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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of Life Science
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Korean Society of Life Science
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Volume & Issues
Volume 25, Issue 12 - Dec 2015
Volume 25, Issue 11 - Nov 2015
Volume 25, Issue 10 - Oct 2015
Volume 25, Issue 9 - Sep 2015
Volume 25, Issue 8 - Aug 2015
Volume 25, Issue 7 - Jul 2015
Volume 25, Issue 6 - Jun 2015
Volume 25, Issue 5 - May 2015
Volume 25, Issue 4 - Apr 2015
Volume 25, Issue 3 - Mar 2015
Volume 25, Issue 2 - Feb 2015
Volume 25, Issue 1 - Jan 2015
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Calpain Protease-dependent Post-translational Regulation of Cyclin D3
Hwang, Won Deok ; Choi, Yung Hyun ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 1~7
DOI : 10.5352/JLS.2015.25.1.1
Cyclin D is a member of the cyclin protein family, which plays a critical role as a core member of the mammalian cell cycle machinery. D-type cyclins (D1, D2, and D3) bind to and activate the cyclin-dependent kinases 4 and 6, which can then phosphorylate the retinoblastoma tumor suppressor gene products. This phosphorylation in turn leads to release or derepression of E2F transcription factors that promote progression from the G1 to S phase of the cell cycle. Among the D-type cyclins, cyclin D3 encoded by the CCND3 gene is one of the least well studied. In the present study, we have investigated the biochemistry of the proteolytic mechanism that leads to loss of cyclin D3 protein. Treatment of human prostate carcinoma PC-3-M cells with lovastatin and actinomycin D resulted in a loss of cyclin D3 protein that was completely reversible by the peptide aldehyde calpain inhibitor, LLnL. Additionally, using inhibitors for various proteolytic systems, we show that degradation of cyclin D3 protein involves the
-activated neutral protease calpain. Moreover, the half-life of cyclin D3 protein half-life increased by at least 10-fold in PC-3M cells in response to the calpain inhibitor. We have also demonstrated that the transient expression of the calpain inhibitor calpastatin increased cyclin D3 protein in serum-starved NIH 3T3 cells. These data suggested that the function of cyclin D3 is regulated by
-dependent protease calpain.
Association of Insulin-related Genes Expression with Carcass Weight in Loin Muscle of Korean Cattle (Hanwoo)
Lim, Dajeong ; Cho, Yong-Min ; Chai, Han-Ha ; Lee, Seung-Hwan ; Choi, Bong-Hwan ; Kim, Nam-Kuk ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 8~15
DOI : 10.5352/JLS.2015.25.1.8
The peroxisome proliferator-activated receptor (PPAR) signaling pathway is well known as a candidate pathway related to meat quality in mammals. In particular, there are many studies on the relationship between the PPAR signaling pathway and intramuscular fat. However, recent studies have demonstrated that genes in the PPAR signaling pathway are associated with carcass weight in cattle. Among 48 genes in the PPAR signaling pathway, 16 genes are related to the insulin that regulates the adipocyte glucose metabolism and thus affects body weight. Therefore, we conducted an investigation to try to identify candidate genes associated with the carcass weight and relationships between the expressions of these 16 genes in the loin muscle of Hanwoo (Korean cattle). From regression analysis, the three genes (ACSL6, FADS2, and ILK) showed significant effects with regard to carcass weight (p<0.05). Finally, we analyzed the common regulators of the significant genes from pathway analysis. The significant genes are regulated by insulin as well as D-glucose. These findings show that the differentially expressed genes are possible candidate genes associated with carcass weight in the longissimus muscle of Korean cattle.
Possibility of Natural Hybridization between Red Seabream (Pagrus major) and Blackhead Seabream (Acanthopagrus schlegeli)
Kang, Jung-Ha ; Yang, Sang-Geun ; Kim, Eun-Mi ; Noh, Eun-Soo ; Kim, Dong-Gyun ; Kim, Bong-Seok ; Choi, Tae-Jin ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 16~20
DOI : 10.5352/JLS.2015.25.1.16
During the storage of these two species in a large conservation tank, fertilized eggs were collected and the offspring were raised. During culturing of the offspring, individuals with mixed characteristics of these two species were observed, and 96 individuals were randomly tested using microsatellite markers applicable to both species. Among the 96 individuals, 15 individuals with mixed morphological characteristics were confirmed to be hybrids showing both of genotypes red seabream and blackhead seabream. Additionally, based on sequence analysis of mitochondrial cytochrome oxidase subunit 1 (mtDNA CO1), 81 showed 99% nucleotide sequence identity to that of black sea bream, and the remaining 15 individuals showed over 99% sequence identity to that of red seabream. So, hybrids were produced by female red seabream and male blackhead seabream. These results suggest that hybrids may form in nature between these two species if their habitats overlap due to the influence of humans or global climate change.
Effects of Genetic Polymorphisms of ADD1 Gene on Economic Traits in Hanwoo and Jeju Black Cattle-derived Commercial Populations in Jeju-do
Han, Sang-Hyun ; Oh, Hong-Shik ; Lee, Jae-Bong ; Jwa, Eun-Sook ; Kang, Yong-Jun ; Kim, Sang-Geum ; Yang, Sung-Nyun ; Kim, Yoo-Kyung ; Cho, In-Cheol ; Cho, Won-Mo ; Ko, Moon-Suck ; Baek, Kwang-Soo ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 21~28
DOI : 10.5352/JLS.2015.25.1.21
Genetic polymorphisms of adipocyte determination and differentiation factor 1 (ADD1) gene were screened in Hanwoo and Jeju Black cattle-derived commercial (JBC-DC) populations. The ADD1 genotypes were determined using the presence/absence of 84-bp fragment at intron 7 region. The association of ADD1 genotypes for economic traits was examined in both populations. In the Hanwoo steers, ADD1 D/- carcasses showed significantly thicker backfat levels than those from WW (p<0.05). However, the thickest level of backfat appeared in WD heterozygotes, whereas thicker backfat did not appear in DD homozygotes in the JBC-DC population (p<0.05), leading to the supposition that synergic effects of alleles W and D increase backfat deposition. On the other hand, there was no association between the ADD1 genotypes and intramuscular fat deposition measured as meat quality index and marbling score. From these results, we concluded that the bovine ADD1 affected the backfat in subcutaneous tissue, rather than intramuscular fat in muscle tissue. In addition, the DD animals showed higher levels of meat color than those from W/- (p<0.05). Interestingly, a highly significant difference was found between the genotypes and carcass weights only in the JBC-DC population, and D/- animals were heavier by more than 38 kg than those from WW (p<0.001). The results of this study reveal faster growth rate and differences in steer productivity according to genotypes of the ADD1 gene. These findings demonstrate that ADD1 genotypes may effectively function as molecular genetic markers for the improvement of Hanwoo and Jeju Black cattle-related crossbreeding systems.
Anti-MRSA Properties of Prodigiosin from Serratia sp. PDGS 120915
Ji, Keunho ; Jeong, Tae Hyug ; Kim, Young Tae ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 29~36
DOI : 10.5352/JLS.2015.25.1.29
Prodigiosin, a member of natural red pigment family, is produced by Serratia marcescens, and characterized by a common pyrrolylpyrromethane skeleton. This pigment has been reported with the effects of anticancer, immunosuppressant, antifungal, and algicidal activities. Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of hospital infections. In this study, anti-MRSA properties of prodigiosin isolated from Serratia sp. PDGS 120915 were investigated. We identified and purified prodigiosin using high performance liquid chromatography (HPLC) and evaluated anti-MRSA activity. Purified prodigiosin inhibited the growth of MRSA. The minimum inhibitory concentrations (MICs) of prodigiosin were determined to
against the MRSA strains. Fractional inhibitory concentration (FIC) indices of ampicillin and penicillin were indicated synergistic effects of prodigiosin on MRSA.
Effects of Ethylene Precursor, Auxin and Methyl Jasmonate on the Aerenchyma Formation in the Primary Root of Maize (Zea mays)
Ho, Jongyoon ; Maeng, Sohyun ; Park, Woong June ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 37~43
DOI : 10.5352/JLS.2015.25.1.37
We have investigated the effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) and methyl jasmonate (MeJA) on the development of aerenchyma in the primary root of maize (Zea mays). Because plant hormones affected the longitudinal organization of the primary root, we need an indicator to direct the positions for comparison between control and hormone-treated roots. Therefore, the zones of the maize primary root were categorized as PR25, PR50 and PR75, where each value indicates the relative position between the root tip (PR0) and the base (PR100). Aerenchyma was not observed at PR25 and PR50 and rarely found at PR75 in the cortex of control roots. The aerenchymal area at PR75 increased in the presence of the ethylene precursor ACC or a natural auxin IAA. On the other hand, MeJA differentially acted on non-submerged and submerged roots. Exogenously applied MeJA suppressed the aerenchyma formation in non-submerged roots. When the primary root was submerged, aerenchymal area expanded prominently. The submergence-induced aerenchyma formation was amplified with MeJA. Lateral root primordia have been known to inhibit aerenchymal death of surrounding cells. All the three hormones stimulating aerenchyma formation as described above did not restore the inhibition caused by lateral root primordia, suggesting that the inhibitory step regulated by lateral root primordia can be located after hormonal signaling steps.
Anti-oxidant, Anti-inflammatory and Anti-cancer Effect of Methanol Extract of Pogostemon cablin
Yun, Seung Geun ; Jin, Soojung ; Jeong, Hyun Young ; Yun, Hee Jung ; Do, Mi young ; Kim, Byung Woo ; Kwon, Hyun Ju ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 44~52
DOI : 10.5352/JLS.2015.25.1.44
In the present study, the substance that show anti-proliferation of cancer cells as well as anti-oxidant and anti-inflammatory effect was searched. As a results, the methanol extract of Pogostemon cablin (P. cablin), is a well-known herb for traditional medicine in Korea and China for treating the digestive disorders, less of appetite, vomiting and diarrhea, inhibited the growth of various cancer cells such as A549, HepG2, MCF7 and HT29 cells. Cytotoxic effect of methanol extraction of P. cablin was excellent in A549 cells. P. cablin extract induced cell cycle arrest at G1 phase of A549 in a dose dependent manner. And it induced phosphorylation of p38 and Cdc25A and reduced expression of Cdc25A, Cdks, Cyclins and phospho-Retinoblastoma (Rb) proteins. Therefore, P. cablin extract seems to act through the p38 - Cdc25A - Cdk - Cyclin - Rb pathway in A549 cells. In addition, P. cablin extract showed anti-oxidant effect by DPPH free radical scavenging assay and anti-inflammation effect by inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) in RAW 264.7 cells in a dose-dependent manner. Taken together, these results suggest that P. cablin may be used as not only candidate materials for anti-cancer, anti-inflammatory and anti-oxidant, moreover, it would be possible utilized in various health functional food materials.
Isolation and Structure Identification of Photosensitizer from Perilla frutescens Leaves Which Induces Apoptosis in U937
Ha, Jun Young ; Kim, Mi Kyeong ; Lee, Jun Young ; Choi, Eun Bi ; Hong, Chang Oh ; Lee, Byong Won ; Bae, Chang Hwan ; Kim, Keun Ki ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 53~61
DOI : 10.5352/JLS.2015.25.1.53
In this study, we tried to separate the photosensitizer that induces apoptosis of leukemia cells (U937) from perilla leaves. Perilla leaves (Perilla frutescens Britt var. japonica Hara) are a popular vegetable in Korea, being rich in vitamins (A and E), GABA, and minerals. Dried perilla leaves were extracted with methanol to separate the photosensitizer by various chromatographic techniques. The structure of the isolated compound (PL9443) was identified by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. Absorbance of the UV-Vis spectrum was highest at 410 nm and was confirmed by the 330, 410, and 668 nm. PL9443 compound was determined to be pheophorbide, an ethyl ester having a molecular weight of 620. It was identified as a derivative compound of pheophorbide structure when magnesium comes away from a porphyrin ring. Observation of morphological changes in U937 cells following cell death induced by treated PL9443 compound revealed representative phenomena of apoptosis only in light irradiation conditions (apoptotic body, vesicle formation). Results from examining the cytotoxicity of PL9443 substance against U937 cells showed that inhibition rates of the cell growth were 99.9% with the concentration of 0.32 nM PL9443. Also, the caspase-3/7 activity was 99% against U937 cells with the concentration of 0.08 nM of PL9443 substance. The result of the electrophoresis was that a DNA ladder was formed by the PL9443. The PL9443 compound is a promising lead compound as a photosensitizer for photodynamic therapy of cancer.
Effects of Myelophycus Simplex Papenfuss Methanol Extract on Adipocyte Differentiation and Adipogenesis in 3T3-L1 Preadipocytes
Kim, Hyang Suk ; Kwon, Da Hye ; Cheon, Ji Min ; Choi, Eun Ok ; Kim, Ji Hyun ; Han, Min Ho ; Choi, Yung Hyun ; Kim, Byung Woo ; Hwang, Hye Jin ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 62~67
DOI : 10.5352/JLS.2015.25.1.62
Myelophycus simplex Papenfuss is distributed over the northern Pacific and southern coast of Korea, and is a member of the brown algae family. The objective of this study was to investigate the effect of M. simplex methanol extract on adipocyte differentiation and adipogenesis in 3T3-L1 preadipocytes. Treatment with M. simplex methanol extract significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by a decrease in lipid droplet content observed by Oil Red O staining. Also, the M. simplex methanol extract significantly suppressed the triglyceride content of 3T3-L1 preadipocytes in a dose-dependent manner. Treatment with 300 and
of M. simplex methanol extract caused a 42% and 76% reduction in lipid droplet content, respectively. In order to understand the anti-adipogenic effects of M. simplex methanol extract, the changes in the expression of several adipogenic transcription factors, including peroxisome proliferator-activated receptor (PPAR)
-cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding protein (C/EBP)
, were investigated using immunoblotting. M. simplex suppressed the expression of
proteins compared with control. Therefore, the results of this study suggest that M. simplex methanol extract inhibits adipocyte differentiation and thus may have applications as a potential source for an anti-obesity functional food agent.
Characteristics of Pop-rice and Rice Tea Using Black Sticky Rice with Giant Embryo
Han, Sang-Ik ; Seo, Woo Duck ; Na, Ji-Eun ; Park, Ji-Young ; Park, Dong-Soo ; Cho, Jun-Hyun ; Lee, Jong-Hee ; Seo, Kyung-Hye ; Sim, Eun-Yeong ; Nam, Min-Hee ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 68~74
DOI : 10.5352/JLS.2015.25.1.68
Recently developed black waxy rice with a giant embryo (`Nunkeunheukchal`, BGE) was selected and processed to produce high quality nutritional food. BGE contains high levels of several phytochemicals with antioxidant activities, as well as other reported health beneficial properties. In addition, the giant embryo has high protein, lipid, and amino acids contents. Within the free amino acids,
-aminobutyric acid (GABA), a major inhibitory neurotransmitter, has long been used for treating the aftereffects of brain injuries and stroke. A method for manufacturing pop-rice and black rice tea by popping process in BGE is provided to increase a taste, nutrition and functionality. The produced `pop-rice` showed increased protein (11.3%) and lipid (3.7%) contents compared with control variety, IB (`Ilmibyeo`). In addition, melanoidin related products, polyphenol and functional amino acid contents were increased by the popping process. Pop-rice tea made of BGE showed the highest extraction of total sugar, glucose, raffinose and sucrose (4 times higher than brown rice) by hot water. Scavenging activity (
) of processed BGE rice powder showed strong antioxidative activity of 0.24 mg/ml using DPPH and 1.82 mg/ml using ABTs method. Thereafter, these results suggested that the popping processed rice of BGE could be one of the promising materials for healthy food development.
Fermentation Properties and Inflammatory Cytokines Modulating of Fermented Milk with Curcuma longa L Powder
Gereltuya, Renchinkhand ; Son, Ji Yoon ; Magsar, Urgamal ; Paik, Seung-Hee ; Lee, Jo Yoon ; Nam, Myoung Soo ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 75~83
DOI : 10.5352/JLS.2015.25.1.75
Curcuma longa L. (CL), a traditional medicinal plant, is well known as a functional food ingredient. The major component of CL is a curcumin of anthocyanin family that has multi-functions such as antimicrobial, anticancer, and antioxidant activity. In this study, fermented milk containing CL was prepared using a mixed strain culture (Bifidobacterium bifidus, Streptococcus thermophilus, Lactobacillus acidophilus), and its physicochemical properties were characterized. In addition, inflammatory cytokine-modulating effects of the fermented milk were also investigated. As regards the properties of fermented milk, the growth rate of lactic acid bacteria in fermented milk containing CL was found to be remarkably more rapid than control. During fermentation, caseins and whey proteins were observed to be partially hydrolyzed, and lactic acid and acetic acid were produced in larger amounts than in the control. The sensory score of fermented milk containing CL was lower than control, owing to its bitter taste and strong flavor. RAW 264.7 cells treated with CL fermented milk supernatant showed no cytotoxicity. Inflammatory cytokines such as tumor necrosis factor-alpha (TNF-
) and interleukin-6 (IL-6) were significantly produced by fermented milk with CL, compared to control. The secretion of nitric oxide (NO) from RAW 264.7 cells significantly increased relative to the control. Results from the present study suggested that CL could be used as a natural immunomodulating ingredient for making yogurts, beverages, and other products.
Identification of the Polymorphisms in IFITM2 and IFITM5 Genes and their Association with Ulcerative Colitis
Kim, Hun-Soo ; Mo, Ji-Su ; Alam, Khondoker Jahengir ; Park, Won-Cheol ; Kim, Keun Young ; Chae, Soo-Cheon ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 84~92
DOI : 10.5352/JLS.2015.25.1.84
Interferon inducible transmembrane protein (IFITM) family genes have been implicated in various cellular processes such as the homotypic cell adhesion functions of IFNs and cellular anti-proliferative activities. The present study aimed to investigate whether the polymorphisms of the IFITM2 and IFITM5 genes are associated with susceptibility to UC. We identified a total of thirteen polymorphisms (eleven SNPs and two variations) in the IFITM2 gene and twelve polymorphisms (eleven SNPs and one variation) in the IFITM5 gene, by the direct sequencing method. Genotype analysis in the IFITM2 and IFITM5 SNPs was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and Taq-Man probe analysis, and the haplotype frequencies of IFITM2 and IFITM5 SNPs for multiple loci were estimated using the expectation maximization (EM) algorithm. The genotype and allele frequencies of IFITM2 SNPs, as well as IFITM5 SNPs, in UC patients were not significantly different from those of the healthy controls. We also analyzed the combined frequencies of rs77537847 of IFITM1, rs909097 of IFITM2, and rs56069858 of IFITM5 in the UC patients and the healthy controls. Although the distribution of the major combined genotype frequency did not differ significantly between the healthy controls and the UC patients, the GGT combined frequency in the healthy controls was significantly different from that in the UC patients (P
Induction of Apoptosis by Pachymic Acid in T24 Human Bladder Cancer Cells
Jeong, Jin-Woo ; Baek, Jun Young ; Kim, Kwang Dong ; Choi, Yung Hyun ; Lee, Jae-Dong ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 93~100
DOI : 10.5352/JLS.2015.25.1.93
Pachymic acid (PA) is a lanostane-type triterpenoid derived from the Poria cocos mushroom. Several beneficial biological features of PA provide medicine with a wide variety of valuable effects, such as anticancer and anti-inflammatory activity; it also has antioxidant effects against oxidative stress. Nonetheless, the biological properties and mechanisms that produce this anti-cancer action of PA remain largely undetermined. In this study, we investigated the pro-apoptotic effects of PA in T24 human bladder cancer cells. It was found that PA could inhibit the cell growth of T24 cells in a dose-dependent manner, which was associated with the induction of apoptotic cell death, as evidenced by the formation of apoptotic bodies and chromatin condensation and accumulation of cells in the sub-G1 phase. The induction of apoptotic cell death by PA was connected with an up-regulation of pro-apoptotic Bax and Bad protein expression and down-regulation of anti-apoptotic Bcl-2 and Bcl-xL proteins, and inhibition of apoptosis family proteins. In addition, apoptosis-inducing concentrations of PA induced the activation of caspase-9, an initiator caspase of the mitochondrial-mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of poly (ADP-ribose)-polymerase. PA also induced apoptosis via a death receptor-mediated extrinsic pathway by caspase-8 activation, resulting in the truncation of Bid and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. Taken together, the present results suggest that PA may be a potential chemotherapeutic agent for the control of human bladder cancer cells.
PDZ Domain-containing Proteins at Autotypic Junctions in Myelinating Schwann Cells
Han, Seongjohn ; Park, Hyeongbin ; Hong, Soomin ; Lee, Donghyun ; Choi, Maro ; Cho, Jeongmok ; Urm, Sang-Hwa ; Jang, Won Hee ; Seog, Dae-Hyun ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 101~112
DOI : 10.5352/JLS.2015.25.1.101
A type of cell junction that is formed between different parts within the same cell is called autotypic cell junction. Autotypic junction proteins form tight junctions found between membrane lamellae of a cell, especially in myelinating glial cells. Some of them have postsynaptic density-95/disks large/zonula occludens-1 (PDZ) domains, which interact with the carboxyl (C)-terminal PDZ-binding motif of other proteins. PDZ domains are protein-protein interaction modules that play a role in protein complex assembly. The PDZ domain, which is widespread in bacteria, plants, yeast, metazoans, and Drosophila, allows the assembly of large multi-protein complexes. The multi-protein complexes act in intracellular signal transduction, protein targeting, and membrane polarization. The identified PDZ domain-containing proteins located at autotypic junctions include zonula occludens-1 (ZO-1), ZO-2, pals-1-associated tight junction protein (PATJ), multi-PDZ domain proteins (MUPPs), membrane-associated guanylate kinase inverted 2 (MAGI2), and protease-activated receptor (PAR)-3. PAR-3 interacts with atypical protein kinase C and PAR-6, forming a ternary complex, which plays an important role in the regulation of cell polarity. MAGI2 interacts with
-amino-3-hydroxyl-5-methyl-4-isoxazole propionate (AMPA) receptor at excitatory synapses. PATJ is detected in paranodal loops associated with claudin-1. On the other hand, MUPP1 is found in mesaxons and Schmidt-Lanterman incisures with claudin-5. ZO-1, ZO-2, and PAR-3 are found at all three sites. Different distributions of PDZ domain-containing proteins affect the development of autotypic junctions. In this review, we will describe PDZ domain-containing proteins at autotypic tight junctions in myelinating Schwann cells and their roles.
Current Medical Therapies for Osteoporosis and Its Alternative Treatments Using Natural Products
Oh, Seunghoon ; Ahn, Soon-Cheol ;
Journal of Life Science, volume 25, issue 1, 2015, Pages 113~120
DOI : 10.5352/JLS.2015.25.1.113
Osteoporosis is a major bone disorder defined as having bone mineral density (BMD) of 2.5 standard deviations or more below the peak bone mass. Osteoporosis will increasingly be a major disorder that faces the aging mankind. It is the result of an imbalance in the bone remodeling system, where bone constantly undergoes a cycle of resorption by osteoclasts and formation by osteoblasts. Estrogen deficiency in women following menopause is identified as the predominant reason that causes disparity in this system. Current medical treatments for osteoporosis include hormone replacement therapy (HRT), biphosphonates, and teriparatide, but have various side effects that raise questions concerning their medical safety and practicality. Alternative treatments involving natural product sources are under study to find a safer therapy. Many natural sources including lactoferrin and isoflavones and numerous traditional herbal medicines exhibit anti-resorptive or anabolic effects on bone and thus show promises to provide therapeutic agents in treating osteoporosis. Unfortunately, the majority of natural product treatments are still in its preliminary stages to prove their efficacy even though the development pace of treatment for osteoporosis is astounding in the past few decades. Further progress in pre-clinical studies and the subsequent clinical studies will someday lead to a breakthrough that takes us another step forward in science.