyte chemoattractant protein-1 and tumor necrosis factor, and impaired phosphorylation of the serine/threonine kinase Akt and AMP-activated protein kinase in adipose tissue compared to HFD-fed HCⅡ＋/＋ mice. The expression of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase was also enhanced in the hepatic tissues of HFD-fed HCⅡ＋/- mice. CONCLUSIONS: The present studies provide evidence to support the idea that HCⅡ plays an important role in the maintenance of glucose homeostasis by regulating insulin sensitivity in both humans and mice. Stimulators of HCⅡ production may serve as novel therapeutic tools for the treatment of type 2 diabetes.

High plasma aldosterone concentration is a novel risk factor of cognitive impairment in patients with hypertension.

Cognitive impairment leading to dementia is associated with high prevalence of hypertension, decreased quality of life and poor prognosis. Aldosterone is known as a risk factor for cardiovascular and cerebrovascular diseases. In addition, mineral corticoid receptors are abundantly expressed in the hippocampus, which plays a pivotal role in cognitive function; however, it has not been determined whether plasma aldosterone level is associated with cognitive impairment in patients with hypertension. We enrolled 68 patients with essential hypertension and assessed their cardiovascular risk factors, including blood pressure, hyperlipidemia, diabetes mellitus, obesity, smoking, history of cerebral infarction, renal function, parameters of inflammation, oxidative stress and nitric oxide bioavailability, a parameter of cerebral blood flow and carotid plaque by ultrasound examination, plasma renin activity and plasma aldosterone concentration (PAC). The mini-mental state examination (MMSE) was used to evaluate cognitive function. The relevance of cardiovascular risk factors and MMSE score was statistically evaluated. Multiple regression analysis showed that age (P < 0.01), PAC (P < 0.01) and history of cerebral infarction (P < 0.05) were inversely and independently associated with MMSE score. Mineral corticoid receptor antagonists, including spironolactone and eplerenone, increased MMSE score in seven patients with hypertension, but not in the controls. In conclusion, increased PAC is associated with impaired cognitive function and mineral corticoid receptor blockade may protect against not only cardiovascular mortality, but also cognitive impairment in patients with hypertension.

Activation of peroxisome proliferator-activated receptor α in megakaryocytes reduces platelet-derived growth factor-BB in platelets.

AIM: Platelet-derived growth factor (PDGF)-BB plays a crucial role in atherosclerosis and vascular remodeling by promoting the migration and proliferation of vascular smooth muscle cells. The objective of this study was to clarify the pleiotropic effect of peroxisome proliferator-activated receptor α (PPARα) activators on PDGF-BB expression in megakaryocytes and platelets. METHODS AND RESULTS: The expression of PPARα in a human erythroleukemia (HEL) cells was clearly detected by reverse transcriptase-PCR and immunofluorescence microscopy. The expression level of PPARα in HEL cells was unchanged regardless of differentiation into megakaryocytic cells by treatment with phorbol 12-myristate 13 acetate (TPA). The TPA-induced expression of PDGF-B mRNA and PDGF-BB protein levels in culture media was significantly decreased by treatment with PPARα activators, Wy14643 and fenofibric acid, in a dose-dependent manner. PDGF-BB expression induced by inflammatory cytokines, including interleukin-1ß or interleukin-6, was also significantly suppressed by treatment with PPARα activators. Immunohistochemistry of human bone marrow showed the expression of PPARα in both the nucleus and cytoplasm of megakaryocytes. In addition, PDGF-BB levels in platelets were significantly decreased from 1,800±870 to 1,470±840 pg/10(5) platelets (mean±SD, p<0.05) by treatment with 300 mg fenofibrate once daily for 4 weeks in 13 patients with dyslipidemia. CONCLUSIONS: Activation of PPARα in megakaryocytes reduces PDGF-BB expression in platelets. PPARα activators may exert vasculo-protective action through suppression of PDGF-BB production in a megakaryocyte/platelet pathway.

Effect of low-dose (1 mg/day) pitavastatin on left ventricular diastolic function and albuminuria in patients with hyperlipidemia.

The aim of the present study was to evaluate the factors that modulate the protective action of statins on cardiorenal function, regardless of the lipid-lowering effect. To treat abnormal serum lipid profiles, low-dose pitavastatin (1.0 mg/day) was administered to 65 hyperlipidemic patients. The exclusion criteria included left ventricular ejection fraction <40% and apparent renal disease. Age- and gender-matched patients with hyperlipidemia (n = 40) served as the controls. After 12 to 16 weeks of pitavastatin treatment, pitavastatin had decreased low-density lipoprotein cholesterol (from 143.5 ± 31.4 to 98.2 ± 19.4 mg/dl, p <0.01), triglycerides (from 157.7 ± 57.2 to 140.5 ± 60.7 mg/dl, p <0.01), E/e' (from 10.8 ± 6.2 to 9.0 ± 4.5, p <0.05), a parameter of left ventricular diastolic function, and albuminuria (from 47.6 ± 55.9 to 28.5 ± 40.0 mg/g creatinine, p <0.01). Furthermore, pitavastatin decreased serum transforming growth factor-ß1 (from 709 ± 242 to 550 ± 299 pg/ml, p <0.01), urinary 8-hydroxy-2'-deoxyguanosine (from 6.6 ± 4.1 to 5.0 ± 3.1 µg/g creatinine, p <0.01), an oxidative stress marker, and increased urinary nitrate and nitrite (from 22.5 ± 14.6 to 29.4 ± 27.6 nmol/g creatinine, p <0.05). No such changes were observed in the controls. Multiple regression analysis in the pitavastatin group revealed the effect of pitavastatin on cardiorenal function was associated with suppression of oxidative stress, but not on low-density lipoprotein cholesterol reduction. In conclusion, pitavastatin decreases E/e' and albuminuria, which is associated with suppression of oxidative stress.

Endothelial nitric oxide synthase-independent protective action of statin against angiotensin II-induced atrial remodeling via reduced oxidant injury.

Activation of the renin-angiotensin system exacerbates atrial remodeling, leading to atrial fibrillation and thrombosis, especially in a condition with decreased NO bioavailability. Recently, it has been reported that statins reduce the incidence of atrial fibrillation through attenuation of atrial remodeling; however, the mechanisms have not been completely elucidated. Therefore, we aimed to clarify the beneficial effect of statin on atrial remodeling in condition with reduced NO bioavailability. Endothelial NO synthase(-/-) mice were sham operated or infused with angiotensin II (Ang II) via an osmotic minipump for 2 weeks, and Ang II-infused mice were divided into 3 treatment groups: pitavastatin, Tempol (a free radical scavenger), or vehicle. Echocardiography and electrocardiography showed that Ang II infusion caused left atrial enlargement and a high incidence of atrial fibrillation, whereas pitavastatin and Tempol prevented these abnormalities. In histological analysis, Ang II-induced atrial interstitial fibrosis, perivascular fibrosis, and cardiomyocyte hypertrophy were all attenuated by pitavastatin and Tempol. Immunohistochemical staining showed that Ang II downregulated thrombomodulin and tissue factor pathway inhibitor and upregulated tissue factor and plasminogen activator inhibitor 1 in the left atrium and that pitavastatin and Tempol corrected the thrombogenic condition. Moreover, pitavastatin and Tempol reduced Ang II-induced atrial superoxide production and atrial transforming growth factor-beta1 expression and Smad 2/3 phosphorylation. Atrial rac1-GTPase activity, known to activate NADPH oxidase, was attenuated by pitavastatin but not by Tempol. In conclusion, pitavastatin exerts endothelial NO synthase-independent protective actions against Ang II-induced atrial remodeling and atrial fibrillation with enhanced thrombogenicity through suppression of oxidant injury.

Androgen receptor counteracts Doxorubicin-induced cardiotoxicity in male mice.

Doxorubicin (Dox) has been used as a potent anticancer agent, but serious cardiotoxicity precludes its use in a wide range of patients. We have reported that the androgen-androgen receptor (AR) system plays important roles in cardiac growth and protection from angiotensin II-induced cardiac remodeling. The present study was undertaken to clarify whether the androgen-AR system exerts a cardioprotective effect against Dox-induced cardiotoxicity. Male AR knockout (ARKO) and age-matched littermate male wild-type (WT) mice at 25 wk of age were given ip injections of Dox (20 mg/kg) or a vehicle. The survival rate and left ventricular function in Dox-treated male ARKO mice were reduced compared with those in Dox-treated male WT mice. Electron microscopic study showed prominent vacuole formation of myocardial mitochondria in Dox-treated male ARKO mice. Cardiac oxidative stress and apoptosis of cardiomyocytes were increased more prominently by Dox treatment in male ARKO mice than in male WT mice. In addition, Dox-induced reduction in the expression of cardiac mitochondria transcription factor A (Tfam) and phosphorylation of serine-threonine kinase (Akt) was more pronounced in male ARKO mice than in male WT mice. In cardiac myoblast cells, testosterone up-regulated Akt phosphorylation and Tfam expression and exerted an antiapoptotic effect against Dox-induced cardiotoxicity. Collectively, the results demonstrate that Dox-induced cardiotoxicity is aggravated in male ARKO mice via exacerbation of mitochondrial damage and superoxide generation, leading to enhanced apoptosis of cardiomyocytes. Thus, the androgen-AR system is thought to counteract Dox-induced cardiotoxicity partly through activation of the Akt pathway and up-regulation of Tfam to protect cardiomyocytes from mitochondrial damage and apoptosis.

Heparin cofactor II protects against angiotensin II-induced cardiac remodeling via attenuation of oxidative stress in mice.

Heparin cofactor II (HCII), a serine protease inhibitor, inhibits tissue thrombin action after binding with dermatan sulfate proteoglycans in the extracellular matrix of the vascular system. We previously reported that heterozygous HCII-deficient (HCII(+/-)) humans and mice demonstrate acceleration of vascular remodeling, including atherosclerosis. However, the action of HCII on cardiac remodeling never has been determined. HCII(+/+) and HCII(+/-) mice at age 25 weeks were infused with angiotensin II (Ang II; 2.0 mg/kg/d) for 2 weeks by an osmotic mini-pump. Echocardiography revealed acceleration of cardiac concentric remodeling in HCII(+/-) mice and larger left atrial volume in HCII(+/-) mice than in HCII(+/+) mice. Histopathologic studies showed more prominent interstitial fibrosis in both the left atrium and left ventricle in HCII(+/-) mice than in HCII(+/+) mice. Daily urinary excretion of 8-hydroxy-2'-deoxyguanosine, a parameter of oxidative stress, and dihydroethidium-positive spots, indicating superoxide production in the myocardium, were markedly increased in Ang II-treated HCII(+/-) mice compared to those in HCII(+/+) mice. Cardiac gene expression levels of atrial natriuretic peptides and brain natriuretic peptides, members of the natriuretic peptide family, Nox 4, Rac-1, and p67(phox) as components of NAD(P)H oxidase, and transforming growth factor-beta1 and procollagen III were more augmented in HCII(+/-) mice than in HCII(+/+) mice. However, administration of human HCII protein attenuated all of those abnormalities in Ang II-treated HCII(+/-) mice. Moreover, human HCII protein supplementation almost abolished cardiac fibrosis in Ang II-treated HCII(+/+) mice. The results indicate that HCII has a protective role against Ang II-induced cardiac remodeling through suppression of the NAD(P)H oxidase-transforming growth factor-beta1 pathway.

Ezetimibe ameliorates metabolic disorders and microalbuminuria in patients with hypercholesterolemia.

AIM: Ezetimibe, an inhibitor of Niemann-Pick C1-like 1 protein, has been shown to reduce the intestinal absorption of cholesterol. We investigated whether it also has beneficial effects on metabolic disorder and/or renal insufficiency in patients with hypercholesterolemia. METHODS: Ezetimibe was administered to 38 Japanese patients with hypercholesterolemia to obtain appropriate low-density lipoprotein cholesterol (LDL-chol) levels. Age- and sex-matched patients with hypercholesterolemia (n=38) were the controls. We evaluated the effects of ezetimibe before and 4 to 8 weeks after ezetimibe treatment. RESULTS: Ezetimibe significantly decreased LDL-chol levels and metabolic syndrome-related factors, including body weight, waist circumference, blood pressure; homeostasis model assessment insulin resistance (HOMA-IR), and urinary albumin excretion, were significantly reduced. In addition, it decreased the level of high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor (TNF)-alpha, the urinary excretion of 8-hydroxy-2'-deoxyguanosine, a parameter of oxidative stress, and increased the urinary excretion of nitrate and nitrite (NOx). In the controls we observed no such changes. Excepting the decrease in the serum TNF-alpha level, the effects of ezetimibe were not correlated with decreased LDL-chol levels. CONCLUSION: Ezetimibe ameliorated the status of metabolic syndrome and microalbuminuria, reduced inflammation and oxidative stress, and increased nitric oxide bioavailability in a LDL-chol reduction-dependent and -independent manner.

Androgen-androgen receptor system protects against angiotensin II-induced vascular remodeling.

Age-related andropause promotes cardiovascular disease in males. Although we had previously reported that the androgen-androgen receptor (AR) system plays important roles in cardiac growth and remodeling, the system's involvement in vascular remodeling remains unclear. To clarify this role, 25-wk-old male AR knockout (ARKO) mice and littermate male wild-type (WT) mice were divided into two groups with and without angiotensin II (Ang II) administration (2.0 mg/kg . d) for 14 d, respectively. No morphological differences in the coronary artery and thoracic aorta were observed between the groups without Ang II. Ang II stimulation markedly increased medial thickness and perivascular fibrosis in ARKO mice, with enhanced TGF-beta1, collagen type I, and collagen type III gene expression in the aorta. Ang II stimulation also prominently increased superoxide production, lipid peroxidation, and gene expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase components in ARKO mice compared with WT mice. In addition, phosphorylation of c-Jun N-terminal kinase (JNK) and phosphorylated (Smad2/3) was remarkably enhanced in Ang II-treated ARKO mice compared with Ang II-treated WT mice. Notably, daily urinary nitric oxide (NO) metabolites excretion as a marker of NO bioavailability, aortic endothelial NO synthase expression and phosphorylation, and Akt phosphorylation were significantly reduced in ARKO mice compared with WT mice, regardless of Ang II stimulation. In conclusion, the androgen-AR system is required for the preservation of NO bioavailability through Akt-endothelial NO synthase system activation and exerts protective effects against Ang II-induced vascular remodeling by regulating oxidative stress, c-Jun N-terminal kinase (JNK) signaling, and the TGF-beta-phosphorylated Smad pathway.

Heparin cofactor II is an independent protective factor against peripheral arterial disease in elderly subjects with cardiovascular risk factors.

AIM: Heparin cofactor II (HCII) specifically inactivates thrombin action at the injured vascular wall. We have reported that HCII is a protective factor against coronary in-stent restenosis and carotid atherosclerosis; however, it is unclear whether there is any correlation between plasma HCII levels and the development of peripheral arterial disease (PAD). METHODS: Plasma HCII activity and the ankle brachial pressure index (ABI) were determined in 494 elderly subjects with cardiovascular risk factors. PAD was diagnosed by ABI below 0.9, and 62 subjects were diagnosed with PAD. The relationship between factors that affect cardiovascular events and the prevalence of PAD was statistically evaluated. RESULTS: Mean HCII activity in PAD subjects was significantly lower than in non-PAD subjects (87.5+/-19.7% v.s. 94.6+/-17.8%, p=0.009). Multivariate logistic regression analysis showed that age (odds ratio [OR]: 1.062, p=0.0016), current smoking (OR 3.028, p=0.002) and diabetes mellitus (OR 2.656, p=0.008) were independent and progressive determinants of PAD. In contrast, HCII was an independent inhibitory factor of PAD (OR: 0.982, p=0.048). CONCLUSIONS: Plasma HCII activity is inversely related to the prevalence of PAD. HCII may function as the sole protective factor against PAD in elderly people with cardiovascular risk factors.