Activation of proprotein convertase in the mouse habenula causes depressive-like behaviors through remodeling of extracellular matrix

The lateral habenula (LHb) attracts a growing interest as a regulator of monoaminergic activity which were frequently reported to be defective in depression. Here we found that chronic social defeat stress (CSDS) increased production of pro-inflammatory cytokines in LHb associated with mobilization of monocytes and remodeling of extracellular matrix by increased matrix metalloproteinase (MMP) activity. RNA-seq analysis identified proprotein convertase Pcsk5 as an upstream regulator of MMP activation, with upregulation in LHb neurons of mice with susceptibility to CSDS. PCSK5 facilitated motility of microglia in vitro by converting inactive pro-MMP14 and pro-MMP2 to their active forms, highlighting its role in mobilization of microglia and monocytes in neuroinflammation. Suppression of Pcsk5 expression via small interfering RNA (siRNA) ameliorated depressive-like behaviors and pathological mobilization of monocytes in mice with susceptibility to CSDS. PCSK5-MMPs signaling pathway could be a target for development of the antidepressants targeting the inflammatory response in specific brain regions implicated in depression.Subject terms: Cellular neuroscience, Gene expression analysis     

Factors predicting the response to low-dose methotrexate therapy in patients with rheumatoid arthritis: a better response in male patients

Methotrexate (MTX) is the most commonly used disease-modifying antirheumatic drug (DMARD) throughout the world. In Japan, MTX is recommended by the Japanese Ministry of Health, Labour, and Welfare to be given as the second or third DMARD and at a dosage of no more than 8 mg/week. We analyzed the efficacy of MTX in Japanese patients with RA in order to determine whether it is comparable to that in Western countries, where 15–20 mg/week of MTX is used, as well as to elucidate the factors associated with the favorable response to MTX. Around 8 mg/week of MTX was effective in half of the RA patients in the current study, and male sex was the only factor associated with a good response to MTX from a multivariate regression model analysis. Some of the patients who had a poor response to MTX showed an improvement with the addition of bucillamine or prednisolone. For the remaining patients, an increase in the MTX dosage to more than 8 mg/week or the use of biologics such as the anti-tumor necrosis factor (TNF)-α monoclonal antibody may be required.     

Cardiac angiotensin II type 2 receptor activates the kinin/NO system and inhibits fibrosis

We have previously demonstrated that stimulation of the angiotensin (Ang) II type 2 receptor in vascular smooth muscle cells caused bradykinin production by activating kininogenase in transgenic mice. The aim of this study was to determine whether overexpression of AT2 receptors in cardiomyocytes attenuates Ang II-induced cardiomyocyte hypertrophy or interstitial fibrosis through a kinin/nitric oxide (NO)-dependent mechanism in mice. Ang II (1.4 mg/kg per day) or vehicle was subcutaneously infused into transgenic mice and wild-type mice for 14 days. The amount of cardiac AT2 receptor relative to AT1 receptor in transgenic mice was 22% to 37%. Ang II caused similar elevations in systolic blood pressure (by approximately 45 mm Hg) in transgenic mice and wild-type mice. Myocyte hypertrophy assessed by an increase in myocyte cross-sectional area, left ventricular mass, and atrial natriuretic peptide mRNA levels were similar in transgenic and wild-type mice. Ang II induced prominent perivascular fibrosis of the intramuscular coronary arteries, the extent of which was significantly less in transgenic mice than in wild-type mice. Inhibition of perivascular fibrosis in transgenic mice was abolished by cotreatment with HOE140, a bradykinin B2 receptor antagonist, or L-NAME, an inhibitor of NO synthase. Cardiac kininogenase activity was markedly increased (approximately 2.6-fold, P<0.001) after Ang II infusion in transgenic mice but not in wild-type mice. Immunohistochemistry indicated that both bradykinin B2 receptors and endothelial NO synthase were expressed in the vascular endothelium, whereas only B2 receptors were present in fibroblasts. These results suggest that stimulation of AT2 receptors present in cardiomyocytes attenuates perivascular fibrosis by a kinin/NO-dependent mechanism. However, the effect on the development of cardiomyocyte hypertrophy was not detected in this experimental setting.     

Increased bone resorption may play a crucial role in the occurrence of osteopenia in patients with type 2 diabetes: Possible involvement of accelerated polyol pathway in its pathogenesis

In order to investigate the underlying mechanism of alterations in bone mineral metabolism in patients with type 2 diabetes, we determined circulating levels of bone functional markers along with urinary excretion of sorbitol (SOR) and bone mineral density (BMD), and also examined their mutual interrelationship. A total of 151 male type 2 diabetic patients were examined in this study. Forty-eight age-matched male healthy subjects were also studied as the controls. A significant reduction of serum intact osteocalcin (i-OC) was found in the diabetic groups (p<0.01). On the other hand, circulating levels of tartrate resistant acid phosphatase (TRAP) in the diabetic patients were significantly higher than those in the controls (p<0.01). Interestingly, a significantly negative relationship was observed between BMD and serum TRAP (p<0.01), although no significant relationship was noted between BMD and serum i-OC in diabetic patients. Urinary excretion of SOR was significantly elevated in the diabetic patients when compared with the controls (p<0.01). In addition, a significantly positive correlation was observed between serum TRAP and urinary SOR (p<0.01), but not between serum i-OC and urinary SOR. Elevated serum TRAP in diabetes was reduced after the administration of aldose reductase inhibitor (p<0.05). It seems most likely that the increase in osteoclastic function probably due to accelerated polyol pathway plays a crucial role in the pathogenesis of decreased bone mineral content in male patients with type 2 diabetes.     

Clinicopathologic differences between early gastric remnant cancer and early primary gastric cancer in the upper third of the stomach

BACKGROUND/AIMS: This study was designed to clarify the clinicopathologic characteristics and survival in early gastric remnant cancer and compare with early primary cancer in the upper third of the stomach. METHODOLOGY: Twenty-five patients with early gastric remnant cancer, who underwent resection at Kanagawa Cancer Center and First Department of Surgery, Yokohama City University between 1974 and 1996 were evaluated in this study. Various clinicopathologic characteristics, such as age, sex, symptoms, size of tumor, depth of invasion, lymph node metastasis, cell differentiation, and survival were investigated and early gastric remnant cancer was compared with early primary cancer in the upper third of the stomach. RESULTS: According to the macroscopic type, protruded type such as I or II type accounted for a great majority in early gastric remnant cancer, while II c depressed type was common in early primary cancer in the upper third of the stomach, comprising 64.2% of all cases. Pathological examination disclosed that well-differentiated carcinoma and mucosal carcinoma were more frequently observed in early gastric remnant cancer than in early primary cancer in the upper-third of the stomach. The 5-year survival rate was 83.5% for early primary cancer in the upper-third of the stomach. In contrast, no patients experienced recurrence after operation for early gastric remnant cancer. CONCLUSIONS: From the view point of clinicopathological evaluation, gastric remnant cancer is a special from of gastric cancer. A follow-up program is important in order to detect early gastric remnant cancer. A low incidence of lymph node metastasis suggests that endoscopic mucosal resection of the tumor or limited operation could be performed under strict indication.     

Altered relationship between body fat and plasma adiponectin in end-stage renal disease

Patients with end-stage renal disease (ESRD) show an inverse association between body mass index and risk of death from cardiovascular disease. Paradoxical epidemiology may suggest some beneficial effects of body fat in ESRD. Because an antiatherogenic adipocytokine adiponectin is increased in uremic plasma, we tested a hypothesis that, in ESRD, plasma adipocytokine profile may be less atherogenic or that the relationship between body fat and adipocytokines may be altered. The subjects were 103 patients with ESRD undergoing hemodialysis and 166 healthy subjects comparable in age and sex. We measured body fat mass by dual-energy x-ray absorptiometry and plasma levels of adiponectin and leptin by enzyme-linked immunosorbent assay. The ESRD group showed a significant increase in plasma adiponectin, leptin, and adiponectin/leptin ratio than the healthy subjects. Although sex and fat mass were significant factors correlating with plasma adiponectin level in the healthy group, none of these were significantly associated with plasma adiponectin in the patients with ESRD. In contrast, leptin showed significant relationships with sex and fat mass regardless of the presence of ESRD. Plasma adiponectin correlated negatively with plasma triglycerides and positively with high-density lipoprotein cholesterol in both healthy and ESRD groups, suggesting that uremic adiponectin retains its actions in favor of its antiatherogenicity. Thus, plasma adipocytokine profile was altered in ESRD, and the effects of body fat and sex on adiponectin were less significant in the patients with ESRD.     

Perioperative management of benign hepatic tumors in patients with glycogen storage disease type Ia

Glycogen storage disease type Ia (GSD-Ia; von Gierke disease) is an inherited disorder caused by glucose-6-phosphatase deficiency, and there have been some reports of hepatic tumors in patients with this disease. We report two patients with benign hepatic tumors with GSD-Ia. One is a 19-year-old man who underwent segmentectomy 4 for a focal nodular hyperplasia, and the other is a 31-year-old woman who underwent segmentectomies 3, 5, and 6 for hepatic adenomas. Two significant perioperative complications, resulting from the carbohydrate metabolic disorders, hypoglycemia and metabolic acidosis, occurred in both patients. We managed the metabolic complications successfully by administering a sufficient volume of glucose intravenously. Close perioperative monitoring of blood glucose and lactate concentrations is essential in the perioperative management of patients with GSD-Ia. The intravenous administration of glucose, starting with a smaller dose and then increasing the dose, is adequate management for lactic acidosis with or without hypoglycemia during the perioperative period.     

Survey to determine the efficacy and safety of guideline-based pharmacological therapy for chronic obstructive pulmonary disease patients not previously receiving maintenance treatment

Objective: To investigate the potential beneficial effects of guideline-based pharmacological therapy on pulmonary function and quality of life (QOL) in Japanese chronic obstructive pulmonary disease (COPD) patients without prior treatment.

Research design and methods: Multicenter survey, open-label study of 49 Japanese COPD patients aged ≥ 40 years; outpatients with >10 pack years of smoking history; ratio of forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) < 70%; predicted FEV₁ < 80%; treated with bronchodilators and/or inhaled corticosteroids as maintenance therapy until week 48.

Main outcome measures: The primary endpoint was change in pulmonary function (trough FEV₁, trough FVC); secondary endpoints were QOL and physical activity at 48 weeks after initiation of therapy.

Results: Airway reversibility was confirmed in untreated patients. Significant changes over time were not observed for FEV₁ and FVC, indicating lung function at initiation of treatment was maintained during the observation period. COPD assessment test scores showed statistical and clinical improvements. Cough, sputum, breathlessness, and shortness of breath were significantly improved.

Conclusions: Lung function and QOL of untreated Japanese COPD patients improved and improvements were maintained by performing a therapeutic intervention that conformed to published guidelines.