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Suneet Kaur Gautam Srivastava Amar Nath Sharma Ravinder S Jolly 《British journal of pharmacology》2015,172(9):2286-2299
Background and Purpose
Recently, we have described the use of caerulomycin A (CaeA) as a potent novel immunosuppressive agent. Immunosuppressive drugs are crucial for long-term graft survival following organ transplantation and treatment of autoimmune diseases, inflammatory disorders, hypersensitivity to allergens, etc. The objective of this study was to identify cellular targets of CaeA and decipher its mechanism of action.Experimental Approach
Jurkat cells were treated with CaeA and cellular iron content, iron uptake/release, DNA content and deoxyribonucleoside triphosphate pool determined. Activation of MAPKs; expression level of transferrin receptor 1, ferritin and cell cycle control molecules; reactive oxygen species (ROS) and cell viability were measured using Western blotting, qRT-PCR or flow cytometry.Key Results
CaeA caused intracellular iron depletion by reducing its uptake and increasing its release by cells. CaeA caused cell cycle arrest by (i) inhibiting ribonucleotide reductase (RNR) enzyme, which catalyses the rate-limiting step in the synthesis of DNA; (ii) stimulating MAPKs signalling transduction pathways that play an important role in cell growth, proliferation and differentiation; and (iii) by targeting cell cycle control molecules such as cyclin D1, cyclin-dependent kinase 4 and p21CIP1/WAF1. The effect of CaeA on cell proliferation was reversible.Conclusions and Implications
CaeA exerts its immunosuppressive effect by targeting iron. The effect is reversible, which makes CaeA an attractive candidate for development as a potent immunosuppressive drug, but also indicates that iron chelation can be used as a rationale approach to selectively suppress the immune system, because compared with normal cells, rapidly proliferating cells require a higher utilization of iron. 相似文献66.
Pravati Panda Sabita Nayak Susanta Ku. Sahoo Seetaram Mohapatra Deepika Nayak Rajalaxmi Pradhan Chanakya Nath Kundu 《RSC advances》2018,8(30):16802
The development of concise methods for the synthesis of small functionalised spirocyclic molecules is important in the search of new bioactive molecules. To contribute this, here we represent a diastereoselective oxa-hetero-Diels–Alder reaction for the synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives and studied their in vitro anticancer activities. Using previously less explored cyclic ketone i.e. indane-1,3-dione and 3-vinyl-2H-chromene derivatives, we obtained novel spiro-heterocyclic frameworks at the interphase between “drug-like” molecules and natural products. Various spiro indanone fused pyrano[3,2-c]chromene derivatives were synthesized regiospecifically bearing a quaternary stereocenter in high yields (up to 85%) with excellent diastereoselectivity in toluene using 4 Å MS as additive under reflux condition at 120 °C. In vitro cytotoxic studies of these compounds against MCF-7 (breast cancer), HCT-116 (colon cancer), H-357 (oral cancer), MD-MB-231(Breast cancer) cell lines were evaluated by MTT {3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide} assay in vitro. The screening results revealed that many of the compounds are showing moderate to high levels of anticancer activities against the tested cancer cell lines and some displayed potent inhibitory activities in comparison to the commercial anticancer drug 5-fluorouracil (5-FU). Among the series, compound 3′c showed most potent cytotoxicity (15.0–27.5 μM) in three cancer cell lines (MCF-7, HCT-116 and MD-MB-231).Synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives following hetero-Diels–Alder reaction has been demonstrated and evaluated for their in vitro anticancer activity. 相似文献
67.
Dhingra Gaurav Maji Manideepa Mandal Saikat Vaniyath Sudeep Negi Gita Nath Uttam Kumar 《Journal of thrombosis and thrombolysis》2021,52(2):504-507
Journal of Thrombosis and Thrombolysis - Thrombotic thrombocytopenic purpura (TTP) which can cause significant mortality is a thrombotic microangiopathy due to deficiency of VWF cleaving protease... 相似文献
68.
Kumar Umesh Kumar Abhai Singh Smita Arya Payal Singh Sandeep Kumar Chaurasia Rameshwar Nath Singh Anup Kumar Dinesh 《Metabolic brain disease》2021,36(5):957-968
Metabolic Brain Disease - Mild cognitive impairment (MCI) is transition phase between cognitive decline and dementia. The current study aims to investigate altered metabolic pattern in plasma of... 相似文献
69.
Aswathy R Devan Keechilat Pavithran Bhagyalakshmi Nair Maneesha Murali Lekshmi R Nath 《World journal of gastroenterology : WJG》2022,28(36):5250-5264
Transforming growth factor-beta (TGF-β) is a multifunctional cytokine that performs a dual role as a tumor suppressor and tumor promoter during cancer progression. Among different ligands of the TGF-β family, TGF-β1 modulates most of its biological outcomes. Despite the abundant expression of TGF-β1 in the liver, steatosis to hepatocellular carcinoma (HCC) progression triggers elevated TGF-β1 levels, contributing to poor prognosis and survival. Additionally, elevated TGF-β1 levels in the tumor microenvironment create an immunosuppressive stage via various mechanisms. TGF-β1 has a prime role as a diagnostic and prognostic biomarker in HCC. Moreover, TGF-β1 is widely studied as a therapeutic target either as monotherapy or combined with immune checkpoint inhibitors. This review provides clinical relevance and up-to-date information regarding the potential of TGF-β1 in diagnosis, prognosis, and therapy against HCC. 相似文献
70.
Jaya Prakash Nath Ambinathan Vikas S. Sridhar Yuliya Lytvyn Leif Erik Lovblom Hongyan Liu Petter Bjornstad Bruce A. Perkins Julie A. Lovshin David Z.I. Cherney 《Journal of diabetes and its complications》2021,35(5):107880
The renin angiotensin aldosterone system (RAAS) is associated with renal disease and inflammation in a diabetes setting, however, little is known about the implicated mechanisms in individuals with long standing diabetes. Accordingly, our aim was to perform an observational study to quantify urinary excretion of inflammatory biomarkers in participants with long standing type 1 diabetes (T1D) (with and without diabetic kidney disease [DKD]) and controls, at baseline and in response to RAAS activation. GFRINULIN, ERPFPAH, and 42 urine inflammatory biomarkers were measured in 74 participants with T1D for ≥50 years (21 with DKD and 44 without DKD [DKD resistors]) and 73 healthy controls. Additionally, inflammatory biomarkers were measured before and after an angiotensin II infusion (ANGII, 1 ng?kg?1?min?1). Significantly lower urinary excretion of cytokines (IL-18, IL-1RA, IL-8), chemokines (MCP1, RANTES) and growth factors (TGF-α, PDGFAA, PDGFBB, VEGF-A) was observed in participants with T1D at baseline compared to controls. Urinary IL-6 was higher in DKD than in DKD resistors in an exploratory analysis unadjusted for multiple comparisons. In T1D only, lower GFRINULIN correlated with greater excretion of proinflammatory biomarkers (IL-18, IP-10, & RANTES), growth factors (PDGF-AA & VEGFAA), and chemokines (eotaxin & MCP-1). ANGII increased 31 of 42 inflammatory biomarkers in T1D vs controls (p < 0.05), regardless of DKD resistor status. In conclusion, lower GFR and intra-renal RAAS activation were associated with increased inflammation even after longstanding T1D. The increased urinary IL-6 in patients with DKD requires further investigation to determine whether IL-6 is a candidate protective biomarker for prognostication or targeted therapy in DKD. 相似文献