Abstract
The objective of this study was to investigate the effects of low-protein diets on blood calcium (Ca) level, bone metabolism, and the correlation between bone metabolism and blood calcium in goats. Twenty-four female Xiangdong black goats with similar body weight (19.55 ± 3.55 kg) and age (8.0 ± 0.3 months) were selected and allocated into two groups: control group (CON, 10.77% protein content) and low-protein group (LP, 5.52% protein content). Blood samples were collected on days 1, 4, 7, 16 and 36 before morning feeding to determine the concentration of calcium (Ca), parathyroid hormone (PTH), bone gla protein (BGP), C-terminal telopeptide of type 1 collagen (CTX-1), bone alkaline phosphatase (BALP), and 1, 25-dihydroxyvitamin D3 [1,25(OH)2D3]. Liver samples were collected to determine the expression of bone metabolism-related genes. There was no difference observed between LP and CON in concentration of plasma Ca or any of bone metabolism markers (P > 0.05). In the liver, the mRNA expression of bone gamma carboxyglutamate protein (BGLAP), alkaline phosphatase (ALPL), and mothers against decapentaplegic homolog-1 (SMAD1) were increased (P < 0.05) in LP as compared with CON. The correlation analysis of Ca and bone metabolism markers showed no significant correlation between Ca and bone metabolism. These results suggest that the blood Ca concentration in mature goats may keep at a stable level through nitrogen cycling when the providing protein is not enough.
Highlights
Calcium (Ca) is an essential mineral in the physical and is closely related to various physiological and pathological processes [1]
The lipoprotein receptor related protein 6 (LRP6) (P = 0.05), matrix metalloproteinase 16 (MMP16) (P = 0.07), and bone morphogenetic protein 2 (BMP2) (P = 0.06) mRNA expression in LP tended to be increased when compared with CON
It is possible that the goats with insufficient dietary protein may maintain the balance of bone metabolism through the BMP-Smad Runx2 axis and the Wingless tail (Wnt) signaling pathway
Summary
Calcium (Ca) is an essential mineral in the physical and is closely related to various physiological and pathological processes [1]. It has been reported that bone metabolism is closely linked to Ca homeostasis, including bone resorption and bone formation, of which bone resorption is necessary to maintain an appropriate level of blood Ca [2]. Bone resorption dissolves the mineralized matrix of bone under the control of osteoclasts and hormones such as parathyroid hormone (PTH) and 1, 25dihydroxyvitamin D3 (1,25(OH) D3), releasing ionized Ca into the blood and altering the blood Ca concentration [11, 12]. As most Ca is located in bone [13], and the plasma calcium concentration is tightly controlled in a narrow range to maintain numerous fundamental physiological functions of the body [14]. It has been reported that the total plasma calcium ranges from 2.0 to 3.0 mmol/L [15], and Ca deficiency can lead to delayed growth and development and pathological risks such as osteoporosis, rickets, and osteochondrosis [16]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
