106 research outputs found
Antidiabetic effect of Tibetan medicine Tang-Kang-Fu-San in db/db mice via activation of PI3K/Akt and AMPK pathways
This study was to investigate the anti-diabetic effects and molecular mechanisms of Tang-Kang-Fu-San (TKFS), a traditional Tibetan medicine, in treating type 2 diabetes mellitus of spontaneous diabetic db/db mice. Firstly HPLC fingerprint analysis was performed to gain the features of the chemical compositions of TKFS. Next different doses of TKFS (0.5 g/kg, 1.0 g/kg, and 2.0 g/kg) were administrated via oral gavage to db/db mice and their controls for 4 weeks. TKFS significantly lowered hyperglycemia and ameliorated insulin resistance (IR) in db/db mice, indicated by results from multiple tests, including fasting blood glucose test, intraperitoneal insulin and glucose tolerance tests, fasting serum insulin levels and homeostasis model assessment of IR analysis as well as histology of pancreas islets. TKFS also decreased concentrations of serum triglyceride, total and low-density lipoprotein cholesterol, even though it did not change the mouse body weights. Results from western blot and immunohistochemistry analysis indicated that TKFS reversed the down-regulation of p-Akt and p-AMPK, and increased the translocation of Glucose transporter type 4 in skeletal muscles of db/db mice. In all, TKFS had promising benefits in maintaining the glucose homeostasis and reducing IR. The underlying molecular mechanisms are related to promote Akt and AMPK activation and Glucose transporter type 4 translocation in skeletal muscles. Our work showed that multicomponent Tibetan medicine TKFS acted synergistically on multiple molecular targets and signaling pathways to treat type 2 diabetes mellitus
γδ T Cells Provide an Early Source of Interferon γ in Tumor Immunity
Interferon (IFN)-γ is necessary for tumor immunity, however, its initial cellular source is unknown. Because γδ T cells primarily produce this cytokine upon activation, we hypothesized that they would provide an important early source of IFN-γ in tumor immunosurveillance. To address this hypothesis, we first demonstrated that γδ T cell–deficient mice had a significantly higher incidence of tumor development after challenge with a chemical carcinogen methylcholanthrene (MCA) or inoculation with the melanoma cell line B16. In wild-type mice, γδ T cells were recruited to the site of tumor as early as day 3 after inoculation, followed by αβ T cells at day 5. We then used bone marrow chimeras and fetal liver reconstitutions to create mice with an intact γδ T cell repertoire but one that was specifically deficient in the capacity to produce IFN-γ. Such mice had a higher incidence of tumor development, induced either with MCA or by inoculation of B16 melanoma cells, compared with mice with IFN-γ–competent γδ T cells. Moreover, genetic deficiency of γδ T cells resulted in impaired IFN-γ production by tumor antigen-triggered αβ T cell upon immunization with tumor lysate. These results demonstrate that γδ T cells can play a necessary role in tumor immunity through provision of an early source of IFN-γ that in turn may regulate the function of tumor-triggered αβ T cells
Molybdenum disulfide nanoflowers mediated anti-inflammation macrophage modulation for spinal cord injury treatment
Spinal cord injury (SCI) can cause locomotor dysfunctions and sensory deficits. Evidence shows that functional nanodrugs can regulate macrophage polarization and promote anti-inflammatory cytokine expression, which is feasible in SCI immunotherapeutic treatments. Molybdenum disulfide (MoS2) nanomaterials have garnered great attention as potential carriers for therapeutic payload. Herein, we synthesize MoS2@PEG (MoS2 = molybdenum disulfide, PEG = poly (ethylene glycol)) nanoflowers as an effective carrier for loading etanercept (ET) to treat SCI. We characterize drug loading and release properties of MoS2@PEG in vitro and demonstrate that ET-loading MoS2@PEG obviously inhibits the expression of M1-related pro-inflammatory markers (TNF-α, CD86 and iNOS), while promoting M2-related anti-inflammatory markers (Agr1, CD206 and IL-10) levels. In vivo, the mouse model of SCI shows that long-circulating ET-MoS2@PEG nanodrugs can effectively extravasate into the injured spinal cord up to 96 h after SCI, and promote macrophages towards M2 type polarization. As a result, the ET-loading MoS2@PEG administration in mice can protect survival motor neurons, thus, reducing injured areas at central lesion sites, and significantly improving locomotor recovery. This study demonstrates the anti-inflammatory and neuroprotective activities of ET-MoS2@PEG and promising utility of MoS2 nanomaterial-mediated drug delivery
IL-10 signaling in CD4+ T cells is critical for the pathogenesis of collagen-induced arthritis
The Transcription Factor TCF1 Preserves the Effector Function of Exhausted CD8 T Cells During Chronic Viral Infection
The long-term persistence of viral antigens drives virus-specific CD8 T cell exhaustion during chronic viral infection. Yet exhausted, CD8 T cells are still endowed with certain levels of effector function, by which they can keep viral replication in check in chronic infection. However, the regulatory factors involved in regulating the effector function of exhausted CD8 T cell are largely unknown. Using mouse model of chronic LCMV infection, we found that the deletion of transcription factor TCF-1 in LCMV-specific exhausted CD8 T cells led to the profound reduction in cytokine production and degranulation. Conversely, ectopic expression of TCF-1 or using agonist to activate TCF-1 activities promotes the effector function of exhausted CD8 T cells. Mechanistically, TCF-1 fuels the functionalities of exhausted CD8 T cells by promoting the expression of an array of key effector function-associated transcription regulators, including Foxo1, Zeb2, Id3, and Eomes. These results collectively indicate that targeting TCF-1 mediated transcriptional pathway may represent a promising immunotherapy strategy against chronic viral infections by reinvigorating the effector function of exhausted virus-specific CD8 T cells
Allogenic Natural Killer Cell Immunotherapy Combined with Irreversible Electroporation for Stage IV Hepatocellular Carcinoma: Survival Outcome
Background/Aims: We evaluated the clinical effectiveness of irreversible electroporation (IRE) in combination with immunotherapy using allogenic natural killer cells (NK) for stage IV hepatocellular carcinoma (HCC). Methods: The study involved 40 patients with stage IV HCC who were divided equally into two groups: 1) simple IRE; and 2) IRE plus allogenic NK cells (IRE-NK); we mainly assessed the overall survival (OS). Results: The effect of the IRE-NK treatment was synergistic, i.e., not only did it enhance immune function, it also decreased alpha-fetoprotein expression and showed significantly good clinical effectiveness. At the median 7.6-month follow-up (range, 3.8–12.1 months), median OS was higher in the IRE-NK group (10.1 months) than in the IRE group (8.9 months, P = 0.0078). Conclusion: IRE combined with allogeneic NK cell immunotherapy significantly increases the median OS of patients with stage IV HCC
Rif1 Maintains Telomere Length Homeostasis of ESCs by Mediating Heterochromatin Silencing
SummaryTelomere length homeostasis is essential for genomic stability and unlimited self-renewal of embryonic stem cells (ESCs). We show that telomere-associated protein Rif1 is required to maintain telomere length homeostasis by negatively regulating Zscan4 expression, a critical factor for telomere elongation by recombination. Depletion of Rif1 results in terminal hyperrecombination, telomere length heterogeneity, and chromosomal fusions. Reduction of Zscan4 by shRNA significantly rescues telomere recombination defects of Rif1-depleted ESCs and associated embryonic lethality. Further, Rif1 negatively modulates Zscan4 expression by maintaining H3K9me3 levels at subtelomeric regions. Mechanistically, Rif1 interacts and stabilizes H3K9 methylation complex. Thus, Rif1 regulates telomere length homeostasis of ESCs by mediating heterochromatic silencing
Intestinal Microbiota-Derived GABA Mediates Interleukin-17 Expression during Enterotoxigenic Escherichia coli Infection
Intestinal microbiota has critical importance in pathogenesis of intestinal infection; however, the role of intestinal microbiota in intestinal immunity during enterotoxigenic Escherichia coli (ETEC) infection is poorly understood. The present study tested the hypothesis that the intestinal microbiota is associated with intestinal interleukin-17 (IL-17) expression in response to ETEC infection. Here, we found ETEC infection induced expression of intestinal IL-17 and dysbiosis of intestinal microbiota, increasing abundance of γ-aminobutyric acid (GABA)-producing Lactococcus lactis subsp. lactis. Antibiotics treatment in mice lowered the expression of intestinal IL-17 during ETEC infection, while GABA or L. lactis subsp. lactis administration restored the expression of intestinal IL-17. L. lactis subsp. lactis administration also promoted expression of intestinal IL-17 in germ-free mice during ETEC infection. GABA enhanced intestinal IL-17 expression in the context of ETEC infection through activating mechanistic target of rapamycin complex 1 (mTORC1)-ribosomal protein S6 kinase 1 (S6K1) signaling. GABA–mTORC1 signaling also affected intestinal IL-17 expression in response to Citrobacter rodentium infection and in drug-induced model of intestinal inflammation. These findings highlight the importance of intestinal GABA signaling in intestinal IL-17 expression during intestinal infection and indicate the potential of intestinal microbiota-GABA signaling in IL-17-associated intestinal diseases
Deep-ultraviolet photonics for the disinfection of SARS-CoV-2 and its variants (Delta and Omicron) in the cryogenic environment
Deep-ultraviolet (DUV) disinfection technology provides an expeditious and efficient way to suppress the transmission of coronavirus disease 2019 (COVID-19). However, the influences of viral variants (Delta and Omicron) and low temperatures on the DUV virucidal efficacy are still unknown. Here, we developed a reliable and uniform planar light source comprised of 275-nm light-emitting diodes (LEDs) to investigate the effects of these two unknown factors and delineated the principle behind different disinfection performances. We found the lethal effect of DUV at the same radiation dose was reduced by the cryogenic environment, and a negative-U large-relaxation model was used to explain the difference in view of the photoelectronic nature. The chances were higher in the cryogenic environment for the capture of excited electrons within active genetic molecules back to the initial photo-ionised positions. Additionally, the variant of Omicron required a significantly higher DUV dose to achieve the same virucidal efficacy, and this was thanks to the genetic and proteinic characteristics of the Omicron. The findings in this study are important for human society using DUV disinfection in cold conditions (e.g., the food cold chain logistics and the open air in winter), and the relevant DUV disinfection suggestion against COVID-19 is provided
Single femoral artery access is safe and feasible during transcatheter aortic valve replacement: a propensity score matched analysis
BackgroundTranscatheter aortic valve replacement (TAVR) potentially may be significantly simplified by using the single artery access (SA) technique, which does not require a secondary artery access. Nevertheless, the safety and efficacy of this technique remains unclear. Our goal was to determine if single artery access TAVR (without upgrading the sheath size) is a feasible, minimally invasive procedure.MethodsPatients with symptomatic severe aortic stenosis who underwent TAVR via the femoral artery were consecutively enrolled in this study. Eligible individuals were divided into 2 groups: the SA group and the dual artery access (DA) group. The primary end point was device success (defined by the valve academic research consortium 3, VARC 3). A 6-month follow-up and propensity score matching analyses were performed.ResultsAfter propensity score matching analysis, a total of 130 patients were included: 65 in the SA group and 65 in the DA group. The SA procedure achieved similar device success (95.4% vs. 87.7%; P = 0.115) compared with the DA procedure. The SA procedure shortened the operating time (102 min vs. 125 min; P = 0.001) but did not increase the x-ray time or dose. Both a 20 Fr and a 22 Fr sheath (without upgrading the sheath size) could be used for the SA procedure. There was no major vascular complication occurred in both groups. The incidence of minor main vascular and access complications in the SA group was comparable to those of the DA procedure (0.0% vs. 3.1%; P = 0.156).ConclusionsThe SA access procedure is a promising minimally invasive TAVR technique with a low incidence of vascular complications and a high incidence of device success. It is safe and possibly applicable in all TAVR procedures
- …