The heterotrimeric guanine nucleotide-binding protein （G-protein） has been demonstrated to mediate various signaling pathways in plants. However, its role in phytochrome A （phyA） signaling remains elusive. In this...The heterotrimeric guanine nucleotide-binding protein （G-protein） has been demonstrated to mediate various signaling pathways in plants. However, its role in phytochrome A （phyA） signaling remains elusive. In this study, we discover a new phyA-mediated phenotype designated far-red irradiation （FR） preconditioned cell death, which occurs only in the hypocotyls of FR-grown seedlings following exposure to white light （WL）. The cell death is mitigated in the Gα mutant gpal but aggravated in the Gβ mutant agbl in comparison with the wild type （WT）, indicative of antagonistic roles of GPA1 and AGBI in the phyA-mediated cell-death pathway. Further investigation indicates that FR-induced accumulation of nonphotoconvertible protochlorophyllide （Pchlide^633）, which generates reactive oxygen species （ROS） on exposure to WL, is required for FR-preconditioned cell death. Moreover, ROS is mainly detected in chloroplasts using the fluorescent probe. Interestingly, the application of H2O2 to dark-grown seedlings results in a phenotype similar to FR-preconditioned cell death. This reveals that ROS is a critical mediator for the ceil death. In addition, we observe that agb1 is more sensitive to H2O2 than WT seedlings, indicating that the G-protein may also modify the sensitivity of the seedlings to ROS stress. Taking these results together, we infer that the G-protein may be involved in the phyA signaling pathway to regulate FR-preconditioned cell death ofArabidopsis hypocotyls. A possible mechanism underlying the involvement of the G-protein in phyA signaling is discussed in this study.展开更多
目的:探讨特异性激活G蛋白偶联雌激素受体(GPER)对结直肠癌(CRC)细胞迁移的作用及其可能的机制。方法:体外培养CRC细胞RKO和SW480,使用0.5或1.0μmol/L的GPER特异性激活剂(G-1)处理CRC细胞,采用CCK-8法、划痕实验和Transwell实验分别检...目的:探讨特异性激活G蛋白偶联雌激素受体(GPER)对结直肠癌(CRC)细胞迁移的作用及其可能的机制。方法:体外培养CRC细胞RKO和SW480,使用0.5或1.0μmol/L的GPER特异性激活剂(G-1)处理CRC细胞,采用CCK-8法、划痕实验和Transwell实验分别检测G-1对CRC细胞增殖、迁移的影响。用q PCR和WB法分别检测G-1及G-1+活性氧(ROS)清除剂N-乙酰半胱氨酸(NAC)处理对RKO细胞E-钙黏素(E-Cad)、纤连蛋白(FN)m RNA和蛋白表达的影响,用流式细胞术检测RKO细胞中ROS的水平。结果:经G-1处理后RKO和SW480细胞的迁移能力均明显减弱(均P<0.05),能显著上调细胞中E-cad m RNA及蛋白表达、下调FN m RNA及蛋白表达(均P<0.05)。G-1处理能刺激RKO细胞ROS水平上升,在NAC的作用下,由G-1引起的E-cad、FN蛋白表达变化被部分逆转。结论:特异性激活GPER通过上调ROS水平抑制EMT进程,进而抑制CRC细胞的迁移。展开更多
Background: The new 5G telecommunication technology has stirred concerns about potential negative effects on human health by radiofrequency electromagnetic fields. As to whether skin biology can be affected by 5G wave...Background: The new 5G telecommunication technology has stirred concerns about potential negative effects on human health by radiofrequency electromagnetic fields. As to whether skin biology can be affected by 5G waves has remained an unsolved challenge despite recent studies dealing with this issue. In particular, a strategy for rational design of an assay allowing to 1) reproducibly evaluate and decipher the 5G effects on skin as well as 2) test the potential protective effects of cosmetic active ingredients, has yet to be found. Here we describe an in vitro model of human normal keratinocytes irradiated by 5G waves and show their impact on two biomarkers of inflammatory stress, i.e. interleukin-1β (IL-1β) and reactive oxygen species (ROS) production. In addition, the capacity of a tannin-rich plant extract to protect against 5G impact is evaluated. Materials and Methods: In the first series of experiments, monolayers of human normal keratinocytes were irradiated or not (control) by 5G waves (3.5 MHz) in an anechoic chamber and were incubated at 37˚C for 24 hours. At the end of the incubation period, extracellular IL-1β and intracellular ROS were quantified using specific ELISA and colorimetric assays, respectively. In the second series of experiments, the effect of an overnight pre-incubation with increasing concentrations of a tannin-rich plant extract was evaluated. Additionally, we studied in a prospective way the expression of a set of 88 genes selected for their relevance to keratinocyte homeostasis, in relation to the 5G challenge as well as the protective effect of a tannin-rich plant extract. Results: 5G waves significantly increased IL-1β production by 48.4% (p β and ROS production. Finally, the expression of 47 genes was modified by 5G waves and/or by the tannin-rich plant extract. Conclusion: This is to our knowledge the first evaluation of the impact of 5G technology on inflammatory biomarkers of human normal skin cells. Here we provide an innovative and pertinent tool to screen for natural compounds with protective effects against 5G waves to develop cosmetic products shielding against the potentially deleterious effects of electromagnetic waves on human skin.展开更多
Background: The neutrophils (PMN) are our main blood cells to combat fungi, bacteria, and fibrin. For normal function, an activated PMN generates a certain concentration of reactive oxygen species (ROS). If the genera...Background: The neutrophils (PMN) are our main blood cells to combat fungi, bacteria, and fibrin. For normal function, an activated PMN generates a certain concentration of reactive oxygen species (ROS). If the generated blood ROS concentration is too low, then fungi, bacteria or fibrin might threaten the life of the patient, and it could be of great medical interest to stimulate PMN by physiologic drugs. Granulocyte-Colony Stimulating Factor (G-CSF) is a cell hormone that increases the cell number of PMN and that stimulates the individual PMN. The blood ROS generation assay (BRGA) is an innovative physiologic test to monitor the ROS generation of PMN in blood. Here the ROS generating action of G-CSF on normal PMN is quantified. Material and Methods: 40 μl 0 - 10.3 ng/ml (final conc.) G-CSF (in 5% human albumin) in black Brand? 781608 high quality polystyrene F-microwells was incubated in triplicate with 125 μl Hanks’ balanced salt solution (HBSS;modified without phenol red) and 10 μl normal citrated blood. Immediately (BRGA) or after 60 min (BRGA-60-) 10 μl 5 mM luminol sodium salt in 0.9% NaCl and 10 μl 0 or 36 μg/ml zymosan A in 0.9% NaCl was added. The photons were counted within 0 - 318 min (37°C) in a photons-multiplying microtiter plate luminometer. At about 0.5 t-maxn (0.5 fold the time to normal maximum) the approx. SC200 of G-CSF was determined. Results and Discussion: The approx. SC200 of G-CSF on normal blood ROS generation was 0.2 μg/l (=20 IU/ml). In clinical situations where an increased blood ROS generation is pharmacologically required, few micrograms of G-CSF could be a sufficient dosage for an adult patient. The BRGA helps to find out the correct stimulating G-CSF dosage for each individual. An enhanced PMN function could favor a better clinical outcome in situations of wanted increase of the innate immunology or in cellular fibrinolysis. G-CSF plasma concentrations of 0.1 - 1 μg/l might favor singlet oxygen generation without immunosuppression or cell fragment-induced thrombin generation.展开更多
文摘The heterotrimeric guanine nucleotide-binding protein （G-protein） has been demonstrated to mediate various signaling pathways in plants. However, its role in phytochrome A （phyA） signaling remains elusive. In this study, we discover a new phyA-mediated phenotype designated far-red irradiation （FR） preconditioned cell death, which occurs only in the hypocotyls of FR-grown seedlings following exposure to white light （WL）. The cell death is mitigated in the Gα mutant gpal but aggravated in the Gβ mutant agbl in comparison with the wild type （WT）, indicative of antagonistic roles of GPA1 and AGBI in the phyA-mediated cell-death pathway. Further investigation indicates that FR-induced accumulation of nonphotoconvertible protochlorophyllide （Pchlide^633）, which generates reactive oxygen species （ROS） on exposure to WL, is required for FR-preconditioned cell death. Moreover, ROS is mainly detected in chloroplasts using the fluorescent probe. Interestingly, the application of H2O2 to dark-grown seedlings results in a phenotype similar to FR-preconditioned cell death. This reveals that ROS is a critical mediator for the ceil death. In addition, we observe that agb1 is more sensitive to H2O2 than WT seedlings, indicating that the G-protein may also modify the sensitivity of the seedlings to ROS stress. Taking these results together, we infer that the G-protein may be involved in the phyA signaling pathway to regulate FR-preconditioned cell death ofArabidopsis hypocotyls. A possible mechanism underlying the involvement of the G-protein in phyA signaling is discussed in this study.
文摘目的:探讨特异性激活G蛋白偶联雌激素受体(GPER)对结直肠癌(CRC)细胞迁移的作用及其可能的机制。方法:体外培养CRC细胞RKO和SW480,使用0.5或1.0μmol/L的GPER特异性激活剂(G-1)处理CRC细胞,采用CCK-8法、划痕实验和Transwell实验分别检测G-1对CRC细胞增殖、迁移的影响。用q PCR和WB法分别检测G-1及G-1+活性氧(ROS)清除剂N-乙酰半胱氨酸(NAC)处理对RKO细胞E-钙黏素(E-Cad)、纤连蛋白(FN)m RNA和蛋白表达的影响,用流式细胞术检测RKO细胞中ROS的水平。结果:经G-1处理后RKO和SW480细胞的迁移能力均明显减弱(均P<0.05),能显著上调细胞中E-cad m RNA及蛋白表达、下调FN m RNA及蛋白表达(均P<0.05)。G-1处理能刺激RKO细胞ROS水平上升,在NAC的作用下,由G-1引起的E-cad、FN蛋白表达变化被部分逆转。结论:特异性激活GPER通过上调ROS水平抑制EMT进程,进而抑制CRC细胞的迁移。
文摘Background: The new 5G telecommunication technology has stirred concerns about potential negative effects on human health by radiofrequency electromagnetic fields. As to whether skin biology can be affected by 5G waves has remained an unsolved challenge despite recent studies dealing with this issue. In particular, a strategy for rational design of an assay allowing to 1) reproducibly evaluate and decipher the 5G effects on skin as well as 2) test the potential protective effects of cosmetic active ingredients, has yet to be found. Here we describe an in vitro model of human normal keratinocytes irradiated by 5G waves and show their impact on two biomarkers of inflammatory stress, i.e. interleukin-1β (IL-1β) and reactive oxygen species (ROS) production. In addition, the capacity of a tannin-rich plant extract to protect against 5G impact is evaluated. Materials and Methods: In the first series of experiments, monolayers of human normal keratinocytes were irradiated or not (control) by 5G waves (3.5 MHz) in an anechoic chamber and were incubated at 37˚C for 24 hours. At the end of the incubation period, extracellular IL-1β and intracellular ROS were quantified using specific ELISA and colorimetric assays, respectively. In the second series of experiments, the effect of an overnight pre-incubation with increasing concentrations of a tannin-rich plant extract was evaluated. Additionally, we studied in a prospective way the expression of a set of 88 genes selected for their relevance to keratinocyte homeostasis, in relation to the 5G challenge as well as the protective effect of a tannin-rich plant extract. Results: 5G waves significantly increased IL-1β production by 48.4% (p β and ROS production. Finally, the expression of 47 genes was modified by 5G waves and/or by the tannin-rich plant extract. Conclusion: This is to our knowledge the first evaluation of the impact of 5G technology on inflammatory biomarkers of human normal skin cells. Here we provide an innovative and pertinent tool to screen for natural compounds with protective effects against 5G waves to develop cosmetic products shielding against the potentially deleterious effects of electromagnetic waves on human skin.
文摘Background: The neutrophils (PMN) are our main blood cells to combat fungi, bacteria, and fibrin. For normal function, an activated PMN generates a certain concentration of reactive oxygen species (ROS). If the generated blood ROS concentration is too low, then fungi, bacteria or fibrin might threaten the life of the patient, and it could be of great medical interest to stimulate PMN by physiologic drugs. Granulocyte-Colony Stimulating Factor (G-CSF) is a cell hormone that increases the cell number of PMN and that stimulates the individual PMN. The blood ROS generation assay (BRGA) is an innovative physiologic test to monitor the ROS generation of PMN in blood. Here the ROS generating action of G-CSF on normal PMN is quantified. Material and Methods: 40 μl 0 - 10.3 ng/ml (final conc.) G-CSF (in 5% human albumin) in black Brand? 781608 high quality polystyrene F-microwells was incubated in triplicate with 125 μl Hanks’ balanced salt solution (HBSS;modified without phenol red) and 10 μl normal citrated blood. Immediately (BRGA) or after 60 min (BRGA-60-) 10 μl 5 mM luminol sodium salt in 0.9% NaCl and 10 μl 0 or 36 μg/ml zymosan A in 0.9% NaCl was added. The photons were counted within 0 - 318 min (37°C) in a photons-multiplying microtiter plate luminometer. At about 0.5 t-maxn (0.5 fold the time to normal maximum) the approx. SC200 of G-CSF was determined. Results and Discussion: The approx. SC200 of G-CSF on normal blood ROS generation was 0.2 μg/l (=20 IU/ml). In clinical situations where an increased blood ROS generation is pharmacologically required, few micrograms of G-CSF could be a sufficient dosage for an adult patient. The BRGA helps to find out the correct stimulating G-CSF dosage for each individual. An enhanced PMN function could favor a better clinical outcome in situations of wanted increase of the innate immunology or in cellular fibrinolysis. G-CSF plasma concentrations of 0.1 - 1 μg/l might favor singlet oxygen generation without immunosuppression or cell fragment-induced thrombin generation.
