• IMMUNE NETWORK
• /
• v.1 no.2
• /
• pp.104-108
• /
• 2001

Aging is a senescence and defined as a normal physiologic and structural alterations in almost all organ systems with age. As Leonard Hayflick, one of the first gerontologists to propose a theory of biologic aging, indicated that a theory of aging or longevity satisfies the changes of above conditions to be universal, progressive, intrinsic and deleterious. Although a number of theories have been proposed, it is now clear that cell aging (cell senescence) is multifactorial. No single mechanism can account for the many varied manifestations of biological aging. Many theories have been proposed in attempt to understand and explain the process of aging. Aging is effected in individual by genetic factors, diet, social conditions, and the occurrence of age-related diseases as diabetes, hypertension, and arthritis. It involves an endogenous molecular program of cellular senescence as well as continuous exposure throughout life to adverse exogenous influences, leading to progressive infringement on the cell's survivability so called wear and tear. So we could say the basic mechanism of aging depends on the irreversible and universal processes at cellular and molecular level. The immediate cause of these changes is probably an interference in the function of cell's macromolecules-DNA, RNA, and cell proteins-and in the flow of information between these macromolecules. The crucial questions, unanswered at present, concerns what causes these changes in truth. Common theories of aging are able to classify as followings for the easy comprehension. 1. Biological, 1) molecular theories - a. error theory, b. programmed aging theory, c. somatic mutation theory, d. transcription theory, e. run-out-of program theory, 2) cellular theories - a. wear and tear theory, b. cross-link theory, c. clinker theory, d. free radical theory, e. waste product theory, 3) system level theory-a. immunologic/autoimmune theory, 4) others - a. telomere theory, b. rate of living theory, c. stress theory, etc. Prevention of aging is theoretically depending on the cause or theory of aging. However no single theory is available and no definite method of delaying the aging process is possible by this moment. The most popular action is anti-oxidant therapy using vitamin E and C, melatonin and DHEA, etc. Another proposal for the reverse of life-span is TCP-17 and IL-16 administration from the mouse bone marrow B cell line study for the immunoglobulin VDJ rearrangement with RAG-1 and RAG-2. Recently conclusional suggestion for the extending of maximum life-span thought to be the calory restriction.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.6
• /
• pp.781-787
• /
• 2017

Objective: The early growth response (Egr) family consists of four members (Egr1, Egr2, Egr3, and Egr4) that are zinc finger transcription factors. Among them, Egr3 is involved in transcriptional regulation of target genes during muscle spindle formation and neurite outgrowth. We previously showed that the immunoreactive Egr3 is localized on oocyte spindle and accumulate near the microtubule organizing center during meiosis I in mice. Egr3 was also shown to be localized on spermatocytes. We herein investigated if Egr3 is expressed in mouse gonads and if Egr3 blockade results in any defect in oocyte maturation. Methods: Expression of Egr3 in mouse gonads was examined by reverse transcription-polymerase chain reaction. Full-length Egr3 and truncated Egr3 (${\Delta}Egr3$) complementary RNAs (cRNAs) with Xpress tag at N-terminus and DsRed2 at C-terminus, and small interfering RNA (siRNA) targeting Egr3 were microinjected into mouse oocytes at germinal vesicle stage. Localization of microinjected Egr3 was examined by confocal live imaging and immunofluorescence staining. Results: Egr3 mRNA was detected in mouse ovaries and testes from 1 to 4 week-old mice. An uncharacterized longer transcript containing 5'untranslated region was also detected in 3 and 4 week-old gonads. Microinjected Xpress-Egr3-DsRed2 or Xpress-${\Delta}Egr3$-DsRed2 localized to nuclei and chromosomes during meiotic progression. Microinjection of these cRNAs or Egr3 siRNA in oocytes did not affect meiotic maturation. Immunofluorescence staining of Egr3 in Xpress-${\Delta}Egr3$-DsRed2-injected oocytes showed a positive signal only on meiotic spindle, suggesting that this antibody does not detect endogenous or exogenous Egr3 in mouse oocytes. Conclusion: The results show that Egr3 localizes to chromosomes during meiotic progression and that certain antibodies may not faithfully represent localization of target proteins in oocytes. Egr3 seems to be dispensable during oocyte maturation in mice.

• Development and Reproduction
• /
• v.2 no.2
• /
• pp.189-196
• /
• 1998

Several lines of evidence indicate that some neuropeptides classically associated hypothalamus have been found in pituitary gland, suggesting the existence of local regulation of pituitary function. Among the hypothalamic releasing hormones, genes for TRH and GnRH are expressed in the rat anterior pituitary gland. The present study was carried out to investigate the expression of the GHRH gene in rat anterior pituitary and the pituitary-derived cell lines. The presence of GHRH transcripts in pituitary tissue was shown by 3'rapid amplification of cDNA end (3'-RACE) analysis. In reverse transcription-polymerase chain reaction (RT-PCR) study, GHRH cDNA fragments were amplified from two pituitary-derived cell lines, $\alpha$T3 cells originated from mouse gonadotrope and GH3 cells from rat somatolactotrope. Immunoreactive GHRH was detected in large and medium-sized pituitary cells by immunocytochemistry. Significant amounts of GHRH-like molecules were found in the GH3 cell extracts. In RNase protection assay, the level of pituitary GHRH mRNA was augmented by ovariectomy. These results demonstrate that GHRH gene is expressed in the rat gonadotropes and somatotropes, and suggest that the pituitary GHRH could be participated in the paracrine and/or autocrine regulation of cell proliferation, as well as promoting growth hormone secretion.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.21 no.2
• /
• pp.169-182
• /
• 2005

The purpose of this study was to compare the stress distribution around the surrounding bone according to the splinted and non-splinted conditions on the finite element models of the two implant crowns with the different vertical bone level. The finite element model was designed with the parallel placement of the two fixtures ($4.0mm{\times}11.5mm$) with reverse buttress thread on the mandibular 1st and 2nd molars. As the bone quality, the inner cancellous bone and the outer 2 mm cortical bone were designed, and the cortical and cancellous bone were assumed to be perfectly bonded to the implant fixture. The splinted model(Model 1) had 2 mm contact surface and the non-splinted model(Model 2) had $8{\mu}m$ gap between two implant crowns. Two group (Splinted and non-splinted) was loaded with 200 N magnitude in the vertical and oblique directions on the loading point position on the central position of the crown, the 2 mm and 4 mm buccal offset point from the central position. Von Mises stress value was recorded and compared in the fixture-bone interface in the bucco-lingual and mesio-distal sections. The results were as follows; 1. In the vertical loading condition of central position, the stress was distributed on the cortical bone and the cancellous bone around the thread of the fixture in the splinted and non-splinted models. In the oblique loading condition, the stress was concentrated toward the cortical bone of the fixture neck, and the neck portion of 2nd molar in the non-splinted model was concentrated higher than that of 1st molar compared to the splinted model. 2. In the 2 mm buccal offset position of the vertical loading compared to the central vertical loading, stress pattern was shifted from apical third portion of the fixture to upper third portion of that. In the oblique loading condition, the stress was distributed over the fixture-bone interface. 3. In the 4 mm buccal offset position of the vertical loading, stress pattern was concentrated on the cortical bone around the buccal side of the fixture thread and shifted from apical third portion of the fixture to upper third portion of that in the splinted and non-splinted models. In the oblique loading, stresses pattern was distributed to the outer position of the neck portion of the fixture thread on the mesio-distal section in the splinted and non-splinted models. Above the results, it was concluded that the direction of loading condition was a key factor to effect the pattern and magnitude of stress over the surrounding bone of the fixture under the vertical and oblique loading conditions, although the type with or without proximal contact did not effect to the stress distribution.

• Korean Journal of Environmental Biology
• /
• v.20 no.3
• /
• pp.224-231
• /
• 2002

Photoperiod (length of light per day) is a major factor in regulating reproductive function in golden hamsters. The information of photoperiod is transmitted to the reproductive endocrine system by melatonin. Thus the effects of melatonin aye investigated in male golden hamsters exposed to photoperiods. Paired testicular weights were markedly reduced in the animals housed in short photoperiod $(SP,\le{12\;hours\;day^{-1})$ and injected with melatonin in the evening, but not in long photoperiod $(LP,\le{12.5}\;hours\;day^{-1})$ and injected with melatonin in the morning. The histological examination of regressed testes showed reduction of tubular lumen diameter including the numbers of cells and Leydig cell number. The mean values of both follicle stimulating hormone (FSH) and luteinizing hormone (LH) were also lowered in the sexually inactive animals than in the sexually active animals. Melatonin receptor was identified by reverse-transcription polymerase chain reaction (RT-PCR) and its expression was examined in various tissues to scrutinize the action site of melatonin. It turned out 309 nucleotides and was definitely expressed in hypothalamus and pituitary including spleen, retina, and epididymis. And gonadotropin releasing hormone (GnRH) gene, which is a key element in regulating reproduction, was identified by RT-PCR but the expression of GnRH was not modified by the treatment of melatonin. Taken together, photoperiod via melatonin indirectly affects reproductive endocrine system, possibly through the release of GnRH, not the synthesis of GnRH.

• Journal of Life Science
• /
• v.28 no.6
• /
• pp.733-737
• /
• 2018

Cucurbitacin-I, a natural triterpenoid derived from Cucurbitaceae family plants, exhibits a number of potentially useful pharmacological and biological activities. Indeed, the previous study demonstrated that cucurbitacin-I reduced the proliferation of colon cancer cells by enhancing apoptosis and causing cell cycle arrest at the G2/M phase. CD44, a type I transmembrane protein with the function of adhering to cells, mediates between the extracellular matrix and other cells through hyaluronic acid. Recent studies have demonstrated that an overexpression of the CD44 membrane receptor results in tumor initiation and growth, specific behaviors of cancer stem cells, the development of drug resistance, and metastasis. The aim was to examine the effect of cucurbitacin-I on CD44 expression human ovarian cancer cells because the effect of cucurbitacin-I on CD44 expression has not been reported. The expressions of CD44 mRNA and protein were detected using a quantitative real-time reverse-transcription polymerase chain reaction and a Western blot analysis, respectively. Treatment with cucurbitacin-I inhibited the expression of CD44 mRNA and protein. A subsequent analysis revealed that cucurbitacin-I blocked the phosphorylation of activator protein-1 (AP-1) and nuclear factor kappa-B ($NF-{\kappa}B$), which are key regulators of CD44 expression. Taken together, the data demonstrate that cucurbitacin-I regulates the AP-1 and $NF-{\kappa}B$ signaling pathways, leading to decreased CD44 expression.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.9
• /
• pp.4214-4223
• /
• 2012

The argument related to the use of real and anonymous names on the Internet bulletin board has recently become a main issue. When using real names, it is possible to violate free discussion and privacy. Also, when using anonymous names, it is possible to have the reverse function of the Internet in regard to the use of malicious replies or the distribution of false ideas. Therefore, this paper has made it possible to prevent the spread of the user's personal information and execute the single log-in process by using the XML-token method which is one of the SSO technologies. Also, by issuing virtual IDs and forming the path when establishing tokens, the anonymous bulletin board which provides anonymity with a conditional tracing process has been suggested. After analyzing the performance of visitor numbers at authentication time, the anonymous bulletin board based on the group signature method showed the average response rate of 0.72 seconds, 0.18 seconds, which was suggested scheme. In the authentication time 4-5 times faster response speed, respectively. Also, since the suggested system does not have to provide a single authentication process or make the user provide his or her signature, the level of user's convenience seems to be much higher. Such a result shows that the system suggested on the anonymous bulletin board has a more appropriate level of user's convenience.

• BMB Reports
• /
• v.38 no.1
• /
• pp.58-64
• /
• 2005

Myo-inositol monophosphate phosphatase (IMPP) is a key enzyme in the phosphoinositide cell-signaling system. This study found that incubating the IMPP from a porcine brain with pyridoxal-5'-phosphate (PLP) resulted in a time-dependent enzymatic inactivation. Spectral evidence showed that the inactivation proceeds via the formation of a Schiff's base with the amino groups of the enzyme. After the sodium borohydride reduction of the inactivated enzyme, it was observed that 1.8 mol phosphopyridoxyl residues per mole of the enzyme dimer were incorporated. The substrate, myo-inositol-1-phosphate, protected the enzyme against inactivation by PLP. After tryptic digestion of the enzyme modified with PLP, a radioactive peptide absorbing at 210 nm was isolated by reverse-phase HPLC. Amino acid sequencing of the peptide identified a portion of the PLP-binding site as being the region containing the sequence L-Q-V-S-Q-Q-E-D-I-T-X, where X indicates that phenylthiohydantoin amino acid could not be assigned. However, the result of amino acid composition of the peptide indicated that the missing residue could be designated as a phosphopyridoxyl lysine. This suggests that the catalytic function of IMPP is modulated by the binding of PLP to a specific lysyl residue at or near its substrate-binding site of the protein.

• Development and Reproduction
• /
• v.8 no.1
• /
• pp.49-55
• /
• 2004

Aquaporins(AQPs) are a family of transmembrane water channel proteins that are widely distributed in various tissues throughout the body and play a major role in Oanscellular and Oansepithelial water movement. Uterine endometrium undergoes recurrent uterine stromal edema in response to hormonal stimuli, however, the mechanism regulating the fluid transport during the estrous cycle has not been fully understood. To investigate the possible role of AQPs in water movement in uterus during the estrous cycle, expression patterns of AQP -1, -3, -4, -5, -8, and -9 UMh in mouse uterus were analyzed by using semiquantitative reverse transcription- polymerase chain reaction(RT-nR). We employed a combination of laser capture microdissection(LCM) and RT-PCR to examine the expression patterns in specific uterine cell types luminal epithelial cells(LE) and stromal cells(S). Our results showed that the level of AQP-4 mRNA was significantly increased while the level of AQP-3 mRNA was significantly decreased during the proestous through the estrus stage. In addition LCM revealed that AQP-4 and -8 mRNAs were highly expressed in LE compared with S. Taken together, these results suggest that AQPs may have an important function in physiological changes of mouse uterus during the estrous cycle.

• Nutrition Research and Practice
• /
• v.9 no.2
• /
• pp.129-136
• /
• 2015

BACKGROUND/OBJECTIVES: A variety of immunomodulators can improve the efficacy of low-dose chemotherapeutics. Active hexose correlated compound (AHCC), a mushroom mycelia extract, has been shown to be a strong immunomodulator. Whether AHCC could enhance the antitumor effect of low-dose 5-fluorouracil (5-FU) via regulation of host immunity is unknown. MATERIALS/METHODS: In the current study Hepatoma 22 (H22) tumor-bearing mice were treated with PBS, 5-FU ($10mg{\cdot}kg^{-1}{\cdot}d^{-1}$, i.p), or AHCC ($360mg{\cdot}kg^{-1}{\cdot}d^{-1}$, i.g) plus 5-FU, respectively, for 5 d. $CD^{3+}$, $CD^{4+}$, $CD^{8+}$, and NK in peripheral blood were detected by flow cytometry. ALT, AST, BUN, and Cr levels were measured by biochemical assay. IL-2 and $TNF{\alpha}$ in serum were measured using the RIA kit and apoptosis of tumor was detected by TUNEL staining. Bax, Bcl-2, and TS protein levels were measured by immunohistochemical staining and mRNA level was evaluated by RT-PCR. RESULTS: Diet consumption and body weight showed that AHCC had no apparent toxicity. AHCC could reverse liver injury and myelosuppression induced by 5-FU (P < 0.05). Compared to mice treated with 5-FU, mice treated with AHCC plus 5-FU had higher thymus index, percentages of $CD^{3+}$, $CD^{4+}$, and NK cells (P < 0.01), and ratio of $CD^{4+}$/$CD^{8+}$ (P < 0.01) in peripheral blood. Radioimmunoassay showed that mice treated with AHCC plus 5-FU had the highest serum levels of IL-2 and $TNF{\alpha}$ compared with the vehicle group and 5-FU group. More importantly, the combination of AHCC and 5-FU produced a more potent antitumor effect (P < 0.05) and caused more severe apoptosis in tumor tissue (P < 0.05) compared with the 5-FU group. In addition, the combination of AHCC and 5-FU further up-regulated the expression of Bcl-2 associated X protein (Bax) (P < 0.01), while it down-regulated the expression of B cell lymphoma 2 (Bcl-2) (P < 0.01). CONCLUSIONS: These results support the claim that AHCC might be beneficial for cancer patients receiving chemotherapy.