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Calmodulin antagonists increase the amount of mRNA for the low-density-lipoprotein receptor in skin fibroblasts.

ABSTRACT: The effects of calmodulin antagonists on the amount of LDL receptor (LDL-R) mRNA in cultured human fibroblasts was examined by hybridization with a fragment of LDL-R cDNA. In a 'Northern' blot the fragment hybridized to a 5.3-kilobase RNA, as expected for LDL-R mRNA. The concentration of this RNA was increased in preparations from cells that were treated with trifluoperazine or W-7 [N-(6-aminohexyl)-5-chloronaphthalene-1-sulphonamide]. The selectivity of the increase was established by using a probe for beta-actin mRNA. In dot-blot hybridization it was observed that the calmodulin antagonists cause 2-4-fold relative increase in the amount of LDL-R mRNA.

SUBMITTER: Eckardt H

PROVIDER: S-EPMC1149230 | biostudies-other | 1988 Jun

REPOSITORIES: biostudies-other

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Agents which increase cyclic AMP have diverse effects on low-density-lipoprotein-receptor function in human vascular smooth-muscle cells and skin fibroblasts.

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| S-EPMC6156287 | biostudies-literature

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Farnesoid X Receptor Activation by Obeticholic Acid Elevates Liver Low-Density Lipoprotein Receptor Expression by mRNA Stabilization and Reduces Plasma Low-Density Lipoprotein Cholesterol in Mice.

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Rapid Increase in Serum Low-Density Lipoprotein Cholesterol Concentration during Hepatitis C Interferon-Free Treatment.

Project description:Background & aimWe performed lipid analyses at the early period of therapy in patients with chronic hepatitis C who underwent interferon (IFN)-free direct-acting antiviral (DAA) treatment, and we attempted to identify the factors that contributed to a rapid increase in the patients' serum low-density lipoprotein cholesterol (LDL-C) concentration.MethodsWe retrospectively analyzed the cases of 100 consecutive patients with HCV infection treated at the National Hospital Organization Nagasaki Medical Center: 24 patients underwent daclatasvir (DCV) and asunaprevir (ASV) combination therapy (DCV/ASV) for 24 weeks, and the other 76 patients underwent ledipasvir and sofosbuvir combination therapy (LDV/SOF) for 12 weeks. ?LDL-C was defined as the changed in LDL-C level at 28 days from the start of therapy. To determine whether ?LDL-C was associated with several kinds of factors including viral kinetics, we performed a stepwise multiple linear regression analysis.ResultsThe LDL-C levels in patients treated with LDV/SOF were markedly and significantly elevated (87.45 to 122.5 mg/dl; p<10-10) compared to those in the DCV/ASV-treated patients (80.15 to 87.8 mg/dl; p = 0.0056). The median levels of ?LDL-C in the LDV/SOF and DCV/ASV groups were 33.2 and 13.1, respectively. LDV/SOF combination therapy as an IFN-free regimen (p<0.001) and ?HCV core antigen (0-1 day drop) (p<0.044) were identified as independent factors that were closely related to the ?LDL-C.ConclusionsA rapid increase in the serum LDL-C concentration during the IFN-free treatment of hepatitis C was associated with the type of HCV therapy and a decline of HCV core protein.

| S-EPMC5040437 | biostudies-literature

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