We evaluated whether changes in protein content and activity of PP-1 and PP-2A were the mechanism underneath the basal age-related reduction in alpha(2/3)-Na,K-ATPase activity in rats cerebella and whether this occurred through the cyclic GMP-PKG pathway. PP1 activity, but not its expression, increased with age, whereas PP-2 was not changed. The activity of alpha(2/3)-Na,K-ATPase varied with age, and there was a negative association between the PP-1 and alpha(2/3)-Na,K-ATPase activities. In young rats, the inhibition of PP-1 and PP-2A by okadaic acid (OA) increased in a dose-dependent manner alpha(1)- and alpha(2/3)-Na,K-ATPase, but had no effect on Mg-ATPase activity. A direct stimulation of PKG with 8-Br-cyclic GMP did not surmount the effect of OA. This analogue of cyclic GMP inhibited PP-1 activity only, indicating that at least part of the increase in alpha(1)- and alpha(2/3)-Na,K-ATPase activity induced by OA was mediated by the cyclic GMP-PKG-PP-1 cascade. Taking into account that PP1 inhibition increased alpha(2/3)-Na,K-ATPase activity, we propose that an age-related increase in PP-1 activity due to a decrease in cyclic GMP-PKG modulation plays a role for the age-related reduction of alpha(2/3)-Na,K-ATPase activity in rat cerebellum.
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http://dx.doi.org/10.1016/j.neurobiolaging.2007.04.008 | DOI Listing |
Chem Biol Interact
January 2025
Department of Biotechnology, Daegu University, Gyeongsan, Gyeongbuk 38453, Republic of Korea. Electronic address:
Capsaicin, a polyphenol, is known to regulate energy expenditure and thermogenesis in adipocytes and muscles. However, its role in modulating uncoupling proteins (UCPs) and adenosine triphosphate (ATP)-dependent thermogenesis in muscles remains unclear. This study investigated the mechanisms underlying the role of capsaicin in modulating the UCP- and ATP-dependent thermogenesis in C2C12 myoblasts, as well as the gastrocnemius (GM) and soleus muscles (SM) of mice.
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Lab. Genetics and Molecular Bases of Complex Diseases, Health Research Institute of Hospital Clínico San Carlos (IdISSC), 28040, Madrid, Spain.
The underlying mechanisms explaining the differential course of SARS-CoV-2 infection and the potential clinical consequences after COVID-19 resolution have not been fully elucidated. As a dysregulated mitochondrial activity could impair the immune response, we explored long-lasting changes in mitochondrial functionality, circulating cytokine levels, and metabolomic profiles of infected individuals after symptoms resolution, to evaluate whether a complete recovery could be achieved. Results of this pilot study evidenced that different parameters of aerobic respiration in lymphocytes of individuals recuperated from a severe course lagged behind those shown upon mild COVID-19 recovery, in basal conditions and after simulated reinfection, and they also showed altered glycolytic capacity.
View Article and Find Full Text PDFJ Virol
January 2025
Department of Host-Microbe Interactions, St Jude Children's Research Hospital, Memphis, Tennessee, USA.
Unlabelled: The tonsils have been identified as a site of replication for Epstein-Barr virus, adenovirus, human papillomavirus, and other respiratory viruses. Human tonsil epithelial cells (HTECs) are a heterogeneous group of actively differentiating cells. Here, we investigated the cellular features and susceptibility of differentiated HTECs to specific influenza viruses, including expression of avian-type and mammalian-type sialic acid (SA) receptors, viral replication dynamics, and the associated cytokine secretion profiles.
View Article and Find Full Text PDFJCEM Case Rep
January 2025
Division of Diabetology and Metabolism, Department of Internal Medicine, Tokyo Women's Medical University School of Medicine, Shinjuku-ku, Tokyo 162-8666, Japan.
A 37-year-old man presented with symptoms of polyuria and weight loss over the past year. Initial laboratory examination showed elevated blood glucose level (468 mg/dL [25.9 mmol/L]; normal reference range [RR], 75-109 mg/dL [4.
View Article and Find Full Text PDFArch Physiol Biochem
January 2025
Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway.
Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) plays a crucial role in regulation of metabolic homeostasis. To understand the role of the catalytic α2 subunit of AMPK in skeletal muscle energy metabolism, myotube cultures were established from and mice. Myotubes from mice had lower basal oleic acid and glucose oxidation compared to myotubes from mice.
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