• Journal of Life Science
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• v.30 no.11
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• pp.983-989
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• 2020

The balance between bone-resorbing osteoclasts and bone-forming osteoblasts is key to bone health. An imbalance between osteoclasts and osteoblasts leads to various bone-related disorders, such as osteoporosis, osteomalacia, and osteopetrosis. However, the bone-resorption inhibitor drugs that are currently used may cause side effects. Natural substances have recently received much attention as therapeutic drugs for the treatment of bone health. This study was designed to determine the effect of Tenebrio molitor larvae ethanol extract (TME) on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. To measure the effect of TME on osteoclast differentiation, RAW264.7 cells were treated with RANKL with or without TME for 5 days. The tartrate-resistant acid phosphatase (TRAP) activity was significantly inhibited by treatment of TME without cytotoxicity up to 2 mg/ml. In addition, TME effectively suppressed expression of osteoclast differentiation-related marker genes and proteins such as TRAP, NFATc1, and c-Src. TME also significantly inhibited the p38 mitogen-activated protein kinase (MAPK) signaling pathway without affecting ERK and JNK signaling in RANKL-induced RAW264.7 cells. Consequently, we conclude that TME suppresses osteoclast differentiation by inhibiting RANKL-induced osteoclastogenic genes expression through the p38 MAPK signaling pathways. These results suggest that TME and its bioactive components are potential therapeutics for bone-related diseases such as osteoporosis.

• Journal of Life Science
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• v.26 no.1
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• pp.101-108
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• 2016

The aim of this study was to evaluate the relationships between the expression of Heat shock protein70 (HSP70), Raf-1 and Bcl-2-associated athanogene-1 (BAG1) protein in diffuse type gastric carcinoma and examine association of HSP70, Raf-1 and BAG1 expression with various clinic-pathological factors and survival. Heat shock protein70 is induced in the cells in response to various stress conditions, including carcinogens. Overexpression of heat shock protein 70 has been observed in many types of cancer. The proto-oncoprotein Raf is pivotal for mitogen-activated protein kinase (MAPK) signaling, and its aberrant activation has been implicated in multiple human cancers. Overexpression of BAG1 protein has been documented in some type of human cancer. BAG1 has been reported to interact with protein involved with a variety of signal pathway, and regulation of cell differentiation, survival and apoptosis. These interaction partners include HSP70 and Raf-1. The percentage of tumors exhibiting HSP70 positivity was significantly in cases of positive lymph node metastasis (64.9%) compared to cases without lymph node metastasis (35.1%, p=0.007). HS70 expression was correlated with pathological N-stage (p=0.006). Expression of BAG1 was detected in the majority of diffuse type gastric carcinoma tissues (71.7%), especially in younger patients (80% vs 52.6%, p=0.035). Furthermore BAG1 expression was correlated with tumor size (p=0.020). Raf-1 expression was found to be significantly associated with tumor size (p=0.005). The result indicate that HSP70 was significantly correlated the progression of diffuse type gastric cancer. Expression of BAG1 and Raf-1 may be used as diagnostic markers for gastric carcinoma.