41 results on '"Vairappan B"'
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2. 553 LEPTIN ADMINISTRATION REGULATES HEPATIC CHOLESTEROL SYNTHESIS IN A MOUSE MODEL OF ALCOHOLIC FATTY LIVER DISEASE
- Author
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Vairappan, B., primary, Gopal, M., additional, and Namasivayam, N., additional
- Published
- 2013
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3. 595 INFLAMMATION UPREGULATES HEPATIC CONNEXIN-43 EXPRESSION IN CIRRHOSIS WHICH DEFINES SUSCEPTIBILITY TO DEVELOPMENT OF ACUTE-ON CHRONIC LIVER FAILURE
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Vairappan, B., primary, Davies, N., additional, Mookerjee, R., additional, Becker, D.L., additional, Warner, A., additional, and Jalan, R., additional
- Published
- 2012
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4. Nimbolide attenuates hepatocellular carcinoma by regulating miRNAs 21, 145 and 221 and their target gene expression.
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Vairappan B, Mukherjee V, Subramanian SB, Ram AK, and Ravikumar TS
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- Animals, Mice, Male, Cell Proliferation drug effects, MicroRNAs genetics, MicroRNAs metabolism, Carcinoma, Hepatocellular drug therapy, Carcinoma, Hepatocellular genetics, Carcinoma, Hepatocellular metabolism, Carcinoma, Hepatocellular pathology, Liver Neoplasms drug therapy, Liver Neoplasms genetics, Liver Neoplasms metabolism, Liver Neoplasms pathology, Gene Expression Regulation, Neoplastic drug effects, Limonins pharmacology
- Abstract
Background and Aims: MicroRNAs (miRNAs) are becoming progressively emerging in cancer research from an etiologic and curative point of view. Several miRNAs act as oncogenes or tumor suppressors, which are dysregulated in numerous cancers. Our previous studies have established that nimbolide (a bioactive terpenoid from neem) attenuated hepatocellular carcinoma (HCC) through various mechanisms in mice. Here, we aimed to elucidate the effect of nimbolide in modulating specific miRNAs (21, 145, and 221) and their target genes involved in promoting inflammation and cancer cell proliferation in HCC mice., Methods: Following the induction of HCC in mice at 28 weeks, nimbolide (6 mg/kg b.wt.) was administered orally for four consecutive weeks., Results: We found significantly increased hepatic expression of miR-21a-3p, miR-21a-5p, miR-221-5p and miR-221-3p whilst significantly decreased miR-145a-5p in HCC mice. Nimbolide treatment to HCC mice substantially reduced the miR-21a-5p and miR-221-3p and improved miR-145a-5p gene expression. Our in-silico study also supports these findings. Moreover, hepatic tight junction (TJ) associated proteins such as claudins 1&5 mRNA and protein were increased considerably, whilst significantly decreased hepatic claudin 2 mRNA and protein expression noted in HCC mice. Nimbolide also regulates cadherins, ROCK 1, MMP 9, cyclin D1, CDK4, NF κB and TNFα mRNA expression in HCC mice., Conclusion: We identified for the first time that nibmolide treatment to HCC mice significantly attenuated hepatic miRNAs 21 & 221 expressions and sheltered miR-145 expression. These findings were further confirmed with in-silico studies. Moreover, nibmolide treatment in HCC mice regulates miRNA target genes involved in cancer cell proliferation and inflammation, thereby attenuating HCC progression in mice., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
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- 2025
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5. NOSTRIN is an emerging positive regulator of decompensated cirrhotic patients with portal hypertension.
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Vairappan B, Ts R, Ram AK, Mohan P, and Pottakkat B
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- Humans, Male, Female, Middle Aged, Case-Control Studies, Adult, Liver metabolism, Cyclic GMP metabolism, Aged, Hypertension, Portal metabolism, Liver Cirrhosis complications, Liver Cirrhosis metabolism, Nitric Oxide Synthase Type III metabolism, Biomarkers blood, Biomarkers metabolism, Nitric Oxide metabolism
- Abstract
Background and Aims: Decreased nitric oxide (NO) bioavailability in a cirrhotic liver contributes to high intrahepatic vascular resistance (IHVR) and portal hypertension (PHT). Nostrin is an inhibitory protein of NO synthesising enzyme endothelial NO synthase (eNOS), shown to increase in cirrhosis with PHT, however, the precise molecular mechanism is poorly documented. This study aimed to elucidate the role of Nostrin and associated derangement in hepatic NO generation in cirrhotic liver. Further, we investigate whether Nostrin could be a biomarker in the progression of cirrhosis., Methods: This study was conducted on sixty healthy subjects and 120 cirrhotic patients. In addition, liver tissue samples were collected from cirrhotic patients for the analysis of Nostrin, eNOS and inflammatory markers., Results: When compared to healthy controls, systemic levels of Nostrin and cGMP were elevated in compensated cirrhosis. In decompensated cirrhosis, further robust increases in Nostrin and cGMP were noted. Furthermore, Nostrin expression was considerably higher whilst reduced eNOS activity and hepatic cGMP levels in cirrhotic liver compared to control liver., Conclusions: In cirrhotic patients, a robust increase in hepatic Nostrin expression may reduce eNOS activity and associated local NO generation. Furthermore, Blood Nostrin concentration was higher and parallel to disease severity and could be a key diagnostic and prognostic biomarker in cirrhotic patients with PHT., Competing Interests: Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)
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- 2025
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6. Does lung ultrasound-guided ultrafiltration lead to better outcomes in acute kidney injury requiring intermittent hemodialysis: A randomized control trial.
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Zachariah VK, Sunitha VC, Ramachandran N, Vairappan B, Parameswaran S, and Priyamvada PS
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- Humans, Male, Female, Middle Aged, Renal Dialysis methods, Ultrasonography methods, Ultrafiltration methods, Aged, Adult, Acute Kidney Injury therapy, Lung diagnostic imaging
- Abstract
Introduction: Optimization of ultrafiltration during hemodialysis is a critical parameter in achieving therapeutic efficacy and ensuring hemodynamic stability. While various modalities such as blood volume monitoring, inferior vena cava diameter assessment, natriuretic peptide levels, bioimpedance assay, and lung ultrasound have been widely explored in the context of maintenance hemodialysis, the concept of volume-guided ultrafiltration in dialysis patients with acute kidney injury remains unexplored., Methods: Adult patients with acute kidney injury requiring dialysis, who were hemodynamically stable and not on ventilator support, without underlying lung pathology or cardiac failure, were randomized into two groups. All patients underwent 28-zone lung ultrasound before dialysis. The ultrafiltration was decided based on the treating physician's clinical judgment in controls. In the intervention group, the ultrafiltration orders prescribed by the treating physician were modified, based on the Kerley B line scores obtained by lung ultrasound. The rest of the dialysis prescriptions were similar. A postdialysis lung ultrasound was done in both groups to assess the postdialysis volume status 30 min after the dialysis session., Results: A total of 74 patients undergoing hemodialysis for acute kidney injury were randomized. The baseline characteristics were comparable except for higher baseline B line score scores in the intervention arm. All patients received similar dialysis prescriptions. The lung ultrasound-guided ultrafiltration arm had a higher change in B line scores (BLS) from baseline (4 [0-9.5] vs. 0 [0-4]; p value 0.004) during the first dialysis session. The predialysis BLS indexed to ultrafiltration (mL/kbw/h) were significantly lower in controls, reflecting a relatively higher rate of ultrafiltration in controls compared with intervention (p = 0.006). The total number of dialysis sessions done in the control and intervention arm were 61 and 59, respectively. Among controls, 23/61 sessions (37.7%) had intradialytic adverse events, whereas, in the intervention arm, only 4/59 sessions (6.7) had any adverse intradialytic events (p < 0.01)., Conclusion: Lung ultrasound-guided ultrafiltration was associated with a better safety profile, as demonstrated by reduced intradialytic events., (© 2024 International Society for Hemodialysis.)
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- 2024
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7. Agreement between equation-derived body fat estimator and bioelectrical impedance analysis for body fat measurement in middle-aged southern Indians.
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Endukuru CK, Gaur GS, Yerrabelli D, Sahoo J, and Vairappan B
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- Humans, Male, Female, Middle Aged, Adult, India, Adiposity, Metabolic Syndrome diagnosis, Metabolic Syndrome physiopathology, Reproducibility of Results, Body Composition physiology, Electric Impedance, Adipose Tissue
- Abstract
Excess body fat (BF) contributes to metabolic syndrome (MetS). The Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) is an equation-derived body fat estimator proposed to assess BF. However, its efficiency compared to the standard method is unknown. We aimed to compare the efficacy of CUN-BAE with the standard method in estimating BF in southern Indians. We included 351 subjects, with 166 MetS patients and 185 non-MetS subjects. BF was obtained from the standard bioelectrical impedance analysis (BIA) method and measured by CUN-BAE in the same subjects. We compared the efficacy of CUN-BAE in estimating BF with that of BIA via Bland-Altman plots, intraclass correlation coefficients, concordance correlation coefficients and the kappa index. The mean body fat percentage (BF%) values measured by BIA and CUN-BAE in all the subjects were 28.91 ± 8.94 and 29.22 ± 8.63, respectively. We observed significant absolute agreement between CUN-BAE and BIA for BF%. BIA and CUN-BAE showed good reproducibility for BF%. CUN-BAE had accuracy comparable to BIA for detecting MetS using BF%. Our findings indicate that CUN-BAE provides precise BF estimates similar to the BIA method, making it suitable for routine clinical practice when access to BF measurement devices is limited., (© 2024 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)
- Published
- 2024
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8. Comparison of the efficacy of 0.9% normal saline with balanced crystalloid (Plasmalyte) in maintaining the metabolic profile in head injury patients undergoing evacuation of acute subdural haematoma - A randomised controlled trial.
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Sakkanan NV, Swaminathan S, Bidkar PU, Vairappan B, Sathiaprabhu A, and Dey A
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Background and Aims: The choice of intravenous fluids is important in patients with traumatic brain injury (TBI), where large volumes may be required for resuscitation. Our study aimed to compare 0.9% normal saline (NS) with balanced crystalloid (Plasmalyte) in TBI patients in terms of metabolic and coagulation profile, brain relaxation score (BRS) and renal functions using serum urea, creatinine and urinary tissue inhibitor of metalloproteinases-2* insulin-like growth factor binding protein-7, [TIMP-2]*[IGFBP7], value to assess the risk of acute kidney injury., Methods: This randomised controlled trial on 90 TBI patients undergoing emergency craniotomy and subdural haematoma evacuation was conducted in a tertiary care institute. The patients were randomised to receive either NS (Group NS) or Plasmalyte (Group P) as the intraoperative maintenance fluid. The primary outcome measures included the potential of hydrogen (pH), base excess (BE) and chloride values from an arterial blood gas. The secondary outcomes were the coagulation profile, BRS and urinary [TIMP-2]*[IGFBP7]. The two groups' metabolic profile differences were analysed using two-way repeated analysis of variance. BRS was analysed using the Mann-Whitney U test. A P value < 0.05 was considered to be statistically significant., Results: The pH and chloride values were significantly higher, and the BE values were significantly lower in Group P compared to Group NS ( P < 0.001). Brain relaxation and coagulation profiles were comparable between the two groups. Serum creatinine ( P = 0.002) and urinary [TIMP-2]*[IGFBP7] ( P = 0.042) were significantly higher in the NS group., Conclusion: Plasmalyte maintains a more favourable metabolic profile than NS in TBI patients without affecting brain relaxation adversely., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Indian Journal of Anaesthesia.)
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- 2024
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9. Randomized Trial on the Efficacy and Safety of Standard Versus Higher Bicarbonate Supplementation in CKD of Unknown Etiology.
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Raju S, Manoharan K, Ramachandran N, Sahoo J, Vairappan B, Subramaniyam V, Parameswaran S, and Priyamvada PS
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- 2024
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10. Candesartan cilexetil ameliorates NOSTRIN-NO dependent portal hypertension in cirrhosis and ACLF.
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Vairappan B, Wright G, M S, and Ravikumar TS
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- Animals, Humans, Mice, Adaptor Proteins, Signal Transducing metabolism, Caveolin 1 metabolism, DNA-Binding Proteins metabolism, Endothelial Cells metabolism, Inflammation complications, Lipopolysaccharides, Liver Cirrhosis complications, Liver Cirrhosis drug therapy, NF-kappa B metabolism, Nitric Oxide Synthase metabolism, Nitric Oxide Synthase Type III metabolism, Portal Pressure, Acute-On-Chronic Liver Failure complications, Hypertension, Portal complications, Hypertension, Portal drug therapy
- Abstract
In decompensated cirrhosis, the severity of portal hypertension (PHT) is associated with increased hepatic endothelial nitric oxide synthase (eNOS) trafficking inducer (Nostrin), but the mechanism remains unclear. AIM: To investigate: (1) Whether in cirrhosis-PHT models, ± superimposed inflammation to mimic acute-on-chronic liver failure (ACLF) modulates hepatic nitric oxide synthase trafficking inducer (NOSTRIN) expression, nitric oxide (NO) synthesis, and/or endothelial dysfunction (ED); and (2) Whether the "angiotensin II type 1 receptor blocker" candesartan cilexetil (CC) affects this pathway. CD-1 mice received intraperitoneal carbon tetrachloride injections (CCl
4 15% v/v in corn oil, 0.5 mL/kg) twice weekly for 12 wk to induce cirrhosis. After 12 wk, mice were randomized to receive 2-wk oral administration of CC (8 mg/kg) ± LPS. At sacrifice, plasma (biochemical indicators, cytokines, and angiotensin II) and liver tissues (histopathology, Sirius-red stains, and molecular studies) were analysed. Moreover, Nostrin gene knockdown was tested in human umbilical vein endothelial cells (HUVECs). When compared to naïve animals, CCl4 -treated animals showed markedly elevated hepatic Nostrin expression (P < 0.0001), while hepatic peNOS expression (measure of eNOS activity) was significantly reduced (P < 0.05). LPS challenge further increased Nostrin and reduced peNOS expression (P < 0.05 for both) in cirrhotic animals. Portal pressure and subsequent hepatic vascular resistance were also increased in all cirrhotic animals following LPS challenge. In CCl4 ± LPS-treated animals, CC treatment significantly reduced Nostrin (P < 0.05) and increased hepatic cGMP (P < 0.01). NOSIP, caveolin-1, NFκB, and iNOS protein expression were significantly increased in CCl4 -treated animals (P < 0.05 for all). CC treatment non-significantly lowered NOSIP and caveolin-1 expression while iNOS and NFκB expression was significantly reduced in CCl4 + LPS-treated animals (P < 0.05 for both). Furthermore, Nostrin knockdown significantly improved peNOS expression and associated NO synthesis and reduced inflammation in HUVECs. This study is the first to indicate a potential mechanistic role for the Nostrin-eNOS-NO pathway in cirrhosis and ACLF development. Moreover, this pathway provides a potential therapeutic target given the ameliorative response to Candesartan treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
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11. Placental expression of striatin & endothelial nitric oxide synthase in women with & without pre-eclampsia.
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Viveka M, Chaturvedula L, Ram AK, and Vairappan B
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- Female, Humans, Pregnancy, Nitric Oxide, Nitric Oxide Synthase analysis, Nitric Oxide Synthase metabolism, Placenta chemistry, Placenta metabolism, Nitric Oxide Synthase Type III genetics, Nitric Oxide Synthase Type III metabolism, Pre-Eclampsia
- Abstract
Background & Objectives: Striatin is a multi-domain scaffolding protein essential for activating endothelial nitric oxide synthase (eNOS). However, its role in pre-eclampsia remains use explored. Hence, this study aimed to investigate the association between striatin and eNOS in regulating nitric oxide (NO) production in the placenta of women with and without pre-eclampsia., Methods: Forty pregnant women each without (controls) and with pre-eclampsia (cases) were enrolled in the study. Blood striatin and NO concentrations were detected by the ELISA. Protein expression of striatin, phosphorylated eNOS (peNOS), inducible NOS (iNOS) and phosphorylated NF-κB were measured in the placental tissues by Western blot. Twenty four hour urinary protein and serum urea, uric acid and creatinine were analyzed as an autoanalyzer. Placental histology was analyzed by haematoxylin and eosin staining. Results: Compared to normotensive pregnant women, the levels of serum NO and striatin were decreased in pre-eclamptic women. The protein expression of striatin and peNOS was significantly reduced (P<0.05) while p65NF-κB and iNOS were upregulated considerably (P<0.05) in the placenta of cases compared to controls., Interpretation & Conclusions: Our results show for the first time that decreased striatin expression was associated with decreased peNOS protein expression in the placental tissue of pre-eclamptic women. Interestingly, no significant difference was found in blood striatin or NO levels between controls and cases. Thus, therapies that improve placental striatin expression are attractive possibilities, both for prevention as well as treatment of endothelial dysfunction in pre-eclampsia.
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- 2023
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12. Correlation among Poincare plot and traditional heart rate variability indices in adults with different risk levels of metabolic syndrome: a cross-sectional approach from Southern India.
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Endukuru CK, Gaur GS, Yerrabelli D, Sahoo J, Vairappan B, and Goud AC
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- Adult, Syndactyly, India, Humans, Autonomic Nervous System physiology, Heart Rate physiology, Metabolic Syndrome diagnosis
- Abstract
Objectives: Heart rate variability (HRV) is an important marker of cardiac autonomic modulation. Metabolic syndrome (MetS) can alter cardiac autonomic modulation, raising the risk of cardiovascular disease (CVD). Poincaré plot analysis (PPA) is a robust scatter plot-based depiction of HRV and carries similar information to the traditional HRV measures. However, no prior studies have examined the relationship between PPA and traditional HRV measures among different risk levels of MetS. We evaluated the association between the Poincare plot and traditional heart rate variability indices among adults with different risk levels of MetS., Methods: We measured anthropometric data and collected fasting blood samples to diagnose MetS. The MetS risk was assessed in 223 participants based on the number of MetS components and was classified as control (n=64), pre-MetS (n=49), MetS (n=56), and severe MetS (n=54). We calculated the Poincaré plot (PP) and traditional HRV measures from a 5 min HRV recording., Results: Besides the traditional HRV measures, we found that various HRV indices of PPA showed significant differences among the groups. The severe MetS group had significantly lower S (total HRV), SD1 (short-term HRV), SD2 (long-term HRV), and higher SD2/SD1. The values of S, SD1, SD2, and SD2/SD1 were significantly correlated with most traditional HRV measures., Conclusions: We found gradual changes in HRV patterns as lower parasympathetic and higher sympathetic activity alongside the rising number of MetS components. The HRV indices of PPA integrating the benefits of traditional HRV indices distinguish successfully between different risk levels of MetS and control subjects., (© 2022 Walter de Gruyter GmbH, Berlin/Boston.)
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- 2023
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13. Association between metabolic syndrome components and cardiac autonomic modulation in southern Indian adults with pre-metabolic syndrome: hyperglycemia is the major contributing factor.
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Kumar EC, Gaur GS, Yerrabelli D, Sahoo J, Vairappan B, and Goud AC
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Metabolic syndrome (MetS) involves multi-factorial conditions linked to an elevated risk of type 2 diabetes mellitus and cardiovascular disease. Pre-metabolic syndrome (pre-MetS) possesses two MetS components but does not meet the MetS diagnostic criteria. Although cardiac autonomic derangements are evident in MetS, there is little information on their status in pre-MetS subjects. In this study, we sought to examine cardiac autonomic functions in pre-MetS and to determine which MetS component is more responsible for impaired cardiac autonomic functions. A total of 182 subjects were recruited and divided into healthy controls (n=89) and pre-MetS subjects (n=93) based on inclusion and exclusion criteria. We performed biochemical profiles on fasting blood samples to detect pre-MetS. Using standardized protocols, we evaluated anthropometric data, body composition, baroreflex sensitivity (BRS), heart rate variability (HRV), and autonomic function tests (AFTs). We further examined these parameters in pre-MetS subjects for each MetS component. Compared to healthy controls, we observed a significant cardiac autonomic dysfunction (CAD) through reduced BRS, lower overall HRV, and altered AFT parameters in pre-MetS subjects, accompanied by markedly varied anthropometric, clinical and biochemical parameters. Furthermore, all examined BRS, HRV, and AFT parameters exhibited an abnormal trend and significant correlation toward hyperglycemia. This study demonstrates CAD in pre-MetS subjects with reduced BRS, lower overall HRV, and altered AFT parameters. Hyperglycemia was considered an independent determinant of alterations in all the examined BRS, HRV, and AFT parameters. Thus, hyperglycemia may contribute to CAD in pre-MetS subjects before progressing to MetS.
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- 2023
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14. The Burden of Peripheral Neuropathy in Nondiabetic Chronic Kidney Disease and the Role of Ghrelin Isoforms in its Development.
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Ramachandran M, Subramanian V, Kuppusamy S, Parameswaran S, Chinnakali P, and Vairappan B
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Introduction: Peripheral neuropathy is one of the most common complications in chronic kidney disease (CKD). The neuroprotective role of ghrelin is being explored recently. Here we aim to determine the burden of neuropathy in nondiabetic CKD and to find the association of peripheral nerve function with plasma ghrelin levels in these patients., Methods: This was a cross-sectional study conducted in nondiabetic CKD patients on conservative management to determine the magnitude of neuropathy. The association of ghrelin isoforms with nerve functions was assessed between three groups, namely CKD with neuropathy, CKD without neuropathy, and healthy volunteers, with 20 participants in each group., Results: The proportion of neuropathy in nondiabetic CKD was 78% ( n = 78), of which 51% ( n = 40) were asymptomatic. Des acyl ghrelin (DAG) and total ghrelin (TG) levels were 1545.5 ± 487.4 and 1567.4 ± 485.3 pg/mL, respectively, in CKD patients with neuropathy and were found to be elevated compared to those without neuropathy, who had 1000.4 ± 264.2 and 1019.7 ± 264.3 pg/mL of DAG and TG, respectively ( P < 0.001). Assessment of correlation between nerve conduction parameters and DAG levels showed positive correlation between DAG levels and common peroneal latency (r = 0.69; P < 0.01), median sensory latency (r = 0.45; P < 0.05), and sural latency (r = 0.51; P < 0.05). We found negative correlation between median velocity (r =-0.56; P < 0.05), common peroneal velocity (r = -0.64; P < 0.01), median sensory velocity (r =-0.49; P < 0.05), and sural velocity (r = -0.54; P < 0.05). There was no statistically significant difference in acyl ghrelin levels among the groups., Conclusion: The prevalence of peripheral neuropathy in CKD is significantly higher with almost half of them being asymptomatic. Impaired renal clearance in CKD leads to the accumulation of DAG, which subsequently inhibits the neuroprotective functions of AG leading to neuropathy in CKD., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Indian Journal of Nephrology.)
- Published
- 2022
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15. Nimbolide attenuates gut dysbiosis and prevents bacterial translocation by improving intestinal barrier integrity and ameliorating inflammation in hepatocellular carcinoma.
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Ram AK, Vairappan B, and Srinivas BH
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- Animals, Bacterial Translocation, Dysbiosis drug therapy, Inflammation drug therapy, Limonins, Mice, Carcinoma, Hepatocellular drug therapy, Liver Neoplasms drug therapy
- Abstract
Gut microbiota imbalance plays a key pathological role in hepatocellular carcinoma (HCC) progression; however, the mechanism is poorly understood. We previously showed nimbolide impede tumor development by improving hepatic tight junction (TJ) proteins expression and attenuating inflammation in HCC mice. Here, we aimed to study the role of nimbolide in regulating gut microbiota imbalance and bacterial translocation (BT) through modulating intestinal TJ proteins in an experimental hepatocarcinogenesis. Nimbolide (6 mg/kg) was administered orally for 4 weeks following induction of HCC in mice at the 28th week. Nimbolide treatment attenuated the gut microbiota imbalance by decreasing 16 s rRNA levels of Escherichia coli, Enterococcus, Bacteroides and increasing Bifidobacterium, and Lactobacillus in the intestinal tissue, which was otherwise altered in HCC mice. Furthermore, nimbolide improved intestinal barrier integrity in HCC mice by upregulating TJ proteins such as occludin and ZO-1 expression and subsequently prevented hepatic BT and decreased BT markers such as LBP, sCD14, and procalcitonin in the plasma of HCC mice. Moreover, nimbolide ameliorated intestinal and hepatic inflammation by downregulating TLR4, MyD88, and NF-κB protein expression in HCC mice. Thus, nimbolide represents a novel therapeutic drug for HCC treatment by targeting the gut-liver axis, which plays an imperative role in HCC pathogenesis., (© 2022 John Wiley & Sons Ltd.)
- Published
- 2022
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16. Role of zonula occludens in gastrointestinal and liver cancers.
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Ram AK and Vairappan B
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A growing body of evidence suggests that tight junction (TJ) proteins play a crucial role in the pathogenesis of various diseases, including gastrointestinal (GI) cancer and hepatocellular carcinoma (HCC). TJ proteins primarily maintain the epithelial and endothelial cells intact together through integral proteins however, recent reports suggest that they also regulate gene expression necessary for cell proliferation, angiogenesis, and metastasis through adapter proteins such as zonula occludens (ZO). ZO proteins are membrane-associated cytosolic scaffolding proteins that modulate cell proliferation by interacting with several transcription factors. Reduced ZO proteins in GI cancer and HCC are correlated with tumor development and poor prognosis. Pubmed has searched for using the keyword ZO and gastric cancer, ZO and cancer, and ZO and HCC for the last ten years to date. This review summarized the role of ZO proteins in cell proliferation and their expression in GI cancer and HCC. Furthermore, therapeutic interventions targeting ZO in GI and liver cancers are reviewed., Competing Interests: Conflict-of-interest statement: The authors declare that there is no conflict of interest related to this study., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)
- Published
- 2022
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17. Recognizing the importance of physical activity on sarcopenia in chronic kidney disease - Reply.
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Dubey AK, Sahoo J, Vairappan B, Parameswaran S, and Ps P
- Abstract
Competing Interests: The authors declare no competing interests.
- Published
- 2022
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18. Liver Injury in COVID-19: A Direct Hit or Collateral Damage?
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Vairappan B, Wright G, Corrigal D, and Ts R
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- Humans, Pandemics, SARS-CoV-2, COVID-19 complications, Liver Diseases complications, Liver Diseases epidemiology
- Abstract
SARS-CoV-2 is a novel coronavirus that has been identified, in December 2019, in Wuhan, China, and since it has become a worldwide pandemic, it has imposed far-reaching impacts on global human health and socio-economic activity. Worldwide, over 4 million Covid-19 related deaths were reported until September 2021. Recently published case studies have reported that Covid-19 patients develop different degrees of liver dysfunction. Inevitably, in hospitalized Covid-19 patients who develop acute liver derangement, there are a plethora of potential pathogenic causes such as direct-viral, immune-driven, and drug-induced and/or ischaemic liver injury. Patients with advanced chronic liver diseases (e.g., cirrhosis) and/or autoimmune liver disease have a poor immune function and associated poorer outcomes compared to other critically ill cohorts. However, largely any immediate liver derangement tends to be relatively mild, and as such, any de novo liver injury may not be a significant feature of Covid-19. There is an immediate necessity, therefore, to better understand the liver-specific pathophysiology of COVID-19. This review focuses on the up-to-date information regarding Covid-19 and associated indices for liver dysfunction, possible mechanisms, and potential drug targeted therapies in Covid-19 patients with and without liver dysfunction. PubMed database was used to perform an extensive literature search using the keywords liver and SARS-CoV-2, liver and Covid-19, Covid 19 and treatment, etc., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2022
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19. Response: Cut-off Values and Clinical Utility of Surrogate Markers for Insulin Resistance and Beta-Cell Function to Identify Metabolic Syndrome and Its Components among Southern Indian Adults (J Obes Metab Syndr 2020;29:281-91).
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Endukuru CK, Gaur GS, Yerrabelli D, Sahoo J, and Vairappan B
- Published
- 2021
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20. Prevalence and determinants of sarcopenia in Indian patients with chronic kidney disease stage 3 & 4.
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Dubey AK, Sahoo J, Vairappan B, Parameswaran S, and Ps P
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Objectives: There is limited literature on the prevalence and determinants of sarcopenia in the Indian predialysis chronic kidney disease (CKD) population. The current study attempts to characterize sarcopenia in CKD stages 3 & 4 using 3-compartment model dual-energy X-ray absorptiometry (DXA)., Methods: This is secondary data from a randomized trial on bicarbonate supplementation for preserving muscle mass. A 3-compartment DXA was done to assess body composition in 188 subjects aged 18 to 65, with stable kidney function. Sarcopenia was defined by Asian Working Group criteria - appendicular skeletal mass index < 5.4 kg/m
2 in women and < 7 kg/m2 in men., Results: Sarcopenia was present in 69.1% (n = 130). There was no difference in the prevalence of sarcopenia in CKD stage 3 (n = 62; 72.1%) vs CKD stage 4 (n = 68, 66.7%); P = 0.434. A lower body mass index (BMI) (OR 1.69; 95% CI 1.43, 2.01) and lower bicarbonate levels (OR 1.22; 95% CI 1.02, 1.47), and age (OR 0.95; 95% CI 0.91, 0.98) was independently associated with the muscle mass. A BMI cut-off of 18 failed to identify sarcopenia in 78.4% (n = 102) subjects (Kappa statistic 0.396). The receiver operating characteristic curve for mid-arm muscle circumference for identifying sarcopenia was 0.651 (95% CI 0.561, 0.740)., Conclusions: Sarcopenia is highly prevalent in CKD 3 and 4. Sarcopenic individuals are older, with a low BMI and lower bicarbonate levels. The anthropometric parameters and biochemical parameters did not help identify sarcopenia in the predialysis population., Competing Interests: The authors declare no competing interests., (© 2021 The Korean Society of Osteoporosis. Publishing services by Elsevier B.V.)- Published
- 2021
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21. Seasonal Changes in Kidney Function in CKD of Uncertain Etiology.
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Arora S, Ps P, Sahoo J, Vairappan B, and Parameswaran S
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- 2021
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22. Cut-off values and clinical efficacy of body roundness index and other novel anthropometric indices in identifying metabolic syndrome and its components among Southern-Indian adults.
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Endukuru CK, Gaur GS, Dhanalakshmi Y, Sahoo J, and Vairappan B
- Abstract
Context: Abdominal obesity (AO) is a definitive link between cardiometabolic complications and metabolic syndrome (MetS). Many traditional and novel anthropometric indices have been identified to determine AO, and their relationship to MetS has been investigated. However, whether these indices are useful in a clinical setting is unknown. Moreover, the cut-off points for these indices to determine MetS have yet to be defined among Southern-Indian adults., Aims: We aimed to evaluate the cut-off values and clinical efficacy of novel anthropometric indices in identifying MetS and its components., Materials and Methods: Subjects ( n = 202) were recruited and then grouped into cases (MetS = 106) and controls (healthy = 96). We measured anthropometric data and assayed glycemic and lipid profiles. Using these, we computed a-body shape index (ABSI), abdominal volume index (AVI), body adiposity index (BAI), body roundness index (BRI), conicity index (CI), lipid-accumulation product (LAP), visceral adiposity index (VAI) and waist-triglyceride index (WTI) from published equations., Results: Compared to the control group, all the novel anthropometric indices were noticeably higher in both male and female subjects of the MetS group. The area under the curve values (AUCs) demonstrated that BRI, CI, AVI, and WTI had superior detection power in identifying MetS, and the AUCs varied upon stratification by gender. BRI was strongly associated with the highest odds of having MetS (OR 66.03)., Conclusions: The optimal cut-off and AUC values attained for BRI, CI, AVI, and WTI have a clinical approach in identifying MetS and its components. The efficacy of these indices to identify MetS differed by gender., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Japan Diabetes Society 2021.)
- Published
- 2021
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23. Cut-off Values and Clinical Utility of Surrogate Markers for Insulin Resistance and Beta-Cell Function to Identify Metabolic Syndrome and Its Components among Southern Indian Adults.
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Endukuru CK, Gaur GS, Yerrabelli D, Sahoo J, and Vairappan B
- Abstract
Background: Insulin resistance (IR) is a collective clinical entity that exacerbates metabolic syndrome (MetS). As the gold-standard test to quantify IR involves intravenous insulin loading and repeated blood glucose monitoring, many indices have been developed for IR assessment for convenience. This study tested the ideal cut-off values and clinical utility of IR indices in identifying MetS., Methods: We recruited 150 subjects, 75 MetS patients and 75 healthy controls, then obtained written informed consent to participate in this study. We collected fasting blood samples for glucose and lipid profiles and calculated nineteen indices of IR and insulin secretion using validated formulae. We determined the precision of these IR indices using the area under the curve (AUC) in a receiver operating characteristic analysis., Results: Subjects with MetS have significantly higher IR coupled with lower insulin sensitivity and beta-cell function than controls. Among the surrogate markers of IR tested, the homeostatic model assessment of insulin resistance (HOMA-IR), HOMA-adiponectin (HOMA-AD), triglyceride-glucose (TyG) index, HOMA-1%S (insulin sensitivity), quantitative insulin sensitivity check index (QUICKI), McAuley index, single-point insulin sensitivity estimator (SPISE), and HOMA-2%B (beta-cell function) showed the highest AUC values for detecting MetS., Conclusion: Our study results suggest that the ideal cut-off and AUC values identified for HOMA-IR, HOMA-AD, the TyG index, HOMA-1%S, QUICKI, the McAuley index, SPISE, and HOMA-2%B offer a clinical approach to the early detection and risk stratification for MetS among people in southern India.
- Published
- 2020
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24. Nimbolide inhibits tumor growth by restoring hepatic tight junction protein expression and reduced inflammation in an experimental hepatocarcinogenesis.
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Ram AK, Vairappan B, and Srinivas BH
- Subjects
- Animals, Carcinogenesis, Diethylnitrosamine toxicity, Inflammation drug therapy, Limonins, Male, Mice, Molecular Docking Simulation, NF-kappa B, Tight Junction Proteins, Carcinoma, Hepatocellular drug therapy, Liver Neoplasms drug therapy
- Abstract
Background: Altered tight junction (TJ) proteins are correlated with carcinogenesis and tumor development. Nimbolide is a tetranotriterpenoid that has been shown to have antioxidant and anti-proliferative properties; however, its anticancer effects and molecular mechanism in hepatocellular carcinoma (HCC) remains obscure., Aim: To investigate the effect of nimbolide on TJ proteins, cell cycle progression, and hepatic inflammation in a mouse model of HCC., Methods: HCC was induced in male Swiss albino mice (CD-1 strain) by a single intraperitoneal injection of 100 mg/kg diethylnitrosamine (DEN) followed by 80 ppm N-nitrosomorpholine (NMOR) in drinking water for 28 wk. After 28 wk, nimbolide (6 mg/kg) was given orally for four consecutive weeks in DEN/NMOR induced HCC mice. At the end of the 32
nd week, all the mice were sacrificed and blood and liver samples were collected for various analyses. Macroscopic examinations of hepatic nodules were assessed. Liver histology and HCC tumor markers such as alpha-fetoprotein (AFP) and glypican-3 were measured. Expression of TJ proteins, cell proliferation, and cell cycle markers, inflammatory markers, and oxidative stress markers were analyzed. In silico analysis was performed to confirm the binding and modulatory effect of nimbolide on zonula occludens 1 (ZO-1), nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-κB), and tumor necrosis factor alpha (TNF-α)., Results: We found nimbolide treatment at a concentration of 6 mg/kg to HCC mice reduced hepatic tumor size by 52.08% and tumor volume ( P < 0.01), and delayed tumor growth in HCC mice with a concomitant reduction in tumor markers such as AFP levels ( P < 0.01) and glypican-3 expression ( P < 0.05). Furthermore, nimbolide treatment increased tight junction proteins such as ZO-1 and occludin expression ( P < 0.05, respectively) and reduced ZO-1 associated nucleic acid binding protein expression ( P < 0.001) in HCC mice liver. Nimbolide treatment to HCC mice also inhibited cell proliferation and suppressed cell cycle progression by attenuating proliferating cell nuclear antigen ( P < 0.01), cyclin dependent kinase ( P < 0.05), and CyclinD1 ( P < 0.05) expression. In addition, nimbolide treatment to HCC mice ameliorated hepatic inflammation by reducing NF-κB, interleukin 1 beta and TNF-α expression ( P < 0.05, respectively) and abrogated oxidative stress by attenuating 4-hydroxynonenal expression ( P < 0.01). Molecular docking studies further confirmed that nimbolide interacts with ZO-1, NF-κB, and TNF-α., Conclusion: Our current study showed for the first time that nimbolide exhibits anticancer effect by reducing tumor size, tumor burden and by suppressing cell cycle progression in HCC mice. Furthermore, nimbolide treatment to HCC mice ameliorated inflammation and oxidative stress, and improved TJ proteins expression. Consequently, nimbolide could be potentially used as a natural therapeutic agent for HCC treatment, however further human studies are warranted., Competing Interests: Conflict-of-interest statement: The authors declare that there is no conflict of interest related to this study., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)- Published
- 2020
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25. Severe acute respiratory syndrome coronavirus-2 infection and the gut-liver axis.
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Mohandas S and Vairappan B
- Subjects
- Humans, Liver pathology, Virus Shedding, COVID-19 complications, Dysbiosis virology, Gastrointestinal Diseases virology, Gastrointestinal Microbiome, Liver Diseases virology
- Abstract
Patients affected by coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, manifest various gastrointestinal and hepatic abnormalities alongside respiratory disorders. The identification of this virus in the feces of more than 50% of infected individuals indicates the possibility of viral shedding and fecal-to-oral transmission. Preliminary reports have also identified alterations in the intestinal microbiota profile in infected individuals. Moreover, COVID-19 patients manifest various degrees of liver injury characterized by alterations in liver enzymes. Digestive symptoms and liver abnormalities correlate with disease severity, the incidence of critical outcomes and patient's recovery. However, the pathogenic mechanisms behind COVID-19-induced abnormalities in the gut-liver axis seem to be multifactorial in origin. This review compiles current knowledge sourced from preclinical and clinical research and summarizes gastrointestinal and hepatic dysfunctions observed following SARS-CoV-2 infection, and also explores the possible mechanisms generating abnormalities in the gut-liver axis. Furthermore, this review sheds light on possible therapeutic targets against these disorders., (© 2020 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.)
- Published
- 2020
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26. Impaired baroreflex sensitivity and cardiac autonomic functions are associated with cardiovascular disease risk factors among patients with metabolic syndrome in a tertiary care teaching hospital of South-India.
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Endukuru CK, Gaur GS, Yerrabelli D, Sahoo J, and Vairappan B
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- Adolescent, Adult, Aged, Blood Pressure, Cardiovascular Diseases etiology, Case-Control Studies, Female, Follow-Up Studies, Heart Rate, Humans, Male, Middle Aged, Prognosis, Risk Factors, Young Adult, Autonomic Nervous System physiopathology, Baroreflex, Cardiovascular Diseases pathology, Insulin Resistance, Metabolic Syndrome complications
- Abstract
Background & Aim: Baroreflex sensitivity (BRS) and heart rate variability (HRV) have been proposed to assess early autonomic dysfunction in metabolic syndrome (MetS) patients. Autonomic dysfunction in MetS patients may increase the risk of developing cardiovascular disease (CVD). However, the association of BRS and HRV with CVD risk factors remains elusive in MetS. The primary aim of this study was to assess the BRS and HRV in MetS patients among South-Indian adults and check whether BRS and HRV are associated with CVD risk factors., Methods: We performed anthropometric indices, body composition, physiological parameters such as BRS, HRV, and other autonomic function tests in 176 subjects divided into MetS patients (n = 88) and healthy controls (n = 88). Fasting blood samples were collected for biochemical profiles and calculated insulin resistance indices, atherogenic index (AI), and rate pressure product (RPP)., Results: When compared to controls, we found significantly reduced BRS and an increased ratio of low-frequency (LF) to high-frequency (HF) power of HRV (LF/HF) in the MetS group. We observed significant differences in body composition and biochemical profiles among the MetS group. BRS and LF/HF ratio of HRV have shown a significant association with CVD risk factors in the MetS group., Conclusions: We observed autonomic dysfunction as low BRS and high LF/HF ratio of HRV in MetS patients. Additionally, the present results emphasize that the association of BRS and LF/HF ratio with anthropometric, glucose, lipid parameters, and other CVD risk factors may increase the susceptibility of MetS patients to higher CVD risk., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020. Published by Elsevier Ltd.)
- Published
- 2020
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27. Ginkgolide-A attenuates bacterial translocation through activating PXR and improving antimicrobial peptide Reg 3A in experimental cirrhosis.
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Mohandas S and Vairappan B
- Subjects
- Animals, Antimicrobial Cationic Peptides metabolism, Blotting, Western, Hep G2 Cells, Humans, Liver Cirrhosis, Experimental complications, Male, Mice, Molecular Docking Simulation, Pregnane X Receptor drug effects, Cathelicidins, Bacterial Translocation drug effects, Ginkgolides pharmacology, Lactones pharmacology, Liver Cirrhosis, Experimental metabolism, Pancreatitis-Associated Proteins metabolism, Pregnane X Receptor metabolism
- Abstract
Background and Aims: Bacterial translocation (BT) is strongly associated with disease progression and poor outcome in cirrhotic patients. The role of Pregnane X receptor (PXR) in regulating bacterial translocation in cirrhosis is unknown. We previously showed that Ginkgolide-A (GA), a natural PXR ligand, attenuated BT in cirrhotic mice by abrogating inflammation along the gut-liver-axis, and by protecting small intestinal tight junctions (TJ). Here, we aimed to investigate the effect of GA in activating PXR and associated antimicrobial peptides (AMPs) in regulating BT in experimental cirrhosis., Methods: Male Swiss albino mice were administered CCl
4 (0.5 mL/kg body-weight, i.p twice a week) for 12 consecutive weeks. After the 12th week, mice were randomized and administered with GA (100-mg/kg body-weight, oral) every-day for 2 weeks. At termination, blood, gut and liver tissues were collected for molecular studies., Results: GA treatment to cirrhotic mice significantly increased the expression of small intestinal PXR and Regenerating family member 3 alpha (Reg3A), which were otherwise reduced in CCl4 cirrhotic mice. Moreover, compared to naive mice a significantly reduced Lactobacillus, and increased Bacteroides and Enterococcus 16s rRNA levels were observed in the small intestine and liver of cirrhotic mice. Treatment with GA to cirrhotic mice significantly reduced intestinal overgrowth and translocation of Enterococcus and Bacteroides to the liver. Furthermore, GA treatment significantly attenuated intestinal permeability and BT marker soluble-CD14 (sCD14), which were increased in CCl4 cirrhotic mice., Conclusion: The study showed for the first time that, GA treatment to cirrhotic rodents attenuates BT, by improving PXR and Reg3A expression., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2020
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28. Changes in the levels of comet parameters before and after fluoxetine therapy in major depression patients.
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Panwar R, Sivakumar M, Menon V, and Vairappan B
- Abstract
Major depression belongs to mood disorders and characterized by worthlessness, no interest or happiness in any activity; lasting for atleast two weeks. Etio-pathological changes of major depression include oxidative stress leading to free radical synthesis which causes damage to carbohydrates, proteins, lipids and nucleic acids. Nucleic acid damage can be identified by either single or double strand breaks and for quantitative estimation of the same, neutral or alkaline comet assay is performed. Fluoxetine is the drug of choice for treatment of major depression having antioxidant function. In the current study eighty drug naïve major depression patients were recruited and comet parameters namely total comet length, head diameter and tail length were measured before starting the treatment and after completion of eight week fluoxetine therapy. The levels of comet parameters were higher in females than males suggesting higher prevalence of major depression among females. On categorizing into three age groups, the numbers of major depression patients belonging to 18-30 year age group were higher than 31-40 and 41-50 year age groups. All the parameters of deoxyribonucleic acid damage were reduced after eight week of fluoxetine therapy indicating that fluoxetine has anti-oxidant action along with its antidepressant properties, which cause reversal of oxidative stress induced damage occurring during major depression.
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- 2020
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29. Reliability of Anthropometry-Based Equations Compared to Dual Energy Absorptiometry for Assessing Body Composition in Predialysis Chronic Kidney Disease-A Longitudinal Study.
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Dubey AK, Priyamvada PS, Sahoo J, Vairappan B, Haridasan S, and Parameswaran S
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- Absorptiometry, Photon, Adipose Tissue, Anthropometry, Body Mass Index, Electric Impedance, Humans, Longitudinal Studies, Reproducibility of Results, Skinfold Thickness, Body Composition, Renal Insufficiency, Chronic
- Abstract
Objectives: Skinfold thickness measurements for assessing body composition are reported to have good reproducibility compared to the reference method of dual energy absorptiometry (DXA). In the current study, we compared the level of agreement between body composition measured with DXA and skinfold thickness (SFT) in CKD Stage 3 and 4, at 2 occasions, 6 months apart., Methods: Body composition was assessed in 177 Indian patients with CKD Stage 3 and 4 using DXA and anthropometry (SFT). The body fat mass obtained by the 2 methods was compared by paired t-test, intraclass correlation coefficients, regression analysis, and Bland-Altman plots. A linear regression analysis was done to identify the patient-related parameters which would account for the intermethod differences between DXA and SFT., Results: Compared to DXA, SFT underestimated the fat mass at baseline as well as 6 months [DXA vs. SFT at entry: 15.85 kg (95% confidence interval, CI 15.07-16.65) vs. 13.71 kg (95% CI 13.21-14.32), P < .001; at 6 months: 16.13 (95% CI 15.33-16.93) vs. 13.85 (95% CI 13.25-14.45), P < .001]. The intraclass correlation coefficients at entry and 6 months were 0.894 (0.857-0.921) and 0.896 (0.860-0.923), respectively. The intermethod differences between DXA and SFT at baseline and 6 months were comparable: 2.08 kg (95% CI 1.66-2.5) at baseline versus 2.27 kg (95% CI 1.83-2.71) at 6 months, P = 0.200. Gender and body mass index turned out to be the significant predictors of intermethod differences at base line and exit (P < .001)., Conclusions: SFT-based measurements show good reproducibility compared to DXA over a period of 6 months. However, SFT systematically underestimates the fat mass by 2 Kg compared to DXA., (Copyright © 2019 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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30. Pregnane X receptor activation by its natural ligand Ginkgolide-A improves tight junction proteins expression and attenuates bacterial translocation in cirrhosis.
- Author
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Mohandas S and Vairappan B
- Subjects
- Animals, Cytochrome P-450 CYP3A metabolism, Ginkgo biloba, Inflammation metabolism, Interferon-gamma metabolism, Interleukin-6 metabolism, Intestine, Small drug effects, Intestine, Small metabolism, Ligands, Liver drug effects, Liver metabolism, Male, Mice, NF-kappa B metabolism, Plant Extracts pharmacology, Zonula Occludens-1 Protein metabolism, Bacterial Translocation drug effects, Ginkgolides pharmacology, Lactones pharmacology, Liver Cirrhosis metabolism, Pregnane X Receptor metabolism, Tight Junction Proteins metabolism
- Abstract
Background and Aims: Pregnane X receptor (PXR) is a ligand-activated transcription factor and nuclear receptor expressed ubiquitously along gut-liver-axis. Inflammatory bowel disorders have been reported to implicate PXR in maintaining tight junction (TJ) integrity and countering inflammation. However, the hepatoprotective role of PXR activation in soothing bacterial translocation in liver cirrhosis has not been explored. Ginkgolide A (GA), a terpene trilactone from Ginkgo Biloba extract, is a natural ligand of rodent and human PXR. This study aims to investigate the effect of GA in activating PXR and improving associated tight junction integrity and reducing bacterial translocation in gut-liver axis of CCl
4 induced cirrhosis model., Methods: Swiss albino mice were administered with CCl4 (0.5 ml/kg body weight, i.p) in corn oil for 12 weeks at an interval of two times a week. Following ascites induction, mice were randomized & administered 100 mg/kg body weight of GA through oral gavage for 2 weeks. At termination, blood, gut and liver tissues were collected for biochemical and molecular studies., Results: When compared to naïve mice, protein expression of hepatic and small intestinal PXR, CYP3A, ZO-1 and occludin were found to be significantly (p < 0.01) decreased in CCl4 induced cirrhotic mice. Treatment with GA to cirrhotic mice significantly (p < 0.05) induced the expression of both hepatic and small intestinal PXR, CYP3A, ZO-1 and Occludin. Furthermore, increased (p < 0.01) hepatic and small intestinal NFκB was observed in CCl4 induced cirrhotic mice that was significantly (p < 0.05) lowered following GA treatment. Over expression of TLR4/MyD88/NFκB axis and its downstream pro-inflammatory mediators TNF-α, IL6 and IFN-γ were observed in CCl4 induced mice, and these indices were abrogated significantly after GA treatment. Furthermore, significantly increased plasma levels of bacterial translocation markers LBP and procalcitonin were found in CCl4 mice, which were reduced significantly (p < 0.05 & p < 0.0001) after GA treatment., Conclusion: In conclusion, our data supports the hypothesis that, GA treatment to CCl4 induced cirrhotic mice, activated hepatic and small intestinal PXR and diminished inflammation, thereby improving tight junction integrity and attenuating bacterial translocation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2020
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31. Correction of metabolic acidosis improves muscle mass and renal function in chronic kidney disease stages 3 and 4: a randomized controlled trial.
- Author
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Dubey AK, Sahoo J, Vairappan B, Haridasan S, Parameswaran S, and Priyamvada PS
- Subjects
- Acidosis etiology, Acidosis pathology, Administration, Oral, Case-Control Studies, Female, Glomerular Filtration Rate, Humans, Male, Middle Aged, Prognosis, Prospective Studies, Renal Insufficiency, Chronic pathology, Acidosis drug therapy, Renal Insufficiency, Chronic complications, Sodium Bicarbonate administration & dosage
- Abstract
Background: Metabolic acidosis (MA) is associated with a loss of muscle mass and faster deterioration of kidney function in patients with chronic kidney disease (CKD). A few single-centre randomized trials have reported favourable outcomes following correction of MA. Additional good quality evidence on the safety and efficacy of alkali supplementation is required in epidemiologically different patient subsets with CKD., Methods: A single-centre, open-label, randomized, prospective parallel-group study was conducted to assess the effect of correction of MA on body composition and kidney function. A total of 188 patients with CKD stages 3 and 4, with venous bicarbonate levels <22 mEq/L were randomized. The intervention arm received standard care as per Kidney Disease: Improving Global Outcomes (KDIGO) 2012 guidelines along with oral sodium bicarbonate supplementation to maintain venous bicarbonate levels at 24-26 mEq/L, whereas the control group received standard care alone. The mid-arm muscle circumference (MAMC), lean body mass (LBM) and estimated glomerular filtration rate (eGFR) were compared between the groups at the end of 6 months., Results: The intervention arm showed a higher LBM {36.8 kg [95% confidence interval (CI) 36.5-37.1] versus 36 [35.7-36.4]; P = 0.002} and MAMC [22.9 cm (95% CI 22.8-23) versus 22.6 (22.5-22.7); P = 0.001] when compared with the control group. The GFR in the intervention arm was higher [32.74 mL/1.73 m2 (95% CI 31.5-33.9) versus 28.2 (27-29.4); P ≤ 0.001]. A rapid decline in GFR was documented in 39 (41.5%) patients in the control arm and 19 (20.2%) patients in the intervention arm (P = 0.001)., Conclusions: Alkali supplementation to increase venous bicarbonate levels to 24-26 mEq/L is associated with preservation of LBM and kidney function in patients with CKD stages 3 and 4., (© The Author(s) 2018. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)
- Published
- 2020
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32. Resveratrol Restores Neuronal Tight Junction Proteins Through Correction of Ammonia and Inflammation in CCl 4 -Induced Cirrhotic Mice.
- Author
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Vairappan B, Sundhar M, and Srinivas BH
- Subjects
- Aldehydes metabolism, Ammonia blood, Animals, Brain metabolism, Carbon Tetrachloride, Cytokines blood, Inflammation pathology, Liver Cirrhosis blood, Liver Cirrhosis chemically induced, Liver Cirrhosis pathology, Male, Mice, Models, Biological, NF-kappa B metabolism, Neurons drug effects, Nitric Oxide Synthase Type II metabolism, Occludin metabolism, Oxidative Stress drug effects, Resveratrol pharmacology, Water metabolism, Zonula Occludens-1 Protein metabolism, Ammonia metabolism, Inflammation drug therapy, Inflammation metabolism, Liver Cirrhosis drug therapy, Neurons metabolism, Resveratrol therapeutic use, Tight Junction Proteins metabolism
- Abstract
Systemic inflammation and ammonia (hyperammonemia) act synergistically in the pathogenesis of hepatic encephalopathy (HE), the neurobehavioral sequelae of advanced liver disease. In cirrhotic patients, we have recently observed elevated levels of circulating neuronal tight junction (TJ) protein, zonula occludens 1 (ZO-1), reflective of a change to blood-brain barrier (BBB) integrity. Moreover, ZO-1 levels positively correlated with hyperammonemia, although any potential relationship remains unclear. Using a carbon tetrachloride (CCl
4 )-induced mouse model of cirrhosis, we primarily looked to explore the relationship between neuronal TJ protein expression and hyperammonemia. Secondarily, we assessed the potential role of a natural antioxidant, resveratrol, on neuronal TJ protein expression and hyperammonemia. Over 12 weeks, male Swiss mice were randomized (n = 8/group) to either naïve controls or induced cirrhosis, using two doses of intraperitoneal CCl4 (0.5 ml/kg/week). After 12 weeks, naïve and cirrhotic mice were randomized to receive either 2 weeks of par-oral resveratrol (10 mg/kg). Plasma samples were analyzed for ammonia, liver biochemistry (ALT, AST, albumin, and bilirubin), and pro-inflammatory cytokines (TNF-α and IL-1β), and brain tissue for brain water content, TJ protein expression (e.g., ZO-1, claudin 5, and occludin), and tissue oxidative stress and inflammatory markers (NF-κB and iNOS) using western blotting. Compared to naïve mice, cirrhosis significantly increased circulating ammonia, brain water, ALT, AST, TNF-α, IL-1β, 4HNE, NF-κB, and iNOS levels, with a concomitant reduction in all TJ proteins (P < 0.05, respectively). In cirrhotic mice, resveratrol treatment ameliorated these changes significantly (P < 0.05, respectively). Our findings provide evidence for a causal association between hyperammonemia and inflammation in cirrhosis linked to TJ protein alterations, BBB disruption, and HE predilection. Moreover, this is the first report of a potential role for resveratrol as a novel therapeutic approach to managing neurological sequelae complicating cirrhosis.- Published
- 2019
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33. Increased systemic zonula occludens 1 associated with inflammation and independent biomarker in patients with hepatocellular carcinoma.
- Author
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Ram AK, Pottakat B, and Vairappan B
- Subjects
- C-Reactive Protein analysis, Case-Control Studies, Disease Progression, Female, Healthy Volunteers, Humans, Liver Function Tests, Male, Middle Aged, Biomarkers, Tumor blood, Carcinoma, Hepatocellular blood, Liver Neoplasms blood, Zonula Occludens-1 Protein blood
- Abstract
Background: Hepatocellular carcinoma (HCC) is a frequent type of primary liver cancer, and its prevalence is increasing worldwide. Indeed, the underlying molecular mechanism is not well understood. Previous studies have shown evidence that tight junction (TJ) components were correlated with carcinogenesis and tumor development. Our aims were to determine the serum levels of tight junction protein Zonula Occludens (ZO)-1 and an inflammatory marker such as high-sensitive C-reactive protein (hs-CRP) in HCC patients compared to healthy volunteers and also to identify the association between ZO-1 and inflammation in HCC., Methods: Thirty HCC patients and 30 healthy volunteers were recruited in the current study. Clinical data regarding child class, BCLC staging, the number of lesions, tumor size, absence or presence of metastasis, cirrhosis and hepatitis infection were also collected in HCC patients. Plasma ZO-1 and serum hsCRP were analyzed by EIA and ELISA respectively and biochemical parameters by autoanalyser (AU680 Beckman Coulter, USA). Furthermore, hepatic ZO-1 protein expression and tissue localization were examined., Results: Compared to healthy individuals, the serum levels of bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT) and alkaline phosphatase (ALP) were elevated significantly (P < 0.0001) whilst serum albumin level was significantly (P < 0.0001) decreased in HCC patients. Furthermore, tight junction protein ZO-1 concentration was significantly elevated in HCC patients compared to control subjects (648 ± 183.8 vs. 396.4 ± 135.8 pg/ml, respectively; P < 0.0001). Serum hsCRP level was also significantly increased in HCC patients compared to control subjects (17.25 ± 3.57 vs. 5.54 ± 2.62 mg/L, respectively; P < 0.0001). Moreover, decreased protein expression of ZO-1 was found in liver tissue obtained from HCC patients., Conclusion: Our findings show for the first time that the systemic concentration of ZO-1 was significantly elevated in HCC patients and is positively correlated with inflammatory markers. Thus, the current study showing evidence that inflammation promotes plasma ZO-1 concentration and raises the possibility that it could be used as a potential diagnostic biomarker for HCC progression.
- Published
- 2018
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34. Elevated systemic zonula occludens 1 is positively correlated with inflammation in cirrhosis.
- Author
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Karthikeyan A, Mohan P, Chinnakali P, and Vairappan B
- Subjects
- Adolescent, Adult, Biomarkers blood, Cross-Sectional Studies, Humans, Middle Aged, Nitric Oxide blood, Young Adult, Fibrosis blood, Inflammation blood, Zonula Occludens-1 Protein blood
- Abstract
Background/aim: It has been well established that disruption of the intestinal barrier function and increased intestinal permeability contribute to endotoxemia and associated liver injury in patients with cirrhosis. However, the relationship between systemic inflammation and tight junction protein in cirrhosis remain unidentified. The aim of this study was to assess and compare the blood concentrations of ZO-1 with systemic hsCRP in patients with cirrhosis and healthy individuals., Methods: 30 cirrhotic patients and 30 healthy individuals were enrolled in the study. Blood ZO-1 and hsCRP were measured by ELISA and biochemical parameters by AU680 Beckman Coulter (USA) autoanalyser., Results: The serum ALT, AST, bilirubin, gamma GT, ALP and ammonia were significantly (P < 0.0001) elevated whilst serum albumin concentration was decreased in cirrhotic patients when compared to healthy individuals. Systemic tight junction protein ZO-1 concentration [590.0 ± 32.79 vs. 349.9 ± 18.76 pg/ml, respectively; P < 0.0001] and hsCRP [10.50 ± 1.05 vs 5.31 ± 0.65 mg/L, respectively; P < 0.001] were significantly elevated in patients with cirrhosis compared to controls. Significant positive correlation was found between increased ZO-1 and hsCRP (r = 0.2680 P < 0.01)., Conclusion: Our results suggested that increased systemic ZO-1 concentration was associated with inflammation in cirrhosis. Thus, elevated blood ZO-1 levels could be a prognostic marker of cirrhotic patients with intestinal TJ disruption on the background of inflammation., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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35. Role of pregnane X-receptor in regulating bacterial translocation in chronic liver diseases.
- Author
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Mohandas S and Vairappan B
- Abstract
Bacterial translocation (BT) has been impeccably implicated as a driving factor in the pathogenesis of a spectrum of chronic liver diseases (CLD). Scientific evidence accumulated over the last four decades has implied that the disease pathologies in CLD and BT are connected as a loop in the gut-liver axis and exacerbate each other. Pregnane X receptor (PXR) is a ligand-activated transcription factor and nuclear receptor that is expressed ubiquitously along the gut-liver-axis. PXR has been intricately associated with the regulation of various mechanisms attributed in causing BT. The importance of PXR as the mechanistic linker molecule in the gut-liver axis and its role in regulating bacterial interactions with the host in CLD has not been explored. PubMed was used to perform an extensive literature search using the keywords PXR and bacterial translocation, PXR and chronic liver disease including cirrhosis. In an adequate expression state, PXR acts as a sensor for bile acid dysregulation and bacterial derived metabolites, and in response shapes the immune profile beneficial to the host. Activation of PXR could be therapeutic in CLD as it counter-regulates endotoxin mediated inflammation and maintains the integrity of intestinal epithelium. This review mainly focuses PXR function and its regulation in BT in the context of chronic liver diseases., Competing Interests: Conflict-of-interest statement: None declared.
- Published
- 2017
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36. Ammonia toxicity: from head to toe?
- Author
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Dasarathy S, Mookerjee RP, Rackayova V, Rangroo Thrane V, Vairappan B, Ott P, and Rose CF
- Subjects
- Animals, Brain pathology, Brain Chemistry, Hepatic Encephalopathy, Humans, Hyperammonemia metabolism, Hyperammonemia pathology, Muscle, Skeletal pathology, Ammonia metabolism, Ammonia toxicity
- Abstract
Ammonia is diffused and transported across all plasma membranes. This entails that hyperammonemia leads to an increase in ammonia in all organs and tissues. It is known that the toxic ramifications of ammonia primarily touch the brain and cause neurological impairment. However, the deleterious effects of ammonia are not specific to the brain, as the direct effect of increased ammonia (change in pH, membrane potential, metabolism) can occur in any type of cell. Therefore, in the setting of chronic liver disease where multi-organ dysfunction is common, the role of ammonia, only as neurotoxin, is challenged. This review provides insights and evidence that increased ammonia can disturb many organ and cell types and hence lead to dysfunction.
- Published
- 2017
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37. Endothelial dysfunction in cirrhosis: Role of inflammation and oxidative stress.
- Author
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Vairappan B
- Abstract
This review describes the recent developments in the pathobiology of endothelial dysfunction (ED) in the context of cirrhosis with portal hypertension and defines novel strategies and potential targets for therapy. ED has prognostic implications by predicting unfavourable early hepatic events and mortality in patients with portal hypertension and advanced liver diseases. ED characterised by an impaired bioactivity of nitric oxide (NO) within the hepatic circulation and is mainly due to decreased bioavailability of NO and accelerated degradation of NO with reactive oxygen species. Furthermore, elevated inflammatory markers also inhibit NO synthesis and causes ED in cirrhotic liver. Therefore, improvement of NO availability in the hepatic circulation can be beneficial for the improvement of endothelial dysfunction and associated portal hypertension in patients with cirrhosis. Furthermore, therapeutic agents that are identified in increasing NO bioavailability through improvement of hepatic endothelial nitric oxide synthase (eNOS) activity and reduction in hepatic asymmetric dimethylarginine, an endogenous modulator of eNOS and a key mediator of elevated intrahepatic vascular tone in cirrhosis would be interesting therapeutic approaches in patients with endothelial dysfunction and portal hypertension in advanced liver diseases.
- Published
- 2015
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38. Characterisation of temporal microglia and astrocyte immune responses in bile duct-ligated rat models of cirrhosis.
- Author
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Wright GA, Sharifi Y, Newman TA, Davies N, Vairappan B, Perry HV, and Jalan R
- Subjects
- Animals, Brain immunology, Calcium-Binding Proteins metabolism, Consciousness Monitors, Corpus Callosum metabolism, Glial Fibrillary Acidic Protein metabolism, HSP27 Heat-Shock Proteins metabolism, Immunohistochemistry, Interleukin-1beta metabolism, Male, Microfilament Proteins metabolism, Nitric Oxide Synthase Type II metabolism, Rats, Rats, Sprague-Dawley, Transforming Growth Factor beta metabolism, Astrocytes immunology, Biomarkers metabolism, Brain metabolism, Liver Cirrhosis, Experimental immunology, Microglia immunology
- Abstract
Background & Aims: Microglia and astrocyte related pro-inflammatory responses are thought to underpin cerebral sequelae of acute liver failure. Conversely, despite background pro-inflammatory responses in cirrhosis, overt brain swelling and coma associated with acute-on-chronic liver failure, is infrequent unless precipitated (e.g. sepsis). Moreover in other chronic neurodegenerative disorders and sepsis, the brain is protected from recurrent microbial insults by compensatory microglial-associated immune responses. To characterise longitudinal cerebral immune responses in a bile duct-ligated (BDL) rat model of cirrhosis., Method: Rats underwent BDL or sham operation before sacrifice at either 1-day, 1, 2 and 4 weeks post-surgery. We analysed consciousness, brain water, biochemistry and immunohistochemistry to assess activation of microglia (ED-1, OX6 and Iba-1), astrocytes (Glial fibrillary acidic protein - GFAP), cellular stress (Heat shock protein - Hsp 25) and pro-inflammatory mediator expression (inducible nitric oxide synthase (iNOS), interleukin-1beta (IL-1β) and tumour growth factor-beta (TGF-β))., Results: BDL significantly increased ammonia and bilirubin (P < 0.01 respectively). The classical microglial markers OX6, ED1 and Iba-1 and pro-inflammatory IL-1β and iNOS were not significantly increased. However, the alternative microglial marker and regulatory cytokine TGF-β was elevated from day 1 to 4 weeks post-BDL. GFAP expression was significantly increased in corpus callosum in all groups. In BDL rats, Hsp 25 was also increased in the corpus callosum, peaking at 2 weeks., Conclusion: BDL triggers early alternative, but not classical, microglial activation. There was a correlation between astrocyte activation and cellular stress. These findings indicate early cerebral immune responses, which may be associated with immune tolerance to further challenge., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2014
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39. Reduction in hyperammonaemia by ornithine phenylacetate prevents lipopolysaccharide-induced brain edema and coma in cirrhotic rats.
- Author
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Wright G, Vairappan B, Stadlbauer V, Mookerjee RP, Davies NA, and Jalan R
- Subjects
- Animals, Antibodies, Monoclonal administration & dosage, Bile Ducts surgery, Blotting, Western, Body Water metabolism, Brain metabolism, Brain Edema etiology, Cytokines blood, Cytokines metabolism, Hyperammonemia blood, Hyperammonemia complications, Infliximab, Injections, Intraperitoneal, Interleukin-6 blood, Ligation, Lipopolysaccharides toxicity, Liver Cirrhosis complications, Ornithine administration & dosage, Ornithine pharmacology, Rats, Tumor Necrosis Factor-alpha blood, Antibodies, Monoclonal pharmacology, Brain drug effects, Brain Edema prevention & control, Hyperammonemia metabolism, Liver Cirrhosis metabolism, Ornithine analogs & derivatives
- Abstract
Objective: In liver failure, inflammation synergistically exacerbates the deleterious cerebral effects of ammonia. The aims were to test whether treatment with the ammonia-lowering agent ornithine phenylacetate (OP) and/or anti-TNF-α (infliximab) prevent the deleterious brain consequences of lipopolysaccharide (LPS) in cirrhotic rats., Design: Rats 4 weeks following bile duct-ligation (BDL), sham-operation (sham) and/or 7 days hyperammonemic feed (HD), were randomized to receive LPS (1 mg/kg) or saline, and treatment with either 3 days intraperitoneal injections of OP (0.6 g/kg) and/or infliximab, 10 mg/kg. Animals were sacrificed at coma stages or at 3 h., Results: In sham rats, both HD and LPS increased brain water, with an increase in ammonia in the former and brain cytokines in the latter but with no effect on consciousness. BDL + HD rats caused significantly higher plasma ammonia, TNF-α and IL-6 levels compared to sham. LPS significantly worsened coma stage, increased brain water and plasma and brain TNF-α. OP significantly delayed LPS-induced progression to coma stages (P < 0.009), reduced arterial ammonia and brain water (P < 0.001 and P < 0.01 respectively), which was associated with a significant reduction in cytokines. Infliximab significantly reduced plasma and brain cytokines, but not brain water. OP + infliximab attenuated increase in brain water and delayed occurrence of coma, which was not different to OP alone. In BDL rats, OP reduced the expression of brain iNOS and NFκB., Conclusion: Reduction in ammonia with OP in cirrhotic rats prevents LPS-induced brain edema and delays coma, suggesting that ammonia may prime the brain to the deleterious effect of LPS, possibly through effects on iNOS and NFκB related mechanisms., (© 2011 John Wiley & Sons A/S.)
- Published
- 2012
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40. Role of aquaporin-4 in the development of brain oedema in liver failure.
- Author
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Wright G, Soper R, Brooks HF, Stadlbauer V, Vairappan B, Davies NA, Andreola F, Hodges S, Moss RF, Davies DC, and Jalan R
- Subjects
- Animals, Blotting, Western, Brain Edema pathology, Disease Models, Animal, Frontal Lobe blood supply, Frontal Lobe metabolism, Frontal Lobe pathology, Humans, Hyperammonemia complications, Hyperammonemia metabolism, Male, Microscopy, Immunoelectron, Rats, Rats, Sprague-Dawley, Rats, Wistar, Sepsis complications, Sepsis metabolism, p38 Mitogen-Activated Protein Kinases metabolism, Aquaporin 4 metabolism, Brain Edema etiology, Brain Edema metabolism, Liver Failure complications, Liver Failure metabolism
- Abstract
Background & Aims: Liver failure is associated with progressive cytotoxic brain oedema (astrocyte swelling), which underlies hepatic encephalopathy (HE). Ammonia and superimposed inflammation are key synergistic factors in HE, but the mechanism(s) involved remain unknown. We aimed to determine whether aquaporin-4 (AQP4), an astrocyte endfeet bi-directional water channel, is associated with the brain oedema of HE., Method: Rats (n=60) received sham-operation (sham), 5 days hyperammonaemia-inducing diet (HD), galactosamine (GALN) induced acute liver failure (ALF), 4 weeks bile duct-ligation (BDL) induced cirrhosis, or caecal ligation and puncture (CLP), a 24h model of bacterial peritonitis. Rats from every group (except CLP) were randomised to receive intraperitoneal injections of lipopolysaccharide (LPS; 1mg/kg) or saline, prior to termination 3h later. Brain water, AQP4 protein expression (western blot) and AQP4 localisation by immunogold electron microscopy were investigated., Results: Significant hyperammonaemia was observed in saline-injected BDL (p<0.05), GALN (p<0.01), and HD (p<0.01), compared to sham rats. LPS injection did not affect arterial ammonia or plasma biochemistry in any of the treatment groups. Increased brain water was observed in saline-injected GALN (p<0.05), HD (p<0.01), and CLP (p<0.001) compared to sham rats. Brain water was numerically increased in BDL rats, but this failed to reach significance (p=0.09). LPS treatment further increased oedema significantly in all treatment groups (p<0.05, respectively). AQP4 expression was significantly increased in saline-injected BDL (p<0.05), but not other treatment groups, compared to sham rats. Membrane polarisation was maintained in BDL rats., Conclusion: The results suggest that AQP4 is not directly associated with the development of brain oedema in liver failure, hyperammonaemia, or sepsis. In cirrhosis, there is increased AQP4 protein expression, but membrane polarisation, is maintained, possibly in a compensatory attempt to limit severe brain oedema., (Copyright 2010. Published by Elsevier B.V.)
- Published
- 2010
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41. The puzzle of endothelial nitric oxide synthase dysfunction in portal hypertension: The missing piece?
- Author
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Mookerjee RP, Vairappan B, and Jalan R
- Published
- 2007
- Full Text
- View/download PDF
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