Heat stress can stimulate an increase in body temperature, which is correlated with increased expression of heat shock protein 70 （HSP70） and tumor necrosis factor a （TNFa）. The exact mechanism underlying the HSP7...Heat stress can stimulate an increase in body temperature, which is correlated with increased expression of heat shock protein 70 （HSP70） and tumor necrosis factor a （TNFa）. The exact mechanism underlying the HSP70 and TNFa induction is unclear. Berberine （BBR） can significantly inhibit the temperature rise caused by heat stress, but the mechanism responsible for the BBR effect on HSP70 and TNFa signaling has not been investigated. The aim of the present study was to explore the relationship between the expression of HSP70 and TNFa and the effects of BBR under heat conditions, using in vivo and in vitro models. The expression levels of HSP70 and YNFa were determined using RT-PCR and Western blotting analyses. The results showed that the levels of HSP70 and TNFa were ap-regulated under heat conditions （40 ~C）. HSP70 acted as a chaperone to maintain TNFa homeostasis with rising the temperature, but knockdown of HSP70 could not down-regulate the level of TNFa. Furthermore, TNFa could not influence the expression of HSP70 under aormal and heat conditions. BBR targeted both HSP70 and TNFa by suppressing their gene transcription, thereby decreasing body temperature under heat conditions. In conclusion, BBR has a potential to be developed as a therapeutic strategy for suppressing the thermal effects in hot environments.展开更多
We in vitro examined the existing prognoses of the dissociation constant, KD, between ТАТА- Binding Protein (TBP) and ТАТА box with single nucleotide polymorphism (SNP) associated with human diseases. Five SNP...We in vitro examined the existing prognoses of the dissociation constant, KD, between ТАТА- Binding Protein (TBP) and ТАТА box with single nucleotide polymorphism (SNP) associated with human diseases. Five SNPs of the genes for cytochrome P450 2A6 (associated with lung cancer), β-globin (associated with β-thalassemia), mannose binding lectin (associated with variable immunodeficiency), superoxide dismutase 1 (associated with amyotrophic lateral sclerosis) and triosephosphate isomerase (associated with anemia) fell within the range of –ln(KD;M/KD;WT) between –1.5 and –1 (here KD;WT and KD;M denote the normal ТАТА box and with SNP). The mea-surements using EMSA demonstrated that: 1) all the predictions stating that the affinity between ТВР and ТАТА boxes with SNPs would be reduced were correct;2) the departures of three predictions from the measurements fell within the confidence interval;3) all the predictions consistently underestimated actual mutational damage caused to ТАТА boxes with SNPs (a < 0.05;binomial law) and two of these predictions did so significantly (a < 0.05, Student’s t-test). This consistent underestimation seems to be associated with the damage to the context that modulates ТВP/ТАТА affinity, for example, the contact between the nucleosomal histone H3-Н4 dimer and the core promoter immediately near ТАТА boxes.展开更多
基金supported by the National Natural Science Foundation of China(Nos.81374006,90713043 and 81073092)
文摘Heat stress can stimulate an increase in body temperature, which is correlated with increased expression of heat shock protein 70 （HSP70） and tumor necrosis factor a （TNFa）. The exact mechanism underlying the HSP70 and TNFa induction is unclear. Berberine （BBR） can significantly inhibit the temperature rise caused by heat stress, but the mechanism responsible for the BBR effect on HSP70 and TNFa signaling has not been investigated. The aim of the present study was to explore the relationship between the expression of HSP70 and TNFa and the effects of BBR under heat conditions, using in vivo and in vitro models. The expression levels of HSP70 and YNFa were determined using RT-PCR and Western blotting analyses. The results showed that the levels of HSP70 and TNFa were ap-regulated under heat conditions （40 ~C）. HSP70 acted as a chaperone to maintain TNFa homeostasis with rising the temperature, but knockdown of HSP70 could not down-regulate the level of TNFa. Furthermore, TNFa could not influence the expression of HSP70 under aormal and heat conditions. BBR targeted both HSP70 and TNFa by suppressing their gene transcription, thereby decreasing body temperature under heat conditions. In conclusion, BBR has a potential to be developed as a therapeutic strategy for suppressing the thermal effects in hot environments.
文摘We in vitro examined the existing prognoses of the dissociation constant, KD, between ТАТА- Binding Protein (TBP) and ТАТА box with single nucleotide polymorphism (SNP) associated with human diseases. Five SNPs of the genes for cytochrome P450 2A6 (associated with lung cancer), β-globin (associated with β-thalassemia), mannose binding lectin (associated with variable immunodeficiency), superoxide dismutase 1 (associated with amyotrophic lateral sclerosis) and triosephosphate isomerase (associated with anemia) fell within the range of –ln(KD;M/KD;WT) between –1.5 and –1 (here KD;WT and KD;M denote the normal ТАТА box and with SNP). The mea-surements using EMSA demonstrated that: 1) all the predictions stating that the affinity between ТВР and ТАТА boxes with SNPs would be reduced were correct;2) the departures of three predictions from the measurements fell within the confidence interval;3) all the predictions consistently underestimated actual mutational damage caused to ТАТА boxes with SNPs (a < 0.05;binomial law) and two of these predictions did so significantly (a < 0.05, Student’s t-test). This consistent underestimation seems to be associated with the damage to the context that modulates ТВP/ТАТА affinity, for example, the contact between the nucleosomal histone H3-Н4 dimer and the core promoter immediately near ТАТА boxes.
