Parathyroid hormone 1 (1–34) acts on the scales and involves calcium metabolism in goldfish

Abstract

The effect of fugu parathyroid hormone 1 (fugu PTH1) on osteoblasts and osteoclasts in teleosts was examined with an assay system using teleost scale and the following markers: alkaline phosphatase (ALP) for osteoblasts and tartrate-resistant acid phosphatase (TRAP) for osteoclasts. Synthetic fugu PTH1 (1-34) (100 pg/ml to 10 ng/ml) significantly increased ALP activity at 6 h of incubation. High-dose (10 ng/ml) fugu PTH1 significantly increased ALP activity even after 18 h of incubation. In the case of TRAP activity, fugu PTH1 did not change at 6 h of incubation, but fugu PTH1 (100 pg/ml to 10 ng/ml) significantly increased TRAP activity at 18 h. Similar results were obtained for human PTH (1-34), but there was an even greater response with fugu PTH1 than with human PTH. In vitro, we demonstrated that both the receptor activator of the NF-B ligand in osteoblasts and the receptor activator NF-B mRNA expression in osteoclasts increased significantly by fugu PTH1 treatment. In an in vivo experiment, fugu PTH1 induced hypercalcemia resulted from the increase of both osteoblastic and osteoclastic activities in the scale as well as the decrease of scale calcium contents after fugu PTH1 injection. In addition, an in vitro experiment with intramuscular autotransplanted scale indicated that the ratio of multinucleated osteoclasts/mononucleated osteoclasts in PTH-treated scales was significantly higher than that in the control scales. Thus, we concluded that PTH acts on osteoblasts and osteoclasts in the scales and regulates calcium metabolism in goldfish.3

Sodium fluoride induces hypercalcemia resulting from the upregulation of both osteoblastic and osteoclastic activities in goldfish, Carassius auratus

“…Previously, we reported that parathyroid hormones first acted on osteoblasts at 6 hours of incubation and then activated osteoclasts at 18 hours of incubation via RANK/RANKL signaling (Suzuki et al, 2011a). Results similar to those of parathyroid hormones were obtained by prostaglandin E2 (Omori et al, 2012).…”

“…These goldfish were kept in the aquarium for 1 and 2 days (each n = 10). These experimental periods were adopted because hormonal and toxicological effects were influenced in goldfish during 2 days (Suzuki et al, 2004a;Suzuki et al, 2004b;Suzuki et al, 2011a;Omori et al, 2012;Yachiguchi et al, 2014b). During the experimental periods, these goldfish were fasted to exclude intestinal calcium uptake from diets.…”

“…The amplification of Elongation factor 1α (EF1α) cDNA using a primer set (Table 1) was performed. The PCR amplification was analyzed by real-time PCR apparatus (Mx3000p, Agilent Technologies, CA, USA) (Suzuki et al 2011a;Thamamongood et al, 2012). The annealing temperature of RANK, RANKL, OPG, TRAF6, NFATc1, CTSK, MMP-9, and EF1α was 60 °C.…”

Effects of Inorganic Mercury and Methylmercury on Osteoclasts and Osteoblasts in the Scales of the Marine Teleost as a Model System of Bone

“…In osteoblasts, also, both InHg and MeHg inhibited the ALP enzyme activity at 18 and 36 hrs after incubation. It is known that the scales are calcified tissue that contains osteoclasts and osteoblasts (Bereiter-Hahn and Zylberberg, 1993;Yoshikubo et al, 2005;Suzuki et al, 2007;Suzuki et al, 2008;de Vrieze et al, 2010;Suzuki et al, 2011a;Thamamongood et al, 2012, Yano et al, 2013. Additionally, it has been reported that scales are a better potential internal calcium reservoir than body skeletons, jaws, and otoliths examined by the 45 Calabeling study of calcified tissues of goldfish and killifish (Mugiya and Watabe, 1977).…”

“…EF-1α (AB874605) was amplified using the following primers: sense: 5′-GTATGGTCGTCACCTTTGCTC-3′; antisense: 5′-GTGGGTCGTTCTTGCTGTC-3′. The PCR amplification was performed using the real-time Mx3000p PCR apparatus (Agilent Technologies, Santa Clara, CA, US) (Suzuki et al, 2011a). The annealing temperature of TRAP, COL1A1, MT, and EF-1α was 60°C.…”