title: Characterization of sarcoplasmic reticulum Ca(2+) ATPase pumps in muscle of patients with myotonic dystrophy and with hypothyroid myopathy.
abstract: Sarcoplasmic/endoplasmic reticulum Ca(2+) ATPase (SERCA) pumps play the major role in lowering cytoplasmic calcium concentration in skeletal muscle by catalyzing the ATP-dependent transport of Ca(2+) from the cytosol to the lumen of the sarcoplasmic reticulum (SR). Although SERCA abnormalities have been hypothesized to contribute to the dysregulation of intracellular Ca(2+) homeostasis and signaling in muscle of patients with myotonic dystrophy (DM) and hypothyroid myopathy, the characterization of SERCA pumps remains elusive and their impairment is still unclear. We assessed the activity of SR Ca(2+)-ATPase, expression levels and fiber distribution of SERCA1 and SERCA2, and oligomerization of SERCA1 protein in muscle of patients with DM type 1 and 2, and with hypothyroid myopathy. Our data provide evidence that SR Ca(2+) ATPase activity, protein levels and muscle fiber distribution of total SERCA1 and SERCA2, and SERCA1 oligomerization pattern are similar in patients with both DM1 and DM2, hypothyroid myopathy and in control subjects. We prove that SERCA1b, the neonatal isoform of SERCA1, is expressed at protein level in muscle of patients with DM2 and, in lower amount, of patients with DM1. Our present study demonstrates that SERCA function is not altered in muscle of patients with DM and with hypothyroid myopathy.
authors.affiliation: Department of Neurological and Movement Sciences, Section of Clinical Neurology, University of Verona, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Guglielmi
authors.affiliation: Department of Biochemistry, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Oosterhof
authors.affiliation: Neuromuscular Centre Nijmegen, Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: N C
authors.initials: NC
authors.lastname: Voermans
authors.affiliation: Department of Biomedical Sciences for Health, IRCCS Policlinico San Donato, University of Milan, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Cardani
authors.affiliation: Neuromuscular Centre Nijmegen, Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: J P
authors.initials: JP
authors.lastname: Molenaar
authors.affiliation: Department of Biochemistry, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: T H
authors.initials: TH
authors.lastname: van Kuppevelt
authors.affiliation: Department of Biomedical Sciences for Health, IRCCS Policlinico San Donato, University of Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Meola
authors.affiliation: Neuromuscular Centre Nijmegen, Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: B G
authors.initials: BG
authors.lastname: van Engelen
authors.affiliation: Department of Neurological and Movement Sciences, Section of Clinical Neurology, University of Verona, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Tomelleri
authors.affiliation: Department of Neurological and Movement Sciences, Section of Clinical Neurology, University of Verona, Italy. Electronic address: gaetano.vattemi@univr.it.
authors.forename: G
authors.initials: G
authors.lastname: Vattemi
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000201:enzymology* / Q000473:pathology; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000473:pathology; D009223:Myotonic Dystrophy / Q000201:enzymology* / Q000473:pathology; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000378:metabolism*; D055815:Young Adult
chemical_list: D007527:Isoenzymes; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; C506943:ATP2A1 protein, human; C506946:ATP2A2 protein, human
keywords: Brody myopathy; Hypothyroid myopathy; Myotonic dystrophy; SERCA1b; Sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase 1 (SERCA1)