Dysbiosis, departure of the gut microbiome from a healthy state, has been suggested to be a powerful biomarker of disease incidence and progression. Diagnostic applications have been proposed for inflammatory bowel disease diagnosis and prognosis, colorectal cancer prescreening and therapeutic choices in melanoma. Noninvasive sampling could facilitate large-scale public health applications, including early diagnosis and risk assessment in metabolic and cardiovascular diseases. To understand the generalizability of microbiota-based diagnostic models of metabolic disease, we characterized the gut microbiota of 7,009 individuals from 14 districts within 1 province in China. Among phenotypes, host location showed the strongest associations with microbiota variations. Microbiota-based metabolic disease models developed in one location failed when used elsewhere, suggesting that such models cannot be extrapolated. Interpolated models performed much better, especially in diseases with obvious microbiota-related characteristics. Interpolation efficiency decreased as geographic scale increased, indicating a need to build localized baseline and disease models to predict metabolic risks.
Vascular calcification (VC) is a major risk factor for cardiovascular mortality in chronic renal failure (CRF) patients, but the pathogenesis remains partially unknown and effective therapeutic targets should be urgently explored. Here we pursued the therapeutic role of rapamycin in CRF-related VC. Mammalian target of rapamycin (mTOR) signal was activated in the aortic wall of CRF rats. As expected, oral rapamycin administration significantly reduced VC by inhibiting mTOR in rats with CRF. Further in vitro results showed that activation of mTOR by both pharmacological agent and genetic method promoted, while inhibition of mTOR reduced, inorganic phosphate-induced vascular smooth muscle cell (VSMC) calcification and chondrogenic/osteogenic gene expression, which were independent of autophagy and apoptosis. Interestingly, the expression of Klotho, an antiaging gene that suppresses VC, was reduced in calcified vasculature, whereas rapamycin reversed membrane and secreted Klotho decline through mTOR inhibition. When mTOR signaling was enhanced by either mTOR overexpression or deletion of tuberous sclerosis 1, Klotho mRNA was further decreased in phosphate-treated VSMCs, suggesting a vital association between mTOR signaling and Klotho expression. More importantly, rapamycin failed to reduce VC in the absence of Klotho by using either siRNA knockdown of Klotho or Klotho knockout mice. Thus, Klotho has a critical role in mediating the observed decrease in calcification by rapamycin in vitro and in vivo.
The transcription factor, Zinc finger of the cerebellum (ZIC1), plays a crucial role in vertebrate development. Recently, ZIC1 has also been found to participate in the progression of human cancers, including medulloblastomas, endometrial cancers, and mesenchymal neoplasms. However, the function of ZIC1 in colon cancer progression has not been defined. In this study, we demonstrate ZIC1 to be silenced or significantly downregulated in colon cancer cell lines. These effects were reversed by demethylation treatment with 5-aza-2′-deoxycytidine (Aza). ZIC1 expression is also significantly downregulated in primary colorectal cancer tissues relative to adjacent non-tumor tissues (p = 0.0001). Furthermore, methylation of ZIC1 gene promoter is frequently detected in primary tumor tissues (85%, 34/40), but not in adjacent non-tumor tissues. Ectopic expression of ZIC1 suppresses cell proliferation and induces apoptosis, which is associated with MAPK and PI3K/Akt pathways, as well as the Bcl-xl/Bad/Caspase3 cascade. To identify target candidates of ZIC1, we employed cDNA microarray and found that 337 genes are downregulated and 95 genes upregulated by ectopic expression of ZIC1, which were verified by 10 selected gene expressions by qRT-PCR. Taken together, our results suggest that ZIC1 may potentially function as a tumor suppressor gene, which is downregulated through promoter hypermethylation in colorectal cancers.
Background: Aortic dissection is a severe inflammatory vascular disease with high mortality and limited therapeutic options. The hallmarks of aortic dissection comprise aortic inflammatory cell infiltration and elastic fiber disruption, highlighting the involvement of macrophage. Here a role for macrophage hypoxiainducible factor 1-alpha (HIF-1 α) in aortic dissection was uncovered.Methods: Immunochemistry, immunofluorescence, western blot and qPCR were performed to test the change of macrophage HIF-1 α in two kinds of aortic dissection models and human tissues. Metabolomics and Seahorse extracellular flux analysis were used to detect the metabolic state of macrophages involved in the development of aortic dissection. Chromatin Immunoprecipitation (ChIP), enzyme-linked immunosorbent assay (ELISA) and cytometric bead array (CBA) were employed for mechanistic studies. Findings: Macrophages involved underwent distinct metabolic reprogramming, especially fumarate accumulation, thus inducing HIF-1 α activation in the development of aortic dissection in human and mouse models. Mechanistic studies revealed that macrophage HIF-1 α activation triggered vascular inflammation, extracellular matrix degradation and elastic plate breakage through increased a disintegrin and metallopeptidase domain 17 (ADAM17), identified as a novel target gene of HIF-1 α. A HIF-1 α specific inhibitor acriflavine elicited protective effects on aortic dissection dependent on macrophage HIF-1 α. Interpretation: This study reveals that macrophage metabolic reprogramming activates HIF-1 α and subsequently promotes aortic dissection progression, suggesting that macrophage HIF-1 α inhibition might be a potential therapeutic target for treating aortic dissection.
The aim of the present study was to investigate the neuroprotective mechanism of the miR-9-mediated activation of the nuclear factor (NF)-κB signaling pathway by electroacupuncture (EA) stimulation of the Quchi (LI11) and Zusanli (ST36) acupoints in a rat model of middle cerebral artery occlusion (MCAO). The present study demonstrated that EA alleviated the symptoms of neurological deficits and reduced the infarct volume in the rat brains. The expression of miR-9 in the peri-infarct cortex was increased in the EA group compared with the MCAO group, and the expression of NF-κB signaling pathway-associated factors, NF-κB p65, tumor necrosis factor (TNF)-α and interleukin (IL)-1β were reduced. Notably, miR-9 inhibitors were revealed to have the ability to suppress EA-alleviated cerebral inflammation and the expression of NF-κB downstream-related factors, NF-κB p65, TNF-α and IL-1β, and caused no alteration on the level of NF-κB upstream-related protein inhibitor of κBα, suggesting that the cerebral protective efficacy of EA targets miR-9-mediated NF-κB downstream pathway following ischemic stroke.
Detection of pathogens with single‐nucleotide variations is indispensable for the disease tracing, but remains technically challenging. The D614G mutation in the SARS‐CoV‐2 spike protein is known to markedly enhance viral infectivity but is difficult to detect. Here, we report an effective approach called “synthetic mismatch integrated crRNA guided Cas12a detection” (symRNA‐Cas12a) to detect the D614 and G614 variants effectively. Using this method, we systemically screened a pool of crRNAs that contain all the possible nucleotide substitutions covering the ‐2 to +2 positions around the mutation and identify one crRNA that can efficiently increase the detection specificity by 13‐fold over the ancestral crRNA. With this selected crRNA, the symRNA‐Cas12a assay can detect as low as 10 copies of synthetic mutant RNA and the results are confirmed to be accurate by Sanger sequencing. Overall, we have developed the symRNA‐Cas12a method to specifically, sensitively and rapidly detect the SARS‐CoV‐2 D614G mutation.
Uncontrolled activity of T cells mediates autoimmune and inflammatory diseases such as multiple sclerosis, inflammatory bowel diseases, rheumatoid arthritis, type 1 diabetes, and atherosclerosis. Recent findings suggest that enhanced activity of interleukin-17 (IL-17) producing T helper 17 cells (Th17 cells) plays an important role in autoimmune diseases and inflammatory diseases. Previous papers have revealed that a lipid-lowering synthetic ligand of peroxisome proliferator-activated receptor α (PPARα), fenofibrate, alleviates both atherosclerosis and a few nonlipid-associated autoimmune diseases such as autoimmune colitis and multiple sclerosis. However, the link between fenofibrate and Th17 cells is lacking. In the present study, we hypothesized that fenofibrate inhibited the differentiation of Th17 cells. Our results showed that fenofibrate inhibited transforming growth factor-β (TGF-β) and IL-6-induced differentiation of Th17 cells in vitro. However, other PPARα ligands such as WY14643, GW7647 and bezafibrate did not show any effect on Th17 differentiation, indicating that this effect of fenofibrate might be PPARα independent. Furthermore, our data showed that fenofibrate reduced IL-21 production and STAT3 activation, a critical signal in the Th17 differentiation. Thus, by ameliorating the differentiation of Th17 cells, fenofibrate might be beneficial for autoimmunity and inflammatory diseases.
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