Dendritic fields of spinal motoneurons (MNs) are popularly believed to be stellate; however, variation in dendritic arborization, especially concerning the innervated muscle groups, has not been ...systematically studied. We addressed this problem by injecting Neurobiotin through patch-pipettes into single MNs (rat cervical cord slices) that had been retrogradely labelled from innervated muscle groups situated along a proximal (here named "scapular" including serratus anterior) to distal (forearm) axis. MNs had fairly straight dendrites with small numbers of mainly proximal branches that exhibited acute branch angles, leaving large areas around the cells with no dendrites. MNs in the same group of pools showed similar morphologies, but there were clear differences among groups. Forearm MNs (n = 35) showed hemidirectionally-extended multipolar dendrites, whereas scapular MNs (n = 15) had bipolar dendrites, and pectoralis MNs (n = 20) had an intermediate morphology. MNs thus showed a spectrum of morphologic characteristics along the axis. This may be because more distally-located forearm muscles are involved in finer movements and need a wider variety of inputs for neural control than proximally-located muscles. We also devised a quantitative method for evaluating the degree to which a cell's dendritic field displays a symmetric spherical shape; only 20% of MNs tested reached this criterion.
Restoration of blood flow in skeletal muscle after a prolonged period of ischemia induces muscular ischemia–reperfusion injury, leading to local injury/dysfunction in muscles followed by systemic ...inflammatory responses. However, preventive/curative agents for skeletal muscle ischemia injury are unavailable in clinics to date. Increasing evidence has validated that carbon monoxide (CO) prevents the progression of ischemia–reperfusion injury in various organs owing to its versatile bioactivity. Previously, we developed a bioinspired CO donor, CO-bound red blood cells (CO-RBC), which mimics the dynamics of RBC-associated CO in the body. In the present study, we have tested the therapeutic potential of CO-RBC in muscular injury/dysfunction and secondary systemic inflammation induced by skeletal muscle ischemia–reperfusion. The results indicate that CO-RBC rather than RBC alone suppressed elevation of plasma creatine phosphokinase, a marker of muscular injury, in rats subjected to both hind limbs ischemia–reperfusion. In addition, the results of the treadmill walking test revealed a significantly decreased muscular motor function in RBC-treated rats subjected to both hind limbs ischemia–reperfusion than that in healthy rats, however, CO-RBC treatment facilitated sustained muscular motor functions after hind limbs ischemia–reperfusion. Furthermore, CO-RBC rather than RBC suppressed the production of tumour necrosis factor (TNF)-α and interleukin (IL)-6, which were upregulated by muscular ischemia–reperfusion. Interestingly, CO-RBC treatment induced higher levels of IL-10 compared to saline or RBC treatments. Based on these findings, we suggest that CO-RBC exhibits a suppressive effect against skeletal muscle injury/dysfunction and systemic inflammatory responses after skeletal muscle ischemia–reperfusion.
Aims: High levels of high-density lipoprotein cholesterol (HDL-C) are not necessarily effective in preventing atherosclerotic cardiovascular disease, and cholesterol efflux capacity (CEC) has ...attracted attention regarding HDL functionality. We aimed to elucidate whether drinking habits are associated with CEC levels, while also paying careful attention to confounding factors including serum HDL-C levels, other life style factors, and rs671 (＊2), a genetic polymorphism of the aldehyde dehydrogenase 2 (ALDH2) gene determining alcohol consumption habit.Methods: A cross-sectional study was performed in 505 Japanese male subjects who were recruited from a health screening program. Associations of HDL-C and CEC levels with drinking habits and ALDH2 genotypes were examined.Results: The genotype frequencies of ALDH2 ＊1/＊1 (homozygous wild-type genotype), ＊1/＊2 and ＊2/＊2 (homozygous mutant genotype) were 55%, 37% and 8%, respectively. Both HDL-C and CEC levels were higher in ALDH2 ＊1/＊1 genotype carriers than in ＊2 allele carriers. Although HDL-C levels were higher in subjects who had a drinking habit than in non-drinkers, CEC levels tended to be lower in subjects with ≥ 46 g/day of alcohol consumption than in non-drinkers. Furthermore, CEC levels tended to be lower in ALDH2 ＊1/＊1 genotype carriers with a drinking habit of ≥ 46 g/day than non-drinkers, while for ＊2 allele carriers, CEC levels tended to be lower with a drinking habit of 23-45.9 g/day compared to no drinking habit.Conclusions: Our results suggest that heavy drinking habits may tend to decrease CEC levels, and in the ALDH2 ＊2 allele carriers, even moderate drinking habits may tend to decrease CEC levels.
Kupffer cells are a major producer of reactive oxygen species and have been implicated in the development of liver fibrosis during chronic hepatitis in non-alcoholic steatohepatitis (NASH) and ...alcoholic steatohepatitis (ASH). We recently reported on the development of a polythiolated and mannosylated human serum albumin (SH-Man-HSA) that functions as a Kupffer cell-targeting nanoantioxidant. In this material, the albumin is mannosylated, which permits it to be taken up by mannose receptor C type 1 expressed on Kupffer cells, and is also polythiolated to have antioxidant activity. To clarify the anti-fibrotic property of this nanoantioxidant, we repeatedly administered SH-Man-HSA to a liver fibrosis mouse model that was induced by the repeated treatment of the concanavalin-A, which mimics the liver fibrosis observed in NASH and ASH. SH-Man-HSA dramatically improved the survival rate and suppressed liver fibrosis in the experimental model. In addition, SH-Man-HSA suppressed hepatic oxidative stress levels, thereby decreasing the numbers of apoptotic cells. In contrast, N-acetylcysteine, which contains the same thiol content as the SH-Man-HSA, failed to show a substantial therapeutic effect in these mice. The expression levels of inflammatory genes including epidermal growth factor module-containing mucin-like receptor (Emr-1/F4/80), Toll-like receptor-4 (TLR-4), high mobility group box-1 (HMGB-1), CC chemokine ligand-5 (CCL-5), tumor necrosis factor-α (TNF-α), CCL-2, interleukin-6 (IL-6), and IL-1β, as well as fibrotic (α-smooth muscle actin (α-SMA), transforming growth factor-β (TGF-β), and Snail) and extracellular matrix genes (collagen, type Iα2 (Col1α2), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase 1 (TIMP-1)), showed some decreasing trends by the SH-Man-HSA administration. These findings suggest that the repeated administration of the Kupffer cell-targeting nanoantioxidant, SH-Man-HSA, ameliorates liver fibrosis in mice by suppressing the level of oxidative stress and a portion of the inflammation, and has a potential therapeutic effect against NASH and ASH.
Abstract
The molecular mechanism for acute kidney injury (AKI) and its progression to chronic kidney disease (CKD) continues to be unclear. In this study, we investigated the pathophysiological role ...of the acute phase protein α
1
-acid glycoprotein (AGP) in AKI and its progression to CKD using AGP KO mice. Plasma AGP levels in WT mice were increased by about 3.5-fold on day 1–2 after renal ischemia–reperfusion (IR), and these values then gradually decreased to the level before renal IR on day 7–14. On day 1 after renal IR, the AGP KO showed higher renal dysfunction, tubular injury and renal inflammation as compared with WT. On day 14, renal function, tubular injury and renal inflammation in WT had recovered, but the recovery was delayed, and renal fibrosis continued to progress in AGP KO. These results obtained from AGP KO were rescued by the administration of human-derived AGP (hAGP) simultaneously with renal IR. In vitro experiments using RAW264.7 cells showed hAGP treatment suppressed the LPS-induced macrophage inflammatory response. These data suggest that endogenously induced AGP in early renal IR functions as a renoprotective molecule via its anti-inflammatory action. Thus, AGP represents a potential target molecule for therapeutic development in AKI and its progression CKD.
The mechanism responsible for the decreased extra-renal CYP3A activity in chronic kidney disease (CKD) patients remains unknown. Using an animal model, we previously found that elevated levels of ...serum intact parathyroid hormone (iPTH) caused a reduced CYP3A activity. This retrospective observational study assessed the relationship between serum iPTH levels and the blood concentration or dosage of tacrolimus, a CYP3A substrate, after oral administration in kidney transplant patients. Thirty-four patients were enrolled who had kidney transplants between April 2014 and March 2016 and who had been administrated once- daily prolonged-release tacrolimus (Graceptor®, Astellas Pharm Inc.). Among the 34 patients, 22 had taken a CYP3A inhibitor. These patients were excluded from the study. A significant positive correlation between serum iPTH and tacrolimus trough levels was found at 4 d before kidney transplantation in 12 patients who were not receiving potent CYP3A inhibitor. In addition, serum iPTH levels before transplantation could serve as a factor for the dose of tacrolimus up to 1 year after transplantation. Monitoring serum iPTH levels could predict the trough level for the initial administration of tacrolimus, and may serve as an index for the initial dose of tacrolimus in kidney transplantation patients.
Despite the fact that liver fibrosis is an intractable disease with a poor prognosis, effective therapeutic agents are not available. In this study, we focused on bone morphogenetic factor 7 (BMP7) ...that inhibits transforming growth factor (TGF)-β signaling, which is involved in liver fibrosis. We prepared an albumin-fused BMP7 (HSA-BMP7) that is retained in the blood and evaluated its inhibitory effect on liver fibrosis. Bile duct ligated mice were used as an acute liver fibrosis model, and carbon tetrachloride-induced liver fibrosis mice were used as a chronic model. All mice were administered HSA-BMP7 once per week. In the mice with bile duct ligation, the administration of HSA-BMP7 significantly suppressed the infiltration of inflammatory cells, the area of fibrosis around the bile duct, and decreased in the level of hydroxyproline as compared with saline administration. The mRNA expression of TGF-β and its downstream fibrosis-associated genes (α-SMA and Col1a2) were also suppressed by the administration of HSA-BMP7. In the carbon tetrachloride-induced liver fibrosis mice, the HSA-BMP7 administration significantly decreased the hepatic fibrosis area and the level of hydroxyproline. Based on these results, it appears that HSA-BMP7 has the potential for serving as a therapeutic agent for the treatment of liver fibrosis.
Mannose receptors that are expressed on macrophages and fibroblasts in cancer stroma are promising therapeutic targets for cancer treatment. Albumin can be used as a drug carrier in chemotherapeutics ...due to its accumulation in the tumor tissue by the enhanced permeability and retention effects. A mannosylated albumin was recently developed as a new drug carrier targeting cells that express mannose receptors such as macrophages and fibroblasts in cancer stroma. The mannosylated albumin is specifically distributed to hepatic macrophages in vivo, leading to an extremely short residence time in the blood. Here, a dual‐modified albumin, i.e., mannosylated and polyethylene glycosylated (PEGylated) is reported, to improve its blood circulating time and stromal cell targeting. The product efficiently delivers paclitaxel to stromal cells in a mouse melanoma model, thus resulting in the disruption of stromal cells and suppressed tumor growth, which is seven times stronger than that for PEGylated albumin. The findings suggest that the dual‐modified albumin has the potential to provide maximal therapeutic efficacies of chemotherapeutics for the treatment of intractable cancer.
A dual‐modified albumin is reported, i.e., mannosylated and polyethylene glycosylated, to improve its blood circulating time and stromal cell targeting. The product efficiently delivers paclitaxel to stromal cells in a mouse melanoma model, thus resulting in the disruption of stromal cells and suppressed tumor growth. The findings suggest that the dual‐modified albumin has the potential to provide maximal therapeutic efficacies of chemotherapeutics for the treatment of intractable cancer.
Renal fibrosis is a major factor in the progression of chronic kidney disease and the final common pathway of kidney injury. Therefore, the effective therapies against renal fibrosis are urgently ...needed. The objective of this study was to investigate the effect of Am80, a synthetic retinoic acid receptor (RAR) agonist, in the treatment of renal interstitial fibrosis using unilateral ureteral obstruction (UUO) mice. The findings indicate that Am80 treatment suppressed renal fibrosis and inflammation to the same degree as the naturally-occuring retinoic acid, all-trans retinoic acid (atRA). But the adverse effect of body weight loss in Am80-treated mice was lower compared to the atRA treatment. The hepatic mRNA levels of alpha-1-acid glycoprotein (AGP), a downstream molecule of RAR agonist, was increased following administration of Am80 to healthy mice. In addition, increased AGP mRNA expression was also observed in HepG2 cells and THP-1-derived macrophages that had been treated with Am80. AGP-knockout mice exacerbated renal fibrosis, inflammation and macrophage infiltration in UUO mice, indicating endogenous AGP played an anti-fibrotic and anti-inflammatory role during the development of renal fibrosis. We also found that no anti-fibrotic effect of Am80 was observed in UUO-treated AGP-knockout mice whereas atRA treatment tended to show a partial anti-fibrotic effect. These collective findings suggest that Am80 protects against renal fibrosis via being involved in AGP function.
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