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Brkić BM, Rovčanin B, Stojanović M, Srebro D, Vučković S, Savić Vujović K. Chloroquine Attenuates Oxidative Stress in Gentamicin-Induced Nephrotoxicity in Rats. Dose Response 2022; 20:15593258221119871. [PMID: 36003319 PMCID: PMC9393693 DOI: 10.1177/15593258221119871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/18/2022] [Accepted: 07/24/2022] [Indexed: 11/25/2022]
Abstract
The wider application of gentamicin is limited by potential adverse effects
(nephrotoxicity and ototoxicity). The goal of our study was to investigate the effects of
chloroquine on biochemical and oxidative stress parameters in gentamicin-induced
nephrotoxicity in rats. Animals were randomly divided into 1 of 5 groups. First was Sham
group (0.9% NaCl) (n = 8); second group received gentamicin (n = 8); while third (n = 8),
fourth (n = 8) and fifth group (n = 8) received gentamicin and chloroquine in a dose of
0.3, 1 and 3 mg/kg, respectively. The urea and creatinine levels were significantly lower
in chloroquine treated groups in doses of 0.3 mg/kg and 1 mg/kg (P <
0.001). Total oxidant status and the oxidative stress index showed significantly lower
values in all chloroquine treated groups (P < 0.001;
P < 0.005). Malondialdehyde was lower in chloroquine treatment in
doses of 0.3 mg/kg (P < 0.005) and 3 mg/kg (P <
0.05). Chloroquine treatment markedly reduced the level of superoxide dismutase in doses
of 1 mg/kg (P < 0.01) and 3 mg/kg (P < 0.05). Our
study showed that chloroquine attenuates gentamicin-induced nephrotoxicity in rats
regarding biochemical and oxidative stress parameters.
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Affiliation(s)
- Branislava Medić Brkić
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Branislav Rovčanin
- Centre for Endocrine Surgery, Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Marko Stojanović
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Dragana Srebro
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Sonja Vučković
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Katarina Savić Vujović
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
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Systemic toxicity of chloroquine and hydroxychloroquine: prevalence, mechanisms, risk factors, prognostic and screening possibilities. Rheumatol Int 2021; 41:1189-1202. [PMID: 33893862 PMCID: PMC8064887 DOI: 10.1007/s00296-021-04868-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 04/13/2021] [Indexed: 02/07/2023]
Abstract
Chloroquine (CQ) and its hydroxylated analog, hydroxychloroquine (HCQ), are 4-aminoquinoline initially used as an antimalarial treatment. CQ and HCQ (4-aminoquinoline, 4-AQ) are today used in rheumatology, especially to treat rheumatoid arthritis and systemic lupus erythematosus. Their mechanism of action revolves around a singular triptych: 4-AQ acts as alkalizing agents, ionized amphiphilic molecules, and by binding to numerous targets. 4-AQ have so pleiotropic and original mechanisms of action, providing them an effect at the heart of the regulation of several physiological functions. However, this broad spectrum of action is also at the origin of various and original side effects, notably a remarkable chronic systemic toxicity. We describe here the 4-AQ-induced lesions on the eye, the heart, muscle, the nerves, the inner ear, and the kidney. We also describe their prevalence, their pathophysiological mechanisms, their risk factors, their potential severity, and the means to detect them early. Most of these side effects are reversible if treatment is stopped promptly. This 4-AQ-induced toxicity must be known to prescribing physicians, to closely monitor its appearance and stop treatment in time if necessary.
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Raza SH, Elshaikh E, Ahmed MH, Raja M. Calcified stone in intestinal blind loop after 60 years of surgical treatment of complex jejunal atresia: an attempt to understand an enigma. BMJ Case Rep 2020; 13:13/1/e231992. [PMID: 31919061 DOI: 10.1136/bcr-2019-231992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A 60-year-old woman was presented in emergency department with abdominal pain and vomiting for 1 day. She was known to have seropositive rheumatoid arthritis. Importantly, she was treated surgically for complex jejunal atresia and duplication surgery, when she was 6 days old. CT scan showed intestinal obstruction secondary to intussception. Patient had lapartomy and operative findings revealed side-to-side anastomosis with gut duplication 10 cm distal to duodenal jejunum junction (due to her previous surgery during infancy). Redundant part of the loop dilated up to 300 mL with large hard stone (4×3.5 cm) was excised. Patient recovered well postoperatively and was discharged to go home. To our knowledge, this is the first case report to show formation of large stone 60 years after surgical treatment of complex jejunal atresia and duplication surgery in infancy.
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Affiliation(s)
- Syed H Raza
- Department of Surgery, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes, Buckinghamshire, UK
| | - Elamin Elshaikh
- Department of Surgery, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes, Buckinghamshire, UK
| | - Mohamed H Ahmed
- Department of Medicine and HIV Metabolic Clinic, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes, Buckinghamshire, UK
| | - Mazhar Raja
- Department of Surgery, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes, Buckinghamshire, UK
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Violacein Treatment Modulates Acute and Chronic Inflammation through the Suppression of Cytokine Production and Induction of Regulatory T Cells. PLoS One 2015; 10:e0125409. [PMID: 25938431 PMCID: PMC4418714 DOI: 10.1371/journal.pone.0125409] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 03/23/2015] [Indexed: 12/20/2022] Open
Abstract
Inflammation is a necessary process to control infection. However, exacerbated inflammation, acute or chronic, promotes deleterious effects in the organism. Violacein (viola), a quorum sensing metabolite from the Gram-negative bacterium Chromobacterium violaceum, has been shown to protect mice from malaria and to have beneficial effects on tumors. However, it is not known whether this drug possesses anti-inflammatory activity. In this study, we investigated whether viola administration is able to reduce acute and chronic autoimmune inflammation. For that purpose, C57BL/6 mice were intraperitoneally injected with 1 μg of LPS and were treated with viola (3.5mg/kg) via i.p. at the same time-point. Three hours later, the levels of inflammatory cytokines in the sera and phenotypical characterization of leukocytes were determined. Mice treated with viola presented a significant reduction in the production of inflammatory cytokines compared with untreated mice. Interestingly, although viola is a compound derived from bacteria, it did not induce inflammation upon administration to naïve mice. To test whether viola would protect mice from an autoimmune inflammation, Experimental Autoimmune Encephalomyelitis (EAE)-inflicted mice were given viola i.p. at disease onset, at the 10th day from immunization. Viola-treated mice developed mild EAE disease in contrast with placebo-treated mice. The frequencies of dendritic cells and macrophages were unaltered in EAE mice treated with viola. However, the sole administration of viola augmented the levels of splenic regulatory T cells (CD4+Foxp3+). We also found that adoptive transfer of viola-elicited regulatory T cells significantly reduced EAE. Our study shows, for the first time, that violacein is able to modulate acute and chronic inflammation. Amelioration relied in suppression of cytokine production (in acute inflammation) and stimulation of regulatory T cells (in chronic inflammation). New studies must be conducted in order to assess the possible use of viola in therapeutic approaches in human autoimmune diseases.
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Verinaud L, Issayama LK, Zanucoli F, de Carvalho AC, da Costa TA, Di Gangi R, Bonfanti AP, Ferreira IT, de Oliveira ALR, Machado DRS, Thomé R. Nitric oxide plays a key role in the suppressive activity of tolerogenic dendritic cells. Cell Mol Immunol 2014; 12:384-6. [PMID: 25308751 DOI: 10.1038/cmi.2014.94] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 09/04/2014] [Accepted: 09/04/2014] [Indexed: 02/04/2023] Open
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Abstract
The 4-aminoquinolines are weak bases that are completely absorbed from the gastrointestinal tract, sequestered in peripheral tissues, metabolized in the liver to pharmacologically active by-products, and excreted via the kidneys and the feces. The parent drugs and metabolites are excreted with a half-life of elimination of approximately 40 days. However, slow release from sequestered stores of the drugs means that after discontinuation, they continue to be released into the plasma for years. Correct dosing is based on the ideal body weight of the patient, which depends on height. The 4AQs diminish autoimmunity without compromising immunity to infections.
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Affiliation(s)
- David J. Browning
- grid.490463.cCharlotte Eye Ear Nose & Throat Associates, Charlotte, NC USA
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7
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Todorovic Z, Medic B, Basta-Jovanovic G, Radojevic Skodric S, Stojanovic R, Rovcanin B, Prostran M. Acute pretreatment with chloroquine attenuates renal I/R injury in rats. PLoS One 2014; 9:e92673. [PMID: 24681567 PMCID: PMC3969327 DOI: 10.1371/journal.pone.0092673] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 02/25/2014] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Acute kidney injury (AKI) still remains an unresolved problem in pharmacotherapy and renal inflammation is a major factor in its development. Chloroquine, a well-known antimalarial drug, posses pleitropic effects as well: antiinflammatory, anticoagulant and vascular actions. The effects of chloroquine on renal function may involve significant increase in urine flow rate, glomerular filtration rate and sodium excretion, as well as stimulation of nitric oxide synthase. However, its role in experimental models of renal I/R injury is unknown. We aimed to analyze the acute effects of a single-dose intravenous chloroquine administered at three different times in the experimental model of I/R injury in rat. METHODS Rats were subjected to bilateral renal ischemia (45 min) followed by reperfusion with saline lasting 4 hours. Chloroquine was administered in doses of 0.3 mg/kg i.v. and 3 mg/kg i.v. 30 min before ischemia, 30 min before reperfusion and 5 min before reperfusion. Selected a hemodynamic, biochemical and morphological parameters were followed in the Sham-operated animals and rats subjected to I/R injury and pretreated with saline or chloroquine. RESULTS Chloroquine (0.3 and 3 mg/kg, i.v.) protected the I/R injured kidney in an U-shaped manner. Both doses were protective regarding biochemical and histological markers of the I/R injury (serum urea, creatinine and fractional excretion of sodium, as well as total histological score, tubular necrosis score and KIM-1 staining score) (P<0.05 vs. corresponding controls, i.e. rats subjected to I/R injury and treated with saline only). The protective effects of the lower dose of chloroquine were more profound. Time-related differences between pretreatments were not observed (P>0.05, all). CONCLUSION Our study shows for the first time that a single dose of chloroquine (0.3 mg/kg i.v.) could afford significant protection of the injured rat kidney.
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Affiliation(s)
- Zoran Todorovic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Branislava Medic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | | | | | - Radan Stojanovic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Branislav Rovcanin
- Department of Human Genetics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Milica Prostran
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
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8
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Dendritic cells treated with chloroquine modulate experimental autoimmune encephalomyelitis. Immunol Cell Biol 2013; 92:124-32. [PMID: 24217811 DOI: 10.1038/icb.2013.73] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 10/03/2013] [Accepted: 10/11/2013] [Indexed: 12/22/2022]
Abstract
Chloroquine (CQ), an antimalarial drug, has been shown to modulate the immune system and reduce the severity of experimental autoimmune encephalomyelitis (EAE). The mechanisms of disease suppression are dependent on regulatory T cell induction, although Tregs-independent mechanisms exist. We aimed to evaluate whether CQ is capable to modulate bone marrow-derived dendritic cells (DCs) both phenotypically and functionally as well as whether transfer of CQ-modulated DCs reduces EAE course. Our results show that CQ-treated DCs presented altered ultrastructure morphology and lower expression of molecules involved in antigen presentation. Consequently, T cell proliferation was diminished in coculture experiments. When transferred into EAE mice, DC-CQ was able to reduce the clinical manifestation of the disease through the modulation of the immune response against neuroantigens. The data presented herein indicate that chloroquine-mediated modulation of the immune system is achieved by a direct effect on DCs and that DC-CQ adoptive transfer may be a promising approach for avoiding drug toxicity.
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Carnovale C, Perrone V, Borsadoli C, Mambrini A, Speziali A, Froldi G, Antoniazzi S, Magistro L, Clementi E, Radice S. A case of urinary incontinence by hydroxychloroquine in a geriatric patient. J Clin Pharm Ther 2012. [DOI: 10.1111/jcpt.12024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. Carnovale
- Scientific Institute; IRCCS Eugenio Medea; Lecco Italy
| | - V. Perrone
- Unit of Clinical Pharmacology; Department of Biomedical and Clinical Sciences; University Hospital ‘Luigi Sacco’; Università di Milano; Milan Italy
| | - C. Borsadoli
- Pharmaceutical Service; Azienda Sanitaria Locale di Mantova; Mantua Italy
| | - A. Mambrini
- Physician, Azienda Sanitaria Locale di Mantova; Mantua Italy
| | - A. Speziali
- Pharmaceutical Service; Azienda Sanitaria Locale di Mantova; Mantua Italy
| | - G. Froldi
- Pharmaceutical Service; Azienda Sanitaria Locale di Mantova; Mantua Italy
| | - S. Antoniazzi
- Unit of Clinical Pharmacology; Department of Biomedical and Clinical Sciences; University Hospital ‘Luigi Sacco’; Università di Milano; Milan Italy
| | - L. Magistro
- Postgraduate School of Clinical Pharmacology; Department of Pharmacology “E. Trabucchi”; Università di Milano, Milan Italy
| | - E. Clementi
- Scientific Institute; IRCCS Eugenio Medea; Lecco Italy
- Unit of Clinical Pharmacology; Department of Biomedical and Clinical Sciences; University Hospital ‘Luigi Sacco’; Università di Milano; Milan Italy
| | - S. Radice
- Unit of Clinical Pharmacology; Department of Biomedical and Clinical Sciences; University Hospital ‘Luigi Sacco’; Università di Milano; Milan Italy
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von Bergen TN, Blount MA. Chronic use of chloroquine disrupts the urine concentration mechanism by lowering cAMP levels in the inner medulla. Am J Physiol Renal Physiol 2012; 303:F900-5. [PMID: 22791344 PMCID: PMC3468520 DOI: 10.1152/ajprenal.00547.2011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Accepted: 07/10/2012] [Indexed: 11/22/2022] Open
Abstract
Chloroquine, a widely used anti-malaria drug, has gained popularity for the treatment of rheumatoid arthritis, systemic lupus erythematosus (SLE), and human immunodeficiency virus (HIV). Unfortunately, chloroquine may also negatively impact renal function for patients whose fluid and electrolyte homeostasis is already compromised by diseases. Chronic administration of chloroquine also results in polyuria, which may be explained by suppression of the antidiuretic response of vasopressin. Several of the transporters responsible for concentrating urine are vasopressin-sensitive including the urea transporters UT-A1 and UT-A3, the water channel aquaporin-2 (AQP2), and the Na(+)-K(+)-2Cl(-) cotransporter (NKCC2). To examine the effect of chloroquine on these transporters, Sprague-Dawley rats received daily subcutaneous injections of 80 mg·kg(-1)·day(-1) of chloroquine for 4 days. Twenty-four hour urine output was twofold higher, and urine osmolality was decreased by twofold in chloroquine-treated rats compared with controls. Urine analysis of treated rats detected the presence chloroquine as well as decreased urine urea and cAMP levels compared with control rats. Western blot analysis showed a downregulation of AQP2 and NKCC2 transporters; however, UT-A1 and UT-A3 abundances were unaffected by chloroquine treatment. Immunohistochemistry showed a marked reduction of UT-A1 and AQP2 in the apical membrane in inner medullary collecting ducts of chloroquine-treated rats. In conclusion, chloroquine-induced polyuria likely occurs as a result of lowered cAMP production. These findings suggest that chronic chloroquine treatment would exacerbate the already compromised fluid homeostasis observed in diseases like chronic kidney disease.
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Affiliation(s)
- Tobias N von Bergen
- Department of Medicine, Renal Division, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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11
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Alwasel SH, Ashton N. Segmental sodium reabsorption by the renal tubule in prenatally programmed hypertension in the rat. Pediatr Nephrol 2012; 27:285-93. [PMID: 21863227 DOI: 10.1007/s00467-011-1976-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 07/05/2011] [Accepted: 07/05/2011] [Indexed: 10/17/2022]
Abstract
Hypertension and renal dysfunction can be programmed in the rat by prenatal exposure to a low-protein (LP) diet. Expression of the renal thick ascending limb (TAL) sodium transporter NKCC2 is up-regulated, which has been predicted to result in greater sodium reabsorption. However, we have shown that LP rats excrete more not less sodium. The aim of this study was to determine whether the increased abundance of sodium:potassium:chloride (Na(+):K(+):2Cl(-)) co-transporter (NKCC2) leads to enhanced sodium uptake by the TAL. Pregnant Wistar rats were fed a control (18%) or LP (9%) diet. Amiloride (AM), bendroflumethiazide (BF), and furosemide (FUR) were administered acutely to male offspring at 4 weeks of age. Fractional excretion of sodium (FE(Na)) was significantly greater in vehicle-infused LP rats (3.0 ± 0.3%) compared with controls (1.7 ± 0.5, P < 0.01). FE(Na) by the LP proximal tubule did not differ from controls, whereas FE(Na) by the distal tubule was significantly greater (P < 0.01). These differences were abolished by the administration of AM + BF (equivalent to the outflow from the TAL) and AM + BF + FUR (equivalent to the outflow from the proximal tubule), suggesting that the increase in NKCC2 expression was not functional. However, during acute salt loading, the LP rat pressure natriuresis curve was shifted rightward, implying that raised systemic blood pressure is required to match urinary sodium excretion with dietary intake. These data suggest that renal sodium handling is impaired in the LP rat but that this is not due to increased NKCC2 expression.
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Affiliation(s)
- Saleh H Alwasel
- Fetal Programming of Diseases Research Chair, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia.
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12
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Abstract
Prenatally programmed hypertension induced by maternal protein restriction is associated with increased expression of the renal tubular Na+/K+/2Cl- co-transporter (NKCC2) and the Na+/Cl- co-transporter (NCC). This has led to the suggestion that renal Na+ retention contributes to the development of hypertension in the LP rat (offspring exposed to a maternal low-protein diet in utero). However, this hypothesis has not been tested in vivo. Renal clearance measurements in hypertensive 4-week-old male and female LP rats showed that, although the glomerular filtration rate remained unaltered, urine flow (P<0.01) and urinary Na+ excretion rates (1.6+/-0.3 and 3.0+/-0.4 mumol.min-1.100 g-1 of body weight in control male and LP male respectively; P<0.001) were increased. Na+ excretion was positively correlated with mean arterial pressure in both males (P<0.01) and females (P<0.05), but neither the slope nor the intercept differed between control and LP rats. Fractional excretion of Na+ was increased in male (1.5+/-0.2 and 3.0+/-0.5% in control and LP rats respectively; P<0.001) and female LP rats, implying reduced tubular reabsorption of Na+. Western blotting and quantitative PCR showed that NKCC2 expression was increased, whereas NCC mRNA was not up-regulated. Na+/K+ ATPase alpha1 subunit expression did not differ from controls; however, there was a significant reduction in whole kidney pump activity (23.4+/-1.8 and 17.7+/-1.2 nmol of phosphate.mug-1 of protein.h-1 in control male and male LP rats respectively; P<0.001); immunohistochemistry showed that the alpha1 subunit was virtually absent from the inner medulla. The greater Na+ excretion of LP rats can be explained, in part, by a pressure-natriuresis mechanism; however, the loss of the Na+/K+ ATPase alpha1 subunit from the inner medulla and up-regulation of NKCC2 suggests that altered renal Na+ handling is also programmed prenatally.
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Yasuda H, Leelahavanichkul A, Tsunoda S, Dear JW, Takahashi Y, Ito S, Hu X, Zhou H, Doi K, Childs R, Klinman DM, Yuen PST, Star RA. Chloroquine and inhibition of Toll-like receptor 9 protect from sepsis-induced acute kidney injury. Am J Physiol Renal Physiol 2008; 294:F1050-8. [PMID: 18305095 DOI: 10.1152/ajprenal.00461.2007] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mortality from sepsis has remained high despite recent advances in supportive and targeted therapies. Toll-like receptors (TLRs) sense bacterial products and stimulate pathogenic innate immune responses. Mice deficient in the common adapter protein MyD88, downstream from most TLRs, have reduced mortality and acute kidney injury (AKI) from polymicrobial sepsis. However, the identity of the TLR(s) responsible for the host response to polymicrobial sepsis is unknown. Here, we show that chloroquine, an inhibitor of endocytic TLRs (TLR3, 7, 8, 9), improves sepsis-induced mortality and AKI in a clinically relevant polymicrobial sepsis mouse model, even when administered 6 h after the septic insult. Chloroquine administration attenuated the decline in renal function, splenic apoptosis, serum markers of damage to other organs, and prototypical serum pro- and anti-inflammatory cytokines TNF-alpha and IL-10. An oligodeoxynucleotide inhibitor (H154) of TLR9 and TLR9-deficient mice mirror the actions of chloroquine in all functional parameters that we tested. In addition, chloroquine decreased TLR9 protein abundance in spleen, further suggesting that TLR9 signaling may be a major target for the protective actions of chloroquine. Our findings indicate that chloroquine improves survival by inhibiting multiple pathways leading to polymicrobial sepsis and that chloroquine and TLR9 inhibitors represent viable broad-spectrum and targeted therapeutic strategies, respectively, that are promising candidates for further clinical development.
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14
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Ashton N, Al-Wasil SH, Bond H, Berry JL, Denton J, Freemont AJ. The effect of a low-protein diet in pregnancy on offspring renal calcium handling. Am J Physiol Regul Integr Comp Physiol 2007; 293:R759-65. [PMID: 17567711 DOI: 10.1152/ajpregu.00523.2006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Low birth weight humans and rats exposed to a low-protein diet in utero have reduced bone mineral content. Renal calcium loss during the period of rapid skeletal growth is associated with bone loss. Because young rats exposed to low protein display altered renal function, we tested the hypothesis that renal calcium excretion is perturbed in this model. Pregnant Wistar rats were fed isocalorific diets containing either 18% (control) or 9% (low) protein throughout gestation. Using standard renal clearance techniques, Western blotting for renal calcium transport proteins, and assays for Na+-K+-ATPase activity and serum calcitropic hormones, we characterized calcium handling in 4-wk-old male offspring. Histomorphometric analyses of femurs revealed a reduction in trabecular bone mass in low-protein rats. Renal calcium (control vs. low protein: 10.4 ± 2.1 vs. 27.6 ± 4.5 nmol·min−1·100 g body wt−1; P < 0.01) and sodium excretion were increased, but glomerular filtration rate was reduced in low-protein animals. Total plasma calcium was reduced in low-protein rats ( P < 0.01), but ionized calcium, serum calcitropic hormone concentrations, and total body calcium did not differ. There was no significant change in plasma membrane Ca2+-ATPase pump, epithelial calcium channel, or calbindin-D28K expression in low-protein rat kidneys. However, Na+-K+-ATPase activity was 36% lower ( P < 0.05) in low-protein rats. These data suggest that the hypercalciuria of low-protein rats arises through a reduction in passive calcium reabsorption in the proximal tubule rather than active distal tubule uptake. This may contribute to the reduction in bone mass observed in this model.
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Affiliation(s)
- Nick Ashton
- Faculty of Life Sciences, University of Manchester, 1.124 Stopford Bldg., Oxford Road, Manchester M13 9PT, UK.
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15
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Ahmed MH. Chloroquine-induced nitric oxide as a potential treatment of erectile dysfunction associated with the metabolic syndrome: the science and the fiction. Expert Opin Emerg Drugs 2007; 12:191-3. [PMID: 17604495 DOI: 10.1517/14728214.12.2.191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Erectile dysfunction is an important cause of decreased quality of life in men. It is estimated that approximately 30 million men in the US and 100 million worldwide may have erectile dysfunction. Data from epidemiological studies indicate a higher prevalence of impotence in obese men. Obesity may be a risk factor for sexual dysfunction in both sexes; data for the metabolic syndrome are very preliminary and need to be confirmed in larger epidemiological studies. The high prevalence of erectile dysfunction in patients with cardiovascular risk factors suggests that abnormalities of the vasodilator system of penile arteries play an important role in the pathophysiology of erectile dysfunction. Nitric oxide released during non-adrenergic, non-cholinergic neurotransmission and from the endothelium is probably the principal neurotransmitter mediating penile erection. It has been shown that chloroquine administration was associated with an increase in nitric oxide synthesis. Chloroquine was also postulated to enhance insulin sensitivity, which suggests potential benefit in treating the metabolic syndrome-related erectile dysfunction.
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Affiliation(s)
- Mohamed H Ahmed
- Southampton General Hospital, Chemical Pathology Department, Mail point 6, Level D, South Academic Block, Tremona Road, Southampton, SO16 6YD, UK.
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Abstract
Although chloroquine, hydroxychloroquine and quinacrine were originally developed for the treatment of malaria, these medications have been used to treat skin disease for over 50 years. Recent clinical data have confirmed the usefulness of these medications for the treatment of lupus erythematosus. Current research has further enhanced our understanding of the pharmacologic mechanisms of action of these drugs involving inhibition of endosomal toll-like receptor (TLR) signaling limiting B cell and dendritic cell activation. With this understanding, the use of these medications in dermatology is broadening. This article highlights the different antimalarials used within dermatology through their pharmacologic properties and mechanism of action, as well as indicating their clinical uses. In addition, contraindications, adverse effects, and possible drug interactions of antimalarials are reviewed.
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Affiliation(s)
- Sunil Kalia
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada
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Osman MM, Khalil A, Ahmed MH. Chloroquine-induced nitric oxide: new treatment for an emerging epidemic of obesity-related glomerulopathy. Diabetes Technol Ther 2006; 8:691-2. [PMID: 17109602 DOI: 10.1089/dia.2006.8.691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Ahmed MH, Osman MM. Why does chloroquine impair renal function?: chloroquine may modulate the renal tubular response to vasopressin either directly by inhibiting cyclic AMP generation, or indirectly via nitric oxide. Med Hypotheses 2006; 68:140-3. [PMID: 16919890 DOI: 10.1016/j.mehy.2006.06.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2006] [Revised: 06/06/2006] [Accepted: 06/07/2006] [Indexed: 11/24/2022]
Abstract
Chloroquine is one of the antimalaria drugs, also used to treat rheumatoid arthritis and systemic lupus erythematosus (SLE). Although well tolerated in most individuals, it was suggested that chloroquine can exert a profound influence on renal function, especially in individuals with compromised body fluid status. However, epidemiological studies are still lacking. The renal actions of chloroquine are further exacerbated by co-administration of other commonly used drugs such as paracetamol. The following discussion will focus on the evidence that chloroquine is a stimulator of nitric oxide (NO), which mediates many of its renal actions (diuresis, natriuresis and an increase in both glomerular filtration rate (GFR) and plasma vasopressin). Chloroquine appears to modulate the renal tubular response to vasopressin either by directly inhibiting cAMP generation or indirectly via NO.
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Affiliation(s)
- Mohamed H Ahmed
- Chemical Pathology Department, Southampton General Hospital, Tremona Road, Southampton, Hamphshire SO16 6YD, UK.
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Ahmed MH. Nitric oxide might be involved in the chloroquine-improved insulin sensitivity: old treatment for global danger. Diabetes Res Clin Pract 2006; 72:110-1. [PMID: 16256240 DOI: 10.1016/j.diabres.2005.09.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2005] [Accepted: 09/21/2005] [Indexed: 11/27/2022]
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Ahmed MH. Chloroquine-induced nitric oxide improves insulin sensitivity in rheumatoid arthritis. Med Hypotheses 2005; 66:208-9. [PMID: 16216434 DOI: 10.1016/j.mehy.2005.08.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Accepted: 08/28/2005] [Indexed: 10/25/2022]
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Bond H, Sibley CP, Balment RJ, Ashton N. Increased renal tubular reabsorption of calcium and magnesium by the offspring of diabetic rat pregnancy. Pediatr Res 2005; 57:890-5. [PMID: 15774836 DOI: 10.1203/01.pdr.0000157720.50808.97] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Diabetic pregnancy has a marked influence on offspring calcium and magnesium homeostasis. Urinary excretion of calcium and magnesium is reduced, yet offspring of diabetic pregnancy exhibit hypomagnesemia and hypocalcemia. The aim of this study was to measure renal hemodynamic and tubular function in the offspring of diabetic (OD) and control, nondiabetic (OC) rats at 4 and 8 wk of age to determine the glomerular and tubular mechanisms through which renal calcium and magnesium handling are programmed in utero. The fraction of filtered calcium that was excreted was significantly lower in OD at both 4 and 8 wk of age [8 wk: OC (n = 6), 11.8 +/- 2.9 versus OD (n = 5), 4.3 +/- 0.6%; p < 0.05] and that of magnesium was lower at 8 wk of age [OC (n = 6), 42.4 +/- 7.5 versus OD (n = 5), 13.0 +/- 1.7%; p < 0.01]. This increased reabsorption occurred despite an elevated GFR in OD. These findings clearly indicate that tubular reabsorptive mechanisms for calcium and magnesium are increased markedly in OD. Serum PTH concentration was reduced in 8-wk-old OD [OC (n = 7), 539.4 +/- 142.1 versus OD (n = 9), 174.3 +/- 69.4 pg/ml; p < 0.05], consistent with previous reports in human infants. Taken together, these observations suggest that the basis for the altered renal magnesium and calcium handling in OD involves increased tubular transport activity and possibly increased sensitivity of these mechanisms to PTH.
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Affiliation(s)
- Helen Bond
- Academic Unit of Child Health, University of Manchester, M13 9PT, UK
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Abstract
Rapid, nongenomic actions of aldosterone have been demonstrated in a number of cell types in vitro, including renal cell lines, but there remains little direct evidence that it is able to exert rapid effects on the kidney in the whole animal. Accordingly, the aim of this study was to determine whether aldosterone induces rapid changes in the renal handling of electrolytes or acid-base balance in the anesthetized rat. With the use of a servo-controlled fluid replacement system, spontaneous urine output by anesthetized male Sprague-Dawley rats was replaced with 2.5% dextrose. After a 3-h equilibration and a 1-h control period, rats were infused with aldosterone (42 pmol/min) or vehicle for 1 h. Aldosterone infusion induced a rapid (within 15 min) increase in sodium excretion that peaked at 0.24 ± 0.08 compared with 0.04 ± 0.01 μmol·min−1 100·body weight−1 ( P = 0.041) in the vehicle-infused rats. This natriuresis was not associated with changes in glomerular filtration rate; urine flow rate; potassium, chloride, or bicarbonate excretion; or urine pH. The mechanisms involved are unclear, but because we have previously shown that aldosterone stimulates a rapid (4 min) increase in cAMP generation in the rat inner medullary collecting duct (IMCD) (Sheader EA, Wargent ET, Ashton N, and Balment RJ. J Endocrinol 175: 343–347, 2002), they could involve cAMP-mediated activation of the cystic fibrosis transmembrane conductance regulator chloride channel, which drives sodium secretion in the IMCD.
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Affiliation(s)
- Abolfazl K Rad
- School of Biological Sciences, Univ. of Manchester, G.38 Stopford Bldg., Oxford Rd., Manchester M13 9PT, UK
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Ahmed MH. Vasopressin: a pre-requiste for some actions of renal nitric oxide? Med Hypotheses 2005; 64:218. [PMID: 15533647 DOI: 10.1016/j.mehy.2004.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Bogzil AH, Eardley R, Ashton N. Relaxin-induced changes in renal sodium excretion in the anesthetized male rat. Am J Physiol Regul Integr Comp Physiol 2005; 288:R322-8. [PMID: 15388493 DOI: 10.1152/ajpregu.00509.2004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pregnancy is associated with profound changes in renal hemodynamics and electrolyte handling. Relaxin, a hormone secreted by the corpus luteum, has been shown to induce pregnancy-like increases in renal blood flow and glomerular filtration rate (GFR) and alter osmoregulation in nonpregnant female and male rats. However, its effects on renal electrolyte handling are unknown. Accordingly, the influence of short (2 h)- and long-term (7 day) infusion of relaxin on renal function was determined in the male rat. Short term infusion of recombinant human relaxin (rhRLX) at 4 μg·h−1·100 g body wt−1 induced a significant increase in effective renal blood flow (ERBF) within 45 min, which peaked at 2 h of infusion (vehicle, n = 6, 2.1 ± 0.4 vs. rhRLX, n = 7, 8.1 ± 1.1 ml·min−1·100 g body wt−1, P < 0.01). GFR and urinary excretion of electrolytes were unaffected. After a 7-day infusion of rhRLX at 4 μg/h, ERBF (1.4 ± 0.2 vs. 2.5 ± 0.4 ml·min−1·100 g body wt−1, P < 0.05), urine flow rate (3.1 ± 0.3 vs. 4.3 ± 0.4 μl·min−1·100 g body wt−1, P < 0.05) and urinary sodium excretion (0.8 ± 0.1 vs. 1.2 ± 0.1 μmol·min−1·100 g body wt−1, P < 0.05) were significantly higher; plasma osmolality and sodium concentrations were lower in rhRLX-treated rats. These data show that long-term relaxin infusion induces a natriuresis and diuresis in the male rat. The mechanisms involved are unclear, but they do not involve changes in plasma aldosterone or atrial natriuretic peptide concentrations.
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Affiliation(s)
- Alsadek H Bogzil
- School of Biological Sciences, University of Manchester, G.38 Stopford Bldg., Oxford Rd., Manchester M13 9PT, UK
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Ahmed MH, Balment RJ, Ashton N. Renal action of acute chloroquine and paracetamol administration in the anesthetized, fluid-balanced rat. J Pharmacol Exp Ther 2003; 306:478-83. [PMID: 12721325 DOI: 10.1124/jpet.103.051037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Chloroquine induces diuresis, natriuresis, and an increase in glomerular filtration rate (GFR) in the rat. These responses are modified in rats with analgesic nephropathy induced by long-term paracetamol (acetaminophen) administration. Here, the effects of acute paracetamol treatment on renal function and the response to chloroquine are reported. Under intraval anesthesia (100 mg kg-1) male Sprague-Dawley rats (n = 6/group) were infused with 2.5% dextrose for 3 h. After a control hour, they received either vehicle, chloroquine (0.04 mg h-1), paracetamol (priming dose of 210 mg kg-1 followed by 110 mg kg-1h-1) or chloroquine and paracetamol over the next hour. Compared with vehicle, chloroquine infusion resulted in increases in GFR (2.4 +/- 0.3 versus 4.8 +/- 0.6 ml min-1), urine flow (4.2 +/- 0.3 versus 10.4 +/- 0.7 ml h-1), and sodium excretion (47.7 +/- 4.1 versus 171.2 +/- 18.6 micromol h-1) and a reduction in urine osmolality (223.2 +/- 5.9 versus 121.7 +/- 23.9 mOsM kg-1). Paracetamol reduced sodium excretion but had no effect on urine flow, GFR, or urine osmolality. When combined, paracetamol blocked the chloroquine-induced diuresis (3.9 +/- 0.7 ml h-1) and natriuresis (22.6 +/- 8.5 micromol h-1), attenuated the increase in glomerular filtration rate (3.5 +/- 0.2 ml min-1), and raised urine osmolality (280.0 +/- 22.8 mOsM kg-1). The differing effects of acute and long-term paracetamol treatment on basal and chloroquine-mediated renal function suggest that the length of prior exposure to paracetamol, and thus the presence of analgesic nephropathy, is an important determinant of the renal response to chloroquine.
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Affiliation(s)
- Mohamed H Ahmed
- School of Biological Sciences, University of Manchester, Manchester M13 9PT, UK
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Ahmed MH, Ashton N, Balment RJ. Renal function in a rat model of analgesic nephropathy: effect of chloroquine. J Pharmacol Exp Ther 2003; 305:123-30. [PMID: 12649360 DOI: 10.1124/jpet.102.047233] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The antimalaria drug chloroquine is often taken against a background of analgesic nephropathy caused by nonsteroidal anti-inflammatory drugs such as paracetamol (acetaminophen). Chloroquine has marked effects on the normal kidney and stimulates an increase in plasma vasopressin via nitric oxide. The aim of this study was to determine the renal action of chloroquine in a model of analgesic nephropathy. Sprague-Dawley rats (n = 6-8/group) were treated with paracetamol (500 mg kg(-1) day(-1)) for 30 days in drinking water to induce analgesic nephropathy; control rats received normal tap water. Under intraval anesthesia (100 mg kg(-1)) rats were infused with 2.5% dextrose for 3 h to equilibrate and after a control hour they received either vehicle, chloroquine (0.04 mg h(-1)), N(omega)-nitro-L-arginine methyl ester (L-NAME, nitric-oxide synthase inhibitor, 60 micro g kg(-1) h(-1)) or combined chloroquine and L-NAME over the next hour. Plasma was collected from a parallel group of animals for vasopressin radioimmunoassay. Long-term paracetamol treatment resulted in a decrease in glomerular filtration rate (p < 0.05), sodium excretion (p < 0.001), and urine osmolality (p < 0.001), but no change in urine flow rate compared with untreated animals. Chloroquine administration in paracetamol treated rats induced a significant reduction (p < 0.05) in urine flow rate and a significant increase in plasma vasopressin (p < 0.001). These effects were blocked by coadministration of L-NAME and thus seem to be mediated by a pathway involving nitric oxide. However, these responses contrast with the chloroquine-induced diuresis previously observed in untreated rats, possibly reflecting paracetamol inhibition of renal prostaglandin synthesis and consequent moderation of vasopressin's action.
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Affiliation(s)
- Mohamed H Ahmed
- School of Biological Sciences, University of Manchester, Manchester, United Kingdom
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