In this review, the regulatory mechanisms of autophagy were described, and its interaction with apoptosis was identified. The role of autophagy in embryogenesis, tooth development, and cell differentiation were also investigated. Autophagy is regulated by various autophagy-related genes and those related to stress response. Highly active autophagy occurrences have been reported during cell differentiation before implantation after fertilization. Autophagy is involved in energy generation and supplies nutrients during early birth, essential to compensate for their deficient supply from the placenta. The contribution of autophagy during tooth development, such as the shape of the crown and root formation, ivory, and homeostasis in cells, was also observed. Genes control autophagy, and studying the role of autophagy in cell differentiation and development was useful for understanding human aging, illness, and health. In the future, the role of specific mechanisms in the development and differentiation of autophagy may increase the understanding of the pathological mechanisms of disease and development processes and is expected to reduce the treatment of various diseases by modulating the autophagic phenomenon.

Alpha-linolenic acid is an important polyunsaturated fatty acid that exhibits anticancer, anti-inflammatory, and antioxidative effects. In this study, we investigated the protective effects of alpha-linolenic acid on the cell proliferation and differentiation of C2C12 cells under essential amino acid-deficient conditions. Different concentrations of alpha-linolenic acid and essential amino acids were added to the growth and differentiation media. The concentrations of 10 μM of alphalinolenic acid and 2% essential amino acid were chosen for subsequent experiments. Supplementation with alpha-linolenic acid and essential amino acids improved the proliferation and differentiation of C2C12 cells and significantly increased the mRNA levels of catalase, superoxide dismutase, B-cell lymphoma-2, and beclin-1 as well as the protein levels of PPARγ coactivator-1α compared to those in the controls. Moreover, supplementation with alpha-linolenic acid and essential amino acids reduced the levels of phosphorylated H2A.X variant histone, Bcl-2-associated X, p53, and light chain 3 during C2C12 cell proliferation, and increased the expression levels of myogenic factors 4 (myogenin) and 5 during C2C12 cell differentiation. Overall, we determined that alpha-linolenic acid and essential amino acids maintained the cell proliferation and differentiation of C2C12 cells via their anti-oxidative, anti-apoptotic, and anti-autophagic effects.

Stem cells have special properties, such as self-renewal, proliferation, and the multilineage differentiation. Generally, stem cells are categorized into embryonic stem cells (ESCs), adult stem cells (ASCs), and induced pluripotent stem cells (iPSCs). Mesenchymal stem cells (MSCs) are a type of ASCs with a multipotent property. MSCs are easily isolated from various tissues and organs in the human body and can differentiation into multiple lineages, such as bone, cartilage, fat, and muscles. Compared to ESCs and iPSCs, MSCs possess less proliferation and differentiation capacities, therefore, a much scientific concern is concerned toward promoting the proliferation and the differentiation potency of MSCs. There are various methods to achieve this goal such as the treatment of various types of small molecules or culturing on specific peptides. Producing of high-quality MSCs with enhanced proliferation and differentiation capacities will definitely be a useful tool for stem cell-mediated tissue regeneration and the further clinical application.

Nicotine of tobacco component has a controversial impact in the clinical outcome of dental implants. Although numerous nicotine effects on bone healing around implants have been presented, it is rarely reported in vitro study about normal human osteoblast(NHost) from oral and maxillofacial area at the surface of implants. The purpose of the present study was to evaluate the effect of nicotine on the proliferation and differentiation response of NHost to plasmatic and salivary levels of nicotine reported in smokers at the surface of screw-type plasma-sprayed titanium implants. NHosts were seeded on the surface of titanium implants and cultured for 21 days in α-MEM supplemented with 10% FBS, 50mg/ml ascorbic acid, 5mM β-glycerophosphate and 100nM dexamethasone. Seeded implants were exposed to various nicotine concentration(0.05-0.5mg/ml) from 1 to 21 days, and characterized for cell morphology, proliferation, differentiation, alkaline phosphatase(ALP) activity and ionized calcium concentration(Cai) of medium. Continuous exposure to higher nicotine concentration(above 0.3mg/ml) induced a dose- and time-dependent vacuolation of the cytoplasm, and a tendency to detach from the implant surface. 0.05mg/ml(lower nicotine concentration) did not cause significant effects in the cell proliferation and ALP activity. 0.1-0.2mg/ml caused evident dose-dependent effects in increased cell proliferation, ALP activity and earlier onset of matrix mineralization at levels up to 0.2mg/ml, while a dose-dependent inhibitory effect at 0.3-0.5mg/ml. Cai concentration of control group was decreased at 14 days. Increased Cai concentration at 0.1-0.2mg/ml, decreased Cai concentration at 0.3mg/ml and no change at 0.5mg/ml during the culture period were seen. It suggested that nicotine concentration could paly an role in modulating NHost activity as a contributing factor associated with proliferation and differentiation of NHost at the surface of implants.

Recently, extensive research has been performed in the field of orthopedic medicine to develop cell-based therapies for the restoration of injured bone tissue. But there has been rarely reported about rehabilitaton of oral and maxillofacial bone defect using self-derived osteoblasts. Normal human osteoblast cell(NHost) was previously established into marrow-derived human mesenchymal stem cells for their capacity to proliferate and differentiate into osteoblasts under various culture conditions. The purpose of this study was to examine proliferation and differentiation of NHosts effected by growth factors with ALP activity and RT-PCR. After NHosts were cultured under basal and osteogenic medium at 37℃ and 5% CO2, they were analyzed by ALP activity and RT-PCR. BMP-2 under osteogenic medium decreased growth rate of NHosts compared to under osteogenic medium. BMP-2 under osteogenic medium induced osteoblastic differentiation in NHosts by increased ALP activity. The differentiating capacity of NHosts under osteogenic medium showed that NHosts expressed higher mRNA expression levels of OSX and OCN, while that of RUNX2 decreased after BMP-2 treatment. It suggested that NHosts having characteristics of osteoprecursor cells might be more advanced in their osteogenesis development by BMP-2, making NHosts an interesting biological tool for treatment of skeletal defects and diseases of oral and maxillofacial bone.

Cyclosporine A (Cs A) which is a highly lipophilic cyclic undecapeptide mainly used for its immunosuppressive properties exert a wide spectrum of biological activities including fungicidal antiproliferactive, anti-inflammatory and chemotherapuetic effects. Human salivary gland adenocarcinoma is very aggressive characteristics, which is need to get the effective chemotherapuetic methods. Subconfluent SGT cell cultures have been treated with CsA at in vivo relevant concentrations for 24h. MTT assay for cellular proliferation of cultured SGT cell line has been performed and TGase 1 activity assay for cellular differentiation has been detected in the CsA-treated samples. It suggested that CsA could have an inhibitory effect in the proliferation of SGT cell line but no in the differentiation.

Mammalian Emx2. a homeobox tra nscripti on factor‘ is continuoll s ly expressecl in aclll lt neural s tem cell s of the b.ippo campal c1enclate gyrus (HDG) a f'ter blrth 1'0 c1ate‘ roles 01' Emx2 a ncl its llnderlying rnecha ni s rn in r eg비 atin g acl lllt neuro - genesis from neural stem cell aft er bi rth is still obscure. 1'he present experiment is aimed to elucidate role 01' Emx2 in regulating adll lt neurogenesis from neural s tem cell of HDG using nestin-Emx2 transgenic mouse (N-E2 1'G) and heterozygous Emx2 KO mouse (1-l-E2 KO) . HDG g ranlllar cell layer where new born neurons proclllced from adult neural stem cell migrate. is thin with low cell c1ens ity in N-E2 1'G but tbick with high cell density in H-E2 KO, compared to wild type mice (\\끼') . Number of DCX , a new born nellron marker. -positive cells is less in N-E2 1'G but more in l-l-E2 KO. comparecl to W1'. Ki67 (whole cell cycle marker) 01' BrclU (S-phase marker) 一positive cells is less in N-E2 1'G bllt morc in l-l-E2 KO and BrdU-positive cells/ Ki 67ratio is higher in N-E2 1'G but lower in H-E2 KO. NeuN (a mature n e llro삐 marker) a ncl BrdU-dollble positive cells is lUore in N- E2 TG bllt GFAP (a glial cell marker) ancl BrdU- dollble positive cells is more in ]-]- E2 KO. compa recl to WT 4wks after BrclU is aclmin istratecl one ti me per c1ay for 5days‘ Migrating c1egree of BrdU-positive cells is lower in N-E2 TG but higher in ]-]-E2 KO 4wks after BrclU is administratecl one t ime per day for 5days. Active casepase 3-positive cells is more in ]-]DG 01' the N-E2 TG but no changes in ]-]-E2 KO. 4 wks after CAG- GFP- PRE vector was inj ected in hippocampus. GFP-positive new born n e urons from aclult neural stem cell have less c1endritic branches in N-E2 1'G but more c1endritic branches in H-E2 KO‘ comparecl to the WT From these results. Emx2 transcription factor inhibits adult neurogenesis f'rom nellral stem cell of HDG throllgh reducing neural stem cell proliferation. new born cell survival. ce ll migration. ancl matllrat ion

NOD/SCID 마우스는 선천성 면역결핍을 지닌 마우스로서 이종 세포 및 조직 이식을 위한 실험동물로서 가장 많이 활용되고 있다. 본 연구는 돼지의 골수조직에서 채취한 조혈줄기세포를 면역결핍마우스의 정맥 주입을 통하여 생체 내 주입을 실시한 결과, 마우스의 조혈조직에서 대단히 높은 돼지 T 면역세포의 증식이 관찰되었다. 유세포 분석기를 이용해 돼지 골수 조혈세포 생체 이식 6주의 마우스에서의 돼지 T 면역세포의 증식과 분화 특성을 분석한 결과, 마우스 조혈조직인 골수(5.4±1.9%), 비장(15.4±7.3%), 간(21.3±1.4%), 림프절(33.5±32.8%)에서 돼지 조혈줄기세포 유래 T 세포의 증식과 분화가 관찰되었고, 돼지 helper T 세포와 cytotoxic T 세포의 발달도 확인되었다. 또한 조직 면역염색을 통하여 마우스의 비장조직에 이식한 돼지 면역세포의 증식을 관찰하였다. 본 연구는 NOD/SCID 마우스를 이용해 돼지 조혈줄기세포로부터 T 면역세포로의 분화 및 발달과정을 생체 내에서 분석할 수 있는 유용한 동물모델로서 이용할 수 있음을 보여준다.

Previous ly we have s hown that fï brob last• growth factor-2 (FGF-2) and dexamethasone (Dex) in combination strongly stimulate both p l 이 i fe rati o n a nd differe nt iation of mesenchymal stem cells (MSCs) into osteoblasts and adipocytes, In the present s tudy we invesL igaLed whether inhibition 01' FGF-2 and Dex-induced adipogenic differentiation of bone marrow derived s Lem cells (BMSCs) by GW9662, an antagoni s t of proxisome proliferators-activated receptol γ (PPARy) which plays a key role in ad ipogenic differentiation , enhances proliferation and osteoblastic differentiation of BMSCs Proliferation 01' BMSCs t reated wi 네 FGF-2 a nd Dex was further increased by GW9662 up to 9,7, 10,6, and 7,2% at 3, 5, and 7 days of cul Lu re , Expansion of BMSCs with FGF-2, Dex and GW9662 followed by osteoblastic different iation showed that osteoblas tic differentiation 01' BMSCs was in creased by 37 % (p=O, 01) compared to those expanded with FGF-2 and Dex, ln contrast , ad i pogenic di fferenti a tion of FGF-2 and Dex-expanded BMSCs was substantially reduced to 14% (p=O, 036) by GW9662, Taken toget her , these resul ts demonstrate that FGF-2 and Dex in combination with GW9662 f ur t her stimu late proliferation 01' BMSCs and those cells expanded with these factors acquire enhanced potentiaIs to be dif ferentiated i n to osteoblas ts

고령사회에서 노년기 건강의 큰 문제로 대두되고 있는 골다공증은 특히 폐경 후 여성들에게서 가장 그 발생빈도가 높게 나타났으며, 현재 골다공증 예방 및 치료에 사용되고 있는 약제는 대부분 골흡수 억제제로써 진행된 골소실을 회복 시킬 수는 없기 때문에 골형성 증가를 통한 골다공증 예방과 치료에 관한 연구가 활발히 이루어지고 있다. 산양삼(cultivated wild Panax ginseng, CWP)에 대한 연구는 다수가 원기회복, 자양강장 및 면역증강 효과 등에 대한 것이나 골대사에 미치는 영향에 대한 연구는 거의 없는 실정이다. 이에 본 연구에서는 산양삼 추출물이 조골세포에서 골관련 유전자 발현에 미치는 영향을 확인함으로써 골다공증 예방 및 치료 효과를 갖는 천연 소재로의 활용 가능성을 검토하고자 하였다. 산양삼 추출물 처리가 조골 세포 의 증식에 미치는 영향을 알아보기 위해 MTT assay를 실시하였고, MC3T3-E1 세포생존률은 FBS가 첨가되지 않은 배양액만 처리한 대조군과 산양삼 추출물을 처리한 실험군 모두에서 동일한 수준으로 나타났으며 이로써 산양삼 추출물의 안전성을 확인할 수 있었다. 또한 산양삼 추출물을 처리한 실험군과 대조군과의 세포증식률을 비교하였을 때 산양삼 추출물 50 ㎍/mL 농도 처리군에서 유의적으로 세포증식이 촉진되었으며 25 ㎍ /mL과 100 ㎍/mL 농도 처리군에서도 대조군보다 높은 경향을 나타내었다. 산양삼 추출물이 조골 세포의 활성에 미치는 영향을 알아보기 위해 조골세포의 분화초기 표지인자인 ALP 활성을 측정하였으며 그 결과 모든 산양삼 추출물 처리군이 대조군과 비교하여 유의적으로 높은 활성을 나타내었으며 특히 산양삼 추출물 50 ㎍/mL 농도 처리군에서 가장 높은 활성을 나타내었다. 산양삼 추출물의 농도에 따른 석회화 형성도를 확인하기 위해 무기질화된 세포의 기질을 alizarin red로 염색하였고 산양삼 추출물을 처리한 실험군과 대조군과의 석회화 형성도를 비교하였을 때 산양삼 추출물 50 ㎍/mL 농도 처리군에서 유의적으로 석회화 형성이 촉진되었으며 25 ㎍/mL과 100 ㎍/mL 농도 처리군에서도 대조군보다 높은 경향을 나타내었다. 산양삼 추출물이 MC3T3-E1 조골세포에서 골 형성 관련 유전자 발현에 미치는 영향을 확인하기 위해 Runx2, ALP, OPN, OCN 등의 유전자를 정량 real-time PCR을 통해 분석하였으며 대조군과 비교하여 모든 산양삼 추출물 처리군에서 농도 의존적이고 유의적으로 골 형성 관련 유전자발현이 증가되었다. 따라서 산양삼 추출물이 골 형성 관련 유전자인 Runx2, ALP, OPN, OCN 발현을 증가시켜 MC3T3-E1 조골세포의 분화를 촉진하고, 골 석회화 형성 촉진에 기여하였을 것으로 사료된다. 그러나 산양삼 추출물이 골형성과 관련하여 어떠한 기전으로 유전자의 발현을 조절하였는지에 대한 유전자 및 단백질 수준의 추가적인 연구와 산양삼 추출물의 분화 촉진과 석회화 형성능이 산양삼의 사포닌계 진세노사이드 성분의 영향인지에 대한 후속 연구가 필 요할 것으로 사료된다.

전세계적으로 널리 복용되고 있음에도 불구하고 인삼이 중추신경계에 미치는 효과에 대한 세포수준에서의 증거는 별로 없다. 따라서 본 연구자들은 지금까지 보고된 30여종 이상의 ginsenosides 중에서 인삼 효과의 주된 활성성분으로 알려져 있는 Rb1과 Rg1을 이용해 해마신경전구세포의 분화와 증식에 미치는 효과를 연구하였다. 증식실험결과 Rb1과 Rg1을 3일 동안 해마신경전구세포에 처리하면 대조군에 비해 BrdU(+)세포수가 상당히 감소한 반면에 분