scholarly journals FSP-1 Impairs the Function of Endothelium Leading to Failure of Arteriovenous Grafts in Diabetic Mice

Endocrinology ◽  
2015 ◽  
Vol 156 (6) ◽  
pp. 2200-2210 ◽  
Author(s):  
Jinlong Luo ◽  
Ming Liang ◽  
William E. Mitch ◽  
Farhad R. Danesh ◽  
Michael Yu ◽  
...  

Abstract To understand how endothelial cell (EC) dysfunction contributes to the failure of arteriovenous graft (AVG), we investigated the role of fibroblast-specific protein 1 (FSP-1) in cultured ECs and a mouse AVG model. In vitro, we uncovered a new FSP-1-dependent pathway that activates rho-associated, coiled-coil-containing protein kinase 1 (ROCK1) in ECs, leading to phosphorylation of myosin light chain 2 resulting in EC dysfunction. In cultured ECs, high glucose stimulated FSP-1 expression and increased permeability of an EC monolayer. The increase in permeability by the high glucose concentration was mediated by FSP-1 expression. Treatment of cultured ECs with FSP-1 caused leakage of the endothelial barrier plus increased expression of adhesion molecules and decreased expression of junction molecules. These responses were initiated by binding of FSP-1 to receptor for advanced glycation end products, which resulted in ROCK1 activation. In vivo, diabetes increased infiltration of inflammatory cells into AVGs and stimulated neointima formation. Increased FSP-1 expression and ROCK1 activation were found in AVGs of diabetic mice. Blocking FSP-1 suppressed diabetes-induced ROCK1 activation in AVGs. In mice with FSP-1 knockout or with ROCK1 knockout, accumulation of inflammatory cells and neointima formation in AVG were attenuated despite diabetes. Thus, mechanisms of inhibiting FSP-1 in ECs could improve AVG function.

1999 ◽  
Vol 147 (6) ◽  
pp. 1275-1286 ◽  
Author(s):  
Conrad L. Leung ◽  
Dongming Sun ◽  
Min Zheng ◽  
David R. Knowles ◽  
Ronald K.H. Liem

We cloned and characterized a full-length cDNA of mouse actin cross-linking family 7 (mACF7) by sequential rapid amplification of cDNA ends–PCR. The completed mACF7 cDNA is 17 kb and codes for a 608-kD protein. The closest relative of mACF7 is the Drosophila protein Kakapo, which shares similar architecture with mACF7. mACF7 contains a putative actin-binding domain and a plakin-like domain that are highly homologous to dystonin (BPAG1-n) at its NH2 terminus. However, unlike dystonin, mACF7 does not contain a coiled–coil rod domain; instead, the rod domain of mACF7 is made up of 23 dystrophin-like spectrin repeats. At its COOH terminus, mACF7 contains two putative EF-hand calcium-binding motifs and a segment homologous to the growth arrest–specific protein, Gas2. In this paper, we demonstrate that the NH2-terminal actin-binding domain of mACF7 is functional both in vivo and in vitro. More importantly, we found that the COOH-terminal domain of mACF7 interacts with and stabilizes microtubules. In transfected cells full-length mACF7 can associate not only with actin but also with microtubules. Hence, we suggest a modified name: MACF (microtubule actin cross-linking factor). The properties of MACF are consistent with the observation that mutations in kakapo cause disorganization of microtubules in epidermal muscle attachment cells and some sensory neurons.


2020 ◽  
Vol 11 (9) ◽  
Author(s):  
Qiongxia Deng ◽  
Ruowei Wen ◽  
Sirui Liu ◽  
Xiaoqiu Chen ◽  
Shicong Song ◽  
...  

Abstract Excessive mitochondrial fission plays a key role in podocyte injury in diabetic kidney disease (DKD), and long noncoding RNAs (lncRNAs) are important in the development and progression of DKD. However, lncRNA regulation of mitochondrial fission in podocytes is poorly understood. Here, we studied lncRNA maternally expressed gene 3 (Meg3) in mitochondrial fission in vivo and in vitro using human podocytes and Meg3 podocyte-specific knockdown mice. Expression of lncRNA Meg3 in STZ-induced diabetic mice was higher, and correlated with the number of podocytes. Excessive mitochondrial fission of podocytes and renal histopathological and physiological parameters were improved in podocyte-specific Meg3 knockdown diabetic mice. Elongated mitochondria with attenuated podocyte damage, as well as mitochondrial translocation of dynamin-related protein 1 (Drp1), were decreased in Meg3 knockout podocytes. By contrast, increased fragmented mitochondria, podocyte injury, and Drp1 expression and phosphorylation were observed in lncRNA Meg3-overexpressing podocytes. Treatment with Mdivi1 significantly blunted more fragmented mitochondria and reduced podocyte injury in lncRNA Meg3-overexpressing podocytes. Finally, fragmented mitochondria and Drp1 mitochondrial translocation induced by high glucose were reduced following treatment with Mdivi1. Our data show that expression of Meg3 in podocytes in both human cells and diabetic mice was higher, which regulates mitochondrial fission and contributes to podocyte injury through increased Drp1 and its translocation to mitochondria.


2021 ◽  
Vol 8 ◽  
Author(s):  
Qi Li ◽  
Delma Veron ◽  
Alda Tufro

The molecular pathogenesis of diabetic kidney disease progression is complex and remains unresolved. Rho-GAP MYO9A was recently identified as a novel podocyte protein and a candidate gene for monogenic FSGS. Myo9A involvement in diabetic kidney disease has been suggested. Here, we examined the effect of diabetic milieu on Myo9A expression in vivo and in vitro. We determined that Myo9A undergoes S-nitrosylation, a post-translational modification dependent on nitric oxide (NO) availability. Diabetic mice with nodular glomerulosclerosis and severe proteinuria associated with doxycycline-induced, podocyte-specific VEGF164 gain-of-function showed markedly decreased glomerular Myo9A expression and S-nitrosylation, as compared to uninduced diabetic mice. Immortalized mouse podocytes exposed to high glucose revealed decreased Myo9A expression, assessed by qPCR, immunoblot and immunocytochemistry, and reduced Myo9A S-nitrosylation (SNO-Myo9A), assessed by proximity link assay and biotin switch test, functionally resulting in abnormal podocyte migration. These defects were abrogated by exposure to a NO donor and were not due to hyperosmolarity. Our data demonstrate that high-glucose induced decrease of both Myo9A expression and SNO-Myo9A is regulated by NO availability. We detected S-nitrosylation of Myo9A interacting proteins RhoA and actin, which was also altered by high glucose and NO dependent. RhoA activity inversely related to SNO-RhoA. Collectively, data suggest that dysregulation of SNO-Myo9A, SNO-RhoA and SNO-actin may contribute to the pathogenesis of advanced diabetic kidney disease and may be amenable to therapeutic targeting.


2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Bo Zhao ◽  
Quan Yuan ◽  
Jia-bao Hou ◽  
Zhong-yuan Xia ◽  
Li-ying Zhan ◽  
...  

Background. A substantial increase in histone deacetylase 3 (HDAC3) expression is implicated in the pathological process of diabetes and stroke. However, it is unclear whether HDAC3 plays an important role in diabetes complicated with stroke. We aimed to explore the role and the potential mechanisms of HDAC3 in cerebral ischemia/reperfusion (I/R) injury in diabetic state. Methods. Diabetic mice were subjected to 1 h ischemia, followed by 24 h reperfusion. PC12 cells were exposed to high glucose for 24 h, followed by 3 h of hypoxia and 6 h of reoxygenation (H/R). Diabetic mice received RGFP966 (the specific HDAC3 inhibitor) or vehicle 30 minutes before the middle cerebral artery occlusion (MCAO), and high glucose-incubated PC12 cells were pretreated with RGFP966 or vehicle 6 h before H/R. Results. HDAC3 inhibition reduced the cerebral infarct volume, ameliorated pathological changes, improved the cell viability and cytotoxicity, alleviated apoptosis, attenuated oxidative stress, and enhanced autophagy in cerebral I/R injury model in diabetic state in vivo and in vitro. Furthermore, we found that the expression of HDAC3 was remarkably amplified, and the Bmal1 expression was notably decreased in diabetic mice with cerebral I/R, whereas this phenomenon was obviously reversed by RGFP966 pretreatment. Conclusions. These results suggested that the HDAC3 was involved in the pathological process of the complex disease of diabetic stroke. Suppression of HDAC3 exerted protective effects against cerebral I/R injury in diabetic state in vivo and in vitro via the modulation of oxidative stress, apoptosis, and autophagy, which might be mediated by the upregulation of Bmal1.


Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 608
Author(s):  
Laura Ciarlo ◽  
Francesca Marzoli ◽  
Paola Minosi ◽  
Paola Matarrese ◽  
Stefano Pieretti

Glycyrrhiza glabra, commonly known as liquorice, contains several bioactive compounds such as flavonoids, sterols, triterpene, and saponins; among which, glycyrrhizic acid, an oleanane-type saponin, is the most abundant component in liquorice root. Diabetic peripheral neuropathy is one of the major complications of diabetes mellitus, leading to painful condition as neuropathic pain. The pathogenetic mechanism of diabetic peripheral neuropathy is very complex, and its understanding could lead to a more suitable therapeutic strategy. In this work, we analyzed the effects of ammonium glycyrrhizinate, a derivate salt of glycyrrhizic acid, on an in vitro system, neuroblastoma cells line SH-SY5Y, and we observed that ammonium glycyrrhizinate was able to prevent cytotoxic effect and mitochondrial fragmentation after high-glucose administration. In an in vivo experiment, we found that a short-repeated treatment with ammonium glycyrrhizinate was able to attenuate neuropathic hyperalgesia in streptozotocin-induced diabetic mice. In conclusion, our results showed that ammonium glycyrrhizinate could ameliorate diabetic peripheral neuropathy, counteracting both in vitro and in vivo effects induced by high glucose, and might represent a complementary medicine for the clinical management of diabetic peripheral neuropathy.


2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Eva Ludvigsen ◽  
Mats Stridsberg ◽  
Eva T. Janson ◽  
Stellan Sandler

Somatostatin acts via five receptors (sst1-5). We investigated if the changes in pancreatic islet sst expression in diabetic NOD mice compared to normoglycemic mice are a consequence of hyperglycemia or the ongoing immune reaction in the pancreas. Pancreatic islets were isolated from NOD mice precultured for 5 days and further cultured for 3 days at high or low glucose before examined. Islets were also isolated from NOD mice and transplanted to normal or diabetic mice in a number not sufficient to cure hyperglycemia. After three days, the transplants were removed and stained for sst1-5and islet hormones. Overall, changes in sst islet cell expression were more common in islets cultured in high glucose concentrationin vitroas compared to the islet transplantationin vivoto diabetic mice. The beta and PP cells exhibited more frequent changes in sst expression, while the alpha and delta cells were relatively unaffected by the high glucose condition. Our findings suggest that the glucose level may alter sst expressed in islets cells; however, immune mechanisms may counteract such changes in islet sst expression.


2021 ◽  
Author(s):  
Ying Cai ◽  
Yong Xu ◽  
Qicheng Ni ◽  
Bei Guo ◽  
Sheng Chen ◽  
...  

Abstract Objective Ellagic acid (EA) as a multi-target bioactive compound has been reported to improve diabetes-related complications, including diabetic nephropathy (DN). Herein, we plan to investigate the molecular mechanism underlying EA-mediated renal protection in diabetic mice. Methods Streptozotocin (STZ; 35 mg/kg successive injection for 5 times) was applied to establish DN model in mice. Normal or diabetic mice were administrated by EA (100 mg/kg/day) by intragastric administration for 8 weeks. In vitro diabetic cell model, podocytes and renal tubular epithelial cells (RTECs) were exposed to normal glucose (NG; 5 mM) or high glucose (HG; 30 mM). Results Our results demonstrated that EA treatment prevented HG-induced podocyte and RTEC apoptosis and growth inhibition by inhibiting NF-κB/miR-150-3p to activate BCL2 in vitro. In vivo diabetic model of mice, EA administration improved renal filtration function, tubular and glomerular injury, and interstitial fibrosis. More importantly, supplementation of EA also suppressed NF-κB/miR-150-3p activation and accelerated BCL2 expression in the kidney of diabetic mice. In another experiment, miR-150-3p antagomir as a potential gene therapeutic choice has been validated to rescue hyperglycemia-induced renal dysfunction in mouse model. Taken together, in vitro and in vivo experimental measurements corroborate that EA modulates NF-κB/miR-150-3p/BCL2 cascade signaling to attenuate renal damage in diabetic models. Conclusion Our findings revealed that EA modulated the suppression of NF-κB/miR-150-3p to activate BCL2 that contributed to prevent hyperglycemia-induced renal dysfunction. In addition, synthetic miR-150-3p antagomir or inhibitors could alleviate tubular injury and interstitial fibrosis, and prevent HG-induced podocyte and RTEC apoptosis.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Spencer Brown ◽  
Francis Caputo ◽  
Marc Fromer ◽  
Ping Zhang ◽  
Shauhoa Chang ◽  
...  

Background: Diabetes type 1 and 2 cause hyperglycemia and result in endothelial dysfunction with endothelial vessel and poor wound healing. Adipose-derived stem cells (ASCs), progenitor cells in wound healing, show decreased function under hyperglycemic conditions in vitro and in vivo . We hypothesized that exposing ASCs in the presence of high glucose with the human umbilical vein endothelial cell (HUVEC) secretome will reverse the deleterious effects of glucose on ASCs and subsequently enhance angiogenesis and wound healing. Methods: Human umbilical vein endothelial cells (HUVEC) were treated with glucose (30mM) and the conditioned media (CM) were collected every 3 days. ASCs were then co-cultured with EC/CM for 2 weeks. To produce thermal denaturation of protein, EC/CM was heated at 95 0 C for 30 mins. Cell activity, proliferation, and endothelial-like properties of ASCs were determined by MTT assays, growth curves, and real-time RT-PCR, respectively. EC/CM treated ASC were injected into a normal or diabetic murine left thigh muscle at three different points with hindlimb ischemia. After 4 weeks injection, animals were sacrificed. H & E and double immunostaining for CD31 and anti-human nuclei were used to determine if the ASCs primed with EC/CM underwent neovascularization. Results: In fact, ASCs increased in proliferation when co-cultured with HUVEC/CM (1.4 fold) when compared with controls. This promoting effect was lost in heated HUVEC/CM, indicating that the active molecules are of protein origin. After 10 days stimulated with EC/CM an increase in mRNA expression levels of EC markers were also observed in high glucose (30mM) EC/CM environment including CD31 (2-fold), vWF (1.1-fold), and eNOS (3.2-fold) when compared to ASCs cultured in M199. H & E and immunohistochemical staining results showed elevated vessel density and CD31 + cell levels in HUVEC-primed ASC injection sites of diabetic mice when compared with the control animals. Conclusions: HUVEC secrete protein factors that increase proliferation and endothelial differentiation of ASCs under diabetic conditions. Injection of ischemic hindlimbs in diabetic mice with HUVEC-primed ASCs leads to improved angiogenesis.


Author(s):  
U. Aebi ◽  
L.E. Buhle ◽  
W.E. Fowler

Many important supramolecular structures such as filaments, microtubules, virus capsids and certain membrane proteins and bacterial cell walls exist as ordered polymers or two-dimensional crystalline arrays in vivo. In several instances it has been possible to induce soluble proteins to form ordered polymers or two-dimensional crystalline arrays in vitro. In both cases a combination of electron microscopy of negatively stained specimens with analog or digital image processing techniques has proven extremely useful for elucidating the molecular and supramolecular organization of the constituent proteins. However from the reconstructed stain exclusion patterns it is often difficult to identify distinct stain excluding regions with specific protein subunits. To this end it has been demonstrated that in some cases this ambiguity can be resolved by a combination of stoichiometric labeling of the ordered structures with subunit-specific antibody fragments (e.g. Fab) and image processing of the electron micrographs recorded from labeled and unlabeled structures.


2020 ◽  
Vol 18 ◽  
Author(s):  
Zirui Zhang ◽  
Shangcong Han ◽  
Panpan Liu ◽  
Xu Yang ◽  
Jing Han ◽  
...  

Background: Chronic inflammation and lack of angiogenesis are the important pathological mechanisms in deep tissue injury (DTI). Curcumin is a well-known anti-inflammatory and antioxidant agent. However, curcumin is unstable under acidic and alkaline conditions, and can be rapidly metabolized and excreted in the bile, which shortens its bioactivity and efficacy. Objective: This study aimed to prepare curcumin-loaded poly (lactic-co-glycolic acid) nanoparticles (CPNPs) and to elucidate the protective effects and underlying mechanisms of wound healing in DTI models. Methods: CPNPs were evaluated for particle size, biocompatibility, in vitro drug release and their effect on in vivo wound healing. Results : The results of in vivo wound closure analysis revealed that CPNP treatments significantly improved wound contraction rates (p<0.01) at a faster rate than other three treatment groups. H&E staining revealed that CPNP treatments resulted in complete epithelialization and thick granulation tissue formation, whereas control groups resulted in a lack of compact epithelialization and persistence of inflammatory cells within the wound sites. Quantitative real-time PCR analysis showed that treatment with CPNPs suppressed IL-6 and TNF-α mRNA expression, and up-regulated TGF-β, VEGF-A and IL-10 mRNA expression. Western blot analysis showed up-regulated protein expression of TGF-β, VEGF-A and phosphorylatedSTAT3. Conclusion: Our results showed that CPNPs enhanced wound healing in DTI models, through modulation of the JAK2/STAT3 signalling pathway and subsequent upregulation of pro-healing factors.


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