Endotheliopathy of liver sinusoidal endothelial cells in liver disease

Liver is the largest solid organ in the abdominal cavity, with sinusoid occupying about half of its volume. Under liver disease, hemodynamics in the liver tissue dynamically change, resulting in injury to liver sinusoidal endothelial cells (LSECs). We discuss the injury of LSECs in liver diseases in this article. Generally, in noninflamed tissues, vascular endothelial cells maintain quiescence of circulating leukocytes, and unnecessary blood clotting is inhibited by multiple antithrombotic factors produced by the endothelial cells. In the setting of inflammation, injured endothelial cells lose these functions, defined as inflammatory endotheliopathy. In chronic hepatitis C, inflammatory endotheliopathy in LSECs contributes to platelet accumulation in the liver tissue, and the improvement of thrombocytopenia by splenectomy is attenuated in cases with severe hepatic inflammation. In COVID-19, LSEC endotheliopathy induced by interleukin (IL)-6 trans-signaling promotes neutrophil accumulation and platelet microthrombosis in the liver sinusoids, resulting in liver injury. IL-6 trans-signaling promotes the expression of intercellular adhesion molecule-1, chemokine (C-X-C motif) ligand (CXCL1), and CXCL2, which are the neutrophil chemotactic mediators, and P-selectin, E-selectin, and von Willebrand factor, which are involved in platelet adhesion to endothelial cells, in LSECs. Restoring LSECs function is important for ameliorating liver injury. Prevention of endotheliopathy is a potential therapeutic strategy in liver disease.     

Biological and clinical significance of hepatocyte growth factor in breast cancer

Hepatocyte growth factor (HGF) is a mesenchyme- or stroma-derived multipotent factor that regulates the growth, motility, and morphogenesis of various types of cells, including cancer cells. We investigated the effect of HGF on human breast cancer cells, and measured the concentration of HGF in the sera of breast cancer patients. When BT-20 cells were stimulated with HGF, the transmigration of cancer cells was markedly accelerated. In a checkboard assay, pronounced chemotaxic locomotion of BT-20 cells is expressed, corresponding to HGF concentrations. HGF treatment of BT-20 cells resulted in enhanced expression of alpha 2, alpha 3 and beta 1 integrin subunits, and augmented the binding activity to immobilized collagen. The c-met protein was expressed on the cancer cells in 48 of the 97 (49.5%) breast cancer primary tumors. In the serum, the advanced and recurrent cancer group showed a high level of this protein in comparison with the other patient groups. The mean value of serum HGF was 0.65 ng/ml in patients with distant metastases and 0.27 ng/ml in those with no such evidence. Thus, the HGF concentration becomes significantly elevated in the sera of patients with distant metastases. These findings suggest that HGF is involved in invasion and metastasis of breast cancer, and that serum HGF is useful as a tumor marker with a close correlation to the metastatic state of breast cancer.     

Cytosol and serum concentration of cytokeratin subunit-19 fragment (cyfra-21-1) in breast-cancer

Cytokeratin 19 is a subunit of cytokeratin intermediate filament. CYFRA 21-1 is a new tumor marker using monoclonal antibodies which recognize a fragment of cytokeratin 19. CYFRA 21-1 was measured in cytosol of breast cancer tissues or in sera of patients with breast cancer or benign breast diseases to study the significance of this protein as a tumor marker. The cytosol concentration of CYFRA 21-1 was elevated in cancerous tissue compared to that in adjacent noncancerous tissue, and correlated with the tumor stage or the estrogen receptor status. In the serum, the mean value and positive rate for CYFRA 21-1 (assuming 2.2 ng/ml as the cut-off value) were 0.61 ng/ml (0%) in benign breast diseases, 0.98 ng/ml (6.7%) in stage I/II primary breast cancer, 75.67 ng/ml (60.0%) in stage III/IV primary breast cancer, 45.28 ng/ml (60.0%) in recurrent breast cancer, and 0.64 ng/ml (2.6%) in those with no evidence of recurrence. From the above, we concluded that CYFRA 21-1 could be a tumor marker with high specificity in breast cancer.     

Characteristics of myocardial ischemia in patients with chronic renal failure and its relation to cardiac sympathetic activity

In order to clarify the characteristics of myocardial ischemia in patients with chronic renal failure (CRF), we performed exercise stress myocardial perfusion imaging with 99mTc-MIBI in 36 patients with CRF. In 18 patients myocardial imaging with 123I-MIBG (MIBG) and 201Tl was performed at rest to evaluate myocardial sympathetic activities: cardiac uptake of MIBG normalized by myocardial perfusion (Uptake Ratio, UR) and myocardial washout rate of MIBG (WO). Exercise-induced perfusion abnormality was observed in 25 patients, and coronary angiography was performed in 19 of them. Among 25 diseased coronary arteries, 18 developed perfusion abnormalities in the myocardial segments which were supplied by each coronary artery. However in 5 patients without coronary artery stenosis and 2 patients with left anterior descending coronary artery disease, transient perfusion abnormalities were observed in the inferior segments. In 6 of them, MIBG imaging was obtained (Group A). MIBG imaging was also performed in 5 patients with transient inferior perfusion abnormality with coronary artery stenosis which supplied the inferior wall (Group B), and 7 patients without perfusion abnormality (Group C). In the patients of Group B, inferior UR was significantly lower than in Group C (0.58 +/- 0.07 vs. 0.68 +/- 0.08, p = 0.0485) and inferior WO was more accelerated than in Group C (18.6 +/- 7.7 vs. 12.1 +/- 6.0%, NS). However anterior UR and Wo levels were identical with those in Group C. In Group A, inferior UR (0.43 +/- 0.05) was significantly lower than in Group B and C, and WO in Group A (27.2 +/- 8.3%) was accelerated significantly compared to that in Group C. Besides in Group A, anterior UR was significantly smaller and WO was greater than in Group B and C. These findings suggested that in some patients with CRF, myocardial ischemia could arise without coronary artery stenosis, and this phenomenon might be related to abnormalities of cardiac sympathetic activity.     

Lack of association between the heparan sulfate proteoglycan gene polymorphism and diabetic nephropathy in Japanese NIDDM with proliferative diabetic retinopathy

The development of diabetic nephropathy shows remarkable variation among individuals. Therefore, not only hyperglycemia but also genetic factors may contribute to the development of diabetic nephropathy Heparan sulfate proteoglycan (HSPG) is thought to play an important role as a component of the charge selectivity barrier in the glomerular basement membrane. Recently, a BamHI restriction fragment length polymorphism (RFLP) in the HSPG gene (HSPG2) was reported to be associated with diabetic nephropathy in Caucasian insulin-dependent diabetes mellitus (IDDM). The aim of the present study was to examine the contribution of the BamHI HSPG2 polymorphism to the development of diabetic nephropathy in Japanese non-insulin-dependent diabetes mellitus (NIDDM). For this purpose, we recruited 102 patients with diabetic nephropathy and 64 age-matched patients without diabetic nephropathy from Japanese NIDDM patients. Since all the subjects had proliferative diabetic retinopathy, it seems likely that they would be exposed to hyperglycemia for a long time. In the present study, the BamHI HSPG2 genotype and allele frequencies were not significantly different between the patients with nephropathy and the patients without nephropathy. Therefore, we conclude that the BamHI HSPG2 polymorphism is not associated with the development of diabetic nephropathy in Japanese NIDDM.     

Centrally nucleated fibers (CNFs) compensate the fragility of myofibers in mdx mouse

Centrally nucleated fibers (CNFs) are the myofibers which have nuclei in the center of cytoplasm, and are generally recognized as regenerated myofibers. They are commonly observed in the histopathology of the patients with several types of muscular dystrophies and their animal models. In the mdx mouse, an animal model of Duchenne muscular dystrophy, CNFs are more resistant than non-CNFs to mechanical stresses, as evidenced by the Evans blue infiltration. In relation to the population among muscles, CNFs are supposed to compensate the fragility of muscular tissue in muscular dystrophies and their animal models.     

Effects of protein meals on the urinary excretion of various plasma proteins in healthy subjects

To examine whether hemodynamic changes in response to acute protein loadings with different protein sources cause increases in urinary excretion of plasma proteins in healthy subjects, urinary excretions of various plasma proteins with various molecular radii and isoelectric points, namely albumin (Alb), IgG, IgG4, ceruloplasmin (CRL), and alpha2-macroglobulin (A2), were measured in healthy subjects after ingestion of a beef meal or of a tuna fish meal. Significant increases in urinary excretions of the negatively charged IgG4 and CRL and of the neutrally charged IgG were found in parallel with enhanced creatinine clearances after each protein ingestion. These renal responses returned to basal levels 9 h after the test. This finding suggests that in healthy subjects, the increase in glomerular filtration rate after acute protein loading caused selective enhancement of urinary excretions of plasma proteins with a molecular radius of approximately 55 A (the radius of IgG, IgG4, and CRL), irrespective of the charge barrier of the glomerulus. The increases in these three plasma proteins may be induced by leakage via the shunt pathway in the glomerulus, as proposed earlier (see text). In contrast, increases in urinary excretions of A2 and Alb were not found. The former finding may be explained by the possibility that A2 would not pass through this pathway, since the molecular radius of A2 (88 A) is larger than that of IgG, although the latter finding may be partially explained by preferential renal tubular reabsorption of Alb.     

The modulatory effect of (+)-TAN-67 on the antinociceptive effects of the nociceptin/orphanin FQ in mice

To clarify the pharmacological properties of (+)2-Methyl-4aalpha-(3-hydroxyphenyl)-1, 2, 3, 4, 4a, 5, 12, 12aalpha-octahydro-quinolino[2, 3, 3-g]isoquinoline ((+)-TAN-67), the effect of (+)-TAN-67 on the antinociception induced by the intrathecal (i.t.) administration of nociceptin/orphanin FQ was studied in mice using the tail-flick test and the formalin test. I.t. administration of (+)-TAN-67, at doses of 1 to 10 ng, facilitated the tail-flick response in a dose-dependent manner in mice. In addition, i.t. administration of (+)-TAN-67 (1 to 10 ng) in mice produced a marked pain-like aversive responses. I.t. pretreatment with D-Pro(9)-[spiro-gamma-lactam]-Leu(10)-Trp(11)-physalaemin(1-11) (GR82334, 0.1-1.0 nmol), a potent and selective tachykinin NK(1) receptor antagonist, dose-dependently blocked the reduction of the tail-flick response induced by (+)-TAN-67. Furthermore, (+)-TAN-67-induced facilitation of the tail-flick response was abolished in capsaicin-treated mice. On the other hand, (+)-TAN-67-induced flinching responses were dose-dependently and significantly reduced by i.t. pretreatment with GR82334 (0.1-1.0 nmol). The duration of i.t. (+)-TAN-67-induced flinching responses was significantly reduced in capsaicin-treated mice as compared with naive mice. I.t. administration of nociceptin/orphanin FQ (1-10 nmol) dose-dependently increased the tail-flick latency. I.t. administration of nociceptin/orphanin FQ (0.1-1.0 nmol) significantly and dose-dependently reduced the first-phase nociceptive response, but not the second-phase nociceptive response. I.t. pretreatment with (+)-TAN-67 (0.3-3.0 microg) for 30 min dose-dependently attenuated the antinociception induced by i.t. nociceptin (10 nmol) in the tail-flick test. Furthermore, the antinociceptive effect of nociceptin/orphanin FQ (1 nmol, i.t.) on the first-phase response in the formalin test was dose-dependently attenuated by s.c. pretreatment with (+)-TAN-67 (0.3-3.0 microg). (+)-TAN-67 (0.3-3.0 microg, i.t.), by itself, did not facilitate the tail-flick response or produce apparent behavioral changes. It is possible that (+)-TAN-67 has an antagonistic effect on nociceptin/orphanin FQ-induced antinociception.     

Adhesion molecules involved in pleural dissemination of esophageal cancer cells

Pleural dissemination is a common cause of recurrence after surgery of patients with esophageal cancer. Very little is known about the biochemical processes involved in the initial attachment of cancer cells to pleural mesothelial cells. The authors conducted in vitro and in vivo studies to assess the role of adhesion molecules in this process, using 2 cell lines derived from human esophageal cancer. TE-1 cells, which pronouncedly express CD44H, adhered to the monolayers of mesothelial cells more firmly than T.Tn cells. On the other hand, the adhesion of TE-I cells to mesothelial cells was markedly inhibited by antibodies to CD44H or the beta(1) integrin subunit, and more strongly blocked by using a combination of the two antibodies. These antibodies inhibited the dissemination of TE-1 cells in the pleural cavity of nude mice. The findings suggest that CD44 and integrin play important roles in the initial attachment of esophageal cancer cells to mesothelial cells.