Amomum villosum induces longitudinal bone growth in adolescent female rats

Abstract

Objective: This study was conducted to evaluate the effect of Amomum villosum on longitudinal bone growth.

Methods: Adolescent female Sprague-Dawley rats were divided into 3 groups and treated for 4 days: control (distilled water, p.o.), recombinant human growth hormone (rhGH; 100 microg/kg, s.c.), and A. villosum (500 mg/kg, p.o.) groups. On day 3, tetracycline (20 g/kg, i.p.) was injected for growth plate identification. On days 2, and 4, 5-bromo-2'-deoxyuridine (BrdU) (50 mg/kg, i.p.) was injected to label proliferating cells. On day 5, tibias were dissected and fixed in 4% paraformaldehyde, dehydrated, and sectionedfor immunohistochemistry and histomorphometry.

Results: The rate of bone growth in the A. villosum and rhGH groups increased to (410 +/- 44) and (389 +/- 46) microm/day (P<0.01), respectively, as compared with the control (330.7 +/- 34.7) microm/day. The thickness of the growth plates also increased to (591 +/- 37) and (598 +/- 32) microm, respectively, as compared with the control (524 +/- 89) microm (P<0.001). The number of BrdU-positive cells in the chondrocytes of the A. villosum and rhGH groups was also significantly higher (126 +/- 24) and (143 +/- 18) cells/mm2, respectively) than in the control (109 +/- 25) mm2 (P<0.05). Insulin-like growth factor-1 and bone morphogenetic protein-2 in the A. villosum and rhGH groups were highly expressed in the growth plate as compared with the control samples, indicating increased bone formation.

Conclusions: A. villosum could be used to treat growth retardation during adolescence.