Liver regeneration is a well-known systemic homeostatic phenomenon. The N6-methyladenosine (m6A) modification pathway has been associated with liver regeneration and hepatocellular carcinoma. m6A methyltransferases, such as methyltransferase 3 (METTL3) and methyltransferase 14 (METTL14), are involved in the hepatocyte-specific-regenerative pathway. To illustrate the role of METTL14, secreted from non-parenchymal liver cells, in the initiation phase of liver regeneration, we performed 70% partial hepatectomy (PH) in Mettl14 heterozygous (HET) and wild-type (WT) mice. Next, we analyzed the ratio of liver weight to body weight and the expression of mitogenic stimulators derived from non-parenchymal liver cells. Furthermore, we evaluated the expression of cell cycle-related genes and the hepatocyte proliferation rate via MKI67-immunostaining. During regeneration after PH, the weight ratio was lower in Mettl14 HET mice compared to WT mice. The expressions of hepatocyte growth factor (HGF) and tumor necrosis factor (TNF)-α, mitogens derived from non-parenchymal liver cells that stimulate the cell cycle, as well as the expressions of cyclin B1 and D1, which regulate the cell cycle, and the number of MKI67-positive cells, which indicate proliferative hepatocyte in the late G1-M phase, were significantly reduced in Mettl14 HET mice 72 h after PH. Our findings demonstrate that global Mettl14 mutation may interrupt the homeostasis of liver regeneration after an acute injury like PH by restraining certain mitogens, such as HGF and TNF-α, derived from sinusoidal endothelial cells, stellate cells, and Kupffer cells. These results provide new insights into the role of METTL14 in the clinical treatment strategies of liver disease.
Ko, Eul-Bee;Jang, Yin-Gi;Kim, Cho-Won;Go, Ryeo-Eun;Lee, Hong Kyu;Choi, Kyung-Chul
Biomolecules & Therapeutics
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제30권2호
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pp.151-161
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2022
This study elucidates the anti-cancer potential of gallic acid (GA) as a promising therapeutic agent that exerts its effect by regulating the PI3K/Akt pathway. To prove our research rationale, we used diverse experimental methods such as cell viability assay, colony formation assay, tumor spheroid formation assay, cell cycle analysis, TUNEL assay, Western blot analysis, xenograft mouse model and histological analysis. Treatment with GA inhibited cell proliferation in dose-dependent manner as measured by cell viability assay at 48 h. GA and cisplatin (CDDP) also inhibited colony formation and tumor spheroid formation. In addition, GA and CDDP induced apoptosis, as determined by the distribution of early and late apoptotic cells and DNA fragmentation. Western blot analysis revealed that inhibition of the PI3K/Akt pathway induced upregulation of p53 (tumor suppressor protein), which in turn regulated cell cycle related proteins such as p21, p27, Cyclin D1 and E1, and intrinsic apoptotic proteins such as Bax, Bcl-2 and cleaved caspase-3. The anti-cancer effect of GA was further confirmed in an in vivo mouse model. Intraperitoneal injection with GA for 4 weeks in an A549-derived tumor xenograft model reduced the size of tumor mass. Injection of them downregulated the expression of proliferating cell nuclear antigen and p-Akt, but upregulated the expression of cleaved caspase-3 in tumor tissues. Taken together, these results indicated that GA hindered lung cancer progression by inducing cell cycle arrest and apoptosis, suggesting that GA would be a potential therapeutic agent against non-small cell lung cancer.
Cell transformation induced by epidermal growth factor (EGF) and 12-O-tetradecanoylphorbol-13-acetate (TPA) is a critical event in cancer initiation and progression, and understanding the underlying mechanisms is essential for the development of new therapeutic strategies. Licorice extract contains various bioactive compounds, which have been reported to have anticancer and anti-inflammatory effects. This study investigated the cancer preventive efficacy of licochalcone D (LicoD), a chalcone derivative in licorice extract, in EGF and TPA-induced transformed skin keratinocyte cells. LicoD effectively suppressed EGF-induced cell proliferation and anchorage-independent colony growth. EGF and TPA promoted the S phase of cell cycle, while LicoD treatment caused G1 phase arrest and down-regulated cyclin D1 and up-regulated p21 expression associated with the G1 phase. LicoD also induced apoptosis and increased apoptosis-related proteins such as cleaved-caspase-3, cleaved-caspase-7, and Bax (Bcl2-associated X protein). We further investigated the effect of LicoD on the AKT signaling pathway involved in various cellular processes and found decreased p-AKT, p-GSK3β, and p-NFκB expression. Treatment with MK-2206, an AKT pharmacological inhibitor, suppressed EGF-induced cell proliferation and transformed colony growth. In conclusion, this study demonstrated the potential of LicoD as a preventive agent for skin carcinogenesis.
Hyuk Cheol Kwon;Hyun Su Jung;Do Hyun Kim;Jong Hyeon Han;Seo Gu Han;Dong Hyun Keum;Seong Joon Hong;Sung Gu Han
Animal Bioscience
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제36권11호
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pp.1757-1768
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2023
Objective: The number of bovine mammary epithelial cells (BMECs) is closely associated with the quantity of milk production in dairy cows; however, the optimal levels and the combined effects of hormones and essential amino acids (EAAs) on cell proliferation are not completely understood. Thus, the purpose of this study was to determine the optimal combination of individual hormones and EAAs for cell proliferation and related signaling pathways in BMECs. Methods: Immortalized BMECs (MAC-T) were treated with six hormones (insulin, cortisol, progesterone, estrone, 17β-estradiol, and epidermal growth factor) and ten EAAs (arginine, histidine, leucine, isoleucine, threonine, tryptophan, lysine, methionine, phenylalanine, and valine) for 24 h. Results: Cells were cultured in a medium containing 10% fetal bovine serum (FBS) as FBS supplemented at a concentration of 10% to 50% showed a comparable increase in cell proliferation rate. The optimized combination of four hormones (insulin, cortisol, progesterone, and 17β-estradiol) and 20% of a mixture of ten EAAs led to the highest cell proliferation rate, which led to a significant increase in cell cycle progression at the S and G2/M phases, in the protein levels of proliferating cell nuclear antigen and cyclin B1, cell nucleus staining, and in cell numbers. Conclusion: The optimal combination of hormones and EAAs increased BMEC proliferation by enhancing cell cycle progression in the S and G/2M phases. Our findings indicate that optimizing hormone and amino acid levels has the potential to enhance milk production, both in cell culture settings by promoting increased cell numbers, and in dairy cows by regulating feed intake.
To compare and analyze the improvement effects of white ginseng extract, red ginseng extract, and black ginseng extract on cognitive dysfunction and memory impairment caused by scopolamine in rats. In the cognitive behavioral test, the tendency of the SCOP+B group to overcome the escape time delay induced by scopolamine administration was observed, unlike the SCOP group. The frequency on plat form was significantly increased in the group treated with ginseng extracts compared to the SCOP group. As a result of measuring the duration time on goal quadrant, the time spent in the quadrant was significantly increased in the SCOP+B group compared to the SCOP group. In the hippocampus, the SCOP-treated group significantly decreased the activity of AChE compared to the normal group, but the ginseng extract-treated groups significantly increased it compared to the SCOP group. After sacrificing the rats after the behavioral test, the expression of PSD95 protein in the excised brain was significantly decreased in the SCOP group compared to normal, but it was observed that the SCOP+R and SCOP+B groups were significantly increased compared to the SCOP group. CREB1 protein expression was significantly increased in the SCOP+R group, and the expression of Cdk5 was significantly increased in the SCOP+B group. Ginseng extracts significantly restored the memory damaged by scopolamine suggesting that red ginseng increased the expression of CREB1 and PSD95 proteins, and black ginseng increased the protein expression of Cdk5 and PSD95 to induce memory recovery.
Due to the continuous increase in patients with androgenetic alopecia (AGA) and psychological disorders such as depression and anxiety, the demand for hair loss treatment and effective hair growth materials has increased. Terminalia bellirica (Gaertn.) Roxb. (TBE) reportedly exerts anti-inflammatory, hepatoprotective, and antidiabetic effects, among others, but its effects on testosterone (TS)-inhibited hair growth remains unclear. In this study, we evaluated the effects of TBE on TS-induced hair growth regression in human follicle dermal papilla cells (HFDPCs) and C57BL/6 mice. Oral administration of TBE increased TS-induced hair growth retardation. Interestingly, effects were greater when compared with finasteride, a commercial hair loss treatment product. Histological analyses revealed that oral TBE administration increased hair follicles in the dorsal skin of C57BL/6 mice. Additionally, western blotting and immunofluorescence showed that oral TBE administration recovered the TS-induced inhibition of cyclin D1, proliferating cell nuclear antigen (PCNA), and Ki67 expression in vivo. Using in vitro proliferation assays, TBE promoted HFDPC growth, which was suppressed by TS treatment. Thus, TBE may be a promising nutraceutical for hair health as it promoted hair growth in AGA-like in vitro and in vivo models.
Fewer than 20% of patients diagnosed with pancreatic cancer can be treated with surgical resection. The effects of proton beam irradiation were evaluated on the cell viabilities in Panc-1 and Capan-1 pancreatic cancer cells. The cells were irradiated with proton beams at the center of Bragg peaks with a 6-cm width using a proton accelerator. Cell proliferation was assessed with the MTT assay, gene expression was analyzed with semi-quantitative or quantitative reverse transcription-polymerase chain reaction analyses and protein expression was evaluated by western blotting. The results demonstrated that Capan-1 cells had lower cell viability than Panc-1 cells at 72 h after proton beam irradiation. Furthermore, the cleaved poly (ADP-ribose) polymerase protein level was increased by irradiation in Capan-1 cells, but not in Panc-1 cells. Additionally, it was determined that histone H2AX phosphorylation in the two cell lines was increased by irradiation. Although a 16 Gy proton beam was only slightly up-regulated cyclin-dependent kinase inhibitor 1 (p21) protein expression in Capan-1 cells, p21 expression levels in Capan-1 and Panc-1 cells were significantly increased at 72 h after irradiation. Furthermore, it was observed that the expression of DNA repair protein RAD51 homolog 1 (RAD51), a homogenous repair enzyme, was decreased in what appeared to be a dose-dependent manner by irradiation in Capan-1 cells. Contrastingly, the transcription of survivin in Panc-1 was significantly enhanced. The results suggest that RAD51 and survivin are potent markers that determine the therapeutic efficacy of proton beam therapy in patients with pancreatic cancer.
The microbiome has recently attracted research interest in a variety of subjects, including cancer. In the present study, it was determined that reinforced clostridium media (RC M) for microbiome culture, exerts antitumor effects on renal cell carcinoma cells when compared to the microbiome 'X'. The antitumor effects of RC M were investigated for all ingredients of RC M, and the results revealed that yeast extract could be a candidate for the ingredient driving this phenomenon. Further experiments including MTT assay, cell counting, cell death analysis, cell cycle analysis and western blotting were conducted with yeast extract on renal cell carcinoma cells (Caki-1 and Caki-2) and normal human proximal tubular cells (HK-2). As a result, yeast extract exhibited dose-dependent antitumor effects on Caki-1 and Caki-2, but only slight effects on HK-2. In addition, yeast extract only exhibited slight effects on necrosis, autophagy, or apoptosis of Caki-1 and Caki-2. Yeast extract produced cell cycle arrest with an increased G0/G1 fraction and a decreased S fraction, and this was considered to be related to the decreased cyclin D1. Although yeast extract treatment increased anti-oxidant activities, the antitumor effects of yeast extract were also related to iron metabolism, based on the decreased transferrin receptor and increased ferritin. In addition, decreased GPX4 may be related to iron-dependent cell death, particularly in Caki-2. These results revealed that yeast extract may inhibit proliferation of renal cell carcinoma cells by regulating iron metabolism. Since an increased iron requirement is a classic phenomenon of cancer cells, yeast extract may be a candidate for adjuvant treatment of renal cell carcinoma.
Reversine, a 2,6-diamino-substituted purine analogue, has been reported to be effective in tumor suppression via induction of cell growth arrest and apoptosis of cancer cells. However, it remains unclear whether reversine exerts anticancer effects on human colorectal cancer cells. In the present study, in vitro experiments were conducted to investigate the anticancer properties of reversine in human colorectal cancer cells. The effect of reversine on human colorectal cancer cell lines, SW480 and HCT-116, was examined using a WST-1 cell viability assay, fluorescence microscopy, flow cytometry, DNA fragmentation, small interfering RNA (siRNA) and western blotting. Reversine treatment demonstrated cytotoxic activity in human colorectal cancer cells. It also induced apoptosis by activating poly(ADP-ribose) polymerase, caspase-3, -7 and -8, and increasing the levels of the pro-apoptotic protein second mitochondria-derived activator of caspase/direct inhibitor of apoptosis-binding protein with low pI. The pan-caspase inhibitor Z-VAD-FMK attenuated these reversine-induced apoptotic effects on human colorectal cancer cells. Additionally, reversine treatment induced cell cycle arrest in the subG1 and G2/M phases via increase in levels of p21, p27 and p57, and decrease in cyclin D1 levels. The expression of Fas and death receptor 5 (DR5) signaling proteins in SW480 and HCT116 cells was upregulated by reversine treatment. Reversine-induced apoptosis and cell cycle arrest were suppressed by inhibition of Fas and DR5 expression via siRNA. In conclusion, Reversine treatment suppressed tumor progression by the inhibition of cell proliferation, induction of cell cycle arrest and induction of apoptosis via upregulation of the Fas and DR5 signaling pathways in human colorectal cancer cells. The present study indicated that reversine may be used as a novel anticancer agent in human colorectal cancer.
Seonjeong Park;Seung A Ock;Yun Jeong Park;Sung Nim Han;Sunhye Shin
Journal of Nutrition and Health
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제57권4호
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pp.376-388
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2024
Purpose: Adipocyte dysfunction has been reported in diabetes, and stimulating thermogenesis and suppressing senescence in adipocytes potentially alleviates metabolic dysregulation. This study aimed to investigate thermogenesis and cellular senescence in diabetic adipocytes under basal conditions and in response to stimuli. Methods: White and brown primary adipocytes derived from control (CON) and db/db (DB) mice were treated with β-agonists, such as norepinephrine (NE) and CL316,243, and 18-carbon fatty acids, including stearic acid, oleic acid (OLA), linoleic acid (LNA), and α-linolenic acid, and the expression of the genes related to thermogenesis and cellular senescence was measured. Results: Although no difference in the thermogenic and cellular senescence gene expression in white adipose tissue (WAT) was noted between the CON and DB mice, brown adipose tissue (BAT) from the DB mice exhibited lower uncoupling protein 1 (Ucp1) expression and higher cyclin-dependent kinase inhibitor (Cdkn)1a and Cdkn2a expression levels compared to that from the CON mice. Stromal vascular cells isolated from the BAT of the DB mice displayed higher peroxisome proliferator-activated receptor gamma (Pparg), CCAAT/enhancer-binding protein alpha (Cebpa), Cdkn1a, and Cdkn2a expression levels. White adipocytes from the DB mice exhibited lower Ucp1, peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (Pgc1a), and PR domain containing 16 (Prdm16) expression levels regardless of β-agonist treatment. NE upregulated Pgc1a in both white and brown adipocytes from the CON mice, but not in those from the DB mice. Although none of the fatty acids were observed to downregulate the cellular senescence genes in fully differentiated adipocytes, the OLA-treated brown adipocytes derived from DB mice exhibited lower Cdkn1a and Cdkn2b expression levels than the LNA-treated cells. Conclusion: These results indicate that the lower thermogenic capacity of diabetic adipocytes may be related to their cellular senescence, and different fatty acids potentially exert divergent effects on the expression of cellular senescence genes.
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