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1.
Biomedicines ; 11(2)2023 Feb 19.
Article in English | MEDLINE | ID: mdl-36831160

ABSTRACT

Behçet disease (BD) is a multisystemic disease that commonly involves the eyes. Although it affects patients in all age groups, data on ocular disease by age of onset are limited. This retrospective, multicenter study aimed to compare epidemiology, systemic and ocular manifestations, treatments and outcomes between three age groups: juvenile (<18 years), adult (18-39 years) and late (≥40 years) disease onset. The study included 175 ocular BD patients (303 eyes) from Israel and Palestine: juvenile-onset (n = 25, 14.3%), adult-onset (n = 120, 68.6%) and late-onset (n = 30, 17.1%). Most patients in all groups were male. Systemic manifestations were similar in all groups. Systemic co-morbidities were more common in late-onset patients. Bilateral panuveitis was the most common ocular manifestation in all patients. Non-occlusive retinal vasculitis, peripheral vessel occlusions, cataract and elevated intraocular pressure were found more commonly among juvenile-onset eyes. Anterior uveitis and macular ischemia were most common among late-onset eyes, while branch retinal vein occlusion was most common in adult and late-onset eyes. All patients were treated with corticosteroids. Methotrexate, immunomodulatory combinations and biologic treatments were more commonly used for juvenile-onset patients. All groups had a similar visual outcome. Our study showed that patients with ocular BD have varied ocular manifestations and require different treatments according to age of disease onset, but visual outcome is similar.

2.
Acta Ophthalmol ; 101(6): 619-626, 2023 Sep.
Article in English | MEDLINE | ID: mdl-36750991

ABSTRACT

PURPOSE: The literature on retinal vascular occlusions in Behçet disease (BD) patients is limited. The aim of this study is to thoroughly investigate retinal vascular occlusions among ocular BD patients. METHODS: Retrospective, multicentre case-control study. Three-hundred and three eyes of 175 patients with ocular BD, from 13 hospitals in Israel and Palestine, were included. Patients were assigned into two groups according to the presence of retinal vascular occlusion. Epidemiology, systemic and ocular manifestations, treatments and outcomes were compared between the groups and risk factors for retinal vascular occlusions were identified. RESULTS: One hundred twenty-five patients (71.4%) were male. The mean age at presentation was 28.2 ± 0.86 years. Retinal vascular occlusions were found in 80 eyes of 54 (30.9%) patients, including branch retinal vein occlusion (51.3%), peripheral vessels occlusions (32.5%), central retinal vein occlusion (13.8%) and arterial occlusions (7.5%). Systemic manifestations were similar among both groups. Anterior uveitis was more common in non-occlusive eyes (p < 0.01). Non-occlusive retinal vasculitis (p = 0.03) and ocular complications were more common in occlusive eyes (p < 0.01). Treatments including mycophenolate mofetil, Infliximab or a combination therapy of anti-metabolite and calcineurin inhibitor were more commonly used by occlusive patients (p < 0.05). Occlusive patients underwent more cataract surgeries (p = 0.03). The occlusive group had worse mean best-corrected visual acuity (BCVA) throughout follow-up (p < 0.01). Risk factors for retinal vascular occlusions included male sex and Jewish ethnicity (p < 0.05). CONCLUSION: Retinal vascular occlusions were found in a third of ocular BD patients. Occlusive eyes had a worse prognosis. Risk factors for vascular occlusions were identified.


Subject(s)
Behcet Syndrome , Retinal Artery Occlusion , Retinal Vein Occlusion , Humans , Male , Adult , Female , Behcet Syndrome/complications , Behcet Syndrome/diagnosis , Behcet Syndrome/epidemiology , Retinal Artery Occlusion/diagnosis , Retinal Artery Occlusion/epidemiology , Retinal Artery Occlusion/etiology , Retrospective Studies , Case-Control Studies , Retinal Vein Occlusion/diagnosis , Retinal Vein Occlusion/epidemiology , Retinal Vein Occlusion/etiology
3.
J Diabetes Res ; 2022: 8337823, 2022.
Article in English | MEDLINE | ID: mdl-36313818

ABSTRACT

Background: Type 2 diabetes mellitus (T2DM), especially hyperglycemia, is associated with increased glucose cell toxicity and oxidative stress that can lead to irreversible damage in the kidney such as diabetic nephropathy (DN). Autophagy plays a key role in the degradation of damaged intracellular proteins in order to maintain intracellular homeostasis and cell integrity. The disturbance of autophagy is involved in the pathogenesis of diabetic nephropathy. We aim to investigate the molecular effect of sodium-glucose transporter 2 inhibitor (SGLT2i) on the expression of ATG5 and its downstream collaborator LC3-II in diabetic nice model. Material and Methods. We used eight weeks old male mice: twenty C57BL/6 wild type (C57BL/6), twenty BTBR ob/ob (DM), and twenty BTBR ob/ob that were treated with empagliflozin (DM+EMPA), FDA approved SGLT2i. Lysate from murine renal cortex was analyzed by Western blot and immunohistochemistry. ATG5, LC3B, and fibronectin expression were analyzed in murine kidney tissues. All mice were sacrificed 13 weeks after the beginning of the experiment. Results: Histological and Western blot analyses reveal decrease ATG5, LC3-II, and fibronectin levels at renal specimens taken from DM mice. EMPA treatment reduced T2DM mice body weight and blood glucose and increased urine glucose. Further, it upregulated all of the abovementioned proteins. Conclusions: Hyperglycemia reduces LC3-II and ATG5 protein levels which contribute to deficiencies in the autophagy process, with development and progression of DN. SGLT2i significantly reduces progression of DN and onset of end-stage renal disease in T2DM patients, probably through its effect on autophagy.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetic Nephropathies , Hyperglycemia , Sodium-Glucose Transporter 2 Inhibitors , Male , Mice , Animals , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetic Nephropathies/metabolism , Fibronectins , Mice, Inbred C57BL , Blood Glucose/metabolism , Autophagy , Hyperglycemia/metabolism
4.
Diab Vasc Dis Res ; 18(6): 14791641211062050, 2021.
Article in English | MEDLINE | ID: mdl-34903064

ABSTRACT

BACKGROUND: Autophagy is a catabolic mechanism that involves lysosomal-dependent degradation of unnecessary intracellular components and responsible for normal cellular homeostasis. Autophagy pathway and its key participant ATG5/LC3 are associated with several pathologies such as diabetes mellitus and its complications. METHODS: Levels and expression of autophagy key components ATG5 and LC3B were analyzed in both human model and murine tissues. One hundred and twenty human subjects were divided into four groups: Healthy (control), diabetes mellitus without complications, diabetic nephropathy, and diabetic retinopathy. Additionally, we used kidneys from WT healthy and diabetic nephropathy mice. Lysate derived from human peripheral blood mononuclear cells and murine renal cortex lysates were subjected to western blot and immunohistochemical analysis. RESULTS: Western blot and immunohistochemical analysis demonstrate that ATG5 protein levels were significantly decreased in diabetes mellitus, diabetic nephropathy (DN), and diabetic retinopathy patients versus healthy controls and in DN mice compared to healthy mice (0.65 ± 0.04; 1.15 ± 0.13 A.U. units, respectively). Quantification of staining area (%) of ATG5 mice tissue expression also decreased in DN versus healthy mice (4.42 ± 1.08%; 10.87 ± 1.01%, respectively). LC3B LEVELS AND EXPRESSION: Significant reduction in peripheral blood mononuclear cells in diabetic patients (with or without complications) vs. healthy controls. Renal LC3B levels were lower in DN versus healthy mice (0.36 ± 0.03; 0.68 ± 0.07 A.U. units). Renal LC3B staining quantification revealed significant reduction in DN versus healthy mice (1.7 ± 0.23%; 8.56 ± 1.7%). CONCLUSION: We conclude that ATG5, as well as LC3B, are down regulated in diabetic patients with or without complications. This diminution contributes to deficiencies in the autophagy process.


Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Animals , Autophagy , Autophagy-Related Protein 5/genetics , Diabetic Nephropathies/genetics , Gene Expression , Humans , Leukocytes, Mononuclear , Mice
5.
Harefuah ; 160(11): 740-745, 2021 Nov.
Article in Hebrew | MEDLINE | ID: mdl-34817141

ABSTRACT

INTRODUCTION: Diabetes mellitus (DM) is the leading cause of end stage renal disease; 40% of the patients worldwide will require replacement therapy after 20 years of DM. Early-stage diabetic nephropathy is characterized by hyper filtration with micro-and macro albuminuria. Later on end-stage renal disease (ESRD) can appear; 40% of diabetic patients develop micro-and macrovascular complications, with increased risk among patients with genetic predisposition, such as Haptoglobin 2-2 phenotype. The most frequent complications are diabetic kidney disease, diabetic retinopathy and coronary artery disease. Chronic systemic inflammation and the inflammatory response, such as increased circulating cytokines have been recognized as main players in the development and progression of diabetic nephropathy. DM is also associated with increased oxidative stress, and alterations in carbohydrate, lipid and protein metabolism. Blocking the renin- angiotensin- aldosterone system (RAAS) is not sufficient to delay the progression of DM. Autophagy may be involved in the pathogenesis of diabetic nephropathy. Under normal blood glucose level, autophagy is an important protective mechanism in renal epithelial cells, including podocytes, proximal tubular, mesangial and endothelial cells. Down regulation of the autophagy mechanism, as in hyperglycemic condition, can contribute to the development and progression of DM. The recently used new family of drugs SGL2Tis (sodium-glucose cotransporter-2 inhibitors) reduces the typical glomerular hyper-filtration. Preclinical and clinical studies focusing on SGLT2I treatment have consistently demonstrated a reduction in albuminuria and maintenance of renal function. SGLT2 inhibition may lead to positive molecular changes in podocyte cells and proximal tubule cells by directly affect basal autophagy.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetic Nephropathies , Sodium-Glucose Transporter 2 Inhibitors , Autophagy , Diabetic Nephropathies/etiology , Endothelial Cells , Humans
6.
Ir J Med Sci ; 190(4): 1271-1274, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33409846

ABSTRACT

SARS-CoV-2, causing the lethal disease COVid-19, is a public health emergency in the 2020 global pandemic. The outbreak and fast spreading of SARS-CoV-2 have a high morbidity and mortality specifically in elder patients with chronic diseases such as diabetes mellitus, arterial hypertension, chronic kidney disease, and organ transplanted patients with immunosuppressive therapy. Preliminary results support different treatments such as chloroquine and convalescent plasma infusion in severe cases, with good outcome. On the other hand, the efficacy of supplementation with active vitamin D, an immunomodulator hormone with antiinflammatory and antimicrobial effects, is unproven. A recent study reported that vitamin D attains antiviral effects, via blocking viral replication directly. SARS-CoV-2 primarily uses the immune evasion process during infection via the envelope spike glycoprotein, which is followed by a cytokine storm, causing severe acute respiratory disease syndrome and death. SARS-CoV-2, by using the well-known angiotensin-converting enzyme 2 by the protein spike, as the host receptor to enter into alveolar, myocardial, and renal epithelial cells, can be disrupted by vitamin D. However, the correlation between vitamin D levels and COVID-19 deaths in previous studies was insignificant. Retrospective studies demonstrated a correlation between vitamin D status and COVID-19 severity and mortality, while other studies did not find this correlation. Studies have shown that, vitamin D reduces the risk of acute viral respiratory tract infections and pneumonia via direct inhibition of viral replication, antiinflammatory and immunomodulatory effects. The data available today regarding the beneficial protective effect of vitamin D is unclear and with conflicting results. Large randomized control trials are necessary to test this hypothesis. In this review, we will explain the cross talk between the active vitamin D and the angiotensin-converting enzyme 2, and summarize the data from the literature.


Subject(s)
COVID-19 , Aged , COVID-19/therapy , Dietary Supplements , Humans , Immunization, Passive , Retrospective Studies , SARS-CoV-2 , Vitamin D/therapeutic use , COVID-19 Serotherapy
7.
J Diabetes Res ; 2020: 7907605, 2020.
Article in English | MEDLINE | ID: mdl-33294462

ABSTRACT

BACKGROUND: Diabetic nephropathy (DN) is one of the most common microvascular complications of diabetes and is the leading cause of end-stage renal disease (ESRD) and replacement therapy worldwide. Vitamin D levels in DN patients are very low due to the decrease in the synthesis and activity of 1-α hydroxylase in the proximal tubule cells and decrease in the vitamin D receptor abundance. To date, few studies have shown the antioxidant effects of 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] on hyperglycemia-induced renal injury. The selective activator of the vitamin D receptor, paricalcitol, reduces proteinuria and slows the progression of kidney injury. The precise mechanism through which vitamin D affects diabetic status and provides kidney protection remains to be determined. METHODS: Diabetes mellitus (DM) was induced in 94 8-week-old DBA/2J mice by intraperitoneal injection of streptozotocin (STZ). DM mice were randomly divided into receiving vehicle or treatment with paricalcitol, the active vitamin D analog, 1 week after DM induction or paricalcitol treatment 3 weeks after DM induction. An additional control group of healthy wild-type mice was not treated. Urine albumin, blood urea nitrogen, and creatinine levels were measured before and at the end of the paricalcitol treatment. Periodic acid-Schiff, immunohistochemistry staining, and western blot of the renal tissues of vitamin D receptor, villin, nephrin, and podocin expressions, were analyzed. RESULTS: Paricalcitol treatment restored villin, nephrin, and podocin protein levels that were downregulated upon DM induction, and reduced fibronectin protein level. Vitamin D receptor activation by paricalcitol may reduce proteinuria of DN in mice and alleviate high-glucose-induced injury of kidney podocytes by regulating the key molecules such nephrin-podocin. CONCLUSIONS: Paricalcitol treatment was associated with improved structural changes in type 1 diabetic mice including upregulation of vitamin D receptor expression, and decreased fibrosis markers such as fibronectin. These effects may contribute to the consistent benefit of vitamin D analog to slow the deterioration in glomerular function and reduce the risk of ESRD in patients with type 1 and 2 diabetes mellitus. Our results suggest that additional use of paricalcitol may be beneficial in treating patients with diabetes under standard therapeutic strategies.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetic Nephropathies/prevention & control , Ergocalciferols/pharmacology , Kidney/drug effects , Proteinuria/prevention & control , Receptors, Calcitriol/agonists , Animals , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetic Nephropathies/etiology , Diabetic Nephropathies/metabolism , Diabetic Nephropathies/pathology , Disease Progression , Fibronectins/metabolism , Fibrosis , Kidney/metabolism , Kidney/pathology , Mice, Inbred DBA , Proteinuria/etiology , Proteinuria/metabolism , Proteinuria/pathology , Receptors, Calcitriol/metabolism , Streptozocin
8.
Int Urol Nephrol ; 52(9): 1705-1712, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32661628

ABSTRACT

Diabetes mellitus (DM) is the leading cause of end stage renal disease. 40% of the patients worldwide will require replacement therapy after 20 years of DM worldwide. Early-stage diabetic nephropathy is characterized by hyperfiltration related to hypeglycemia-induced afferent artery vasodilatation with micro-and macroalbuminuria. Later on, proteinuria with arterial hypertension may appear, culminating in glomerular filtration rate (GFR) decline and end stage renal disease. Forty percent of diabetic patients develop microvascular and macrovascular complications, with increased risk among patients with genetic predisposition, such as Haptoglobin 2-2 phenotype. The most frequent complications in the daily clinical practice are diabetic kidney disease, diabetic retinopathy and vascular disease, such as coronary artery disease and stroke. Various pathways are involved in the pathogenesis of diabetic kidney disease. Chronic systemic inflammation and the inflammatory response, such as increased circulating cytokines (Interleukins), have been recognized as main players in the development and progression of diabetic kidney disease. DM is also associated with increased oxidative stress, and alterations in carbohydrate, lipid and protein metabolism. Overexpression of the renin-angiotensin-aldosterone system (RAAS) in the kidney, the vitamin D-Vitamin D receptor-klotho axis, and autophagy. Differences in the ATG5 protein levels or ATG5 gene expression involved in the autophagy process have been associated with diabetic complications such as diabetic kidney disease. Under normal blood glucose level, autophagy is an important protective mechanism in renal epithelial cells, including podocytes, proximal tubular, mesangial and endothelial cells. Down regulation of the autophagic mechanism, as in hyperglycemic condition, can contribute to the development and progression of diabetic kidney disease.


Subject(s)
Autophagy , Diabetic Nephropathies/physiopathology , Autophagy/physiology , Diabetic Nephropathies/complications , Humans
9.
Eur J Ophthalmol ; 30(3): 533-537, 2020 May.
Article in English | MEDLINE | ID: mdl-30935238

ABSTRACT

PURPOSE: The aim of this study was to investigate the incidence of clinically significant anterior chamber inflammation in a combined surgery, namely, phacoemulsification and Ex-Press miniature glaucoma device implantation, compared to phacoemulsification alone. METHODS: A retrospective comparative study of a consecutive series of 210 participants above 18 years of age diagnosed with significant cataract and who required glaucoma surgery, namely, Ex-Press miniature glaucoma device implantation or cataract alone in one or both eyes. All were operated on by a single experienced glaucoma surgeon in a single medical center. A total of 231 eyes were included in this study. All cases underwent an uneventful surgery and were examined the day following the surgery for visual acuity, intraocular pressure, and signs of excessive anterior chamber inflammation (Standardization of Uveitis Nomenclature grading ⩾ 3). RESULTS: The combined group included 55 eyes of 51 patients, of whom 15 (27.3%) demonstrated excessive anterior chamber inflammation. The phacoemulsification group included 176 eyes of 159 patients, of whom 12 (6.7%) demonstrated excessive anterior chamber inflammation. Visual acuity and intraocular pressure measurements showed no statistically significant difference between the two groups. CONCLUSION: The Ex-Press glaucoma device is efficient, safe, and known for its inert nature. However, combination of this procedure with phacoemulsification surgery might result in a condition encouraging excessive inflammation, which eventually could lead to excessive anterior chamber inflammations if not treated vigorously. Emphasizing and recognizing the risks, especially in glaucoma patients, is important.


Subject(s)
Anterior Chamber/pathology , Cataract/complications , Glaucoma Drainage Implants , Glaucoma, Open-Angle/complications , Inflammation/etiology , Phacoemulsification , Postoperative Complications , Adult , Aged , Aged, 80 and over , Female , Glaucoma, Open-Angle/surgery , Humans , Inflammation/diagnosis , Intraocular Pressure/physiology , Lens Implantation, Intraocular , Male , Middle Aged , Retrospective Studies , Tonometry, Ocular , Visual Acuity/physiology
10.
Ocul Immunol Inflamm ; 27(3): 410-417, 2019.
Article in English | MEDLINE | ID: mdl-29333911

ABSTRACT

Purpose: To describe the distribution, clinical findings, visual outcomes, treatment, and complications of children with uveitis at a tertiary referral ophthalmic center. Methods: Retrospective cohort study. We reviewed the medical records of all patients ≤16 years with uveitis referred to Massachusetts Eye Research and Surgery Institution from March 2005 to July 2016. Results: Of 286 included children, 62.24% were female. Mean age of onset was 8.4 years. The uveitis was mainly anterior (61.9%), recurrent (68.53%), bilateral (81.82%), and noninfectious (96.5%). Idiopathic cases accounted for 51.4%. The most frequent systemic association was juvenile idiopathic arthritis (34.96%). The majority of patients (78.32%) experienced complications. All patients, except one, needed systemic therapy. Conclusion: Pediatric uveitis is challenging to diagnose and manage, with frequent and potentially severe complications. Most cases were bilateral, recurrent, and idiopathic. Prompt referral to uveitis-specialized centers and an appropriate systemic therapy are mandatory for good visual outcomes.


Subject(s)
Referral and Consultation , Tertiary Care Centers , Uveitis/epidemiology , Visual Acuity , Child , Female , Follow-Up Studies , Humans , Incidence , Male , Retrospective Studies , United States/epidemiology , Uveitis/diagnosis
11.
J Diabetes Res ; 2018: 7163652, 2018.
Article in English | MEDLINE | ID: mdl-30250850

ABSTRACT

The haptoglobin (Hp) genotype (1-1 and 2-2) is a major determinant of nephropathy progression in diabetes mellitus patients. Hp 2-2 diabetic mice have impaired Hb clearance and increased iron deposits and oxidative stress in the proximal tubules (PCT), leading to increased renal injury. However, the precise mechanism of the PCT injury in diabetic nephropathy (DN) remains elusive. In the kidney, 1,25(OH)2D3 suppresses the inflammatory response to renal tubular injury and requires normal renal expression of the α-klotho protein. In this study, we set out to test the hypothesis that the increased renal iron deposits in the PCT of Hp 2-2 DN affect the α-klotho-vitamin D receptor (VDR) axis and thereby exacerbates the PCT injury generated by the iron deposits. Immunohistochemical analysis of human and mouse kidney biopsies along with western blot analysis showed that the increased iron deposits in the PCT of the Hp 2-2 genotype were accompanied with significantly decreased α-klotho and VDR renal expression but significantly increased 1-α-hydroxylase renal expression. In conclusion, the iron-klotho-VDR axis is a major player in the mechanism contributing to iron-mediated PCT injury in diabetic Hp 2-2 mice and patients. Targeting this axis may open the way for new ideas regarding the pathogenesis and treatment of DN.


Subject(s)
Diabetic Nephropathies/metabolism , Glucuronidase/metabolism , Haptoglobins/genetics , Iron/metabolism , Kidney Tubules, Proximal/metabolism , Receptors, Calcitriol/metabolism , Renal Insufficiency, Chronic/metabolism , Adult , Aged , Animals , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Diabetic Nephropathies/genetics , Diabetic Nephropathies/pathology , Disease Models, Animal , Female , Genotype , Haptoglobins/metabolism , Humans , Kidney Tubules, Proximal/pathology , Klotho Proteins , Male , Mice , Middle Aged , Oxidative Stress , Renal Insufficiency, Chronic/pathology , Young Adult
12.
Harefuah ; 155(7): 439-442, 2016 Jul.
Article in Hebrew | MEDLINE | ID: mdl-28514126

ABSTRACT

INTRODUCTION: The antioxidant protein haptoglobin (Hp) plays a major role in the development of diabetic complications such as diabetic nephropathy and retinopathy. In humans, two alleles of Hp were identified: 1 and 2 with three possible genotypes: 1-1, 2-1, and 2-2. The Hp protein products differ in their biochemical and biophysical properties, such as their antioxidant capacity. The Hp1 protein is superior to the Hp2 protein in binding to free hemoglobin and neutralizing its oxidative potential and the accompanying renal and retinal injury. Hence, diabetic patients with different Hp phenotypes have variable susceptibility to developing diabetic nephropathy and retinopathy. In diabetes, the kidney and the retinal injury progress gradually over time. Thus, understanding the factors that mediate the aggravation and progression of these complications is of critical importance. One of the latest hypotheses regarding the involvement of haptoglobin in the development of diabetic complications is its contribution to impaired vitamin D activation in the kidney. Over the last few years, great efforts were made in the field to explore this notion and decrypt the mechanism behind it. The goal in this area is that the research findings will be translated into clinical practice and lead to the development of a pharmacogenomics clinical approach that will deal with diabetic complications by selective administration of vitamin D according to the Hp genotype.


Subject(s)
Diabetic Nephropathies/genetics , Diabetic Retinopathy/genetics , Haptoglobins/genetics , Haptoglobins/physiology , Antioxidants , Diabetic Nephropathies/metabolism , Diabetic Retinopathy/metabolism , Genotype , Humans , Polymorphism, Genetic
13.
J Diabetes Res ; 2015: 613860, 2015.
Article in English | MEDLINE | ID: mdl-26171400

ABSTRACT

Elevated systolic pulmonary artery pressure (s-PAP, ≥35 mmHg) serves as an independent predictor of mortality in hemodialysis (HD) and diabetic (DM) patients. A polymorphism in the antioxidant Haptoglobin (Hp) gene has been shown to regulate the bioavailability of nitric oxide (NO), a major mediator of pulmonary vascular tone. We therefore set out to test the hypothesis that the Hp polymorphism may be a determinant of developing elevated s-PAP specifically in the DM state due to a decreased bioavailability of NO. To test our hypothesis we Hp typed and performed transthoracic echocardiography on a series of HD patients and stratified them into elevated and normal s-PAP groups and then evaluated whether there was a significant association between the Hp type, elevated s-PAP, and decreased NO bioavailability as defined by low plasma nitrite. We found a statistically significant interaction between the Hp type and DM on the prevalence of elevated s-PAP and lower mean nitrite levels with the combination of elevated s-PAP and low nitrite levels being significantly more prevalent in Hp 2-2 DM individuals. We conclude that the Hp 2 type is associated with elevated s-PAP levels and low plasma nitrite levels in HD patients specifically in the DM state.


Subject(s)
Arterial Pressure , Diabetes Mellitus/metabolism , Haptoglobins/genetics , Hypertension, Pulmonary/metabolism , Kidney Failure, Chronic/metabolism , Nitric Oxide/metabolism , Nitrites/metabolism , Pulmonary Artery/diagnostic imaging , Adult , Aged , Aged, 80 and over , Case-Control Studies , Cross-Sectional Studies , Diabetes Complications , Echocardiography , Female , Humans , Hypertension, Pulmonary/genetics , Kidney Failure, Chronic/therapy , Logistic Models , Male , Middle Aged , Phenotype , Polymorphism, Genetic , Pulmonary Wedge Pressure , Renal Dialysis
14.
World J Nephrol ; 2(4): 111-24, 2013 Nov 06.
Article in English | MEDLINE | ID: mdl-24255894

ABSTRACT

Diabetes mellitus (DM) is associated with increased oxidative stress due to elevated glucose levels in the plasma. Glucose promotes glycosylation of both plasma and cellular proteins with increased risk for vascular events. Diabetic patients suffer from a higher incidence of cardiovascular complications such as diabetic nephropathy. Haptoglobin (Hp) is an antioxidant plasma protein which binds free hemoglobin, thus preventing heme-iron mediated oxidation. Two alleles exist at the Hp gene locus (1 and 2) encoding three possible Hp genotypes that differ in their antioxidant ability, and may respond differently to vitamin E treatment. Several clinical studies to have shown that Hp 1-1 genotype is a superior antioxidant to the Hp 2-2 genotype and Hp 2-2 genotype is associated with a higher incidence of cardiovascular disease. Vitamin E was found to have beneficial effect in patient and mice with Hp 2-2 genotype. In this review we have summarized the results of our studies in patients with diabetic nephropathy treated with vitamin E and in diabetic mice with different haptoglobin genotypes.

15.
Diabetes Res Clin Pract ; 100(3): 289-97, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23490597

ABSTRACT

Diabetic nephropathy (DN) is the leading cause of end stage renal disease and dialysis worldwide. Despite aggressive treatment, the number of patients on hemodialysis due to type 1 and type 2 diabetes mellitus is increasing annually. The lack of reliable animal models that mimic human disease has delayed the identification of specific factors that cause or predict DN. Different investigators around the world are testing different murine models. Validation criteria for early and advanced DN, phenotypic methods, background strain have recently been developed. Establishment of an authentic mouse model of DN will undoubtedly facilitate the understanding of the underlying genetic mechanisms that contribute to the development of DN and to study new treatments. Here we describe the characteristics of our new mouse model with type 1 diabetes mellitus and different haptoglobin genotypes that can mimic human DN.


Subject(s)
Diabetic Nephropathies/pathology , Albuminuria/pathology , Animals , Diabetes Mellitus, Type 1/pathology , Diabetes Mellitus, Type 2/pathology , Disease Models, Animal , Glomerular Filtration Rate/physiology , Mice
16.
Free Radic Biol Med ; 53(4): 779-86, 2012 Aug 15.
Article in English | MEDLINE | ID: mdl-22749805

ABSTRACT

The haptoglobin (Hp) genotype is a major determinant of progression of nephropathy in individuals with diabetes mellitus (DM). The major function of the Hp protein is to bind and modulate the fate of extracorpuscular hemoglobin and its iron cargo. We have previously demonstrated an interaction between the Hp genotype and the DM on the accumulation of iron in renal proximal tubule cells. The primary objective of this study was to determine the intracellular localization of this iron in the proximal tubule cell and to assess its potential toxicity. Transmission electron microscopy demonstrated a marked accumulation of electron-dense deposits in the lysosomes of proximal tubules cells in Hp 2-2 DM mice. Energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy were used to perform elemental analysis of these deposits and demonstrated that these deposits were iron rich. These deposits were associated with lysosomal membrane lipid peroxidation and loss of lysosomal membrane integrity. Vitamin E administration to Hp 2-2 DM mice resulted in a significant decrease in both intralysosomal iron-induced oxidation and lysosomal destabilization. Iron-induced renal tubular injury may play a major role in the development of diabetic nephropathy and may be a target for slowing the progression of renal disease.


Subject(s)
Diabetes Mellitus, Experimental/complications , Diabetic Nephropathies/genetics , Haptoglobins/genetics , Kidney Tubules, Proximal/pathology , Lysosomes/pathology , Animals , Antioxidants/pharmacology , Antioxidants/therapeutic use , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/metabolism , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/metabolism , Genotype , Intracellular Membranes , Iron/metabolism , Kidney Tubules, Proximal/drug effects , Kidney Tubules, Proximal/metabolism , Lipid Peroxidation/drug effects , Lysosomes/drug effects , Lysosomes/metabolism , Mice , Mice, Inbred C57BL , Oxidation-Reduction , Oxidative Stress , Vitamin E/pharmacology , Vitamin E/therapeutic use , beta-N-Acetylhexosaminidases/metabolism
17.
Endocrine ; 41(1): 53-7, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22169961

ABSTRACT

Gitelman's syndrome (GS), also known as familial hypokalemic hypomagnesemia, is a rare autosomal recessive hereditary salt-losing tubulopathy, characterized by hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria, which is usually caused by mutations in the SLC12A3 gene encoding the thiazide-sensitive sodium chloride contrasporter. Because 18-40% of suspected GS patients carry only one SLC12A3 mutant allele, large genomic rearrangements must account for unidentified mutations. The clinical manifestations of GS are highly variable in terms of age at presentation, severity of symptoms, and biochemical abnormalities. Molecular analysis in our sibling's patients revealed compound heterozygous mutations in the coding region of SLC12A3 as underlying their disease. Such compound heterozygosity can result in disease phenotype for such loss of function mutations in the absence of homozygosis through consanguineous inheritance of mutant alleles, identical by descent. Missense mutations account for approximately 70% of the mutations in GS, and there is a predisposition to large rearrangements caused by the presence of repeated sequences within the SLC12A3. We report two adult male siblings of Jewish origin with late onset GS, who presented in their fifth decade of life with muscle weakness, hypokalemia, hypomagnesaemia, and metabolic alkalosis. Rapid clinical and biochemical improvement was achieved by replacement therapy with potassium and magnesium.


Subject(s)
Gitelman Syndrome/genetics , Gitelman Syndrome/physiopathology , Mutation/genetics , Receptors, Drug/genetics , Symporters/genetics , Adult , Amino Acid Sequence , Animals , Gitelman Syndrome/drug therapy , Humans , Magnesium/therapeutic use , Male , Middle Aged , Molecular Sequence Data , Potassium/therapeutic use , Solute Carrier Family 12, Member 3 , Treatment Outcome
18.
Endocrine ; 38(2): 303-8, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20972727

ABSTRACT

In pre-eclampsia, poor placentation causes both oxidative and endoplasmic reticulum stress of the placenta. The anti-oxidative protein Haptoglobin has three phenotypes: 1-1, 1-2, and 2-2. Haptoglobin 1-1 is a more potent antioxidant. Our objective was to determine whether haptoglobin 1-1 was less common in women with preeclampsia which is a disease with an oxidatives-stress component, compared to the healthy population. Haptoglobin phenotype was compared in 240 healthy and 120 preeclamptic gravida in a case-control study. Statistical analysis was performed using Chi square test. The prevalence of haptoglobin 1-1 was 13% among healthy women and 6% among preeclamptic women (P=0.049). Secondary analysis was also performed. The prevalence of haptoglobin 1-1 is higher in healthy compared to preeclamptic subjects, a finding compatible with a protective role. Haptoglobin 1-1 might have a protective role in preeclampsia. Further work is needed with more Hp 1-1 subjects before we can conclude on the possible use of Haptoglobin phenotype to assess the risk of preeclampsia.


Subject(s)
Haptoglobins/metabolism , Oxidative Stress/physiology , Pre-Eclampsia/epidemiology , Pre-Eclampsia/metabolism , Adult , Case-Control Studies , Electrophoresis, Polyacrylamide Gel , Female , Humans , Phenotype , Pregnancy , Prevalence , Risk Factors , Young Adult
19.
Am J Physiol Renal Physiol ; 296(4): F830-8, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19176700

ABSTRACT

Polymorphic loci regulating oxidative stress are potential susceptibility genes for diabetic nephropathy (DN). Haptoglobin (Hp) is an antioxidant protein which serves to protect against oxidative stress induced by extracorpuscular hemoglobin. There are two alleles at the Hp locus, 1 and 2. The Hp 1 protein is a superior antioxidant to the Hp 2 protein. The Hp 2 allele has been associated with increased prevalence of DN and appears to be associated with a more rapid progression to end-stage renal disease. We sought to recapitulate this association between Hp genotype and DN in mice genetically modified at the Hp locus. We assessed morphometric, histologic, and functional parameters involved in the development and progression of DN in mice with diabetes mellitus (DM) with either the Hp 2-2 or Hp 1-1 genotype. Morphometric analysis demonstrated that glomerular and proximal tubular hypertrophy were significantly increased in Hp 2-2 DM mice. Histological analysis demonstrated that Hp 2-2 DM mice had significantly more collagen type IV, smooth muscle actin, and increased renal iron deposition. Studies of renal function demonstrated creatinine clearance time and albuminuria were increased in Hp 2-2 DM mice. Vitamin E provided significant protection against the development of functional and histological features characteristic of DN to Hp 2-2 DM but not to Hp 1-1 DM mice. These studies serve to strengthen the association between the Hp 2-2 genotype and diabetic renal disease and suggest a pharmacogenomic interaction may exist between the Hp genotype and vitamin E.


Subject(s)
Antioxidants/pharmacology , Diabetes Mellitus, Experimental/drug therapy , Diabetic Nephropathies/prevention & control , Haptoglobins/genetics , Kidney/drug effects , Oxidative Stress/drug effects , Vitamin E/pharmacology , Actins/metabolism , Albuminuria/metabolism , Albuminuria/prevention & control , Animals , Collagen Type IV/metabolism , Creatinine/blood , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Experimental/physiopathology , Diabetic Nephropathies/genetics , Diabetic Nephropathies/pathology , Diabetic Nephropathies/physiopathology , Genotype , Glomerular Filtration Rate/drug effects , Haptoglobins/metabolism , Hypertrophy , Iron/metabolism , Kidney/metabolism , Kidney/pathology , Kidney/physiopathology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Oxidative Stress/genetics , Phenotype
20.
Am J Physiol Renal Physiol ; 294(3): F628-37, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18094029

ABSTRACT

Nephrotic syndrome (NS) is a clinical state characterized by massive proteinuria and edema. It is believed that nephrin and podocin are involved in the development of proteinuria. The proteinuria and effects of eplerenone alone or combined with enalapril on nephrin/podocin abundance in rats with NS have not yet been studied. Therefore, the present study was designed to examine the early (beginning 2 days before NS induction) and late (beginning 2 wk after NS induction) effects of eplerenone and enalapril, alone or combined, on proteinuria and nephrin/podocin abundance in rats with adriamycin-induced NS. Adriamycin caused a significant increase in daily protein excretion (U(pr)V; from 26.96 +/- 3.43 to 958.57 +/- 56.7 mg/day, P < 0.001) and cumulative proteinuria [from 900.33 +/- 135.5 to 22,490.62 +/- 931.26 mg (P < 0.001)] during 6 wk. Early treatment with enalapril significantly decreased U(pr)V from 958.6 +/- 56.7 to 600.31 +/- 65.13 mg/day (P < 0.001) and cumulative proteinuria to 12,842.37 +/- 1,798.17 mg/6 wk (P < 0.001). Similarly, early treatment with eplerenone produced a profound antiproteinuric effect: U(pr)V decreased from 958.57 +/- 56.7 to 593.38 +/- 21.83 mg/day, P < 0.001, and cumulative proteinuria to 16,601.84 +/- 1,334.31 mg/6 wk; P < 0.001. An additive effect was obtained when enalapril and eplerenone were combined: U(pr)V decreased from 958.57 +/- 56.69 to 424.17 +/- 38.54 mg/day, P < 0.001, and cumulative protein excretion declined to 10,252.88 +/- 1,011.3 mg/6 wk, P < 0.001. These antiproteinuric effects were associated with substantial preservation of glomerular nephrin and podocin. In contrast, late treatment with either enalapril or eplerenone alone or combined mildly decreased U(pr)V and cumulative proteinuria. Thus pretreatment with eplerenone or enalapril is effective in reducing daily and cumulative protein excretion and preservation of nephrin/podocin. More profound antiproteinuric effects were obtained when enalapril and eplerenone were combined.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Enalapril/therapeutic use , Mineralocorticoid Receptor Antagonists/therapeutic use , Nephrotic Syndrome/drug therapy , Proteinuria/drug therapy , Spironolactone/analogs & derivatives , Albuminuria/drug therapy , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Blood Pressure/drug effects , Blood Urea Nitrogen , Drug Synergism , Electrolytes/blood , Enalapril/pharmacology , Eplerenone , Immunohistochemistry , Lipids/blood , Male , Mineralocorticoid Receptor Antagonists/pharmacology , Rats , Rats, Sprague-Dawley , Spironolactone/pharmacology , Spironolactone/therapeutic use
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