Role of the PERK-eIF2α-CHOP Signaling Pathway in the Effect of Needle Knife Therapy on Knee Joint Chondrocyte Apoptosis.

Needle knife therapy, a form of acupuncture and moxibustion, has been widely used in the clinical treatment of knee osteoarthritis (KOA). However, the mechanism is not clear. Therefore, we studied the mechanisms of action of needle knife intervention on KOA in rabbits, with the PERK-eIF2α-CHOP pathway as a starting point, in order to determine the mechanism underlying knee joint chondrocyte apoptosis. Apoptosis and ultrastructural changes in the articular cartilage were examined by pathological study and transmission electron microscopy, and PERK, eIF2α, and CHOP mRNA and protein levels were detected by qRT-PCR and western blot, respectively. PERK, eIF2α, and CHOP protein levels were significantly higher in the model group than in the normal group (P < 0.01) and were considerably downregulated in the needle knife and the medicine groups compared to the model group (P < 0.01). The eIF2α, p-eIF2α, and CHOP protein levels were not significantly different between the needle knife and medicine groups. The PERK, eIF2α, and CHOP mRNA levels in the drug group were higher than those in the needle knife group (P < 0.01). Needle knife therapy can regulate PERK-eIF2α-CHOP signaling pathway, which could be one of the mechanisms by which it affects chondrocyte apoptosis in KOA rabbits.

Down-regulation of Helios Expression in Tregs from Patients with Hypertension.

Regulatory T cells (Tregs) play a pivotal role in the pathological development of hypertension. Helios, a transcription factor from the Ikaros family, was recently reported to be a bona fide marker for natural Tregs or activated Tregs with suppression function, however, little has been known about its role in hypertension. This study was aimed to find whether Helios+ Tregs really play a vital role in hypertension. A total of 60 hypertension patients, and 46 normotension subjects were enrolled in this study. Frequencies of different Tregs subsets in peripheral blood were measured by flow cytometry. Plasma cytokine level was determined by ELISA. The mRNA expression of Foxp3 and Helios in purified CD4+ T cells was detected by RT-PCR. Proportion of CD4+Foxp3+Helios+ Tregs was decreased significantly in patients with hypertension (62.52%±1.18% vs. 71.89%±1.03%, P<0.01), and it was correlated with plasma level of IL-10 positively (a=0.505, P<0.05) and plasma level of IFN-gamma negatively (r=-0.551, P<0.05). The mRNA expression of Foxp3 (7.23±1.00 vs. 10.58±0.54, P<0.05) and Helios (8.47±0.95 vs. 15.52±2.0, P<0.05) was decreased in CD4+ T cells from patients with hypertension. Helios+ Tregs were decreased in patients with hypertension and may play a protective role in hypertension progression.

The conditioned medium of human mesenchymal stromal cells reduces irradiation-induced damage in cardiac fibroblast cells.

Recently, multipotent mesenchymal stromal cell (MSC) treatment has attracted special attention as a new alternative strategy for stimulating regeneration. Irradiation myocardial fibrosis (IMF) is a major complication associated with total body irradiation for hematopoietic stem cell transplantation, nuclear accidents, and thoracic radiotherapy for lung cancer, esophageal cancer, proximal gastric cancer, breast cancer, thymoma, and lymphoma. The aim of the present study was to assess the therapeutic paracrine effects of human umbilical cord-derived mesenchymal stromal cells (UC-MSCs) in the cell model of IMF. For this purpose, primary human cardiac fibroblasts (HCF) cells were irradiated and cultured with the conditioned medium of UC-MSCs (MSCCM). MSCCM promoted cell viability, reduced collagen deposition as measured by Sircol assay and qPCR (Col1A1 and Col1A2), prevented oxidative stress and increased antioxidant status (as measured by malondialdehyde content and the activities and mRNA levels of antioxidant enzymes), and reduced pro-fibrotic TGF-ß1, IL-6 and IL-8 levels (as examined by ELISA kit and qPCR). Pretreatment with inhibitor of NF-κB led to a decrease in the levels of TGF-ß1 in cell lysate of HCF cells by ELISA kit. Furthermore, we also found that MSCCM prevented NF-κB signaling pathway activation for its proinflammatory actions induced by irradiation. Taken together, our data suggest that MSCCM could reduce irradiation-induced TGF-ß1 production through inhibition of the NF-κB signaling pathway. These data provide new insights into the functional actions of MSCCM on irradiation myocardial fibrosis.

Effects of oral and subcutaneous administration of HSP60 on myeloid-derived suppressor cells and atherosclerosis in ApoE-/- mice.

HSP60 has been proved to be closely related to atherosclerosis due to its antigenicity. To determine this antigenicity effect, the ApoE-/- mice were fed with western-type diet and HSP60 was administrated orally or subcutaneously (SC) for potential vaccine against atherosclerosis. Here, we observed the ApoE-/- mice with oral HSP60 administration group showed a significant reduction in plaque size at the aortic root; accompanied by increased MSDCs (CD11b+Gr1+) in peripheral blood and spleen which was mostly composed of M-MDSCs (CD11b+LY6G-LY6Chigh), and increased plasma IL-10 and splenic Foxp3, Arg1, iNOS mRNA as well as decreased plasma IFN-γ and splenic T-bet mRNA compared to control group. Surprisingly, ApoE-/- mice with subcutaneous HSP60 administration group showed contrary results and their MDSCs were mostly composed of G-MDSCs (CD11b+LY6G+LY6Clow). As expected, both PBS-oral and PBS-SC groups showed no significant effects on both the immune response and atherosclerotic plaque formation. In contrast, subcutaneous administration of HSP60 causes the opposite response. Thus, we propose the proper method for administering HSP60 as a new immunologic agent for prevention and treatment of atherosclerosis.

A functional variant in ST2 gene is associated with risk of hypertension via interfering MiR-202-3p.

Recent studies have suggested that interleukin 1 receptor-like 1 (ST2) plays a critical role in pathogenesis of several cardiovascular disease conditions. In this study, we examined association of 13 single nucleotide polymorphisms (SNPs) of ST2 gene with essential hypertension (EH) risk in 1151 patients with EH and 1135 controls. Our study showed that variants rs11685424, rs12999364 and rs3821204 are highly associated with an increase in risk of EH, while rs6543116 is associated with a decrease risk of EH. Notably, in silico analyses suggested the G>C change of rs3821204, which located within the 3'UTR of soluble ST2 mRNA, disrupted a putative binding site for miR202-3p. Functional analyses suggested that miR-202-3p significantly decreased soluble ST2-G mRNA stability and inhibited its endogenous expression. Furthermore, we found increased plasma-soluble ST2 (sST2) level was highly associated with CC genotype of rs3821204 in vivo. Taken together, our findings provide the first evidence that genetic variants in ST2 gene are associated with EH risk and variant rs3821204 may influence the development of EH by controlling sST2 expression.

Expansion of myeloid-derived suppressor cells in patients with acute coronary syndrome.

AIM: The aim of this study was to explore whether the circulating frequency and function of myeloid-derived suppressor cells (MDSCs) are altered in patients with acute coronary syndrome (ACS). METHODS: The frequency of MDSCs in peripheral blood was determined by flow cytometry, and mRNA expression in purified MDSCs was analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR). The suppressive function of MDSCs isolated from different groups was also determined. The plasma levels of certain cytokines were determined using Bio-Plex Pro™ Human Cytokine Assays. RESULTS: The frequency of circulating CD14(+)HLA-DR(-/low) MDSCs; arginase-1 (Arg-1) expression; and plasma levels of interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, and IL-33 were markedly increased in ACS patients compared to stable angina (SA) or control patients. Furthermore, MDSCs from ACS patients were more potent suppressors of T-cell proliferation and IFN-γ production than those from the SA or control groups at ratios of 1:4 and 1:2; this effect was partially mediated by Arg-1. In addition, the frequency of MDSCs was positively correlated with plasma levels of IL-6, IL-33, and TNF-α. CONCLUSIONS: We observed an increased frequency and suppressive function of MDSCs in ACS patients, a result that may provide insights into the mechanisms involved in ACS.

Regulatory T cells protect fine particulate matter-induced inflammatory responses in human umbilical vein endothelial cells.

OBJECTIVE: To investigate the role of CD4(+)CD25(+) T cells (Tregs) in protecting fine particulate matter (PM-) induced inflammatory responses, and its potential mechanisms. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with graded concentrations (2, 5, 10, 20, and 40 µg/cm(2)) of suspension of fine particles for 24h. For coculture experiment, HUVECs were incubated alone, with CD4(+)CD25(-) T cells (Teff), or with Tregs in the presence of anti-CD3 monoclonal antibodies for 48 hours, and then were stimulated with or without suspension of fine particles for 24 hours. The expression of adhesion molecules and inflammatory cytokines was examined. RESULTS: Adhesion molecules, including vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), and inflammatory cytokines, such as interleukin (IL-) 6 and IL-8, were increased in a concentration-dependent manner. Moreover, the adhesion of human acute monocytic leukemia cells (THP-1) to endothelial cells was increased and NF- κ B activity was upregulated in HUVECs after treatment with fine particles. However, after Tregs treatment, fine particles-induced inflammatory responses and NF- κ B activation were significantly alleviated. Transwell experiments showed that Treg-mediated suppression of HUVECs inflammatory responses impaired by fine particles required cell contact and soluble factors. CONCLUSIONS: Tregs could attenuate fine particles-induced inflammatory responses and NF- κ B activation in HUVECs.

What interests them in the pictures?--differences in eye-tracking between rhesus monkeys and humans.

Studies estimating eye movements have demonstrated that non-human primates have fixation patterns similar to humans at the first sight of a picture. In the current study, three sets of pictures containing monkeys, humans or both were presented to rhesus monkeys and humans. The eye movements on these pictures by the two species were recorded using a Tobii eye-tracking system. We found that monkeys paid more attention to the head and body in pictures containing monkeys, whereas both monkeys and humans paid more attention to the head in pictures containing humans. The humans always concentrated on the eyes and head in all the pictures, indicating the social role of facial cues in society. Although humans paid more attention to the hands than monkeys, both monkeys and humans were interested in the hands and what was being done with them in the pictures. This may suggest the importance and necessity of hands for survival. Finally, monkeys scored lower in eye-tracking when fixating on the pictures, as if they were less interested in looking at the screen than humans. The locations of fixation in monkeys may provide insight into the role of eye movements in an evolutionary context.