Functional Effects of Sericin on Bone Health and D-Serine Regulation in Estrogen-Deficient Rats
Source abstract
Abstract
Postmenopausal osteoporosis is characterized by progressive bone loss and deterioration of trabecular microarchitecture, yet safe and effective nutritional interventions remain limited. This study investigated the skeletal effects of whole sericin compared to isolated L-serine and calcium-only formulations in an ovariectomized (OVX) rat model. Forty female Sprague–Dawley rats underwent either sham surgery or OVX, followed by 8 weeks of daily oral administration with vehicle (calcium + vitamin D, NS), sericin formulation (S55), or L-serine. Sham and untreated OVX groups served as controls. Serum D-serine concentrations and femoral trabecular microarchitecture were assessed using fluorometric assays and micro-computed tomography (μCT), respectively. OVX significantly decreased bone volume fraction (BV/TV), bone mineral density (BMD), and trabecular number, while increasing trabecular separation. Sericin supplementation markedly improved BV/TV, BMD, trabecular thickness, and trabecular number, and reduced trabecular separation compared to both vehicle and untreated OVX controls. Sericin improved multiple trabecular parameters compared with L-serine. Serum D-serine levels were significantly elevated in the sericin group relative to calcium-only controls, though comparable to sham. These findings suggest that whole sericin exerts skeletal benefits beyond those attributable to its primary amino acid component, supporting its potential as a functional food ingredient for enhancing postmenopausal bone health.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Amino Acid Enzymes and Metabolism · Biochemical effects in animals · Food Quality and Safety Studies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Oral and Maxillofacial Surgery, College of Dentistry, Gangneung-Wonju National University, Gangneung-si 25457, Republic of Korea
Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, School of Medicine, Kyungpook National University, Daegu 41944, Republic of Korea
Department of Oral Pathology, College of Dentistry, Gangneung-Wonju National University, Gangneung-si 25457, Republic of Korea
Industrial Entomology Division, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea
Funding
Rural Development Administration
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