Interlace between Chromatin Structure, DNA Repair and Ubiquitination

Chromatin remodeling, ubiquitylation, and DNA damage repair may be regarded as three discrete processes, but in fact, they are three extremely important interlinked processes that are imperative for the sustenance for life. Discrepancies in one will have outcomes that will affect the other processes direly. Exogenous and endogenous factors persistently affect the DNA by inducing damage and modifications. To sustain the integrity of life, these challenges need to be combated efficiently. For the preservation of the structural and functional components of the genome, nature has allowed them to evolve numerous pathways that constantly work to repair the induced damage. This sort of response is termed as DDR (DNA damage response) that include BER and NER (base excision and nucleotide excision repair, respectively) and non-homologous end joining and homologous recombination (NHEJ & HR). Since the DNA in cells is exceedingly organized and compressed, hence any process that utilizes DNA as its substrate requires essential remodeling of the chromatin structure. The chapter emphasizes on the phenomenon of chromatin remodeling and ubiquitylation which subsequently affects the integral process of DNA damage repair

Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Abstract Background Synovial fibroblasts in rheumatoid arthritis (RAFLS) exhibit a pathological aberration of glycolysis and glutaminolysis. Henceforth, we aimed to investigate if dual inhibition of these pathways by phytobiological compound c28MS has the potential of synergistic therapy for arthritis by targeting both glucose and glutamine metabolism. Methods The presence of HK2 and GLS across various cell types and associated gene expression in human synovial cells and a murine model of arthritis was evaluated by scRNA-seq. The metabolic profiling of RAFLS cells was done using H1-nuclear magnetic resonance spectroscopy under glycolytic and glutaminolytic inhibitory conditions by incubating with 3-bromopyruvate, CB839, or dual inhibitor c28MS. FLS functional analysis was conducted under similar conditions. ELISA was employed for the quantification of IL-6, CCL2, and MMP3. K/BxN sera was administered to mice to induce arthritis for in vivo arthritis experiments. Results scRNA-seq analysis revealed that many fibroblasts expressed Hk2 along with Gls with several genes including Ptgs2, Hif1a, Timp1, Cxcl5, and Plod2 only associated with double-positive fibroblasts, suggesting that dual inhibition can be an attractive target for fibroblasts. Metabolomic and functional analysis revealed that c28MS decreased the aggressive behavior of RAFLS by targeting both upregulated glycolysis and glutaminolysis. c28MS administered in vivo significantly decreased the severity of arthritis in the K/BxN model. Conclusion Our findings imply that dual inhibition of glycolysis and glutaminolysis could be an effective approach for the treatment of RA. It also suggests that targeting more than one metabolic pathway can be a novel treatment approach in non-cancer diseases

Docking and Molecular Dynamics Study to Identify Novel Phytobiologics from Dracaena trifasciata against Metabolic Reprogramming in Rheumatoid Arthritis

Enhancement of glycolysis and glutaminolysis are the two most common modalities associated with metabolic reprogramming in rheumatoid arthritis (RA). This enhancement is concomitant to the upregulation of hexokinase 2 (HK2) and glutaminase 1 (GLS1). Hence, the current study was undertaken to identify potential phytobiological inhibitors against HK2 and GLS1, from Dracaena (Sansevieria) trifasciata, an indigenous ethnomedicinal plant found in Pakistan, using computational analysis. Phytobiologics from Dracaena trifasciata were assessed for their ability to co-inhibit HK2 and GLS1 via molecular docking and molecular dynamics simulations. The results underscored seven phytobiologics with promising binding affinities for both HK2 and GLS1. Molecular dynamics simulations further elucidated that all seven identified phytobiologics inhibited HK2 by forming stable complexes but only five amongst the seven had the potential to form stable complexes with GLS1 in real time, thereby implying the potential of co-inhibition for these five compounds. Compound 28MS exhibited an equally strong binding profile for both HK2 (−8.19 kcal/mol) and GLS1 (−8.99 kcal/mol). Furthermore, it exhibited a similar trend in stability during simulation for both targets. Our results serve as a primer for a more lucid understanding towards co-inhibition of HK2 and GLS1 using multiple computational approaches. The identified phytobiologics should undergo in-vitro and in-vivo validation to corroborate their therapeutic potential in RA

Efficacy of Intralesion Injection of Combined 5-Flourouracil and Triamcinolone versus Triamcinalone alone in Keloids and Hypertrophic Scars: A Comparative Analysis

Objective: The treatment of keloids and hypertrophic scars is challenging and controversial. The therapeutic agents found in the literature include silicone sheets, compression garments, corticosteroid injections, 5-fluorouracil (5-FU), bleomycin and interferon, topical imiquimod, cryotherapy, radiation, and laser or light-based therapies. Triamcinolone acetonide (TCA), a corticosteroid, considered first line treatment for the prevention and treatment of keloids and hypertrophic scars. To compare the efficacy of triamcinolone acetonide alone and triamcinolone acetonide plus 5-florouracil for treating keloids and hypertrophic scars in burn patients. Methodology: In this study, the patients were divided into two groups A and B on the basis of treatment regimen, i.e. Group A (TCA alone) and Group B (5FU+TCA). The efficacy of both treatments was compared for improvement in Vancouver scar scale (VSS) and pruritus scale. Results: The mean VSS score pretreatment was calculated as 10.74±2.36 in Group A and 10.27±3.14 in Group B.  Post-treatment, it was reduced to 5.58±1.04 in Group-A and 3.41±2.11 in Group-B. The comparison of efficacy shows an improvement of 65.80% in Group A and 75.07% in Group B; the p value was 0.047, showing a significant difference. Conclusion: Combination therapy of intra-lesion injection of triamcinolone acetonide and 5-florouracil has significantly higher efficacy as compared to triamcinolone acetonide alone for the treatment of keloids and hypertrophic scars, but necessary precautions have to be taken

Additional file 2 of Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Additional file 2: Figure S2. Color scale encoded heat maps illustrating variations in the concentration of various metabolites between control and treatment groups in RAFLS A glucose medium (25mM of glucose and 6mM of glutamine) and B low glucose medium (2mM of glucose and 6mM of glutamine) respectively

Additional file 5 of Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Additional file 5. Details of genes found in double negative, Hk2 positive, Gls positive and double positive fibroblasts in murine STIA

Additional file 3 of Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Additional file 3: Figure S3. Effect of c28MS on viability of RAFLS (n=3) A glucose medium (25mM of glucose and 6mM of glutamine) and B low glucose medium (2mM of glucose and 6mM of glutamine)

Additional file 1 of Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Additional file 1: Figure S1. A scRNA-seq UMAP of all cells sequenced as described in Zhang et al., 2019 [25]. B,C Segregation of synovial fibroblasts from Zhang et al., 2019 [25] in to GLS positive, HK2 positive, double negative and double positive cells

Additional file 4 of Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Additional file 4: Figure S4. Expression of Ccl2, Mmp3 and Il6 in double positive and negative fibroblasts at different stages of the disease

Additional file 6 of Dual inhibition of glycolysis and glutaminolysis for synergistic therapy of rheumatoid arthritis

Additional file 6. List of up-and down regulated genes in double positive fibroblasts for the different disease stages