Evaluation of Keishi-bukuryo-gan in a diabetic nephropathy model by comparison with aminoguanidine, butylated hydroxytoluene and captopril

桂枝茯苓丸の糖尿病性腎症に対する作用を,モデルラットを用い検討した。腎機能パラメーター,病理組織学的検討に加え,advanced glycation end products(AGEs)の蓄積,酸化ストレスに及ぼす影響を,アミノグアニジン(AGEs阻害薬),カプトプリル(アンジオテンシン変換酵素阻害薬),buthylated hydroxytoluene(BHT)(抗酸化剤)とで比較検討した。桂枝茯苓丸では腎機能(血清Cr,尿蛋白排泄量)と病理所見の有意な改善作用が認められ,糖尿病性腎症の進展を抑制することが実験的に明らかとなったが,このような腎保護作用はカプトプリルよりは弱く,アミノグアニジンと同程度であった。BHTには腎保護作用は認められなかった。腎組織中のAGEsの蓄積に対しては,桂枝茯苓丸,カプトプリル,BHTがいずれも有意に低下していたが,アミノグアニジンの作用よりは弱かった。腎組織中の脂質過酸化量はBHTで最も低下し,桂枝茯苓丸,カプトプリルでも有意に低下していた。一方,血中脂質過酸化に対しては,すべてにおいて有意な低下作用が認められたが,カプトプリルで最も強かった。このことから,桂枝茯苓丸はカプトプリルやアミノグアニジンとは異なった機序で糖尿病性腎症の進展を抑制している可能性が示された。 A study was done to investigate whether Keishi-bukuryo-gan can delay the progression of diabetic nephropathy in an experimentally induced diabetic nephropathy model. The efficacy of Keishi-bukuryo-gan against renal functional and structural changes and its influence on accumulation of advanced glycation end-products (AGEs) and oxidative stress were also examined by comparison with aminoguanidine (an AGEs inhibitor), butylated hydroxytoluene (BHT; an antioxidant) and captopril (an angiotensin converting enzyme inhibitor). Treatment with Keishi-bukuryo-gan for 10 weeks preserved renal function, as assessed in terms of proteinuria and serum creatinine, and prevented the morphological changes peculiar to diabetic nephropathy. However, its renoprotective activity was inferior to that of captopril and comparable to that of aminoguanidine. BHT lacked any of these effects. On the other hand, renal AGEs accumulation and oxidative stress were significantly enhanced in rats with untreated diabetic nephropathy compared with normal rats. Keishi-bukuryo-gan, captopril and BHT showed significant reduction of AGEs levels, but not to the extent shown by aminoguanidine. Renal lipid peroxidation levels were significantly lowered in the groups given Keishi-bukuryo-gan and captopril, but not to the extent shown in the rats given BHT. The reduction of serum lipid peroxidation levels by captopril was stronger than that by BHT. The effects of Keishi-bukuryo-gan and aminoguanidine on serum lipid peroxidation levels were similar to those of BHT. These results suggest that the pharmaceutical characteristics of Keishi-bukuryo-gan may differ from those of the other three medicines examined

NK cells control tumor-promoting function of neutrophils in mice

Although NK cells are recognized as direct antitumor effectors, the ability of NK cells to control cancer-associated inflammation, which facilitates tumor progression, remains unknown. In this study, we demonstrate that NK cells control tumor-promoting inflammation through functional modification of neutrophils. NK cells control the tumor-promoting function of neutrophils through an IFNgamma-dependent mechanism. Tumor progression in an NK cell-depleted host is diminished when the IL17A-neutrophil axis is absent. In NK cell-depleted mice, neutrophils acquire a tumor-promoting phenotype, characterized by up-regulation of VEGF-A expression, which promotes tumor growth and angiogenesis. A VEGFR inhibitor which preferentially suppressed tumor growth in NK cell-depleted mice was dependent on neutrophils. Furthermore, the systemic neutropenia caused by an anti-metabolite treatment showed an anti-cancer effect only in mice lacking NK cells. Thus, NK cells likely control the tumor-promoting and angiogenic function of neutrophils

Different PDGF Receptor Dimers Drive Distinct Migration Modes of the Mouse Skin Fibroblast

Background/Aims: The migration of mesenchymal cells is a fundamental cellular process that has been implicated in many pathophysiological conditions and is induced by chemoattractants such as platelet-derived growth factors (PDGFs). However, the regulatory mechanisms shaping this migration remain to be elucidated. Methods: Here, we prepared mouse skin fibroblasts inactivated for different PDGF receptor genes and systematically measured their chemotactic responses within a gradient of different chemoattractants. Results: We found that PDGFRαβ and PDGFRββ dimers were strong inducers of random and directionally-persistent migration, respectively, that was sustained for up to 24 h. MAPK and PI3K were necessary to mediate random and directional migration, respectively. Directional migration was accompanied by abundant ventral stress fiber formation and consistent cell shape with less frequent formation of branch-like processes. Conclusion: This is the first systematic study that characterized the chemotaxis mediated by three-different types of PDGFR dimers in mesenchymal cell migration. Our data demonstrate that PDGFR dimer formation is the critical step to determine the specific mode of fibroblast chemotaxis, while the accompanying cytoskeletal remodeling might contribute to migration persistence

Cognitive and Socio-Emotional Deficits in Platelet-Derived Growth Factor Receptor-β Gene Knockout Mice

Platelet-derived growth factor (PDGF) is a potent mitogen. Extensive in vivo studies of PDGF and its receptor (PDGFR) genes have reported that PDGF plays an important role in embryogenesis and development of the central nervous system (CNS). Furthermore, PDGF and the β subunit of the PDGF receptor (PDGFR-β) have been reported to be associated with schizophrenia and autism. However, no study has reported on the effects of PDGF deletion on mice behavior. Here we generated novel mutant mice (PDGFR-β KO) in which PDGFR-β was conditionally deleted in CNS neurons using the Cre/loxP system. Mice without the Cre transgene but with floxed PDGFR-β were used as controls. Both groups of mice reached adulthood without any apparent anatomical defects. These mice were further examined by conducting several behavioral tests for spatial memory, social interaction, conditioning, prepulse inhibition, and forced swimming. The test results indicated that the PDGFR-β KO mice show deficits in all of these areas. Furthermore, an immunohistochemical study of the PDGFR-β KO mice brain indicated that the number of parvalbumin (calcium-binding protein)-positive (i.e., putatively γ-aminobutyric acid-ergic) neurons was low in the amygdala, hippocampus, and medial prefrontal cortex. Neurophysiological studies indicated that sensory-evoked gamma oscillation was low in the PDGFR-β KO mice, consistent with the observed reduction in the number of parvalbumin-positive neurons. These results suggest that PDGFR-β plays an important role in cognitive and socioemotional functions, and that deficits in this receptor may partly underlie the cognitive and socioemotional deficits observed in schizophrenic and autistic patients

CD206+ M2-like macrophages regulate systemic glucose metabolism by inhibiting proliferation of adipocyte progenitors

Adipose tissue resident macrophages have important roles in the maintenance of tissue homeostasis and regulate insulin sensitivity for example by secreting pro-inflammatory or anti-inflammatory cytokines. Here, we show that M2-like macrophages in adipose tissue regulate systemic glucose homeostasis by inhibiting adipocyte progenitor proliferation via the CD206/TGFβ signaling pathway. We show that adipose tissue CD206+ cells are primarily M2-like macrophages, and ablation of CD206+ M2-like macrophages improves systemic insulin sensitivity, which was associated with an increased number of smaller adipocytes. Mice genetically engineered to have reduced numbers of CD206+ M2-like macrophages show a down-regulation of TGFβ signaling in adipose tissue, together with up-regulated proliferation and differentiation of adipocyte progenitors. Our findings indicate that CD206+ M2-like macrophages in adipose tissues create a microenvironment that inhibits growth and differentiation of adipocyte progenitors and, thereby, control adiposity and systemic insulin sensitivity