Electro-nape-acupuncture regulates the differentiation of microglia through PD-1/PD-L1 reducing secondary brain injury in acute phase intracerebral hemorrhage rats.

INTRODUCTION: This study aimed to investigate the effect of electro-nape-acupuncture (ENA) on the differentiation of microglia and the secondary brain injury in rats with acute-phase intracerebral hemorrhage (ICH) through the programmed cell death protein-1/ligand-1 (PD-1/PD-L1) pathway. METHODS: A total of 27 male Sprague-Dawley rats were randomly divided into three groups: sham group, ICH group, and ENA group. The autologous blood infusion intracerebral hemorrhage model was used to study the effects of ENA by administering electroacupuncture at GB20 (Fengchi) and Jiaji (EX-B2) acupoints on 24 h after the modeling, once per day for 3 days. The neurological function damage, hematoma lesion, and inflammatory cell infiltration were measured by the beam walking test and hematoxylin-eosin staining. The expression of PD-1, PD-L1, CD86, CD206, and related cytokines around the hematoma was measured by western blot, quantitative reverse transcription polymerase chain reaction, and immunofluorescence. RESULTS: The ICH group had significant neurological deficits (p < .001), hematoma lesions, and inflammatory cell infiltration. The levels of CD86 protein, inflammatory factors tumor necrosis factors (TNF)-α, interleukin (IL)-1ß, and IL-6 were increased (p < .001), while CD206 protein was reduced (p < .01), and the number of CD86+ /CD11b+ cells was also increased (p < .001) compared to the sham group. However, after ENA intervention, there was a significant reduction in neurological function damage (p < .05), infiltration of inflammatory cells, and the expression levels of CD86+ /CD11b+ cells (p < .05), resulting in the increased expression of PD-1 protein and differentiation of M2 phenotype significantly (p < .001). CONCLUSION: The study concludes that ENA could reduce neurological function damage, inhibit the expression of pro-inflammatory cytokines, and improve the infiltration of inflammatory cells to improve secondary brain injury in acute-phase intracerebral hemorrhage rats. These effects could be related to the increased expression of PD-1 around the lesion, promoting the differentiation of microglia from M1 to M2 phenotype.

[Compensation effect of re-watering after different drought stresses on source-sink metabolism during tuber expansion period of potato.] / 马铃薯块茎膨大期不同程度干旱后复水的源库补偿效应.

The compensation effect of re-watering after drought has been widely reported in various crops during different growth stages. It is considered as an important self-regulation mechanism for plants to resist abiotic stresses and also an efficient utilization of limited water resource. In this study, two rounds of re-watering after drought treatments were carried out during tuber expansion period of potato, to investigate the drought threshold of potato and explore the potential mechanisms of compensation effect with source-sink aspect. We used virus-free plantlets of "Atlantic" potato as experimental materials. Four treatments were included: sufficient water supply (W), re-watering after mild drought (D1-W), re-watering after medium drought (D2-W) and re-watering after severe drought (D3-W). The results showed that potato yield exhibited an over-compensation effect after two rounds of D1-W treatment, with water use efficiency and yield being increased by 17.5% and 6.3%, respectively, compared with the sufficient water supply. D2-W treatment had no significant effect on potato yield, but water use efficiency was increased by 8.4%, indicating a near-equivalent compensation effect. On the contrary, D3-W treatment did not show any compensation effect in yield. In addition, leaf chlorophyll content, net photosynthetic rate, and leaf area were all reduced after drought treatment, indicating a reduction in "source" size and activity. After re-watering, D1-W and D2-W treatments showed over-compensation and compensation effects through improving source supply capacity. Meanwhile, re-watering after moderate drought increased the sink activity through significantly enhancing the activities of key enzymes in tubers (sink), thus increased the average weight of tubers. In conclusion, re-watering after moderate drought stress during potato tuber expansion period had compensation and over-compensation effects on both source and sink, and thus could compensate for the drought-induced yield loss and improve water use efficiency.