1.Pharmacological mechanisms and effects of amino acid nutrients.
Chinese Journal of Gastrointestinal Surgery 2013;16(11):1123-1126
Common amino acid nutrients mainly contain glutamine, arginine, leucine, methionine and cysteine, which are not only the components participating in body protein synthesis, but also regulate the patients' immune system and metabolism. Glutamine can improve the intestinal barrier, reduce inflammatory reaction, and promote immunity recovery, but the clinical effects of different patients with different diseases are still lack of clear conclusions. The catabolism of arginine can produce NO, promoting the inflammatory reaction, and can also generate ornithine, alleviating inflammatory reaction and promoting wound healing. Two competing ways coexist, but the specific effects on different diseases have no clear conclusions yet. Leucine promotes muscle protein synthesis mainly through mTOR pathway, however, the influence on metabolism is still debating. Sulfur-containing amino acids methionine and cysteine can promote the synthesis of connective tissue and collagen conducive to wound healing, and their beneficial effects on lipid metabolism are of value. The purpose of this review is to cover potential beneficial physiological mechanisms of amino acid nutrients, to describe their results of clinical applications and to evaluate the interactions among individual nutrients or between individual nutrients and body.
Amino Acids
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pharmacology
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Humans
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Muscle Proteins
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Muscles
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Signal Transduction
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drug effects
;
TOR Serine-Threonine Kinases
2.Correlation between mTOR signaling transduction pathway and arsenic trioxide response.
Journal of Experimental Hematology 2010;18(1):54-56
This study was aimed to investigate the correlation between mTOR signaling transduction pathway and arsenic trioxide (ATO) effect. The expressions of pmTOR, pAKT and pP70S6K in K562/DNR treated with ATO for different time were detected by Western blot. The apoptosis rate of K562/DNR treated by ATO combined with LY294002 or rapamycin for 120 hours was assayed by flow cytometry. The results showed that the expression of pmTOR in K562/DNR cells treated with ATO for 60 minutes or 120 minutes was higher than that in the control group (p < 0.01); the expressions of pAKT in the cells treated with ATO for 30 minutes or 60 minutes were higher than that in the control group (p < 0.01); the expression of pP70S6K in the cells treated with ATO for 60 minutes was higher than that in the control group (p < 0.01). The apoptosis rate of K562/DNR cells treated with combination of ATO and LY294002 or rapamycin were higher than that in the control group. It is concluded that the mTOR signaling pathway in K562/DNR cells is activated by a certain concentration of ATO, and mTOR signaling pathway inhibitors enhance ATO to trigger apoptosis in K562/DNR cells.
Apoptosis
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drug effects
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Arsenicals
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pharmacology
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Humans
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K562 Cells
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Oxides
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pharmacology
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Signal Transduction
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TOR Serine-Threonine Kinases
;
metabolism
3.Effects of low-dose photodynamic therapy on the function of human adipose mesenchymal stem cells and its mechanism.
Yang YANG ; Lei LI ; Zeng Jun YANG ; Meng Xue ZHENG ; Wei Feng HE ; Rui YIN
Chinese Journal of Burns 2022;38(9):830-838
Objective: To investigate the effects of low-dose photodynamic therapy on the proliferation, regulation, and secretion functions of human adipose mesenchymal stem cells (ADSCs) and the related mechanism, so as to explore a new method for the repair of chronic wounds. Methods: The experimental research methods were adopted. From February to April 2021, 10 patients (5 males and 5 females, aged 23 to 47 years) who underwent cutaneous surgery in the Department of Dermatology of the First Affiliated Hospital of Army Medical University (the Third Military Medical University) donated postoperative waste adipose tissue. The cells were extracted from the adipose tissue and the phenotype was identified. Three batches of ADSCs were taken, with each batch of cells being divided into normal control group with conventional culture only, photosensitizer alone group with conventional culture after being treated with Hemoporfin, irradiation alone group with conventional culture after being treated with red light irradiation, and photosensitizer+irradiation group with conventional culture after being treated with Hemoporfin and red light irradiation, with sample number of 3 in each group. At culture hour of 24 after the treatment of the first and second batches of cells, the ADSC proliferation level was evaluated by 5-ethynyl-2'-deoxyuridine staining method and the migration percentage of HaCaT cells cocultured with ADSCs was detected by Transwell experiment, respectively. On culture day of 7 after the treatment of the third batch of cells, the extracellular matrix protein expression of ADSCs was detected by immunofluorescence method. The ADSCs were divided into 0 min post-photodynamic therapy group, 15 min post-photodynamic therapy group, 30 min post-photodynamic therapy group, and 60 min post-photodynamic therapy group, with 3 wells in each group. Western blotting was used to detect the protein expressions and calculate the phosphorylated mammalian target of rapamycin complex (p-mTOR)/mammalian target of rapamycin (mTOR), phosphorylated p70 ribosomal protein S6 kinase (p-p70 S6K)/p70 ribosomal protein S6 kinase (p70 S6K) ratio at the corresponding time points after photodynamic therapy. Two batches of ADSCs were taken, and each batch was divided into normal control group, photodynamic therapy alone group, and photodynamic therapy+rapamycin group, with 3 wells in each group. At culture minute of 15 after the treatment, p-mTOR/mTOR and p-p70 S6K/p70 S6K ratios of cells from the first batch were calculated and detected as before. On culture day of 7 after the treatment, extracellular matrix protein expression of cells from the second batch was detected as before. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: After 12 d of culture, the cells were verified as ADSCs. At culture hour of 24 after the treatment, the ADSC proliferation level ((4.0±1.0)% and (4.1±0.4)%, respectively) and HaCaT cell migration percentages (1.17±0.14 and 1.13±0.12, respectively) in photosensitizer alone group and irradiation alone group were similar to those of normal control group ((3.7±0.6)% and 1.00±0.16, respectively, P>0.05), and were significantly lower than those of photosensitizer+irradiation group ((34.2±7.0)% and 2.55±0.13, respectively, P<0.01). On culture day of 7 after the treatment, compared with those in normal control group, the expression of collagen Ⅲ in ADSCs of photosensitizer alone group was significantly increased (P<0.05), and the expressions of collagen Ⅰ and collagen Ⅲ in ADSCs of irradiation alone group were significantly increased (P<0.01). Compared with those in photosensitizer alone group and irradiation alone group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photosensitizer+irradiation group were significantly increased (P<0.01). Compared with those in 0 min post-photodynamic therapy group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in 15 min post-photodynamic therapy group were significantly increased (P<0.01), the ratios of p-p70 S6K/p70 S6K of ADSCs in 30 min post-photodynamic therapy group and 60 min post-photodynamic therapy group were both significantly increased (P<0.01). At culture minute of 15 after the treatment, compared with those in normal control group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in photodynamic therapy alone group were significantly increased (P<0.05 or P<0.01). Compared with those in photodynamic therapy alone group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in photodynamic therapy+rapamycin group were significantly decreased (P<0.05). On culture day of 7 after the treatment, compared with those in normal control group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photodynamic therapy alone group were significantly increased (P<0.01). Compared with those in photodynamic therapy alone group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photodynamic therapy+rapamycin group were significantly decreased (P<0.01). Conclusions: Low-dose photodynamic therapy can promote the proliferation of ADSCs, improve the ability of ADSCs to regulate the migration of HaCaT cells, and enhance the secretion of extracellular matrix protein by rapidly activating mTOR signaling pathway.
Adipose Tissue
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Female
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Fibronectins
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Humans
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Male
;
Mesenchymal Stem Cells
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Photochemotherapy
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Photosensitizing Agents/pharmacology*
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Sirolimus/pharmacology*
;
TOR Serine-Threonine Kinases
4.Curcumin alleviates the manganese-induced neurotoxicity by promoting autophagy in rat models of manganism.
Li Ye LAI ; Chang Song DOU ; Cui Na ZHI ; Jie CHEN ; Xue MA ; Peng ZHAO ; Bi Yun YAO
Journal of Peking University(Health Sciences) 2022;54(3):400-411
OBJECTIVE:
To investigate the protective effects of curcumin(CUR) and its mechanism on a rat model of neurotoxicity induced by manganese chloride (MnCl2), which mimics mangnism.
METHODS:
Sixty male SD rats were randomly divided into 5 groups, with 12 rats in each group. Control group received 0.9% saline solution intraperitoneally (ip) plus double distilled water (dd) H2O intragastrically (ig), MnCl2 group received 15 mg/kg MnCl2(Mn2+ 6.48 mg/kg) intraperitoneally plus dd H2O intragastrically, CUR group received 0.9% saline solution intraperitoneally plus 300 mg/kg CUR intragastrically, MnCl2+ CUR1 group received 15 mg/kg MnCl2 intraperitoneally plus 100 mg/kg curcumin intragastrically, MnCl2+ CUR2 group received 15 mg/kg MnCl2 intraperitoneally plus 300 mg/kg CUR intragastrically, 5 days/week, 4 weeks. Open-field and rotarod tests were used to detect animals' exploratory behavior, anxiety, depression, movement and balance ability. Morris water maze (MWM) experiment was used to detect animals' learning and memory ability. ICP-MS was used to investigate the Mn contents in striata. The rats per group were perfused in situ, their brains striata were removed by brains model and fixed for transmission electron microscope (TEM), histopathological and immunohistochemistry (ICH) analyses. The other 6 rats per group were sacrificed. Their brains striata were removed and protein expression levels of transcription factor EB (TFEB), mammalian target of rapamycin (mTOR), p-mTOR, Beclin, P62, microtubule-associated protein light chain-3 (LC3) were detected by Western blotting. Terminal deoxynucleotidyl transterase-mediated dUTP nick end labeling (TUNEL) staining was used to determine neurocyte apoptosis of rat striatum.
RESULTS:
After exposure to MnCl2 for four weeks, MnCl2-treated rats showed depressive-like behavior in open-field test, the impairments of movement coordination and balance in rotarod test and the diminishment of spatial learning and memory in MWM (P < 0.05). The striatal TH+ neurocyte significantly decreased, eosinophilic cells, aggregative α-Syn level and TUNEL-positive neurocyte significantly increased in the striatum of MnCl2 group compared with control group (P < 0.05). Chromatin condensation, mitochondria tumefaction and autophagosomes were observed in rat striatal neurocytes of MnCl2 group by TEM. TFEB nuclear translocation and autophagy occurred in the striatum of MnCl2 group. Further, the depressive behavior, movement and balance ability, spatial learning and memory ability of MnCl2+ CUR2 group were significantly improved compared with MnCl2 group (P < 0.05). TH+ neurocyte significantly increased, the eosinophilic cells, aggregative α-Syn level significantly decreased in the striatum of MnCl2+ CUR2 group compared with MnCl2 group. Further, compared with MnCl2 group, chromatin condensation, mitochondria tumefaction was alleviated and autophagosomes increased, TFEB-nuclear translocation, autophagy was enhanced and TUNEL-positive neurocyte reduced significantly in the striatum of MnCl2+ CUR2 group (P < 0.05).
CONCLUSION
Curcumin alleviated the MnCl2-induced neurotoxicity and α-Syn aggregation probably by promoting TFEB nuclear translocation and enhancing autophagy.
Animals
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Autophagy
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Chromatin
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Curcumin/pharmacology*
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Male
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Mammals
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Manganese/toxicity*
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Rats
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Rats, Sprague-Dawley
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Saline Solution/pharmacology*
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TOR Serine-Threonine Kinases
5.Effect and mechanism of Dahuang Zhechong Pills against testicular aging in rats by inhibiting necroptosis signaling pathway.
Huan LI ; Yue TU ; Yi-Gang WAN ; Geng-Lin MU ; Wei WU ; Jia-Xin CHEN ; Mei-Zi WANG ; Jie WANG ; Yan FU ; Yu-Feng CAI ; Yu WANG ; Zi-Yue WAN
China Journal of Chinese Materia Medica 2022;47(15):4119-4127
To explore the effect and mechanism of Dahuang Zhechong Pills(DHZCP), a classical prescription, in improving testicular aging(TA) in vivo, the authors randomly divided 24 male rats into four groups: the normal, model, DHZCP and vitamin E(VE) groups. The TA rat model was established by continuous gavage of D-galactose(D-gal). During the experiment, the rats in the DHZCP and VE groups were given DHZCP suspension and VE suspension, respectively by gavage, while those in the normal and model groups were gavaged saline separately every day. After the co-administration of D-gal and various drugs for 60 days, all rats were sacrificed, and their blood and testis were collected. Further, various indexes related to TA and necroptosis of testicular cells in the model rats were examined and investigated, which included the aging phenotype, total testicular weight, testicular index, histopathological features of testis, number of spermatogenic cells, sex hormone level, expression characteristics of reactive oxygen species(ROS) in testis, expression levels and characteristics of cyclins in testis, and protein expression levels of the key molecules in receptor-interacting serine/threonine-protein kinase 1(RIPK1)/receptor-interacting serine/threonine-protein kinase 3(RIPK3)/mixed lineage kinase domain like pseudokinase(MLKL) signaling pathway in each group. The results showed that, for the TA model rats, both DHZCP and VE improved their aging phenotype, total testicular weight, testicular index, pathological features of testis, number of spermatogenic cells, serum testosterone and follicle stimulating hormone levels, expression characteristics of ROS and protein expression levels and characteristics of P21 and P53 in testis. In addition, DHZCP and VE improved the protein expression levels of the key molecules in RIPK1/RIPK3/MLKL signaling pathway in testis of the model rats. Specifically, DHZCP was better than VE in the improvement of RIPK3. In conclusion, in this study, the authors found that DHZCP, similar to VE, ameliorated D-gal-induced TA in model rats in vivo, and its mechanism was related to reducing necroptosis of testicular cells by inhibiting the activation of RIPK1/RIPK3/MLKL signaling pathway. This study provided preliminary pharmacological evidence for the development and application of classical prescriptions in the field of men's health.
Aging
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Animals
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Drugs, Chinese Herbal
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Male
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Necroptosis
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Protein Kinases/genetics*
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Rats
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Reactive Oxygen Species/metabolism*
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Receptor-Interacting Protein Serine-Threonine Kinases/pharmacology*
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Serine/pharmacology*
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Signal Transduction
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Testis
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Threonine/pharmacology*
6.Effects and mechanisms of total flavones of Abelmoschus manihot in inhibiting podocyte necroptosis and renal fibrosis in diabetic kidney disease.
Jia-Xin CHEN ; Qi-Jun FANG ; Yi-Gang WAN ; Ying-Lu LIU ; Yu WANG ; Wei WU ; Yue TU ; Mei-Zi WANG ; Dian-Guang WANG ; Hai-Tao GE
China Journal of Chinese Materia Medica 2023;48(15):4137-4146
Previous studies have shown that high blood glucose-induced chronic microinflammation can cause inflammatory podocyte injury in patients with diabetic kidney disease(DKD). Therein, necroptosis is a new form of podocyte death that is closely associated with renal fibrosis(RF). To explore the effects and mechanisms in vivo of total flavones of Abelmoschus manihot(TFA), an extract from traditional Chinese herbal medicine Abelmoschus manihot for treating kidney diseases, on podocyte necroptosis and RF in DKD, and to further reveal its scientific connotation with multi-pathway and multi-target, the authors randomly divided all rats into four groups: a namely normal group, a model group, a TFA group and a rapamycin(RAP) group. After the modified DKD rat models were successfully established, four group rats were given double-distilled water, TFA suspension and RAP suspension, respectively by gavage every day. At the end of the 4th week of drug treatment, all rats were sacrificed, and the samples of their urine, blood and kidneys were collected. And then, the various indicators related to podocyte necroptosis and RF in the DKD model rats were observed, detected and analyzed, respectively. The results indicated that, general condition, body weight(BW), serum creatinine(Scr), urinary albumin(UAlb), and kidney hypertrophy index(KHI) in these modified DKD model rats were both improved by TFA and RAP. Indicators of RF, including glomerular histomorphological characteristics, fibronectin(FN) and collagen type Ⅰ(collagen Ⅰ) staining extent in glomeruli, as well as the protein expression levels of FN, collagen Ⅰ, transforming growth factor-β1(TGF-β1) and Smad2/3 in the kidneys were improved respectively by TFA and RAP. Podocyte damage, including foot process form and the protein expression levels of podocin and CD2AP in the kidneys was improved by TFA and RAP. In addition, tumor necrosis factor-α(TNF-α)-mediated podocyte necroptosis in the kidneys, including the morphological characteristics of podocyte necroptosis, the extent and levels of the protein expression of TNF-α and phosphorylated mixed lineage kinase domain like pseudokinase(p-MLKL) was improved respectively by TFA and RAP. Among them, RAP had the better effect on p-MLKL. More importantly, the activation of the receptor interacting serine/threonine protein kinase 1(RIPK1)/RIPK3/MLKL signaling axis in the kidneys, including the expression levels of its key signaling molecules, such as phosphorylated receptor interacting serine/threonine protein kinase 1(p-RIPK1), p-RIPK3, p-MLKL and cysteinyl aspartate specific proteinase-8(caspase-8) was improved respectively by TFA and RAP. Among them, the effect of TFA on p-RIPK1 was superior. On the whole, in this study, the authors demonstrated that TFA alleviates podocyte necroptosis and RF in DKD through inhibiting the activation of the TNF-α-mediated RIPK1/RIPK3/MLKL signaling axis in diabetic kidneys. The authors' findings provide new pharmacological evidence to reveal the scientific connotation of TFA in treating RF in DKD in more depth.
Humans
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Rats
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Animals
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Diabetic Nephropathies/drug therapy*
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Abelmoschus
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Flavones/pharmacology*
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Podocytes
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Tumor Necrosis Factor-alpha/metabolism*
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Necroptosis
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Receptor-Interacting Protein Serine-Threonine Kinases/metabolism*
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Fibrosis
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Threonine/pharmacology*
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Collagen/metabolism*
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Serine/pharmacology*
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Diabetes Mellitus/drug therapy*
7.Effects of insulin and LY294002 inhibitors of PI3K on the regulations and expression of aquaporin 9 in normal liver cells.
Hui LIU ; Zhe-Chuan MEI ; Xiao XIAO
Chinese Journal of Hepatology 2010;18(6):455-458
OBJECTIVESTo explore the effects of insulin on the expression and the regulatory pathway of AQP9 in normal human liver cells.
METHODSNormal human liver cells L02 were cultured and treated with PI3K inhibitor LY294002, AKT inhibitor A-443654, MAPK inhibitors SB2030580 and insulin at different concentrations respectively. The AQP9 mRNA and protein expressions were detected with semi-quantitative RT-PCR and Western blot respectively.
RESULTSThe insulin (100 nmol/L approximately 500 nmol/L) treatment decreased the expression of AQP9 in normal human liver cells (P less than 0.05) concentration dependently, and the expression of AQP9 began to reduce from 3 hours of insulin stimulation (P less than 0.05), especially at insulin treatment for 12 hours (P less than 0.05); Incubated with the selective inhibitor of PI3K (LY294002) and AKT (A-443654), the inhibitory effects of insulin on AQP9 expression decreased (P less than 0.05); but it did not change significantly by blocking the MAPK signaling pathway.
CONCLUSIONThe insulin treatment inhibited the expression of AQP9 and the PI3K/akt signal transduction pathway was involved in the mechanism.
Aquaporins ; metabolism ; Cells, Cultured ; Chromones ; pharmacology ; Hepatocytes ; drug effects ; metabolism ; Humans ; Insulin ; pharmacology ; Morpholines ; pharmacology ; Phosphatidylinositol 3-Kinase ; antagonists & inhibitors ; metabolism ; Protein-Serine-Threonine Kinases ; metabolism ; Signal Transduction
8.Inhibitory effect and kinetic analysis of sodium quercetin-7,4'-disulphate on recombinant human protein kinase CK2 holoenzyme.
Xin-guang LIU ; Nian-ci LIANG ; Wen LIU ; Ji SHE ; Li-er MO
Acta Pharmaceutica Sinica 2002;37(3):165-168
AIMTo study the direct effect and kinetics of sodium quercetin-7,4'-disulphate (SQDS) on recombinant human protein kinase CK2 holoenzyme.
METHODSThe recombinant human CK2 holoenzyme activity was assayed by detecting incorporation of 32P of [gamma-32P] ATP into the substrate in various conditions.
RESULTSThe recombinant human CK2 was a second messenger (Ca2+, cAMP and cGMP) independent protein kinase. The characterization and function of the reconstituted holoenzyme were consistent with those of native CK2. SQDS was shown to strongly inhibit the holoenzyme activity of recombinant human protein kinase CK2 with an IC50 of 4.4 mumol.L-1, which was more effective than DRB and A3, known CK2 special inhibitors. Kinetic studies of SQDS on recombinant human CK2 showed: the inhibition was competitive with ATP and noncompetitive with casein.
CONCLUSIONSQDS is a potent inhibitor of protein kinase CK2. This study provide experimental basis for the development of more effective inhibitors of CK2 and for clinical application of SQDS in the future.
Casein Kinase II ; Dichlororibofuranosylbenzimidazole ; pharmacology ; Enzyme Inhibitors ; pharmacology ; Humans ; Kinetics ; Protein-Serine-Threonine Kinases ; antagonists & inhibitors ; metabolism ; Quercetin ; analogs & derivatives ; pharmacology ; Recombinant Proteins ; antagonists & inhibitors ; metabolism
9.IRE1α deficiency impairs autophagy in chondrocytes by upregulating calcium homeostasis endoplasmic reticulum protein.
Xing Yue LI ; Dan Yang YIN ; Meng Tian FAN ; Yu You YANG ; Li LIANG ; Nai Bo FENG ; Xiao Li LI ; Feng Jin GUO
Journal of Southern Medical University 2022;42(6):785-793
OBJECTIVE:
To explore the mechanism by which inositol-requiring enzyme-1α (IRE1α) regulates autophagy function of chondrocytes through calcium homeostasis endoplasmic reticulum protein (CHERP).
METHODS:
Cultured human chondrocytes (C28/I2 cells) were treated with tunicamycin, 4μ8c, rapamycin, or both 4μ8c and rapamycin, and the expressions of endoplasmic reticulum (ER) stress- and autophagy-related proteins were detected with Western blotting. Primary chondrocytes from ERN1 knockout (ERN1 CKO) mice and wild-type mice were examined for ATG5 and ATG7 mRNA expressions, IRE1α and p-IRE1α protein expressions, and intracellular calcium ion content using qPCR, Western blotting and flow cytometry. The effect of bafilomycin A1 treatment on LC3 Ⅱ/LC3 Ⅰ ratio in the isolated chondrocytes was assessed with Western blotting. Changes in autophagic flux of the chondrocytes in response to rapamycin treatment were detected using autophagy dual fluorescent virus. The changes in autophagy level in C28/I2 cells overexpressing CHERP and IRE1α were detected using immunofluorescence assay.
RESULTS:
Tunicamycin treatment significantly up-regulated ER stress-related proteins and LC3 Ⅱ/LC3 Ⅰ ratio and down-regulated the expression of p62 in C28/I2 cells (P < 0.05). Rapamycin obviously up-regulated LC3 Ⅱ/LC3 Ⅰ ratio (P < 0.001) in C28/I2 cells, but this effect was significantly attenuated by co-treatment with 4μ8c (P < 0.05). Compared with the cells from the wild-type mice, the primary chondrocytes from ERN1 knockout mice showed significantly down-regulated mRNA levels of ERN1 (P < 0.01), ATG5 (P < 0.001) and ATG7 (P < 0.001), lowered or even lost expressions of IRE1α and p-IRE1α proteins (PP < 0.01), and increased expression of CHERP (P < 0.05) and intracellular calcium ion content (P < 0.001). Bafilomycin A1 treatment obviously increased LC3 Ⅱ/ LC3 Ⅰ ratio in the chondrocytes from both wild-type and ERN1 knockout mice (P < 0.01 or 0.05), but the increment was more obvious in the wild-type chondrocytes (P < 0.05). Treatment with autophagy dual-fluorescence virus resulted in a significantly greater fluorescence intensity of LC3-GFP in rapamycin-treated ERN1 CKO chondrocytes than in wild-type chondrocytes (P < 0.05). In C28/I2 cells, overexpression of CHERP obviously decreased the fluorescence intensity of LC3, and overexpression of IRE1α enhanced the fluorescence intensity and partially rescued the fluorescence reduction of LC3 caused by CHERP.
CONCLUSION
IRE1α deficiency impairs autophagy in chondrocytes by upregulating CHERP and increasing intracellular calcium ion content.
Animals
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Autophagy
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Calcium/metabolism*
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Chondrocytes
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Endoplasmic Reticulum/metabolism*
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Endoribonucleases/pharmacology*
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Homeostasis
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Inositol
;
Mice
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Mice, Knockout
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Protein Serine-Threonine Kinases
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RNA, Messenger/metabolism*
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Sirolimus/pharmacology*
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Tunicamycin/pharmacology*
10.Romidepsin (FK228) improves the survival of allogeneic skin grafts through downregulating the production of donor-specific antibody via suppressing the IRE1α-XBP1 pathway.
Yuliang GUO ; Siyu SONG ; Xiaoxiao DU ; Li TIAN ; Man ZHANG ; Hongmin ZHOU ; Zhonghua Klaus CHEN ; Sheng CHANG
Journal of Zhejiang University. Science. B 2022;23(5):392-406
Antibody-mediated rejection (AMR) is one of the major causes of graft loss after transplantation. Recently, the regulation of B cell differentiation and the prevention of donor-specific antibody (DSA) production have gained increased attention in transplant research. Herein, we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin (FK228) on DSA. The survival of grafted skins was monitored daily. The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry. Then, we isolated and purified B cells from B6 mouse spleens in vitro by magnetic bead sorting. The B cells were cultured with interleukin-4 (IL-4) and anti-clusters of differentiation 40 (CD40) antibody with or without FK228 treatment. The immunoglobulin G1 (IgG1) and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay (ELISA). Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting were conducted to determine the corresponding levels of messenger RNA (mRNA) and protein expression in cultured cells and the recipient spleens. The results showed that FK228 significantly improved the survival of allogeneic skin grafts. Moreover, FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1 (HADC1) and HDAC2 and the upregulation of the acetylation of histones H2A and H3. It also inhibited the differentiation of B cells to plasma cells, decreased the transcription of positive regulatory domain-containing 1 (Prdm1) and X-box-binding protein 1 (Xbp1), and decreased the expression of phosphorylated inositol-requiring enzyme 1 α (p-IRE1α), XBP1, and B lymphocyte-induced maturation protein-1 (Blimp-1). In conclusion, FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway. Thus, FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.
Animals
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Depsipeptides
;
Endoribonucleases
;
Hematopoietic Stem Cell Transplantation
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Histone Deacetylase Inhibitors/pharmacology*
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Mice
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Protein Serine-Threonine Kinases
;
Skin Transplantation