scholarly journals Daunorubicin associated to lipid core nanoparticles reduces atherosclerotic lesions, inflammation and cardiotoxicity in atherosclerosis rabbit model

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C.I Albuquerque ◽  
E.R Tavares ◽  
M.C Guido ◽  
N.M Lopes ◽  
R.V Baroni ◽  
...  
Keyword(s):  
Body Weight ◽  
Protein Expression ◽  
Post Treatment ◽  
Heart Weight ◽  
Funding Source ◽  
Lipid Core ◽  
Atherosclerotic Lesions ◽  
Apoptotic Factors ◽  
Aortic Lesions ◽  
Core Nanoparticles

Abstract Introduction Antiproliferative agents used in cancer chemotherapy have low toxicity and increased pharmacological action when carried into lipid core nanoparticles (LDE). LDE has similar structure to LDL and binds to LDL receptors through apo E it acquires in contact with plasma. Previously, we showed that treatment of rabbits with atherosclerosis with drugs such as taxanes and etoposide associate to LDE had pronounced reduction of the atherosclerotic lesions. In this study, we hypothesized whether daunorubicin (DNR) that belongs to another class of anti-cancer drugs, with a distinct mechanism of action and that has strong cardiotoxicity could also have effects against atherosclerosis. Methods Sixteen New Zealand male rabbits were fed with a 1% cholesterol diet for 8 weeks to induce atherosclerosis. After 4 weeks, the animals were treated weekly with LDE-DNR (6mg/kg, iv, n=9) or with LDE only (n=7). In addition, 3 animals without any intervention were used as a control group. Chow consumption, lipid and hematological profiles, body weight, and echocardiography were evaluated at baseline, pre-treatment and post-treatment. Morphometry and protein expression were performed to analyze the aortas. Results There was no difference in food intake and body weight for control, LDE and LDE-DNR groups. Total cholesterol, HDL-C, non-HDL-C and triglycerides increased in LDE and LDE-DNR groups when comparing baseline and post-treatment. Red blood cells decreased in LDE group at post-treatment in comparison to baseline, while LDE-DNR presented no such difference. Regarding aortic lesions of LDE-DNR group was 50% lower than LDE group. The protein expression of the inflammatory markers CD68, TNF-α and IL-6 in LDE-DNR was lower than LDE. Pro-apoptotic factors caspase 3, caspase 9 and BAX were also lower in LDE-DNR compared to LDE. Protein expression of vascular endothelial growth factor (VEGF) and vascular cell adhesion molecule (VCAM) was lower in the LDE-DNR group when compared to the LDE group. To test the cardiotoxicity of LDE-DNR, echocardiography was performed and observed that under LDE-DNR both systolic and diastolic function were preserved with no difference in cardiac mass in LDE-DNR when compared to control and LDE groups. However, LDE showed a significant increase in relative heart weight compared to control while LDE-DNR had no such difference. Treatment with LDE-DNR did not induce observable hematological toxicity. Conclusion The treatment with LDE-DNR reduced aortic lesions, diminished inflammatory and pro-apoptotic factors, diminished VCAM expression in the aorta and promoted cardiac preservation in a rabbit atherosclerosis model. In conclusion, LDE-DNR can be eligible for future developments in the quest for novel effective and safe treatments for atherosclerosis. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): FAPESP (Fundaçao de Amparo a Pesquisa do Estado de Sao Paulo)

Regression of Atherosclerotic Plaques of Cholesterol-Fed Rabbits by Combined Chemotherapy With Paclitaxel and Methotrexate Carried in Lipid Core Nanoparticles

2018 ◽  
Vol 23 (6) ◽  
pp. 561-569 ◽  
Author(s):  
Fernando L. T. Gomes ◽  
Raul C. Maranhão ◽  
Elaine R. Tavares ◽  
Priscila O. Carvalho ◽  
Maria L. Higuchi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Combined Chemotherapy ◽  
Cholesterol Feeding ◽  
Lipid Core ◽  
Atherosclerotic Lesions ◽  
Antiproliferative Agent ◽  
Factor Α ◽  
Core Nanoparticles

In previous studies, it was demonstrated that lipid core nanoparticles (LDE) resemble the low-density lipoprotein structure and carrying the antiproliferative agent paclitaxel (PTX) strongly reduced atherosclerosis lesions induced in rabbits by cholesterol feeding. Currently, the aim was to verify whether combining LDE-PTX treatment with methotrexate (MTX) associated with LDE (LDE-MTX) could accelerate the atherosclerosis regression attained with single LDE-PTX treatment, after withdrawing the cholesterol feeding. Thirty-eight rabbits were fed 1% cholesterol chow for 8 weeks. Six of these rabbits were then euthanized for analyses of the aorta (controls). In the remaining rabbits, cholesterol feeding was withdrawn, and those 32 animals were allocated to 3 groups submitted to different 8-week intravenous treatments, all once/week: LDE-PTX (n = 10; 4 mg/kg), LDE-PTX + LDE-MTX (n = 11; 4 mg/kg), and LDE-alone (n = 11). Rabbits were then euthanized and aortas were excised for morphometric, immunohistochemical, and gene expression analyses. After cholesterol feeding withdrawal, in comparison with LDE-alone group, both LDE-PTX and LDE-PTX + LDE-MTX treatments had the ability to increase the regression of plaque areas: −49% in LDE-PTX and −59% for LDE-PTX + LDE-MTX. However, only LDE-PTX + LDE-MTX treatment elicited reduction in the intima area, estimated in −57%. Macrophage presence in aortic lesions was reduced 48% by LDE-PTX and 43% by LDE-PTX + LDE-MTX treatment. Matrix metalloproteinase 9 was reduced by either LDE-PTX (74%) or LDE-PTX + LDE-MTX (78%). Tumor necrosis factor α gene expression was reduced 65% by LDE-PTX and 79% by LDE-PTX + LDE-MTX. In conclusion, treatment with LDE-PTX indeed accelerated plaque reduction after cholesterol feeding; LDE-PTX + LDE-MTX further increased this effect, without any observed toxicity. These results pave the way for the use of combined chemotherapy to achieve stronger effects on aggravated, highly inflamed atherosclerotic lesions.

scholarly journals Methotrexate associated with a lipid core nanoparticle prevented the dilation and dissection of the aortic arch in mice with Marfan syndrome

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M.C Guido ◽  
N.M Lopes ◽  
C.I Albuquerque ◽  
E.R Tavares ◽  
L Jensen ◽  
...  
Keyword(s):  
Protein Expression ◽  
Aortic Arch ◽  
Marfan Syndrome ◽  
Murine Model ◽  
Volume Fraction ◽  
Elastic Fiber ◽  
Funding Source ◽  
Lumen Area ◽  
Lipid Core ◽  
Fibrillin 1

Abstract Introduction Mutations in the fibrillin-1 gene result in dilation, dissection and rupture of the aorta, the main cause of mortality in patients with Marfan syndrome (MFS). Inflammation is associated with greater susceptibility to dissection and rupture of the aorta. Previously, we showed that methotrexate (MTX) carried in lipid core nanoparticles (LDE) had powerful anti-inflammatory and anti-proliferative effects on rheumatoid arthritis and atherosclerotic lesions induced in rabbits and improved myocardial infarction morphological and functional aspects in rats with ligation of left coronary artery. When MTX is associated to LDE, the uptake of the drug by the cells is increased several-fold, which conceivably endows MTX with enhanced action mechanisms and the drug toxicity is diminished. Purpose To investigate whether treatment with LDE-MTX can prevent the development of aortic arch lesions in a murine model of MFS. Methods mgΔloxPneo MFS murine model and wild-type mice were allocated in 3 groups of treatment: LDE only; MTX in commercial formulation; LDE-MTX. The treatment occurred weekly at a dose of 1mg/kg ip, between the 3rd and 6th month of life, period in which both dilation and dissection of the aortic arch are observed. After 12 weeks, the animals were submitted to echocardiography, morphometry and protein expression of the aortic arch. Results Compared to LDE and MTX groups, LDE-MTX treatment showed smaller lumen area of ascending and descending aorta and aortic arch segments in MFS mice. LDE-MTX also decreased the collagen volume fraction and the amount of aortic dissections, but did not affect the thickness of the vessel wall and the number of elastic fiber ruptures. The protein expression of the inflammatory markers CD68 (macrophages), CD3 (lymphocytes) and tumor necrosis factor alpha, of the apoptotic marker caspase 3 and of type 1 collagen were lower in MFS LDE-MTX group when compared to MFS mice treated with LDE and MTX. Moreover, treatment with LDE-MTX reduced TGF-β, ERK and the SMAD3 protein expression. Of note, CD68 and CD3 protein expression was positively correlated with the lumen area of the aortic arch (r2=0.36; p<0.001), indicating the importance of inflammation for the aortic dilation. The increase in bioavailability of intracellular adenosine in MFS animals treated with LDE-MTX was suggested by the higher expression of A2a adenosine receptor and the lower expression of adenosine deaminase in the aortic arch. Conclusion Possibly by increasing the bioavailability of intracellular adenosine, LDE-MTX treatment had the ability to reduce the processes of inflammation, apoptosis and fibrosis that are consequent to fibrillin-1 mutation. By these means, LDE-MTX may conceivably prevent the development of the dilation and dissection in the aortic arch, the hallmarks of MFS, in this animal model. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo)

Treatment with methotrexate carried in lipid core nanoparticles prevents the development of diastolic dysfunction in septic rats

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
N.M Lopes ◽  
M.C Guido ◽  
C.I Albuquerque ◽  
L Jensen ◽  
V.M Miura ◽  
...  
Keyword(s):  
Protein Expression ◽  
Diastolic Dysfunction ◽  
Cardiac Dysfunction ◽  
Density Lipoprotein ◽  
B Cell Lymphoma ◽  
Posterior Wall ◽  
The Other ◽  
Heart Weight ◽  
Control Group ◽  
Funding Source

Abstract Introduction In the development of sepsis, besides the dysregulation of the immune system and disturbances of several vital organs, life-threatening cardiac dysfunction often occurs. Previously, we showed that non-protein nanoparticles that resemble the lipid structure of low-density lipoprotein, termed LDE, concentrate in inflammatory sites. When incorporated in LDE, the cellular uptake of MTX increases several-fold compared to the uptake of commercial MTX. The novel LDE-MTX formulation was shown to have the ability to modulate the immune response in in rabbits with atherosclerosis and in rats with myocardial infarction. LDE-MTX reduced the inflammation and improved the post-infarction cardiac function by increasing the release of angiogenesis, thereby improving hypoxia. The aim of the current study was to test the hypothesis whether LDE-MTX could also improve the cardiac status in septic rats. Methods Septicemia was induced in Wistar rats by two I.P. injections of lipopolysaccharide (LPS, 10mg/kg) administered with a 24h interval. Rats were allocated to control group (CT, without sepsis; n=5) and 3 groups with sepsis: LDE (n=7), treated with LDE only; MTX (n=6), with commercial MTX (1mg/kg); and LDE-MTX (n=7), with LDE-MTX (1mg/kg). Echocardiography was performed 72h after sepsis induction. Animals were euthanised and LV tissues were collected for protein expression analysis of inflammatory, apoptotic, angiogenesis, hypoxia and adenosine bioavailability markers. Results Septic rats treated with LDE developed diastolic dysfunction and presented decreased diastolic volume and diameter of the LV. Treatment with LDE-MTX totally prevented the appearance of diastolic dysfunction and the alterations in LV diastolic dilation. Also, LDE-MTX treatment elicited cardiac hypertrophy through the increase of the thickness of septum and of the LV posterior wall. LDE-MTX increased LV mass and the relative heart weight, as compared to the other 3 groups. There were no differences in the protein expression of inflammatory (lymphocytes, tumor necrosis factor, interleukins) and apoptotic (caspases and B-cell lymphoma family) markers among the four groups. However, LDE-MTX showed higher expression of CD68 (macrophage marker). Angiogenesis was higher, while cellular hypoxia was lower in LDE-MTX, respectively represented by vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1 alpha, in comparison to the other 3 groups. The intracellular adenosine bioavailability was increased in LDE-MTX-treated animals, as promoted by the higher expression of the A1 receptor, as compared to CT. Conclusion The treatment with LDE-MTX was successful in precluding the appearance of the cardiac dysfunction associated to sepsis. This outcome was conceivably attained by different effects of the treatment observed here, such as those on angiogenesis, macrophage recruitment and adenosine bioavailability in the LV. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)

scholarly journals Early L-T4 intervention improves fetal heart development in pregnant rats with subclinical hypothyroidism rats by activating BMP4/Smad4 signaling pathway

2020 ◽  
Author(s):  
D Xue ◽  
JL Sun ◽  
J Yang
Keyword(s):  
Body Weight ◽  
Protein Expression ◽  
Signaling Pathway ◽  
Molecular Mechanism ◽  
Heart Development ◽  
Sham Group ◽  
Cardiac Development ◽  
Heart Weight ◽  
Pregnant Rats ◽  
Serum Tsh

Abstract Background: It is unclear whether the offspring of SCH pregnant rats still have abnormal cardiac development, and whether early intervention with L-T4 can improve the abnormality of these offspring. Therefore, the aim of this study was to investigate the effect of early L-T4 intervention on the heart development of offspring of SCH pregnant rats and its possible molecular mechanism. Methods: Eighty female Wistar rats were randomly divided into Sham group (placebo control), SCH group, LT4-E10 group (L-T4 treatment started on the 10th day of gestation), and LT4-E13 group (L-T4 treatment started on the 13th day of gestation). Each group was further divided into E16, E18, P5 (postnatal day 5 rats), and P10 (postnatal day 10 rats) subgroups. The levels of serum TT4 and TSH, the ratio of heart weight to body weight of offspring rats, the expression of metabolic enzymes, and the histopathology of cardiomyocytes were determined. To elucidate the effects of L-T4 on cardiac development of offspring of SCH pregnant rats, the expression levels of GATA4, Nkx2-5 and proteins involved in BMP4/Smad4 signaling pathway were detected by immunohistochemistry, real time quantitative polymerase chain reaction and Western blotting to elucidate the molecular mechanism of L-T4 regulating the heart development of the offspring of SCH pregnant rats. Results: Compared with Sham group, serum TSH was significantly increased in SCH pregnant rats. Moreover, early L-T4 intervention significantly reduced the levels of serum TSH. Compared with the offspring in the SCH group, early L-T4 intervention significantly increased the heart weight, heart weight to body weight ratio, the activities of succinate dehydrogenase (SDH), Na+/K+-ATPase and Ca2+-ATPase, but reduced myocardial cell shrinkage and nuclear staining, hyperemia/congestion and vacuolar degeneration. In addition, early L-T4 intervention not only significantly increased the mRNA and protein expression of Gata4 and Nkx2-5, but also increased the protein expression involved in BMP4/Smad4 signal pathway in myocardium of the offspring of SCH pregnant rats. Conclusions: Early L-T4 intervention can regulate the cardiac development of the offspring of SCH pregnant rats by activating BMP4/Smad4 signaling pathway and increasing the expression of Gata4 and Nkx2-5 proteins.

scholarly journals Early L-T4 intervention improves fetal heart development in pregnant rats with subclinical hypothyroidism rats by activating BMP4/Smad4 signaling pathway

2020 ◽  
Author(s):  
D Xue ◽  
JL Sun ◽  
J Yang
Keyword(s):  
Body Weight ◽  
Protein Expression ◽  
Signaling Pathway ◽  
Subclinical Hypothyroidism ◽  
Heart Development ◽  
Sham Group ◽  
Cardiac Development ◽  
Heart Weight ◽  
Pregnant Rats ◽  
Serum Tsh

Abstract Background: It is unclear whether the offspring of subclinical hypothyroidism (SCH) pregnant rats have abnormal cardiac development, and whether early intervention with L-T4 can improve the abnormality of these offspring. Therefore, the aim of this study was to investigate the effect of early L-T4 intervention on the heart development of offspring of SCH pregnant rats and its possible molecular mechanism. Methods: Eighty female Wistar rats were randomly divided into Sham group (placebo control), SCH group, LT4-E10 group (L-T4 treatment started on the 10th day of gestation), and LT4-E13 group (L-T4 treatment started on the 13th day of gestation). Each group was further divided into E16, E18, P5 (postnatal day 5 rats), and P10 (postnatal day 10 rats) subgroups. The levels of serum TT4 and TSH, the ratio of heart weight to body weight of offspring rats, the expression of metabolic enzymes, and the histopathology of cardiomyocytes were determined. To elucidate the effects of L-T4 on cardiac development of offspring of SCH pregnant rats, the expression levels of GATA4, Nkx2-5 and proteins involved in BMP4/Smad4 signaling pathway were detected by immunohistochemistry, real time quantitative polymerase chain reaction and Western blotting to elucidate the molecular mechanism of L-T4 regulating the heart development of the offspring of SCH pregnant rats. Results: Compared with Sham group, serum TSH was significantly increased in SCH pregnant rats. Moreover, early L-T4 intervention significantly reduced the levels of serum TSH. Compared with the offspring in the SCH group, early L-T4 intervention significantly increased the heart weight, heart weight to body weight ratio, the activities of succinate dehydrogenase (SDH), Na + /K + -ATPase and Ca 2+ -ATPase, but reduced myocardial cell shrinkage and nuclear staining, hyperemia/congestion and vacuolar degeneration. In addition, early L-T4 intervention not only significantly increased the mRNA and protein expression of Gata4 and Nkx2-5, but also increased the protein expression involved in BMP4/Smad4 signal pathway in myocardium of the offspring of SCH pregnant rats. Conclusions : Early L-T4 intervention can regulate the cardiac development of the offspring of SCH pregnant rats by activating BMP4/Smad4 signaling pathway and increasing the expression of Gata4 and Nkx2-5 proteins.

Abstract 13025: Methotrexate Carried in Lipid Core Nanoparticles Prevented the Dilation and Dissection of the Aortic Arch in Mice With Marfan Syndrome by Increasing the Bioavailability of Intracellular Adenosine

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Maria Carolina Guido ◽  
Natalia M Lopes ◽  
Camila I Albuquerque ◽  
Elaine R Tavares ◽  
Leonardo Jensen ◽  
...  
Keyword(s):  
Protein Expression ◽  
Aortic Arch ◽  
Marfan Syndrome ◽  
Volume Fraction ◽  
Elastic Fiber ◽  
Lumen Area ◽  
Necrosis Factor Alpha ◽  
Lipid Core ◽  
Fibrillin 1 ◽  
Core Nanoparticles

Introduction: Mutations in the fibrillin-1 gene result in aneurysms and rupture of the aorta, the main cause of mortality in patients with Marfan syndrome (MFS). Inflammation is associated with dissection and rupture of the aorta. We showed that methotrexate (MTX) carried in lipid core nanoparticles (LDE) had powerful anti-inflammatory effects on atherosclerotic lesions and myocardial infarction. Hypothesis: To investigate whether treatment with LDE-MTX can prevent the development of aortic arch lesions in MFS. Methods: mgΔloxPneo MFS murine model and wild-type mice were allocated in 3 groups of treatment: LDE only; MTX in commercial formulation; LDE-MTX. The treatment occurred weekly at a dose of 1mg/kg ip, between the 3rd and 6th month of life, period in which both dilation and dissection of the aortic arch are observed. After 12 weeks, animals were submitted to analysis of the aortic arch. Results: Compared to LDE and MTX groups, LDE-MTX treatment showed smaller lumen area of ascending and descending aorta and aortic arch segments in MFS mice. LDE-MTX also decreased collagen volume fraction and the amount of aortic dissections, but did not affect the thickness of the vessel wall and the number of elastic fiber ruptures. Protein expression of the inflammatory markers CD68 (macrophages), CD3 (lymphocytes) and tumor necrosis factor alpha, of the apoptotic marker caspase 3 and of type 1 collagen were lower in LDE-MTX group when compared to LDE and MTX. Moreover, treatment with LDE-MTX reduced TGF-β, ERK and SMAD3 protein expression. Of note, CD68 and CD3 protein expression were positively correlated with the lumen area of the aortic arch (r2=0.36; p<0.001), indicating the importance of inflammation for the aortic dilation. The increase in bioavailability of intracellular adenosine was suggested by higher expression of A2a adenosine receptor and lower levels of adenosine deaminase in the aortic arch. Conclusions: Possibly by increasing the bioavailability of intracellular adenosine, LDE-MTX treatment had the ability to reduce the processes of inflammation, apoptosis and fibrosis that are consequent to fibrillin-1 mutation. By these means, LDE-MTX may conceivably prevent the development of the dilation and dissection in the aortic arch, the hallmarks of MFS.

scholarly journals Early L-T4 Intervention Improves Fetal Heart Development in Pregnant Rats with Subclinical Hypothyroidism Rats by Activating BMP4/Smad4 Signaling Pathway

2020 ◽  
Author(s):  
D Xue ◽  
JL Sun ◽  
J Yang
Keyword(s):  
Body Weight ◽  
Protein Expression ◽  
Signaling Pathway ◽  
Molecular Mechanism ◽  
Heart Development ◽  
Sham Group ◽  
Cardiac Development ◽  
Heart Weight ◽  
Pregnant Rats ◽  
Serum Tsh

Abstract Background: It is unclear whether the offspring of SCH pregnant rats still have abnormal cardiac development, and whether early intervention with L-T4 can improve the abnormality of these offspring. Therefore, the aim of this study was to investigate the effect of early L-T4 intervention on the heart development of offspring of SCH pregnant rats and its possible molecular mechanism.Methods: Eighty female Wistar rats were randomly divided into Sham group (placebo control), SCH group, LT4-E10 group (L-T4 treatment started on the 10th day of gestation), and LT4-E13 group (L-T4 treatment started on the 13th day of gestation). Each group was further divided into E16, E18, P5 (postnatal day 5 rats), and P10 (postnatal day 10 rats) subgroups. The levels of serum TT4 and TSH, the ratio of heart weight to body weight of offspring rats, the expression of metabolic enzymes, and the histopathology of cardiomyocytes were determined. To elucidate the effects of L-T4 on cardiac development of offspring of SCH pregnant rats, the expression levels of GATA4, Nkx2-5 and proteins involved in BMP4/Smad4 signaling pathway were detected by immunohistochemistry, real time quantitative polymerase chain reaction and Western blotting to elucidate the molecular mechanism of L-T4 regulating the heart development of the offspring of SCH pregnant rats.Results: Compared with Sham group, serum TSH was significantly increased in SCH pregnant rats. Moreover, early L-T4 intervention significantly reduced the levels of serum TSH. Compared with the offspring in the SCH group, early L-T4 intervention significantly increased the heart weight, heart weight to body weight ratio, the activities of succinate dehydrogenase (SDH), Na+/K+-ATPase and Ca2+-ATPase, but reduced myocardial cell shrinkage and nuclear staining, hyperemia/congestion and vacuolar degeneration. In addition, early L-T4 intervention not only significantly increased the mRNA and protein expression of Gata4 and Nkx2-5, but also increased the protein expression involved in BMP4/Smad4 signal pathway in myocardium of the offspring of SCH pregnant rats.Conclusions: Early L-T4 intervention can regulate the cardiac development of the offspring of SCH pregnant rats by activating BMP4/Smad4 signaling pathway and increasing the expression of Gata4 and Nkx2-5 proteins.

scholarly journals B cell-specific GPR55 deficiency promotes atherosclerosis

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
R Guillamat-Prats ◽  
D Hering ◽  
M Rami ◽  
C Haerdtner ◽  
L Bindila ◽  
...  
Keyword(s):  
Body Weight ◽  
B Cells ◽  
B Cell ◽  
Mrna Expression ◽  
Cell Function ◽  
Metabolic Effects ◽  
Atherosclerotic Plaques ◽  
Funding Source ◽  
Sequencing Analysis ◽  
B Cell Function

Abstract Background Atherosclerosis is accompanied by an imbalance between resolving and pro-inflammatory lipid mediators. Targeting lipid signaling pathways might offer a new anti-inflammatory therapy for improving the clinical outcome in cardiovascular disease patients. We considered lysophosphatidylinositol (LPI) and its receptor G protein-coupled receptor (GPR)55 as a potential modulator of atherosclerosis. Its role in regulating atherosclerosis and B cell function is unknown. Hypothesis We assessed the hypothesis that GPR55 signaling causally affects atherosclerosis and whether it has a specific role in regulating B cell function in this disease. Methods Atherosclerotic plaques were compared between apolipoprotein E deficient (ApoE−/−) and ApoE−/−Gpr55−/− mice after 4 to 16 weeks Western Diet (WD; 0.15% cholesterol; n=12–15 per group). To specifically test the role of B cell GPR55 in atherosclerosis, we generated mixed chimeras by lethally irradiating low density lipoprotein receptor deficient (Ldlr−/−) mice and reconstituting with a mixture of μMT and wildtype (control) or μMT and Gpr55−/− bone marrow cells. Circulating B cells were sorted and bulk RNA sequencing analysis was performed. We performed lipid and immunostainings of murine aortic root plaques, qPCR and ELISA of tissue lysates, as well as multiplex analysis of plasma immunoglobulins. Leukocyte plasma and tissue counts were determined by flow cytometry. Results GPR55 expression in mouse and human atherosclerotic plaques was detected by immunostaining. Furthermore, we confirmed murine Gpr55 mRNA expression on sorted circulating B220+B cells via qPCR, which was higher compared to CD3+ T cells, while CD11+ myeloid cells as well as NK cells had only low Gpr55 mRNA levels. ApoE−/−Gpr55−/− mice had significantly larger plaques after 4&16 weeks WD compared to ApoE−/− controls, with more pronounced body weight increases and higher cholesterol levels at the 16 weeks WD time point. In addition, global Gpr55 deficiency resulted in enhanced aortic pro-inflammatory cytokine mRNA expression (IL-1β, IL-6, TNFα) and a massively upregulated IgG1 plasma levels and increased percentages of splenic germinal center and plasma cells. B-cell RNA-seq analysis showed 460 differential expressed regulated genes in the ApoE−/−Gpr55−/− compared to ApoE−/−. The main pathways affected were calcium ion transport, immunoglobulin production, negative regulation of phosphorylation, and cellular component morphogenesis, suggesting a dsysregulation of B cell function. B cell specific Gpr55 deficiency blunted the metabolic effects on body weight and cholesterol, but still translated in larger atherosclerotic plaques and elevated plasma IgG levels compared to the respective controls. Conclusion Both global and B cell-restricted Gpr55 deficiency promotes atherosclerosis and is associated with a more pro-inflammatory phenotype. Our findings suggest a novel role for GPR55 in regulating B cell development and function. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft (DFG)

scholarly journals Regression of gestational diabetes induced cardiomegaly in offspring of diabetic rat

2009 ◽  
Vol 24 (4) ◽  
pp. 251-255 ◽  
Author(s):  
Honório Sampaio Menezes ◽  
Cláudio Galeano Zettler ◽  
Alice Calone ◽  
Jackson Borges Corrêa ◽  
Carla Bartuscheck ◽  
...  
Keyword(s):  
Body Weight ◽  
Wistar Rats ◽  
Weight Ratio ◽  
Diabetic Rats ◽  
Heart Weight ◽  
Diabetic Rat ◽  
Control Group ◽  
Computer Assisted ◽  
Significant Difference ◽  
Levene Test

PURPOSE: To compare body weight and length, heart weight and length, heart-to-body weight ratio, glycemia, and morphometric cellular data of offspring of diabetic rats (ODR) and of normal rats (control). METHODS: Diabetes was induced in 3 pregnant Wistar rats, bearing 30 rats, on the 11th day after conception by intraperitoneal injection of 50 mg/kg of streptozotocin. Six normal pregnant Wistar rats, bearing 50 rats, made up the control group. Morphometric data were obtained using a scale for the weight, length, heart and body measurements. Morphometric cellular data were obtained by a computer assisted method applied to the measurements of myocytes. Statistical analysis utilized Student's t-test, ANOVA and Levene test. RESULTS: Control offspring had greater mean body weight and length than offspring of diabetic rats (p < 0.001). Heart weight and length and heart-to-body ratios of newborn rats differed between groups at birth (p < 0.001), but showed no difference at 21 days. Mean nuclei area and perimetric value of the myocytes decrees throughout the first 21 days of life (p < 0.01) in the diabetic group. CONCLUSIONS: Heart hypertrophy on the offspring of diabetic rats at birth was demonstrated by the significant difference between the groups. After the eleventh day, no difference was found, which confirmed regression of cardiomegaly. The significant difference between the first and the 21th day of life, for nuclei area feature, demonstrate regression of cardiac hypertrophy in the offspring of diabetic rats.

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