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Combination of LC-Q-TOF-MS/MS, network pharmacology, and nanoemulsion approaches identifies active compounds of two Artemisia species responsible for tackling early diabetes-related metabolic complications in the liver. PHYTOCHEMICAL ANALYSIS : PCA 2022; 33:1058-1067. [PMID: 35795911 DOI: 10.1002/pca.3159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 06/08/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
INTRODUCTION The chronicity of advanced glycation end-products (AGEs) imparts various damages resulting in metabolic dysfunction and diseases involving inflammation and oxidative stress. The use of plant extracts is of high interest in complementary medicine. Yet, extracts are multicomponent mixtures, and difficult to pinpoint their exact mechanism. OBJECTIVES We hypothesise that network pharmacology and bioinformatics can help experimental findings depict the exact active components and mechanism of action by which they induce their effects. Additionally, the toxicity and variability can be lowered and standardised with proper encapsulation methods. METHODOLOGY Here, we propose the formulation of phytoniosomes encapsulating two Artemisia species (Artemisia dracunculus and Artemisia absinthium) to mitigate AGEs and their induced cell redox dysregulation in the liver. Extracts from different solvents were identified via liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS/MS). Phytoniosomes were explored for their anti-glycating effect and modulation of AGE-induced damages in THLE-2 liver cells. Network pharmacology tools were used to identify possible targets and signalling pathways implicated. RESULTS Data demonstrated that A. absinthium phytoniosomes had a significant anti-AGE effect comparable to reference molecules and higher than A. dracunculus. They were able to restore cell dysfunction through the restoration of tumour necrosis alpha (TNF-α), interleukin 6 (IL-6), nitric oxide, and total antioxidant capacity. Phytoniosomes were able to protect cells from apoptosis by decreasing caspase 3 activity. Network pharmacology and bioinformatic analysis confirmed the induction of the effect via Akt-PI3K-MAPK and AGE-RAGE signalling pathways through quercetin and luteolin actions. CONCLUSION The current report highlights the potential of Artemisia phytoniosomes as strong contenders in AGE-related disease therapy.
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A chronic moderate methionine administration induced hyperhomocysteinemia associated with cardiovascular disease phenotype in the sand rat Psammomys obesus. Folia Histochem Cytobiol 2022; 60:111-124. [PMID: 35603572 DOI: 10.5603/fhc.a2022.0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 04/26/2022] [Accepted: 05/18/2022] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Cardiovascular diseases were defined as coronary artery, cerebrovascular, or peripheral arterial disease.Hyperhomocysteinemia (Hhcy) is an independent risk factor of cardiovascular diseases, including atherosclerosis. Our previous studies demonstrated the involvement of Hhcy in cardiovascular remodeling in the sand rat Psammomys obesus. MATERIAL AND METHODS An experimental Hhcy was induced, in the sand rat Psammomys obesus, by a daily intraperitoneal injection of 70 mg/kg of methionine for a total duration of 6 months. The impact of Hhcy on the cellular and matrix structures of the heart, aorta and liver was analyzed using histological techniques. Additionally we treated primary cultures of aortic smooth muscle cells (SMCs) with high concentration of methionine to investigate the effects of methionine at the cellular level. RESULTS A moderate Hhcy induced a significant increase in the extracellular matrix components particularly collagens which accumulated in the interstitial and perivascular spaces in the studied organs indicating a developing fibrosis. A liver steatosis was also observed following methionine treatment. Further analysis of the aorta showed that Hhcy also induced vascular alterations including SMCs reorientation and proliferation associated with aneurysm formation. CONCLUSIONS Our results show for the first time that Hhcy can induce a cardiovascular and liver diseases phenotype in Psammomys obesus, a species previously shown to be a good model for the studies of diabetes and other metabolism-related pathologies.
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Artemisia alleviates AGE-induced liver complications via MAPK and RAGE signaling pathways modulation: a combinatorial study. Mol Cell Biochem 2022; 477:2345-2357. [PMID: 35543857 DOI: 10.1007/s11010-022-04437-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 04/08/2022] [Indexed: 11/27/2022]
Abstract
Artemisia herba-alba (AHA) is a traditionally used plant to treat various diseases, including diabetes and metabolic dysfunctions. Plant extracts are generally explored empirically without a deeper assessment of their mechanism of action. Here, we describe a combinatorial study of biochemical, molecular, and bioinformatic (metabolite-protein pharmacology network) analyses to elucidate the mechanism of action of AHA and shed light on its multilevel effects in the treatment of diabetes-related advanced glycation end-products (AGE)-induced liver damages. The extract's polyphenols and flavonoids content were measured and then identified via LC-Q-TOF-MS/MS. Active compounds were used to generate a metabolite-target interaction network via Swiss Target Prediction and other databases. The extract was tested for its antiglycation and aggregation properties. Next, THLE-2 liver cells were challenged with AGEs, and the mechanistic markers were measured [TNF-α, IL-6, nitric oxide, total antioxidant capacity, lipid peroxidation (LPO), and caspase 3]. Metabolite and network screening showed the involvement of AHA in diabetes, glycation, liver diseases, aging, and apoptosis. Experimental confirmation showed that AHA inhibited protein modification and AGE formation. Additionally, AHA reduced inflammatory mediators (IL-6, TNFα), oxidative stress markers (NO, LPO), and apoptosis (Caspase 3). On the other hand, cellular total antioxidant capacity was restored to normal levels. The combinatorial study showed that AHA regulates AGE-induced liver damages through MAPK-AKT and AGE-RAGE signaling pathways. This report highlights the combination of experimental and network pharmacology for the exact elucidation of AHA mechanism of action as a multitarget option in the therapy of diabetes and AGEs-related diseases.
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Impact of the Living Donor Age and the Hormonal Profile of Algerian Renal Transplant Recipients. SAUDI JOURNAL OF KIDNEY DISEASES AND TRANSPLANTATION 2021; 32:1374-1381. [PMID: 35532707 DOI: 10.4103/1319-2442.344757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023] Open
Abstract
Kidney transplantation is the best treatment received by an uremic patient. One of the major advantages of transplantation is restoring a hormonal profile as before the chronic kidney disease. However, the posttransplant state depends on several factors including the quality of the graft. In this study, we assessed the donor age in living donors-recipients as well as the exploration of their hormonal profile. This is a single-center follow-up study over a period of 3 years, including 90 kidney recipients transplanted by living donors. We performed blood measurements of parathyroid hormone, prolactin, follicle stimulating hormone, luteinizing hormone, testosterone, estradiol, blood glucose, urea, creatinine, total cholesterol, triglycerides, high density lipoprotein-cholesterol, uric acid, albumin, and 24-h proteinuria. Glomerular filtration rate, body mass index, and low-density cholesterol were calculated. To analyze the donor age effect on recipients, the patients were divided into two groups according to donors age (<40 years and ≥40 years). The hormonal profile was normal for almost the majority of patients. In addition, we noted a return to dialysis associated with certain metabolic abnormalities and a donor age >40 years. Exploring the hormonal profile of the recipient is recommended. The donor age significantly influences the recipient fate but not their hormonal profile.
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Matrix metalloproteinase activities and oxidative stress in newborn cardiac tissue of rabbit female fed high cholesterol-methionine diet. Arch Physiol Biochem 2020; 126:23-30. [PMID: 30032654 DOI: 10.1080/13813455.2018.1489848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We study the effect of an enriched cholesterol-methionine diet administered to females on the cardiac tissue remodelling of the offspring during two successive pregnancies. Two groups are constituted, standard diet (SD) group fed a standard diet and CD group fed a combined diet (standard + cholesterol 1%-methionine 0.25%). The diet is administered during 80 days. The results show changes in serum and cardiac parameters of CD newborn, with the involvement of phospholipids (PLs) (phosphatidylethanolamine (PE) and phosphatidylcholine (PC), variations in malondialdehyde (MDA), conjugated diene (CD), and vitamin C [VIT-C] rates). Under the CD effect, serum matrix metalloproteinase (MMP)-2, pro-MMP-9, and MMP-9 activities change. As to cardiac MMP-2 activity, a rise is noticed in the second pregnancy. Histological analysis reveals constricted blood capillaries, collagen fibre deposits, and lipid accumulation in the CD newborn heart. Our study shows the amplified effect of the maternal cholesterol-methionine diet in the second pregnancy on newborn cardiac disorders (matrix remodelling, oxidative stress, and lipid accumulation).
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Hyperhomocysteinemia and myocardial remodeling in the sand rat, Psammomys obesus. Acta Histochem 2019; 121:823-832. [PMID: 31377002 DOI: 10.1016/j.acthis.2019.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 07/22/2019] [Accepted: 07/25/2019] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Numerous studies have shown that a methionine-rich diet induces hyperhomocysteinemia (Hhcy), a risk factor for cardiovascular diseases. The objective of the present study was to determine the involvement of Hhcy in cardiac remodeling in the sand rat Psammomys obesus. MATERIALS AND METHODS An experimental Hhcy was induced, in the sand rat Psammomys obesus, by intraperitoneal injection of 300 mg/kg of body weight/day of methionine for 1 month. The impact of Hhcy on the cellular and matricial structures of the myocardium was analyzed with histological techniques (Masson trichrome and Sirius red staining). Immunohistochemistry allowed us to analyze several factors involved in myocardial remodeling, such as fibrillar collagen I and III, metalloproteases (MMP-2 and -9) and their inhibitors (TIMP-1 and -2), TGF-β1 and activated caspase 3. RESULTS Our results show that Hhcy induced by an excess of methionine causes, in the myocardium of Psammomys obesus, a significant accumulation of fibrillar collagens I and III at the interstitial and perivascular scales, indicating the appearance of fibrosis, which is associated with an immuno-expression increase of TGF-β1, MMP-9 and TIMP-2 and an immuno-expression decrease of MMP-2 and TIMP-1. Also, Hhcy induces apoptosis of some cardiomyocytes and cardiac fibroblasts by increasing of activated caspase 3 expression. These results highlight a remodeling of cardiac tissue in hyperhomocysteinemic Psammomys obesus.
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Abstract
INTRODUCTION Elevated plasma homocysteine (Hcy) levels have been associated with several tissue injuries including heart and liver fibrosis. In these diseases, hyperhomocysteinemia (Hhcy) plays a major role in modulating the alteration of the balance between matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMPs), leading to the pathological accumulation of extracellular matrix (ECM) proteins. Since the effect of Hhcy on ECM of seminal vesicle was not studied, the aim of our research was to check if Hcy can induce a remodeling within seminal vesicles ECM. MATERIAL AND METHODS The study was conducted in 22 adult male Wistar rats. The rats were divided into two groups: a control group, which received standard diet and tap water; the treated group received the same diet and water supplemented with solution of L-methionine (200 mg/kg b.w./day) for 6 months. Plasma homocysteine concentration was measured. Histological changes were observed with light microscope. The presence of collagen I and III and metalloproteinases (2, 3, 7 and 9) in the seminal vesicles was examined using immunohistochemistry and Western blotting. RESULTS Plasma Hcy levels increased significantly after methionine treatment and interfered significantly with body weight in treated rats. The content of fibrillar collagens (I and III) in the wall of seminal vesicles was elevated in hyperhomocysteinemic rats. Moreover, we found that hyperhomocysteinemia increased the expression of MMP-2, -3, -7 and -9 in seminal vesicles of experimental rats. CONCLUSIONS Increased plasma concentration of Hcy accompanied by the accumulation of collagen and upregulation of MMPs in rat seminal vesicles might contribute to the remodeling of seminal vesicles.
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Impact d’une hyperhomocystéinémie sur la structure hépatique du rat des sables, Psammomys obesus. NUTR CLIN METAB 2016. [DOI: 10.1016/j.nupar.2016.09.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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0323 : Atherogen effect of hyperhomocysteinemia induced by chronic administration of DL-methionine on male rabbits. ARCHIVES OF CARDIOVASCULAR DISEASES SUPPLEMENTS 2016. [DOI: 10.1016/s1878-6480(16)30367-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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0327 : Impact of a high fat diet on plasma and heart biochemical parameters of prepubertal male and female rabbits. ARCHIVES OF CARDIOVASCULAR DISEASES SUPPLEMENTS 2016. [DOI: 10.1016/s1878-6480(16)30394-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Hepatoprotective effects of lycopene on liver enzymes involved in methionine and xenobiotic metabolism in hyperhomocysteinemic rats. Food Funct 2016; 7:2862-9. [DOI: 10.1039/c6fo00095a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hyperhomocysteinemia, defined by an increased plasma homocysteine level, is commonly associated with chronic liver diseases.
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P277: Impact de l’hyperhomocysteinemie sur la gonade du lapin mâle. NUTR CLIN METAB 2014. [DOI: 10.1016/s0985-0562(14)70919-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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P122: Surcharge en méthionine, altérations plasmatiques et tissulaires et stress oxydant chez Rattus Norvegicus. NUTR CLIN METAB 2014. [DOI: 10.1016/s0985-0562(14)70764-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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P136 Toxicité de l’hyperhomocysteinémie sur le foie. NUTR CLIN METAB 2013. [DOI: 10.1016/s0985-0562(13)70468-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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P064 Hyperhomocystéinémie induite et tissu cardiaque. NUTR CLIN METAB 2013. [DOI: 10.1016/s0985-0562(13)70396-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Oestrus induction in primiparous lactating rabbits by a 48 hours mother-litter separation: endocrine and behavioural responses. WORLD RABBIT SCIENCE 2013. [DOI: 10.4995/wrs.2013.1248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Hyperhomocysteinemia-induced Dyrk1a downregulation results in cardiomyocyte hypertrophy in rats. Int J Cardiol 2010; 145:306-307. [PMID: 19906449 DOI: 10.1016/j.ijcard.2009.10.043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Accepted: 10/18/2009] [Indexed: 02/04/2023]
Abstract
Cardiac hypertrophy has been demonstrated in rat models of hyperhomocysteinemia, a major risk factor for chronic heart failure. As one of the molecular pathway which leads to cardiac hypertrophy is mediated by the serine-threonine kinase DYRK1A, we have determined the expression of Dyrk1a in the heart of hyperhomocysteinemic rats and found that hyperhomocysteinemia in rats not only induced ventricular cardiomyocyte hypertrophy but also decreased protein Dyrk1a expression. The decreased expression of Dyrk1a could be consistent with decreased antihypertrophic effects of Dyrk1a leading to cardiomyocyte hypertrophy in case of hyperhomocysteinemia.
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Myocardial fibrosis and TGFB expression in hyperhomocysteinemic rats. Mol Cell Biochem 2010; 347:63-70. [DOI: 10.1007/s11010-010-0612-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2010] [Accepted: 09/28/2010] [Indexed: 12/25/2022]
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Immunoexpression of gelatinase (MMP-2 and MMP-9) in the seminal vesicles and ventral prostate of Libyan jird (Meriones libycus) during the seasonal cycle of reproduction. Histol Histopathol 2010; 25:619-36. [PMID: 20238300 DOI: 10.14670/hh-25.619] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
An immunohistochemical study of matrix metalloproteinases (MMP-2 and MMP-9) or gelatinase (gelatinase A and gelatinase B) was performed on the seminal vesicles and ventral prostate of the Libyan jird (Meriones libycus) collected in the Beni-Abbes area during breeding period (spring and early summer), during resting phase (late summer, autumn, winter) and from castrated animals in the spring. The work was done using the indirect immunohistochemistry protocol by amplification with streptavidin-biotin-peroxidase and AEC as chromogen. In the seminal vesicles, during the breeding period, an important immunohistochemical signal of MMP-2 and MMP-9 was observed in epithelial cells and smooth muscle cells (SMC) without any immunoexpression in the extracellular matrix (ECM) and secretion. During resting phase and in thirty days castrated Meriones libycus, the MMP-2 and MMP-9 immunoexpression was weak in the epithelial cells and persisted with the same intensity in the SMC. The ECM, with no immunostaining in active season, showed a pronounced immunoresponse of both the two gelatinase. Three days after castration, the MMP-9 immunohistochemical reaction in epithelial cells and SMC was as intense as during active season. A prolonged castration of 50 and 90 days resulted in the maintenance of the MMP-9 immunostaining in epithelial cells and SMC and its disappearance from the ECM, suggesting a slow process of regression. During the breeding period, in the ventral prostate, MMP-2 immunostaining was more important in the SMC than in epithelial cells. The MMP-9 immunoexpression pattern was the opposite, the epithelial cells showed a higher immunoreaction than SMC. ECM and secretion lacked MMP-2 and MMP-9 immunostaining. The ventral prostate lumen contained a granular secretion without any gelatinase immunolabelling and was hollowed by empty circular forms reflecting the disappearance of the product in these areas. Part of the secretion showed a positive MMP-2 and MMP-9 immunoreaction. The latter was subsequently filled and seemed involved in the progression of the secretion in the tubules, preventing their filling. In resting phase and in animals castrated since thirty days, the immunoreactivity of both the two gelatinases was maintained in the epithelial cells and in the SMC, and was absent in the ECM. The gelatinases are involved in the seasonal reproductive cycle of Meriones libycus.
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Effects of cafeine and theophylline on lipolysis in isolated adipocytes of diabetic rats. Exp Clin Endocrinol Diabetes 2009. [DOI: 10.1055/s-0029-1211831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Tu-P7:45 Psammomys obesus, animal model of atherosclerosis. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)80753-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Effect of high glucose concentration on collagen synthesis and cholesterol level in the phenotypic modulation of aortic cultured smooth muscle cells of sand rat (Psammomys obesus). EXPERIMENTAL DIABESITY RESEARCH 2005; 5:227-35. [PMID: 15512791 PMCID: PMC2478628 DOI: 10.1080/15438600490489793] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To simulate diabetic conditions, the effects of high glucose
concentration on collagen synthesis and cholesterol
level in cultured aortic smooth muscle cells of Psammomys
were investigated. For collagen biosynthesis, smooth muscle
cells (SMCs) were incubated in synthetic proliferative
phase and in postconfluent phase with 3H-proline. Cellular
cholesterol was determined by enzymatic method. Under
high glucose concentration, the results showed morphological
modifications characterized by morphometric cellular,
nuclear, and nucleolar changes. In biochemical studies, the
authors observed an increase of free and esterified cellular
cholesterol as well as of total proteins, collagen biosynthesis,
and α1 (I+III) and α2 (I) chains of collagen contained
in the SMCs and in the extracellular matrix. These results
showed the sensitivity of Psammomys aortic SMCs to high
glucose concentration and would constitute an interesting
cellular model to study atherosclerosis pathogeny in experimental
diabetes.
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MESH Headings
- Animals
- Aorta/metabolism
- Aorta/pathology
- Cells, Cultured
- Cholesterol/metabolism
- Collagen/biosynthesis
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Gerbillinae
- Glucose/administration & dosage
- Glucose/pharmacology
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Osmolar Concentration
- Phenotype
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Abstract
The extracellular matrix provides a structural framework essential for the functional properties of vessel walls. The three dimensional organization of the extracellular matrix molecules--elastin, collagens, proteoglycans and structural glycoproteins--synthesized during fetal development--is optimal for these functions. Early in life, the vessel wall is subjected to injury: lipid deposition, hypoxia, enzyme secretion and reactive oxygen species production during inflammatory processes, and the extracellular matrix molecules are hydrolyzed by proteases--matrix metalloproteinases, leukocyte elastase, etc. In uninjured arteries and veins, some proteases are constitutively expressed, but through the control of their activation and/or their inhibition by inhibitors, these proteases have a very low activity. During the occurrence of vascular pathologies--atherosclerosis, hypertension, varicosis, restenosis, etc.--the balance between proteases and their inhibitors is temporally destroyed through the induction of matrix metalloproteinase gene expression or the secretion of enzymes by inflammatory cells. Smooth muscle cells, the most numerous cells in vascular walls, have a high ability to respond to injury through their ability to synthesize extracellular matrix molecules and protease inhibitors. However, the three dimensional organization of the newly synthesized extracellular matrix is never functionally optimal. In some other pathologies--aneurysm--the injury overcomes the responsive capacity of smooth muscle cells and the quantity of extracellular matrix decreases. In conclusion, care should be taken to maintain the vascular extracellular matrix reserve and any therapeutic manipulation of the protease/inhibitor balance must be perfectly controlled, because an accumulation of abnormal extracellular matrix may have unforeseen adverse effects.
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Effect of high-glucose concentrations on the expression of collagens and fibronectin by fibroblasts in culture. Exp Gerontol 1998; 33:445-55. [PMID: 9762522 DOI: 10.1016/s0531-5565(98)00015-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Extracellular matrix macromolecules such as collagen and fibronectin are progressively altered during aging and age-related diseases like diabetes. We investigated the effect of high-glucose concentration (mimicking diabetic conditions) and the influence of in vitro cell aging [comparing 4th-passage fibroblasts (P4) to 15th-passage fibroblasts (P15)] on collagen and fibronectin synthesis. Fibroblasts were incubated at postconfluency with radiolabeled precursors, [3H] proline for collagen, [35S] methionine for fibronectin. We report that in control conditions (5 mM glucose) collagen III production increased with in vitro cell aging. High glucose concentrations (10 and 15 mM) increased specifically collagen III synthesis both at the mRNA and protein levels, without alteration of collagen I production in P4 and P15 cells. Fibronectin synthesis was also increased both during in vitro cell aging and in high glucose-treated P4 fibroblasts. Taken together, these data suggest similarities between changes of phenotypic expression of collagen and fibronectin induced by in vitro cell aging and conditions imitating diabetes.
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Abstract
The effect of specifically derivatized dextrans, with or without antiproliferative activity on smooth muscle cells (SMC), was investigated on type I and type III collagen biosynthesis and mRNA levels in post-confluent SMC cultures. Our results indicate that dextran derivatives decreased total protein and collagen synthesis independently of their antiproliferative activities. However, the most substituted dextran, the one exhibiting the strongest antiproliferative activity towards SMC, was the most active in modulating type III collagen expression. In addition, only the two dextran derivatives bearing benzylamide groups inhibited collagen excretion.
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