Levels of base excision repair proteins in CD4+ T cells in patients with systemic lupus erythematosus / 中南大学学报(医学版)

OBJECTIVES@#Systemic lupus erythematosus (SLE) is a multi-systemic disease with the unknown pathogenic mechanism. DNA demethylation is involved in SLE pathogenesis. Growth arrest and DNA damage inducible 45 alpha (Gadd45a) takes part in the process of DNA demethylation. Gadd45a is a DNA repair-related protein. This study aims to investigate the expressions of some proteins [including activation-induced cytidine deaminase (AID), thymine DNA glycosylase (TDG), and methyl-CpG-binding domain protein 4 (MBD4)] involving in base excision repair (BER) process in CD4+ T cells in patients with SLE, and to analyze the correlations between the above BER proteins and lupus disease.@*METHODS@#From January 2019 to September 2020, 12 SLE patients and 12 healthy controls were recruited from Second Xiangya Hospital of Central South University. Peripheral blood mononuclear cells (PBMCs) were separated by Ficoll-Hypaque density gradient centrifugation and then CD4+ T cells were isolated via positive selection using Miltenyi beads. We measured the messenger RNA (mRNA) and protein expressions of AID, TDG, and MBD4 by real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blotting, respectively.@*RESULTS@#In contrast to controls, in SLE CD4+ T cells, the mRNA and protein expressions of AID were elevated (P=0.003, P=0.022, respectively); TDG protein expression was increased (P=0.017); and MBD4 protein level was reduced (P<0.001). No visible distinctions was found in the mRNA expressions of either TDG or MBD4 between the 2 groups (both P>0.05). The mRNA and protein expressions of AID and the protein levels of TDG were positively correlated with SLE disease activity index (SLEDAI). And the mRNA and protein expressions of MBD4 were negatively correlated with SLEDAI.@*CONCLUSIONS@#In SLE CD4+ T cells, the increased expressions of AID and TDG and the decreased MBD4 expression may participate in SLE pathogenic mechanism.

Effect of Toll-like Receptor 4 on Cerebral Ischemia Reperfusion Injury in Rats / 中国医科大学学报

Objective To explore the effect and mechanism of Toll-like receptor 4 (TLR4) on cerebral ischemia/reperfusion injury. Methods Rats were divided into a sham group, MCAO group, and MCAO+TAK group. Cerebral cortices were removed on day 1, 3, 7, and 14 post surgery. Morphological staining and Western blotting were used to detect pathological changes and TLR4 and P-IKKα/β expression in brain tissues. Results The pathological changes in the MCAO+TAK group were more severe than in the MCAO group on day 1 post surgery. However, the MCAO group exhibited more severe damage at the other time points. TLR4 expression was lowest in the cerebral cortices of the sham group. On day 1 and 14 post surgery, TLR4 expression was lower in the MCAO group than in the MCAO+TAK group, while on day 3 and 7 post surgery, TLR4 expression was higher in the MCAO group than in the MCAO+TAK group. P-IKKα/β expression was highest in the cerebral cortices of the MCAO group at all time points except for day 1. Conclusion TLR4 may alleviate cerebral ischemia reperfusion injury in rats on day 1 post surgery; however, TLR4 may exacerbate ischemia repeifusion injury 3 to 14 days post surgery. The mechanism may be due to the effect of P-IKKα/β expression in the cerebral cortex.

Application of phase angle in estimating malnutrition and clinical practice / 中华临床营养杂志

Phase angle (PA), derived by bioelectrical impedance analysis, has been used to evaluate nutritional status.It has a unique advantage in diagnosing early malnutrition related to diseases by the detection of human body cell membrane integrity and fluid composition change, and being associated with bad disease prognosis in part of clinical research.Because of its non-invasive, convenient, accurate and affordable technique, it has a wide prospect of clinical application.However, lack of uniform PA reference value somehow limited its application.We summarize the latest clinical research and application situation of PA, and explore the characteristics and the influence factors of PA in different disease group, in order to provide theoretical basis for the Chinese PA reference range.