Glial fibrillary acidic protein (GFAP) is a novel biomarker for the prediction of autoimmune diabetes.

Glial fibrillary acidic protein (GFAP) is expressed in peri-islet Schwann cells, as well as in glia cells, and has been reported to be an autoantigen candidate for type 1 diabetes mellitus (T1DM). We confirmed that the production of the autoantibodies GFAP and glutamic acid decarboxylase 65 (GAD65) was increased and inversely correlated with the concentration of secreted C peptide in female nonobese diabetic mice (T1DM model). Importantly, the development of T1DM in female nonobese diabetic mice at 30 wk of age was predicted by the positive GFAP autoantibody titer at 17 wk. The production of GFAP and GAD65 autoantibodies was also increased in KK-Ay mice [type 2 diabetes mellitus (T2DM) model]. In patients with diabetes mellitus, GFAP autoantibody levels were increased in patients with either T1DM or T2DM, and were significantly associated with GAD65 autoantibodies but not zinc transporter 8 autoantibodies. Furthermore, we identified a B-cell epitope of GFAP corresponding to the GFAP autoantibody in both mice and patients with diabetes. Thus, these results indicate that autoantibodies against GFAP could serve as a predictive marker for the development of overt autoimmune diabetes.-Pang, Z., Kushiyama, A., Sun, J., Kikuchi, T., Yamazaki, H., Iwamoto, Y., Koriyama, H., Yoshida, S., Shimamura, M., Higuchi, M., Kawano, T., Takami, Y., Rakugi, H., Morishita, R., Nakagumi, H. Glial fibrillary acidic protein (GFAP) is a novel biomarker for the prediction of autoimmune diabetes.

Angiotensin II Peptide Vaccine Protects Ischemic Brain Through Reducing Oxidative Stress.

BACKGROUND AND PURPOSE: Medication nonadherence is one of major risk factors for the poor outcome in ischemic stroke. Vaccination is expected to solve such a problem because of its long-lasting effects, but its effect on ischemic brain damage is still unknown. Here, we focused on vaccination for renin-angiotensin system and examined the effects of angiotensin II (Ang II) peptide vaccine in permanent middle cerebral artery occlusion model in rats. METHODS: Male Wistar rats were exposed to permanent middle cerebral artery occlusion after 3× injections of Ang II peptide vaccine, and the serum or brain level of anti-Ang II antibody was examined. The effects of the vaccine were evaluated by differences in infarction volume, brain renin-angiotensin system components, and markers for neurodegeneration and oxidative stress. RESULTS: Ang II vaccination successfully produced anti-Ang II antibodies in serum without concomitant change in blood pressure. Sufficient production of serum anti-Ang II antibody led to reduction of infarct volume and induced the penetration of anti-Ang II antibody in ischemic hemisphere, with suppressed expression of Ang II type 1 receptor mRNA. Vaccinated rats with sufficient antibody production showed the reduction of Fluoro-Jade B-positive cells, spectrin fragmentation, 4-hydroxynonenal-positive cells, and Nox 2 mRNA expression. CONCLUSIONS: Our findings indicate that Ang II vaccination exerts neuroprotective and antioxidative effects in cerebral ischemia, with renin-angiotensin system blockade by penetration of anti-Ang II antibodies into ischemic brain lesion. Ang II peptide vaccination could be a promising approach to treat ischemic stroke.

OPG/RANKL/RANK axis is a critical inflammatory signaling system in ischemic brain in mice.

Osteoprotegerin (OPG) is a soluble secreted protein and a decoy receptor, which inhibits a receptor activator of nuclear factor κB (NF-κB) ligand (RANKL)/the receptor activator of NF-κB (RANK) signaling. Recent clinical studies have shown that a high-serum-OPG level is associated with unfavorable outcome in ischemic stroke, but it is unclear whether OPG is a culprit or an innocent bystander. Here we demonstrate that enhanced RANKL/RANK signaling in OPG(-/-) mice or recombinant RANKL-treated mice contributed to the reduction of infarct volume and brain edema via reduced postischemic inflammation. On the contrary, infarct volume was increased by reduced RANKL/RANK signaling in OPG(-/-) mice and WT mice treated with anti-RANKL neutralizing antibody. OPG, RANKL, and RANK mRNA were increased in the acute stage and were expressed in activated microglia and macrophages. Although enhanced RANKL/RANK signaling had no effects in glutamate, CoCl2, or H2O2-stimulated neuronal culture, enhanced RANKL/RANK signaling showed neuroprotective effects with reduced expression in inflammatory cytokines in LPS-stimulated neuron-glia mixed culture, suggesting that RANKL/RANK signaling can attenuate inflammation through a Toll-like receptor signaling pathway in microglia. Our findings propose that increased OPG could be a causal factor of reducing RANKL/RANK signaling and increasing postischemic inflammation. Thus, the OPG/RANKL/RANK axis plays critical roles in controlling inflammation in ischemic brains.

Therapeutic vaccine against DPP4 improves glucose metabolism in mice.

The increasing prevalence of type 2 diabetes mellitus is associated with a significant economic burden. We developed a dipeptidyl peptidase 4 (DPP4)-targeted immune therapy to increase glucagon-like peptide 1 hormone levels and improve insulin sensitivity for the prevention and treatment of type 2 diabetes mellitus. Immunization with the DPP4 vaccine in C57BL/6J mice successfully increased DPP4 titer, inhibited plasma DPP4 activity, and induced an increase in the plasma glucagon-like peptide 1 level. Moreover, this elevated titer was sustained for 3 mo. In mice fed a high-fat diet, DPP4 vaccination resulted in improved postprandial glucose excursions and insulin sensitivity and, in the diabetic KK-A(y) and db/db mice strains, DPP4 vaccination significantly reduced glucose excursions and increased both plasma insulin and pancreatic insulin content. Importantly, T cells were not activated following challenge with DPP4 itself, which suggests that this vaccine does not induce cell-mediated autoimmunity. Additionally, no significant immune-mediated damage was detected in cells and tissues where DPP4 is expressed. Thus, this DPP4 vaccine may provide a therapeutic alternative for patients with diabetes.

Cross-talk of receptor activator of nuclear factor-κB ligand signaling with renin-angiotensin system in vascular calcification.

OBJECTIVE: Vascular calcification is accelerated by hypertension and also contributes to hypertension; however, it is an enigma why hypertension and vascular calcification are a vicious spiral. The present study elucidates the cross-talk between renin-angiotensin II system and receptor activator of nuclear factor-κB ligand (RANKL) system in vascular calcification. APPROACH AND RESULTS: Angiotensin (Ang) II (10(-7) mol/L) significantly increased calcium deposition as assessed by Alizarin Red staining, associated with a significant increase in the expression of RANKL, RANK, and bone-related genes, such as cbfa1 and msx2, in human aortic vascular smooth muscle cells. Infusion of Ang II (100 ng/kg per minute) in ovariectomized ApoE(-/-) mice under high-fat diet significantly increased the expression of RANKL system and calcification in vivo, whereas administration of Ang II receptor blocker (olmesartan, 3 mg/kg per day) decreased the calcification and bone markers' expression. In addition, male OPG(-/-) mice showed a significant increase in vascular calcification followed by Ang II infusion as compared with wild type. Conversely, RANKL significantly increased Ang II type 1 receptor and angiotensin II-converting enzyme expression in vascular smooth muscle cells via extracellular signal-regulated protein kinase phosphorylation. CONCLUSIONS: The present study demonstrated that Ang II significantly induced vascular calcification in vitro and in vivo through RANKL activation. In addition, RANKL activated renin-angiotensin II system, especially angiotensin II-converting enzyme and Ang II type 1 receptor. Cross-talk between renin-angiotensin II system and RANKL system might work as a vicious cycle to promote vascular calcification in atherosclerosis. Further studies to inhibit renin-angiotensin II system and RANKL may provide new therapeutic options to prevent and regress vascular calcification.

Therapeutic vaccines for hypertension and dyslipidemia.

Vaccines are commonly used as a preventive medicine for infectious diseases worldwide, however, clinical trials on an amyloid beta vaccine for Alzheimer's disease represents a new concept in the field of vaccinations. Several recent studies indicate the potential of therapeutic vaccines as well as classical vaccines as preventive medicines. A number of therapeutic vaccines for cancer have been developed as novel immunotherapies. Their targets are usually specific antigens in cancer cells, allowing activated cytotoxic T cells (CTLs) to attach and remove the antigen-presenting cancer cells. Recently, we and others have attempted to develop a therapeutic vaccine against hypertension. The vaccine target is angiotensin II (AngII), and induced anti-AngII antibodies could efficiently ameliorate high blood pressure. However, because AngII is an endogenous hormone, we must avoid the induction of autoimmune diseases by administration of an AngII vaccine. Therefore, our system was used to design a therapeutic vaccine that elicits anti-AngII antibodies without CTL activation against AngII. Because the target antigen itself does not include T cell epitopes, the immunogenic molecule (ie, KLH) provides antigen that supports the activation of T cells. In particular, helper T cells may activate B cells that produce antibodies against our specific antigen. In this review, we will explain our concept of therapeutic vaccines based on our recent data.

HIG1, a novel regulator of mitochondrial γ-secretase, maintains normal mitochondrial function.

The γ-secretase complex (which contains presenilins, nicastrin, anterior pharynx defective-1, and presenilin enhancer-2) cleaves type I transmembrane proteins, including Notch and amyloid precursor protein. Dysregulated γ-secretase activity has been implicated in the pathogenesis of Alzheimer's disease, stroke, atherosclerosis, and cancer. Tight regulation of γ-secretase activity is required for normal physiology. Here, we isolated HIG1 (hypoxia inducible gene 1, domain member 1A) from a functional screen of γ-secretase inhibitory genes. HIG1 was highly expressed in the brain. Interestingly, HIG1 was localized to the mitochondria and was directly bound to γ-secretase components on the mitochondrial membrane in SK-N-SH neuroblastoma cells. Overexpresssion of HIG1 attenuated hypoxia-induced γ-secretase activation on the mitochondrial membrane and the accumulation of intracellular amyloid ß. This accumulation was accompanied by hypoxia-induced mitochondrial dysfunction. The latter half domain of HIG1 was required for binding to the γ-secretase complex and suppression of γ-secretase activity. Moreover, depletion of HIG1 increased γ-secretase activation and enhanced hypoxia-induced mitochondrial dysfunction. In summary, HIG1 is a novel modulator of the mitochondrial γ-secretase complex, and may play a role in the maintenance of normal mitochondrial function.

Estrogen inhibits vascular calcification via vascular RANKL system: common mechanism of osteoporosis and vascular calcification.

RATIONALE: Arterial calcification and osteoporosis are associated in postmenopausal women. RANK (the receptor activator of nuclear factor kappaB), RANKL (RANK ligand), and osteoprotegerin are key proteins in bone metabolism and have been found at the site of aortic calcification. The role of these proteins in vasculature, as well as the contribution of estrogen to vascular calcification, is poorly understood. OBJECTIVE: To clarify the mechanism of RANKL system to vascular calcification in the context of estrogen deficiency. METHODS AND RESULTS: RANKL induced the calcification inducer bone morphogenetic protein-2 by human aortic endothelial cells (HAECs) and decreased the calcification inhibitor matrix Gla protein (MGP) in human aortic smooth muscle cells (HASMCs), as quantified by real-time PCR and Western blot analysis. RANKL also induced bone-related gene mRNA expression and calcium deposition (Alizarin red staining) followed by the osteogenic differentiation of HASMCs. Estrogen inhibited RANKL signaling in HAECs and HASMCs mainly through estrogen receptor alpha. Apolipoprotein E-deficient mice fed with Western high-fat diet for 3 months presented atherosclerotic calcification (Oil red and Alizarin red staining) and osteoporosis (microcomputed tomographic analysis) after ovariectomy and increased expression of RANKL, RANK, and osteopontin in atherosclerotic lesion, as detected by in situ hybridization. Estrogen replacement inhibited osteoporosis and the bone morphogenetic protein osteogenic pathway in aorta by decreasing phosphorylation of smad-1/5/8 and increasing MGP mRNA expression. CONCLUSIONS: RANKL contributes to vascular calcification by regulating bone morphogenetic protein-2 and MGP expression, as well as bone-related proteins, and is counteracted by estrogen in a receptor-dependent manner.

FHL-2 suppresses VEGF-induced phosphatidylinositol 3-kinase/Akt activation via interaction with sphingosine kinase-1.

OBJECTIVE: In the functional screening of a human heart cDNA library to identify a novel antiangiogenic factor, the prime candidate gene was "four-and-a-half LIM only protein-2" (FHL-2). The goal of this study is to clear the mechanism of antiangiogenic signaling of FHL-2 in endothelial cells (ECs). METHODS AND RESULTS: Overexpressed FHL-2 strongly inhibited vascular endothelial growth factor (VEGF)-induced EC migration. In the angiogenic signaling, we focused on sphingosine kinase-1 (SK1), which produces sphingosine-1-phosphate (S1P), a bioactive sphingolipid, as a potent angiogenic mediator in ECs. Immunoprecipitation and immunostaining analysis showed that FHL-2 might bind to SK1. Importantly, overexpression of FHL-2 in ECs inhibited VEGF-induced SK1 activity, phosphatidylinositol 3-kinase activity, and phosphorylation of Akt and eNOS. In contrast, overexpression of FHL-2 had no effect on S1P-induced Akt phosphorylation. Interestingly, VEGF stimulation decreased the binding of FHL-2 and SK1. Depletion of FHL-2 by siRNA increased EC migration accompanied with SK1 and Akt activation, and increased the expression of VEGF receptor-2 which further enhanced VEGF signaling. Furthermore, injection of FHL-2 mRNA into Xenopus embryos resulted in inhibition of vascular network development, assessed by in situ hybridization with endothelial markers. CONCLUSIONS: FHL-2 may regulate phosphatidylinositol 3-kinase/Akt via direct suppression of the SK1-S1P pathway in ECs.

Development of an IL-17A DNA Vaccine to Treat Systemic Lupus Erythematosus in Mice.

The interleukin-17 (IL-17) family, especially IL-17A, plays an important role in the pathogenesis of systemic lupus erythematosus (SLE). This study developed an IL-17A epitope vaccine to treat SLE in NZBWF1 and MRL/lpr mouse models. A plasmid vector encoding a hepatitis B core (HBc)-IL-17A epitope fusion protein was injected using electroporation into the skeletal muscle of NZBWF1(New Zealand Black mice x New Zealand White mice F1 hybrid strain) or MRL/lpr mice three times at 2-week intervals. As a result, anti-IL-17A antibodies were successfully produced in the HBc-IL-17A group. Accordingly, serum tumor necrosis factor alpha (TNF-α) concentrations were significantly reduced in the HBc-IL-17A group. According to pathological analysis, the IL-17A DNA vaccine significantly suppressed renal tissue damage and macrophage infiltration. Consequently, the survival rate was significantly improved in the HBc-IL-17A group. In addition, we evaluated the antigen reactivity of splenocytes from IL-17A-immunized mice using an enzyme-linked immune absorbent spot (ELISPot) assay for safety evaluation. Splenocytes from IL-17A-immunized mice were significantly stimulated by the HBc epitope peptide, but not by the IL-17A epitope or recombinant IL-17A. These results indicate that the IL-17A vaccine did not induce autoreactive T cells against endogenous IL-17A. This study demonstrates for the first time that an IL-17A DNA vaccine significantly reduced organ damage and extended survival time in lupus-prone mice.

AJP001, a novel helper T-cell epitope, induces a humoral immune response with activation of innate immunity when included in a peptide vaccine.

Vaccine design requires well-tailored formulations including a T-cell epitope and adjuvants. We identified a novel cationic peptide, AJP001, which possesses a strong affinity for murine MHC class II alleles (H2-IEd and H2-IAd) and low affinity for H2-IAb. We designed an AJP001 and epitope peptide-conjugated vaccine, AJP001-angiotensin (Ang) II, which was intracutaneously administered to mice three times at 2-week intervals. Indeed, the AJP001-Ang II vaccine induced antibody production against Ang II in BALB/cA mice but not in C57BL/6 mice. To estimate the T-cell-dependent immunogenicity of the AJP001 conjugate vaccine in human cells, naïve human peripheral blood mononuclear cells (PBMCs) were exposed to AJP001-Ang II, and T-cell proliferation was evaluated by analyzing cell division using flow cytometric measurement of carboxyfluorescein succinimidyl ester (CFSE) dye dilution. To activate the immune response, the innate immune system must be activated by adjuvant treatment. Interestingly, treatment with AJP001 induced IL-1ß and IL-18 secretion via NLRP3 inflammasome activation and induced TNF-α and IL-6 production through an NF-κB-dependent pathway in human and mouse macrophages. These results suggest that AJP001 behaves as a T-cell epitope in mice and humans and is a useful tool for the formulation of peptide vaccines without the addition of adjuvants.

Therapeutic Vaccine Against S100A9 (S100 Calcium-Binding Protein A9) Inhibits Thrombosis Without Increasing the Risk of Bleeding in Ischemic Stroke in Mice.

Decreased adherence to daily ingestion of antiplatelet drugs is a critical issue, increasing mortality and morbidity in poststroke patients. As vaccination could be a promising approach to solving this, we designed an antiplatelet vaccine that inhibited S100A9 (S100 calcium-binding protein A9)/CD36 (cluster of differentiation 36) signaling in platelets, which was reported to be a key signal in arterial thrombosis, but not hemostasis. Immunization with this vaccine induced a sustainable increase in the anti-S100A9 antibody titer for >2 months and an additional booster immunization enhanced the antibody production further. The middle cerebral artery occlusion time was successfully prolonged in the vaccinated mice, which was comparable to that in mice treated with clopidogrel. The antithrombotic effect lasted for 84 days after the last vaccination, as well as after the booster immunization. Importantly, the bleeding time was not affected in the immunized mice. The antithrombotic effect was also observed in the common carotid artery, which was similar to that found in CD36-/- mice. Vascular injury increased the expression of S100A9 in the serum and phosphorylation of JNK (c-Jun N-terminal kinase) and VAV1 in the platelets, but these increases were inhibited in the immunized mice. Moreover, the S100A9 vaccine did not induce cell-mediated autoimmunity, as demonstrated by the enzyme-linked immunosorbent spot assay. Thus, immunization with the S100A9 vaccine resulted in long-term inhibition of thrombus formation through inhibition of increased S100A9/CD36 signaling without risk of bleeding or adverse autoimmune responses. Vaccination against S100A9 might be a novel therapy to prevent recurrent ischemic stroke.

Evaluating the potential of the GFAP-KLH immune-tolerizing vaccine for type 1 diabetes in mice.

Glial fibrillary acidic protein (GFAP), expressed in peri-islet Schwann cells, is a novel target for the treatment of type 1 diabetes mellitus (T1DM). We designed a GFAP immune-tolerizing vaccine that successfully suppresses hyperglycemia and enhances C peptide secretion. The GFAP vaccine significantly prevented T cell infiltration into pancreatic islets. Moreover, after GFAP vaccination, naïve T-cell differentiation shifted from a cytotoxic Th1- to a Th2-biased humoral response. These results indicate that as a novel target, GFAP reliably predicts the development of T1DM, and that the GFAP vaccine successfully delays the progression of T1DM by regulating T-cell differentiation.

A peptide vaccine targeting angiotensin II attenuates the cardiac dysfunction induced by myocardial infarction.

A peptide vaccine targeting angiotensin II (Ang II) was recently developed as a novel treatment for hypertension to resolve the problem of noncompliance with pharmacotherapy. Ang II plays a crucial role in the pathogenesis of cardiac remodeling after myocardial infarction (MI), which causes heart failure. In the present study, we examined whether the Ang II vaccine is effective in preventing heart failure. The injection of the Ang II vaccine in a rat model of MI attenuated cardiac dysfunction in association with an elevation in the serum anti-Ang II antibody titer. Furthermore, any detrimental effects of the Ang II vaccine were not observed in the rats that underwent sham operations. Treatment with immunized serum from Ang II vaccine-injected rats significantly suppressed post-MI cardiac dysfunction in MI rats and Ang II-induced remodeling-associated signaling in cardiac fibroblasts. Thus, our present study demonstrates that the Ang II vaccine may provide a promising novel therapeutic strategy for preventing heart failure.

A Novel Therapeutic Peptide as a Partial Agonist of RANKL in Ischemic Stroke.

The enhanced receptor activator of nuclear factor-κB (NFκB) ligand (RANKL) and its receptor (RANK) signal have been reported to attenuate ischemic brain injury through inhibition of Toll-like receptor (TLR) 4-mediated inflammation. However, augmentation of the RANKL/RANK signal also accelerates osteoporosis, which is a potential problem in clinical use of RANKL. Therefore, we developed novel peptides, microglial healing peptides (MHPs), which were based on the DE and/or EF loop of RANKL. Among them, MHP1 was the most effective inhibitor of TLR4-induced inflammations in microglia/macrophages. The effects depended on RANK, as confirmed by knockdown experiments. In contrast to RANKL, MHP1 did not stimulate osteoclast differentiation. Unexpectedly, MHP1 inhibited RANKL-induced osteoclast differentiation. These findings suggested that MHP1 was a partial agonist of RANKL, and administration of MHP1 attenuated ischemic injury by decreasing inflammation. MHP1 could be a novel therapeutic agent for treating ischemic stroke.

Long-Term Reduction of High Blood Pressure by Angiotensin II DNA Vaccine in Spontaneously Hypertensive Rats.

Recent research on vaccination has extended its scope from infectious diseases to chronic diseases, including Alzheimer disease, dyslipidemia, and hypertension. The aim of this study was to design DNA vaccines for high blood pressure and eventually develop human vaccine therapy to treat hypertension. Plasmid vector encoding hepatitis B core-angiotensin II (Ang II) fusion protein was injected into spontaneously hypertensive rats using needleless injection system. Anti-Ang II antibody was successfully produced in hepatitis B core-Ang II group, and antibody response against Ang II was sustained for at least 6 months. Systolic blood pressure was consistently lower in hepatitis B core-Ang II group after immunization, whereas blood pressure reduction was continued for at least 6 months. Perivascular fibrosis in heart tissue was also significantly decreased in hepatitis B core-Ang II group. Survival rate was significantly improved in hepatitis B core-Ang II group. This study demonstrated that Ang II DNA vaccine to spontaneously hypertensive rats significantly lowered high blood pressure for at least 6 months. In addition, Ang II DNA vaccines induced an adequate humoral immune response while avoiding the activation of self-reactive T cells, assessed by ELISPOT assay. Future development of DNA vaccine to treat hypertension may provide a new therapeutic option to treat hypertension.

Peptide Vaccines for Hypertension and Diabetes Mellitus.

Vaccines are commonly used as a preventive medicine for infectious diseases worldwide; however, the trial for an amyloid beta vaccine against Alzheimer's disease will open a new concept in vaccination. In case of therapeutic vaccines for cancer, their targets are usually specific antigens in cancer cells, allowing activated cytotoxic T cells (CTLs) to attach and remove the antigen-presenting cancer cells. In our therapeutic vaccines against hypertension, the target is angiotensin II (Ang II) and induced anti-Ang II antibodies could efficiently ameliorate high blood pressure. Similarly, we developed the therapeutic vaccine against DPP4 for diabetes mellitus. However, because Ang II or DPP4 is an endogenous hormone, we must avoid autoimmune disease induced by these vaccines. Therefore, our system was used to design a therapeutic vaccine that elicits anti-Ang II or DPP4 antibodies without CTL activation against Ang II or DPP4. In this review, we will describe our concept of therapeutic vaccines for hypertension and diabetes mellitus.

Long-term expression of periostin during the chronic stage of ischemic stroke in mice.

Periostin is an extracellular matrix glycoprotein and has various cellular effects. Previously, we demonstrated the neuroprotective effects of periostin during the acute stage of cerebral ischemia. However, its expression during the chronic stage remains unknown. Herein, we examined the expression of full-length periostin (periostin 1; Pn1) and its splicing variant lacking exon 17 (periostin 2; Pn2) during the 28 days following transient middle cerebral artery occlusion in mice. Real-time reverse transcription-PCR showed that the expression of Pn2 was dramatically upregulated between days 3 and 28, and the highest expression was observed on day 7. The expression of Pn1 was also increased, but delayed compared with Pn2. Immunohistochemistry showed that periostin was weakly expressed in reactive astrocytes in the peri-infarct region and in microglia/macrophages in infarct regions, on days 3 and 7. Periostin was also expressed around CD31-positive cells in both the peri-infarct and the sub-ventricular zone (SVZ) on days 3 and 7. SOX-2 positive cells, which are neural stem cells, also expressed periostin on day 7. The highest periostin immunoreactivity that occurred co-localized with collagen I and fibronectin in the peri-infarct region between days 7 and 28. Thus, the expression pattern of periostin mRNA was dependent on the splicing variant, and it continued to be expressed up to 28 days after cerebral ischemia. As periostin was expressed in various cells, such as reactive astrocytes/microglia, fibroblasts and neuronal progenitor cells, periostin might be associated with pathophysiology in post-ischemic inflammation and neurogenesis.

The dipeptidyl peptidase-4 inhibitor teneligliptin improved endothelial dysfunction and insulin resistance in the SHR/NDmcr-cp rat model of metabolic syndrome.

Diabetes mellitus, hypertension and metabolic syndrome are major risk factors for the occurrence of cardiovascular events. In this study, we used spontaneous hypertensive rat (SHR)/NDmcr-cp (cp/cp) (SHRcp) rats as a model for metabolic syndrome to examine the effects of dipeptidyl peptidase (DPP)-4 inhibition on hypertension, glucose metabolism and endothelial dysfunction. First, we confirmed that SHRcp rats showed very severe obesity, hypertension and endothelial dysfunction phenotypes from 14 to 54 weeks of age. Next, we examined whether the DPP-4 inhibitor teneligliptin (10 mg kg(-1) per day per os for 12 weeks) could modify any of these phenotypes. Treatment with teneligliptin significantly improved hyperglycemia and insulin resistance, as evidenced by an oral glucose tolerance test and homeostasis model assessment for insulin resistance, respectively. Teneligliptin showed no effects on systolic blood pressure or heart rate. In regard to endothelial function, the vasodilator response to acetylcholine was significantly impaired in SHRcp rats when compared with WKY rats. Long-term treatment with teneligliptin significantly attenuated endothelial dysfunction through the upregulation of endothelium-derived nitric oxide synthase mRNA. These results demonstrate that long-term treatment with teneligliptin significantly improved endothelial dysfunction and glucose metabolism in a rat model of metabolic syndrome, suggesting that teneligliptin treatment might be beneficial for patients with hypertension and/or diabetes.

Gene therapy and cell-based therapies for therapeutic angiogenesis in peripheral artery disease.

Gene therapy and cell-based therapy have emerged as novel therapies to promote therapeutic angiogenesis in critical limb ischemia (CLI) caused by peripheral artery disease (PAD). Although researchers initially focused on gene therapy using proangiogenic factors, such as vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and hepatocyte growth factors (HGF), cell therapy using bone marrow mononuclear cells (BMMNCs), mesenchymal stem cells (BMMSCs), G-CSF-mobilized peripheral blood mononuclear cells (M-PBMNCs), and endothelial progenitor cells (EPCs) have also been extensively studied. Based on the elaborate studies and favorable results of basic research, some clinical phase I/II trials have been performed, and the results demonstrate the safety of these approaches and their potential for symptomatic improvement in CLI. However, the phase 3 clinical trials have thus far been limited to gene therapy using the HGF gene. Further studies using well-designed larger placebo-controlled and long-term randomized control trials (RCTs) will clarify the effectiveness of gene therapy and cell-based therapy for the treatment of CLI. Furthermore, the development of efficient gene transfer systems and effective methods for keeping transplanted cells healthy will make these novel therapies more effective and ease the symptoms of CLI.