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Health-related quality of life and associated factors among COVID-19 individuals managed with indian traditional medicine: A cross-sectional study from south India. CLINICAL EPIDEMIOLOGY AND GLOBAL HEALTH 2023; 20:101250. [PMID: 36816535 PMCID: PMC9922434 DOI: 10.1016/j.cegh.2023.101250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 01/11/2023] [Accepted: 02/07/2023] [Indexed: 02/15/2023] Open
Abstract
Introduction Coronavirus disease-2019 (COVID-19) had a multidimensional impact on human life. It affects the health-related quality of life (HRQoL) which is a perceived measure of physical and mental health. We estimated the EuroQol utility value for COVID-19 and the associated factors for those managed at Siddha COVID care centres in Tamil Nadu. Methods A cross-sectional study was conducted by a telephonic interview of 2000 randomly selected COVID-19 adults tested positive during June 2020 to Jan 2021. We collected sociodemographic, clinical and EQ-5D-5L profile. Mean EQ-5D-5L summary utility values and EQ-VAS scores were estimated. Multivariate regression was used to examine the factors associated with EQ-5D-5L. Study protocol was approved by the Institutional ethics committee of Government Siddha Medical College, Chennai (GSMC-CH-3401/ME-2/050/2021). The committee waived the written informed consent considering the pandemic situation of emerging infectious diseases. Results We interviewed 1047 participants. Of the total 68% were males with the median age (IQR) of 38 (29-51) years. The mean EQ-5D-5L utility score and EQ-VAS scores are 0.98 ± 0.05 and 92.14 ± 0.39 respectively. COVID-19 asymptomatic group reported a mean utility score of 0.99 ± 0.03 which is relatively more than the symptomatic group (0.97 ± 0.06),. EQ-VAS score was also reported high among the asymptomatic (95.45 ± 5.95) than the symptomatic (91.40 ± 8.69COVID-19. Conclusion The severity of illness and the comorbidity are significantly associated with a low HRQoL of COVID-19 patients.
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Analysing the practice of ancient Tamil traditional medicine in management of oral diseases:
a survey of Siddha practioners in Chennai. JOURNAL OF COMPLEMENTARY MEDICINE RESEARCH 2022. [DOI: 10.5455/jcmr.2022.13.04.29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Background:
Siddha is an ancient Indian traditional medicine system that originated in Tamil Nadu and is known to the world as a safe and effective alternative to western medicine. Based on medicinal alchemy, it strives to impart power and longevity to people. It has applications in a wide range of human ailments including dental diseases. There is need for research in the use of Siddha medicine in dentistry. Our study aims to assess the knowledge, awareness and practice of dentistry in Siddha practitioners in Chennai, India.
Methods: Standardized and validated questionnaire to assess the knowledge, awareness and practice of dentistry in Siddha practitioners was employed to random practitioners of Central Siddha Institute, Chennai. We assessed their attitude towards oral diseases, treatment methodology and to determine the types and parts of herbs used for management of oral diseases.
Results and conclusions: 93 professionals provided valid responses. Pertinent data was obtained on the most common dental complaints of patients, the common dental diagnoses, various plants used, the medicinal part of the plants, the mechanism of action, the mode of preparation, use of metals and preservatives etc. This study, being one of the first in eliciting unique responses from Siddha practitioners regarding dentistry, could pioneer further research in developing safe and effective traditional therapies for dental disorders.
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Interactions between calcium and phosphorus in the regulation of the production of fibroblast growth factor 23 in vivo. Am J Physiol Endocrinol Metab 2013; 304:E310-20. [PMID: 23233539 PMCID: PMC3566433 DOI: 10.1152/ajpendo.00460.2012] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 12/04/2012] [Indexed: 11/22/2022]
Abstract
Calcium and phosphorus homeostasis are highly interrelated and share common regulatory hormones, including FGF23. However, little is known about calcium's role in the regulation of FGF23. We sought to investigate the regulatory roles of calcium and phosphorus in FGF23 production using genetic mouse models with targeted inactivation of PTH (PTH KO) or both PTH and the calcium-sensing receptor (CaSR; PTH-CaSR DKO). In wild-type, PTH KO, and PTH-CaSR DKO mice, elevation of either serum calcium or phosphorus by intraperitoneal injection increased serum FGF23 levels. In PTH KO and PTH-CaSR DKO mice, however, increases in serum phosphorus by dietary manipulation were accompanied by severe hypocalcemia, which appeared to blunt stimulation of FGF23 release. Increases in dietary phosphorus in PTH-CaSR DKO mice markedly decreased serum 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] despite no change in FGF23, suggesting direct regulation of 1,25(OH)(2)D(3) synthesis by serum phosphorus. Calcium-mediated increases in serum FGF23 required a threshold level of serum phosphorus of about 5 mg/dl. Analogously, phosphorus-elicited increases in FGF23 were markedly blunted if serum calcium was less than 8 mg/dl. The best correlation between calcium and phosphorus and serum FGF23 was found between FGF23 and the calcium × phosphorus product. Since calcium stimulated FGF23 production in the PTH-CaSR DKO mice, this effect cannot be mediated by the full-length CaSR. Thus the regulation of FGF23 by both calcium and phosphorus appears to be fundamentally important in coordinating the serum levels of both mineral ions and ensuring that the calcium × phosphorus product remains within a physiological range.
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Autoimmune hypocalciuric hypercalcemia unresponsive to glucocorticoid therapy in a patient with blocking autoantibodies against the calcium-sensing receptor. J Clin Endocrinol Metab 2011; 96:672-80. [PMID: 21159843 PMCID: PMC3047232 DOI: 10.1210/jc.2010-1739] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 11/04/2010] [Indexed: 12/24/2022]
Abstract
CONTEXT Autoantibodies directed against the calcium-sensing receptor (CaSR) have been reported in several individuals with various autoimmune disorders and PTH-mediated hypercalcemia. Previously, glucocorticoid treatment has been shown to decrease the CaSR autoantibody titers and normalize the hypercalcemia in a patient with autoimmune hypocalciuric hypercalcemia (AHH). OBJECTIVE The objective of the study was to evaluate a patient with AHH for the presence of blocking autoantibodies against the CaSR and to monitor her biochemical and serological responses to a trial of glucocorticoid therapy. RESULTS Glucocorticoid treatment had no effect on serum total or ionized calcium concentration or serum PTH levels, all of which remained at higher than normal levels. In contrast, on prednisone, urinary calcium excretion increased from overtly hypocalciuric levels to normal values. Anti-CaSR autoantibodies were detected at similar levels in the patient's serum before, during, and after glucocorticoid treatment. Functional testing of these antibodies showed that they inhibited the stimulatory effect of extracellular Ca(2+) on ERK1/2 but did not suppress the calcium-induced accumulation of inositol-1-phosphate. CONCLUSIONS We report a patient with AHH with frankly elevated PTH levels who was found to have autoantibodies against the CaSR. The hypercalcemia and CaSR autoantibody titers failed to respond to glucocorticoid therapy, unlike a previously reported patient with similar clinical and biochemical features. The anti-CaSR antibody-mediated inhibition of CaSR-stimulated ERK1/2 activity, but not of inositol-1-phosphate accumulation, suggests that ERK1/2 may mediate, at least in part, the regulation of PTH secretion and urinary calcium excretion by the CaSR.
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The calcium-sensing receptor (CaSR) defends against hypercalcemia independently of its regulation of parathyroid hormone secretion. Am J Physiol Endocrinol Metab 2009; 297:E915-23. [PMID: 19797241 PMCID: PMC2763782 DOI: 10.1152/ajpendo.00315.2009] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The calcium-sensing receptor (CaSR) controls parathyroid hormone (PTH) secretion, which, in turn, via direct and indirect actions on kidney, bone, and intestine, maintains a normal extracellular ionized calcium concentration (Ca(2+)(o)). There is less understanding of the CaSR's homeostatic importance outside of the parathyroid gland. We have employed single and double knockout mouse models, namely mice lacking PTH alone (CaSR(+/+) PTH(-/-), referred to as C(+)P(-)), lacking both CaSR and PTH (CaSR(-/-) PTH(-/-), C(-)P(-)) or wild-type (CaSR(+/+) PTH(+/+), C(+)P(+)) mice to study CaSR-specific functions without confounding CaSR-mediated changes in PTH. The mice received three hypercalcemic challenges: an oral Ca(2+) load, injection or constant infusion of PTH via osmotic pump, or a phosphate-deficient diet. C(-)P(-) mice show increased susceptibility to developing hypercalcemia with all three challenges compared with the other two genotypes, whereas C(+)P(-) mice defend against hypercalcemia similarly to C(+)P(+) mice. Reduced renal Ca(2+) clearance contributes to the intolerance of the C(-)P(-) mice to Ca(2+) loads, as they excrete less Ca(2+) at any given Ca(2+)(o) than the other two genotypes, confirming the CaSR's direct role in regulating renal Ca(2+) handling. In addition, C(+)P(+) and C(+)P(-), but not C(-)P(-), mice showed increases in serum calcitonin (CT) levels during hypercalcemia. The level of 1,25(OH)(2)D(3) in C(-)P(-) mice, in contrast, was similar to those in C(+)P(-) and C(+)P(+) mice during an oral Ca(2+) load, indicating that increased 1,25(OH)(2)D(3) production cannot account for the oral Ca(2+)-induced hypercalcemia in the C(-)P(-) mice. Thus, CaSR-stimulated PTH release serves as a "floor" to defend against hypocalcemia. In contrast, high-Ca(2+)(o)-induced inhibition of PTH is not required for a robust defense against hypercalcemia, at least in mice, whereas high-Ca(2+)(o)-stimulated, CaSR-mediated CT secretion and renal Ca(2+) excretion, and perhaps other factors, serve as a "ceiling" to limit hypercalcemia resulting from various types of hypercalcemic challenges.
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The full-length calcium-sensing receptor dampens the calcemic response to 1alpha,25(OH)2 vitamin D3 in vivo independently of parathyroid hormone. Am J Physiol Renal Physiol 2009; 297:F720-8. [PMID: 19474191 DOI: 10.1152/ajprenal.00164.2009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
1Alpha,25(OH)(2) vitamin D(3) [1,25(OH)(2)D(3)] increases serum Ca(2+) concentration in vivo, an action counteracted by activation of the Ca(2+)-sensing receptor (CaSR), which decreases parathyroid hormone (PTH) secretion and increases renal Ca(2+) excretion. Relatively little is known of the role the CaSR plays in this response through its potentially direct actions in kidney, gut, and bone independently of PTH. We report PTH-independent roles of the CaSR in modulating the response to exogenous 1,25(OH)(2)D(3) in mice with targeted disruption of both the CaSR and PTH genes (C(-)P(-)) compared with that in mice with disruption of the PTH gene alone (C(+)P(-)) or wild-type mice (C(+)P(+)). After intraperitoneal injection of 0.5 ng/g body wt 1,25(OH)(2)D(3), peak calcemic responses were observed at 24 h in all three genotypes in association with 1) a greater increase in serum Ca(2+) in C(-)P(-) mice than in the other genotypes on a Ca(2+)-replete diet that was attenuated by a Ca(2+)-deficient diet and pamidronate, 2) increased urinary Ca(2+)-to-creatinine ratios (UCa/Cr) in the C(+)P(-) and C(+)P(+) mice but a lowered ratio in the C(-)P(-) mice on a Ca(2+)-replete diet, and 3) no increase in calcitonin (CT) secretion in the C(+)P(+) and C(+)P(-) mice and a small increase in the C(-)P(-) mice. PTH deficiency had the anticipated effects on the expression of key genes involved in Ca(2+) transport at baseline in the duodenum and kidney, and injection of 1,25(OH)(2)D(3) increased gene expression 8 h later. However, the changes in the genes evaluated did not fully explain the differences in serum Ca(2+) seen among the genotypes. In conclusion, mice lacking the full-length CaSR have increased sensitivity to the calcemic action of 1,25(OH)(2)D(3) in the setting of PTH deficiency. This is principally from enhanced 1,25(OH)(2)D(3)-mediated gut Ca(2+) absorption and decreased renal Ca(2+) excretion, without any differences in bone-related release of Ca(2+) or CT secretion among the three genotypes that could explain the differences in their calcemic responses.
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Regulation of the selenoprotein SelS by glucose deprivation and endoplasmic reticulum stress - SelS is a novel glucose-regulated protein. FEBS Lett 2004; 563:185-90. [PMID: 15063746 DOI: 10.1016/s0014-5793(04)00296-0] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2004] [Revised: 02/19/2004] [Accepted: 03/06/2004] [Indexed: 01/11/2023]
Abstract
SelS is a newly identified selenoprotein and its gene expression is up-regulated in the liver of Psammomys obesus after fasting. We have examined whether SelS is regulated by glucose deprivation and endoplasmic reticulum (ER) stress in HepG2 cells. Glucose deprivation and the ER stress inducers tunicamycin and thapsigargin increased SelS gene expression and protein content several-fold in parallel with glucose-regulated protein 78. The overexpression of SelS increased Min6 cell resistance to oxidative stress-induced toxicity. These results indicate that SelS is a novel member of the glucose-regulated protein family and its function is related to the regulation of cellular redox balance.
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MESH Headings
- Amino Acid Sequence
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/pathology
- Cell Line, Tumor
- Cell Survival
- Endoplasmic Reticulum/drug effects
- Endoplasmic Reticulum/physiology
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation, Neoplastic
- Genes, Reporter
- Glucose/metabolism
- HSP70 Heat-Shock Proteins
- Humans
- Hydrogen Peroxide/pharmacology
- Luciferases/genetics
- Luciferases/metabolism
- Membrane Proteins
- Molecular Sequence Data
- Mutagenesis, Insertional
- Oxidants/pharmacology
- Promoter Regions, Genetic
- Proteins/chemistry
- Proteins/genetics
- Proteins/metabolism
- RNA, Messenger/metabolism
- Selenoproteins
- Sequence Homology, Amino Acid
- Stress, Physiological/metabolism
- Thapsigargin/pharmacology
- Time Factors
- Tunicamycin/pharmacology
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Abstract
Increased hepatic glucose output and decreased glucose utilization are implicated in the development of type 2 diabetes. We previously reported that the expression of a novel gene, Tanis, was upregulated in the liver during fasting in the obese/diabetic animal model Psammomys obesus. Here, we have further studied the protein and its function. Cell fractionation indicated that Tanis was localized in the plasma membrane and microsomes but not in the nucleus, mitochondria, or soluble protein fraction. Consistent with previous gene expression data, hepatic Tanis protein levels increased more significantly in diabetic P. obesus than in nondiabetic controls after fasting. We used a recombinant adenovirus to increase Tanis expression in hepatoma H4IIE cells and investigated its role in metabolism. Tanis overexpression reduced glucose uptake, basal and insulin-stimulated glycogen synthesis, and glycogen content and attenuated the suppression of PEPCK gene expression by insulin, but it did not affect insulin-stimulated insulin receptor phosphorylation or triglyceride synthesis. These results suggest that Tanis may be involved in the regulation of glucose metabolism, and increased expression of Tanis could contribute to insulin resistance in the liver.
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Abstract
DNA-based approaches to the discovery of genes contributing to the development of type 2 diabetes have not been very successful despite substantial investments of time and money. The multiple gene-gene and gene-environment interactions that influence the development of type 2 diabetes mean that DNA approaches are not the ideal tool for defining the etiology of this complex disease. Gene expression-based technologies may prove to be a more rewarding strategy to identify diabetes candidate genes. There are a number of RNA-based technologies available to identify genes that are differentially expressed in various tissues in type 2 diabetes. These include differential display polymerase chain reaction (ddPCR), suppression subtractive hybridization (SSH), and cDNA microarrays. The power of new technologies to detect differential gene expression is ideally suited to studies utilizing appropriate animal models of human disease. We have shown that the gene expression approach, in combination with an excellent animal model such as the Israeli sand rat (Psammomys obesus), can provide novel genes and pathways that may be important in the disease process and provide novel therapeutic approaches. This paper will describe a new gene discovery, beacon, a novel gene linked with energy intake. As the functional characterization of novel genes discovered in our laboratory using this approach continues, it is anticipated that we will soon be able to compile a definitive list of genes that are important in the development of obesity and type 2 diabetes.
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Abstract
Here we describe a novel protein, which we have named Tanis, that is implicated in type 2 diabetes and inflammation. In Psammomys obesus, a unique polygenic animal model of type 2 diabetes and the metabolic syndrome, Tanis is expressed in the liver in inverse proportion to circulating glucose (P = 0.010) and insulin levels (P = 0.004) and in direct proportion with plasma triglyceride concentrations (P = 0.007). Hepatic Tanis gene expression was markedly increased (3.1-fold) after a 24-h fast in diabetic but not in nondiabetic P. obesus. In addition, glucose inhibited Tanis gene expression in cultured hepatocytes (P = 0.006) as well as in several other cell types (P = 0.001-0.011). Thus, Tanis seems to be regulated by glucose and is dysregulated in the diabetic state. Yeast-2 hybrid screening identified serum amyloid A (SAA), an acute-phase inflammatory response protein, as an interacting protein of Tanis, and this was confirmed by Biacore experiments. SAA and other acute-phase proteins have been the focus of recent attention as risk factors for cardiovascular disease, and we contend that Tanis and its interaction with SAA may provide a mechanistic link among type 2 diabetes, inflammation, and cardiovascular disease.
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Abstract
Although cocaine has a fascinating and complex medicinal history in man, its natural function in plants is unknown. The present studies demonstrate that cocaine exerts insecticidal effects at concentrations which occur naturally in coca leaves. Unlike its known action on dopamine reuptake in mammals, cocaine's pesticidal effects are shown to result from a potentiation of insect octopaminergic neurotransmission. Amine-reuptake blockers of other structural classes also exert pesticidal activity with a rank order of potency distinct from that known to affect vertebrate amine transporters. These findings suggest that cocaine functions in plants as a natural insecticide and that octopamine transporters may be useful sites for targeting pesticides with selectivity toward invertebrates.
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Abstract
Bovine heart mitochondrial coupling factor B was isolated and purified to homogeneity in its active form. The amino-terminal amino acid sequence of the alkylated protein was determined. Two chains with exactly the same sequence except for the presence of an additional Phe at the amino-terminus on one of them were obtained. The 55 amino acid sequence appears to be largely hydrophilic with several charged amino acid residues. This sequence showed no homology with the E. coli unc operon, oligomycin sensitivity conferring protein, or coupling factor 6 or any protein in the data base.
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Abstract
An octopamine receptor photoaffinity probe was used to label membranes from the light organs of Photinus pyralis, a tissue highly enriched in octopamine receptors. Labeling was concentrated in a glycoprotein of 75 +/- 2 kDa with lesser labeling of a 79 +/- 2 kDa component. Labeling could be displaced by prior incubation with octopamine, mianserin, cyproheptadine, phentolamine or propranolol, with a relative potency that correlated with the ability of these same agents to modulate light organ octopamine-sensitive adenylate cyclase. The 75 kDa binding protein was isolated and its N-terminal amino acid sequence was determined.
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Coupling factor B is a component of the Fo proton channel of mitochondrial H+-ATPase. J Biol Chem 1987; 262:3007-10. [PMID: 2434494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Repeated extraction of bovine heart submitochondrial particles with ammonia and EDTA (AE) yields a preparation that is highly deficient in coupling factor B (FB). The activity of the thrice extracted particle (AE-P3) in ATP-driven NAD+ reduction by succinate and the 32Pi-ATP exchange activity were substantially stimulated, 8-fold and 5-fold, respectively, by purified FB. To decrease the basal activity of the particle further, the residual FB in AE-P3 was inactivated by treatment with the -SH reagent, 4-vinylpyridine. The resulting particle was depleted of F1 by treatment with 3.5 M NaBr. This particle was incorporated into asolectin liposomes alone and in the presence of added FB. Passive proton conduction in the FB-deficient proteoliposomes was negligible and restored in the presence of FB. The H+ conductance was inhibited extensively by oligomycin and partially by F1-ATPase. The results show absolute dependence on FB for functioning of the FO proton channel.
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?-Glucosidase ofPenicillium funiculosum. II. Properties and mycelial binding. Biotechnol Bioeng 1985; 27:786-91. [DOI: 10.1002/bit.260270606] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
Two monoclonal antibodies (MAb I and IV) have been prepared which showed high and specific reactions towards bovine heart mitochondrial coupling factor B (FB). Both have been identified as sub-type IgG1 of mouse immunoglobulins. MAb I reacts with purified and functionally active FB, alkylated or oxidized forms of FB and even with peptides formed on digestion of FB with trypsin. When used together, MAb I and IV reacted with FB in immunoblots of normal and urea treated samples of mitochondria, submitochondrial particles, ammonia-EDTA extracted particles, and H+-ATPase. Both MAbs inhibited FB-stimulated ATP-dependent reverse electron flow activity when FB was incubated with the antibody either before or after its addition to FB-deficient AE-particles. Reactivity of MAb I towards FB declined upon exposure of FB to guanidine HC1 while reactivity of MAb IV remained unaltered.
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Evidence for the involvement of coupling factor B in the H+ channel of the mitochondrial H+-ATPase. Proc Natl Acad Sci U S A 1984; 81:1371-4. [PMID: 6143319 PMCID: PMC344835 DOI: 10.1073/pnas.81.5.1371] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Membrane energization by ATP has been measured in vesicles containing purified bovine heart mitochondrial H+-ATPase (ATP synthase) with the voltage-sensitive dye oxonol VI. The dithiol chelator, Cd2+, and the thiol oxidant, copper o-phenanthroline, produced discharge of the membrane potential when added at the steady state and inhibited its establishment when added prior to energization by ATP. These effects, which were reversed by dithiothreitol, were not accompanied by an increase in the nonspecific H+ permeability of the membrane. Passive H+ conduction in proteoliposomes containing F0 (hydrophobic segment of ATP synthase) was assayed by the quenching of 9-aminoacridine fluorescence after establishing a K+ diffusion potential. This conductance was blocked by Cd2+, an inhibitor of coupling factor B (FB). Labeling of F0 with 115Cd2+ at the concentrations that inhibited the F0 conductance followed by gel electrophoresis yielded a single radioactive band with a molecular weight corresponding to FB, the presence of which in the F0 preparation was confirmed by immunoblot staining. The data offer strong evidence that FB is an essential component of the H+ channel of F0, because H+ conduction through the channel is inhibited by chemical modification of FB.
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