Strain-dependent embryonic lethality and exaggerated vascular remodeling in heparin cofactor II-deficient mice.

Heparin cofactor II (HCII) specifically inhibits thrombin action at sites of injured arterial wall, and patients with HCII deficiency exhibit advanced atherosclerosis. However, the in vivo effects and the molecular mechanism underlying the action of HCII during vascular remodeling remain elusive. To clarify the role of HCII in vascular remodeling, we generated HCII-deficient mice by gene targeting. In contrast to a previous report, HCII(-/-) mice were embryonically lethal. In HCII(+/-) mice, prominent intimal hyperplasia with increased cellular proliferation was observed after tube cuff and wire vascular injury. The number of protease-activated receptor-1-positive (PAR-1-positive) cells was increased in the thickened vascular wall of HCII(+/-) mice, suggesting enhanced thrombin action in this region. Cuff injury also increased the expression levels of inflammatory cytokines and chemokines in the vascular wall of HCII(+/-) mice. The intimal hyperplasia in HCII(+/-) mice with vascular injury was abrogated by human HCII supplementation. Furthermore, HCII deficiency caused acceleration of aortic plaque formation with increased PAR-1 expression and oxidative stress in apoE-KO mice. These results demonstrate that HCII protects against thrombin-induced remodeling of an injured vascular wall by inhibiting thrombin action and suggest that HCII is potentially therapeutic against atherosclerosis without causing coagulatory disturbance.

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.

Decrease in plasma brain natriuretic peptide level in the early phase after the start of carvedilol therapy is a novel predictor of long-term outcome in patients with chronic heart failure.

OBJECTIVE: The purpose of the present study was to determine whether change in plasma brain natriuretic peptide (BNP) level at an early phase of carvedilol therapy is a predictor of improvement in cardiac function and long-term prognosis in patients with systolic chronic heart failure (CHF). METHODS AND RESULTS: Neurohumoral factors and haemodynamics were examined in 64 patients with systolic CHF (left ventricular ejection fraction (LVEF) below 45%) before and one month (early phase) and 3 to 6 months (late phase) after the start of carvedilol therapy. These patients were followed up for a mean period of 57 months. Plasma BNP levels were already decreased in the early phase before improvement of LVEF in response to carvedilol therapy. Univariate and multivariate linear regression analyses showed that Delta log brain natriuretic peptide (BNP)E (= log BNP at baseline--log BNP at early phase) (P < 0.0001) was a significant independent predictor of improvement in LVEF in the late phase. Cardiac events occurred in I I patients during the follow-up period. In addition, multivariate Cox proportional hazards regression analysis showed that Delta log BNPE (P = 0.0045) and systolic blood pressure at baseline (P = -0.048) were significant independent predictors of the development of cardiac events. CONCLUSIONS: Decrease in plasma BNP level in the early phase of carvedilol therapy is a novel predictor of not only improvement of LVEF in the late phase but also prognosis in patients with systolic CHF.

Delayed motor and sensory neuropathy in a patient with brainstem encephalitis.

Bickerstaff's brainstem encephalitis (BBE), Miller Fisher syndrome (MFS) and Guillain-Barré syndrome (GBS) are thought to be closely related and to form a continuous spectrum. However, chronic polyneuropathy in BBE has not been reported. We report the temporal profile of anti-ganglioside antibody titer in a case of BBE-like brainstem encephalitis complicated with chronic polyneuropathy. A 71-year-old Japanese woman presented with drowsiness and cerebellar ataxia in addition to mild weakness in distal limb muscles. Anti-GalNAc-GD1a IgG and anti-GalNAc-GM1b IgG antibodies were positive in her serum. Brain magnetic resonance imaging revealed high-intensity signals in the midbrain, pons, and middle cerebellar peduncles on T2-weighted images. Central nervous system manifestations improved after immunomodulating therapy that included prednisolone, plasmapheresis and intravenous immunoglobulin. Nevertheless, the distal muscle weakness was exacerbated when the anti-GalNAc-GD1a IgG titer was elevated. Nerve conduction study indicated motor and sensory neuropathy which was developed motor dominant axonal damage. These findings suggest that anti-ganglioside antibodies, including anti-GalNAc-GD1a IgG, may be involved in a common autoimmune mechanism in BBE-like brainstem encephalitis and chronic motor dominant axonal neuropathy. However, the fact that the latter manifestation exacerbated after the improvement of former one possibly indicates different thresholds of neurologic symptoms mediated by anti-ganglioside antibodies in the present patient.

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.

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.

Infective endocarditis caused by lactobacillus.

Lactobacillus (LB) is a gram-positive rod-shaped bacterium that inhabits the oral cavity, gastrointestinal tract, vagina and nasal cavity. Although LB plays a role in the prevention of infections caused by pathogenic bacteria, it causes some critical infectious diseases such as infective endocarditis (IE). IE due to LB is rare; however, early diagnosis and early treatment are important because of its high mortality rate. We report the onset of IE after otologic treatment in a heavy drinker of alcohol, the second case of IE due to LB in Japan.

Improvement of cardiac diastolic function and prognosis after autologous peripheral blood stem cell transplantation in AL cardiac amyloidosis.

AL amyloidosis is a disease in which immunoglobulin L chain is deposited in multiple organs, and the prognosis of cardiac amyloidosis is extremely poor. Although several treatments based on that for multiple myeloma, have been performed, there is no clear evidence that cardiac function is improved. We report a case of AL cardiac amyloidosis with moderate cardiac dysfunction for which we performed autologous peripheral blood stem cell transplantation (auto-PBSCT) in combination with high-dose melphalan therapy. This treatment resulted in significant improvement in cardiac function and good prognosis for about 3.5 years after the diagnosis. Therefore, auto-PBSCT is a possible option as up-front therapy for AL cardiac amyloidosis.