CXCL16-dependent scavenging of oxidized lipids by islet macrophages promotes differentiation of pathogenic CD8+ T cells in diabetic autoimmunity.

The pancreatic islet microenvironment is highly oxidative, rendering ß cells vulnerable to autoinflammatory insults. Here, we examined the role of islet resident macrophages in the autoimmune attack that initiates type 1 diabetes. Islet macrophages highly expressed CXCL16, a chemokine and scavenger receptor for oxidized low-density lipoproteins (OxLDLs), regardless of autoimmune predisposition. Deletion of Cxcl16 in nonobese diabetic (NOD) mice suppressed the development of autoimmune diabetes. Mechanistically, Cxcl16 deficiency impaired clearance of OxLDL by islet macrophages, leading to OxLDL accumulation in pancreatic islets and a substantial reduction in intra-islet transitory (Texint) CD8+ T cells displaying proliferative and effector signatures. Texint cells were vulnerable to oxidative stress and diminished by ferroptosis; PD-1 blockade rescued this population and reversed diabetes resistance in NOD.Cxcl16-/- mice. Thus, OxLDL scavenging in pancreatic islets inadvertently promotes differentiation of pathogenic CD8+ T cells, presenting a paradigm wherein tissue homeostasis processes can facilitate autoimmune pathogenesis in predisposed individuals.

ER-PM membrane contact site regulation by yeast ORPs and membrane stress pathways.

In yeast, at least seven proteins (Ice2p, Ist2p, Scs2/22p, Tcb1-Tcb3p) affect cortical endoplasmic reticulum (ER) tethering and contact with the plasma membrane (PM). In Δ-super-tether (Δ-s-tether) cells that lack these tethers, cortical ER-PM association is all but gone. Yeast OSBP homologue (Osh) proteins are also implicated in membrane contact site (MCS) assembly, perhaps as subunits for multicomponent tethers, though their function at MCSs involves intermembrane lipid transfer. Paradoxically, when analyzed by fluorescence and electron microscopy, the elimination of the OSH gene family does not reduce cortical ER-PM association but dramatically increases it. In response to the inactivation of all Osh proteins, the yeast E-Syt (extended-synaptotagmin) homologue Tcb3p is post-transcriptionally upregulated thereby generating additional Tcb3p-dependent ER-PM MCSs for recruiting more cortical ER to the PM. Although the elimination of OSH genes and the deletion of ER-PM tether genes have divergent effects on cortical ER-PM association, both elicit the Environmental Stress Response (ESR). Through comparisons of transcriptomic profiles of cells lacking OSH genes or ER-PM tethers, changes in ESR expression are partially manifested through the induction of the HOG (high-osmolarity glycerol) PM stress pathway or the ER-specific UPR (unfolded protein response) pathway, respectively. Defects in either UPR or HOG pathways also increase ER-PM MCSs, and expression of extra "artificial ER-PM membrane staples" rescues growth of UPR mutants challenged with lethal ER stress. Transcriptome analysis of OSH and Δ-s-tether mutants also revealed dysregulation of inositol-dependent phospholipid gene expression, and the combined lethality of osh4Δ and Δ-s-tether mutations is suppressed by overexpression of the phosphatidic acid biosynthetic gene, DGK1. These findings establish that the Tcb3p tether is induced by ER and PM stresses and ER-PM MCSs augment responses to membrane stresses, which are integrated through the broader ESR pathway.

Increased Phospholipid Flux Bypasses Overlapping Essential Requirements for the Yeast Sac1p Phosphoinositide Phosphatase and ER-PM Membrane Contact Sites.

In budding yeast cells, much of the inner surface of the plasma membrane (PM) is covered with the endoplasmic reticulum (ER). This association is mediated by seven ER membrane proteins that confer cortical ER-PM association at membrane contact sites (MCSs). Several of these membrane "tether" proteins are known to physically interact with the phosphoinositide phosphatase Sac1p. However, it is unclear how or if these interactions are necessary for their interdependent functions. We find that SAC1 inactivation in cells lacking the homologous synaptojanin-like genes INP52 and INP53 results in a significant increase in cortical ER-PM MCSs. We show in sac1Δ, sac1tsinp52Δ inp53Δ, or Δ-super-tether (Δ-s-tether) cells lacking all seven ER-PM tethering genes that phospholipid biosynthesis is disrupted and phosphoinositide distribution is altered. Furthermore, SAC1 deletion in Δ-s-tether cells results in lethality, indicating a functional overlap between SAC1 and ER-PM tethering genes. Transcriptomic profiling indicates that SAC1 inactivation in either Δ-s-tether or inp52Δ inp53Δ cells induces an ER membrane stress response and elicits phosphoinositide-dependent changes in expression of autophagy genes. In addition, by isolating high-copy suppressors that rescue sac1Δ Δ-s-tether lethality, we find that key phospholipid biosynthesis genes bypass the overlapping function of SAC1 and ER-PM tethers and that overexpression of the phosphatidylserine/phosphatidylinositol-4-phosphate transfer protein Osh6 also provides limited suppression. Combined with lipidomic analysis and determinations of intracellular phospholipid distributions, these results suggest that Sac1p and ER phospholipid flux controls lipid distribution to drive Osh6p-dependent phosphatidylserine/phosphatidylinositol-4-phosphate counter-exchange at ER-PM MCSs.

Arid5a, an RNA-Binding Protein in Immune Regulation: RNA Stability, Inflammation, and Autoimmunity.

AT-rich interactive domain 5A (ARID5A/Arid5a) is a known cofactor of transcription factors (TFs) that contributes to cell growth and differentiation. It has recently been recognized for its unique function in the stabilization of mRNA, which is associated with inflammatory autoimmune diseases. Studies have revolutionized our understanding of the post-transcriptional regulation of inflammatory genes by revealing the fundamental events underpinning novel functions and activities of Arid5a. We review current research on Arid5a, which has focused our attention towards the therapeutic potential of this factor in the putative treatment of inflammatory and autoimmune disorders, including experimental autoimmune encephalomyelitis and sepsis in mice.

Controlled Transport of Individual Microparticles Using Dielectrophoresis.

A dielectrophoretic device employing a planar array of microelectrodes is designed for controlled transport of individual microparticles. By exciting the electrodes in sequence, a moving dielectrophoretic force is created that can drag a particle across the electrodes in a straight line. The electrode shapes are designed to counter any lateral drift of the trapped particle during transport. This facilitates single particle transport by creating a narrow two-dimensional corridor for the moving dielectrophoretic force to operate on. The design and analysis processes are discussed in detail. Numerical simulations are performed to calculate the electromagnetic field distribution and the generated dielectrophoretic force near the electrodes. The Langevin equation is used for analyzing the trajectory of a microparticle under the influence of the external forces. The simulations show how the designed electrode geometry produces the necessary lateral confinement required for successful particle transport. Finally, experimental results are presented showing controlled bidirectional linear transport of single polystyrene beads of radius 10 and 5 µm for a distances 840 and 1100 µm, respectively. The capabilities of the proposed platform make it suitable for micro total analysis systems (µTAS) and lab-on-a-chip (LOC) applications.

A Study to Compare Ultrasound-guided and Clinically Guided Fluid Management in Children with Septic Shock.

Background: To evaluate the role of ultrasound during initial fluid resuscitation along with clinical guidance in reducing the incidence of fluid overload on day 3 in children with septic shock. Materials and methods: It was a prospective, parallel limb open-labeled randomized controlled superiority trial done in the PICU of a government-aided tertiary care hospital in Eastern India. Patient enrolment took place between June 2021 and March 2022. Fifty-six children aged between 1 month and 12 years, with proven or suspected septic shock, were randomized to receive either ultrasound-guided or clinically guided fluid boluses (1:1 ratio) and subsequently followed up for various outcomes. The primary outcome was frequency of fluid overload on day 3 of admission. The treatment group received ultrasound-guided fluid boluses along with the clinical guidance and the control group received the same but without ultrasound guidance upto 60 mL/kg of fluid boluses. Results: The frequency of fluid overload on day 3 of admission was significantly lower in the ultrasound group (25% vs 62%, p = 0.012) as was the median (IQR) cumulative fluid balance percentage on day 3 [6.5 (3.3-10.3) vs 11.3 (5.4-17.5), p = 0.02]. The amount of fluid bolus administered was also significantly lower by ultrasound [median 40 (30-50) vs 50 (40-80) mL/kg, p = 0.003]. Resuscitation time was shorter in the ultrasound group (13.4 ± 5.6 vs 20.5 ± 8 h, p = 0.002). Conclusion: Ultrasound-guided fluid boluses were found to be significantly better than clinically guided therapy, in preventing fluid overload and its associated complications in children with septic shock. These factors make ultrasound a potentially useful tool for resuscitation of children with septic shock in the PICU. How to cite this article: Kaiser RS, Sarkar M, Raut SK, Mahapatra MK, Uz Zaman MA, Roy O, et al. A Study to Compare Ultrasound-guided and Clinically Guided Fluid Management in Children with Septic Shock. Indian J Crit Care Med 2023;27(2):139-146.

Molecular details of aluminium-amyloid ß peptide interaction by nuclear magnetic resonance.

Alzheimer's disease (AD) is a devastating neurodegenerative condition that poses major challenges to human health. Both amyloid ß (Aß) and metal ions such as aluminium are implicated in the development of AD. By the means of NMR, the interactions of Al3+ with Aß1-28 peptide as well as the Aß1-28 analogues were studied, and the key binding sites of Al3+ in Aß determined. NMR data showed Al3+ interacts with Aß1-28 at the NH and αH of numerous residues by exhibiting upfield shifts. Using Aß analogues where His6, His13 and His14 were individually replaced by alanine residue(s), including Aß H6A, Aß H13A, Aß H14A, and Aß H6,13,14A, the results demonstrated that the histidine residues (His6, His13 and His14) and N-terminal Asp1 were involved in the Al3+ coordination. These findings provide, for the first time, the details of the molecular interaction between Al3+ and Aß, which points to the potential role of Al3+ in Aß aggregation, hence in AD development.

Risk factors of knee osteoarthritis in Bangladeshi adults: a national survey.

BACKGROUND: Knee osteoarthritis was reported as the second most prevalent condition in the national musculoskeletal survey. The purpose of this extended study was to identify risk factors for knee osteoarthritis in Bangladeshi adults. METHODS: This cross-sectional study was conducted in rural and urban areas of Bangladesh using stratified multistage cluster sample of 2000 adults aged 18 years or older recruited at their households. The Modified Community Oriented Program for Control of Rheumatic Disorders (COPCORD) questionnaire was used to collect data. The diagnosis of knee osteoarthritis was made using the decision tree clinical categorization criteria of the American College of Rheumatology. Univariate and multivariate logistic regression analyses were done to identify the risk factors for knee osteoarthritis. RESULTS: A total of 1843 individuals (892 men and 951 women) participated, and 134 had knee osteoarthritis yielding a prevalence of 7.3% (95% confidence interval (CI) 4.9 to 9.6%). The mean (standard deviation) age of the knee osteoarthritis patients was 51.7 (11.2) years. Multivariate logistic regression analysis found a significant association with increasing age (≥38 years OR 8.9, 95% CI 4.8-16.5; ≥58 years OR 13.9, 95% CI 6.9-28.0), low educational level (OR 1.7, 95% CI 1.0-2.7) and overweight (OR 1.9, 95% CI 1.2-2.9) with knee osteoarthritis. Knee osteoarthritis patients had a high likelihood of having work loss preceding 12 months (age and sex-adjusted OR 2.3; 95% CI 1.4-3.8; P < 0.01). CONCLUSIONS: Knee osteoarthritis is a commonly prevalent musculoskeletal problem among Bangladeshi adults having link to work loss. Increasing age, low education and overweight are significant risk factors of knee osteoarthritis.

Feedback regulation of Arid5a and Ppar-γ2 maintains adipose tissue homeostasis.

Immune cells infiltrate adipose tissues and provide a framework to regulate energy homeostasis. However, the precise underlying mechanisms and signaling by which the immune system regulates energy homeostasis in metabolic tissues remain poorly understood. Here, we show that the AT-rich interactive domain 5A (Arid5a), a cytokine-induced nucleic acid binding protein, is important for the maintenance of adipose tissue homeostasis. Long-term deficiency of Arid5a in mice results in adult-onset severe obesity. In contrast, transgenic mice overexpressing Arid5a are highly resistant to high-fat diet-induced obesity. Inhibition of Arid5a facilitates the in vitro differentiation of 3T3-L1 cells and fibroblasts to adipocytes, whereas its induction substantially inhibits their differentiation. Molecular studies reveal that Arid5a represses the transcription of peroxisome proliferator activated receptor gamma 2 (Ppar-γ2) due to which, in the absence of Arid5a, Ppar-γ2 is persistently expressed in fibroblasts. This phenomenon is accompanied by enhanced fatty acid uptake in Arid5a-deficient cells, which shifts metabolic homeostasis toward prolipid metabolism. Furthermore, we show that Arid5a and Ppar-γ2 are dynamically counterregulated by each other, hence maintaining adipogenic homeostasis. Thus, we show that Arid5a is an important negative regulator of energy metabolism and can be a potential target for metabolic disorders.

Dynamically controlled dielectrophoresis using resonant tuning.

Electrically polarizable micro- and nanoparticles and droplets can be trapped using the gradient electric field of electrodes. But the spatial profile of the resultant dielectrophoretic force is fixed once the electrode structure is defined. To change the force profile, entire complex lab-on-a-chip systems must be re-fabricated with modified electrode structures. To overcome this problem, we propose an approach for the dynamic control of the spatial profile of the dielectrophoretic force by interfacing the trap electrodes with a resistor and an inductor to form a resonant resistor-inductor-capacitor (RLC) circuit. Using a dielectrophoretically trapped water droplet suspended in silicone oil, we show that the resonator amplitude, detuning, and linewidth can be continuously varied by changing the supply voltage, supply frequency, and the circuit resistance to obtain the desired trap depth, range, and stiffness. We show that by proper tuning of the resonator, the trap range can be extended without increasing the supply voltage, thus preventing sensitive samples from exposure to high electric fields at the stable trapping position. Such unprecedented dynamic control of dielectrophoretic forces opens avenues for the tunable active manipulation of sensitive biological and biochemical specimen in droplet microfluidic devices used for single-cell and biochemical reaction analysis.

Urinary Continence Outcomes in Classic Bladder Exstrophy: A Long-Term Perspective.

PURPOSE: We investigated surgical approaches to urinary incontinence and long-term continence outcomes after successful bladder reconstruction in a heterogeneous patient population with classic bladder exstrophy. We hypothesized that while most patients will achieve urinary continence after surgery, only a select group will void volitionally per urethra. MATERIALS AND METHODS: An institutional database of 1,323 patients with exstrophy-epispadias complex was reviewed for patients with classic bladder exstrophy who underwent successful bladder closure and a subsequent continence procedure between 1975 and 2017. Procedures included bladder neck reconstruction, bladder neck reconstruction with augmentation cystoplasty or continent catheterizable stoma, and bladder neck closure with continent catheterizable stoma. Cloacal exstrophy, epispadias and variant exstrophy cases were excluded from analysis. Continence at last followup was defined as a dry interval of 3 or more hours without nighttime leakage. Those patients with more than 3 months of followup were assessed. RESULTS: Overall 432 patients underwent successful bladder closure (primary 71.5%, repeat 28.5%) and a urinary continence procedure. At last followup 162 (37%) underwent bladder neck reconstruction, 76 (18%) underwent bladder neck reconstruction with augmentation cystoplasty or continent catheterizable stoma, 173 (40%) underwent bladder neck closure with continent catheterizable stoma and 18 underwent other procedures. Median followup from the first continence procedure was 7.2 years (IQR 2.3-13.7). Continence was assessed in 350 patients. After isolated bladder neck reconstruction 91 of 142 patients were continent (64%, 95% CI 56-72). After bladder neck closure with continent catheterizable stoma 124 of 133 patients evaluated were continent (93%, 95% CI 87-97). CONCLUSIONS: Most patients with classic bladder exstrophy require multiple reconstructive procedures to achieve continence. Only about 25% of patients are expected to void normally per urethra without reliance on catheterization or urinary diversion.

Deciphering the Complex Mineralogy of River Sand Deposits through Clustering and Quantification of Hyperspectral X-Ray Maps.

Alluvial mineral sands rank among the most complex subjects for mineral characterization due to the diverse range of minerals present in the sediments, which may collectively contain a daunting number of elements (>20) in major or minor concentrations (>1 wt%). To comprehensively characterize the phase abundance and chemistry of these complex mineral specimens, a method was developed using hyperspectral x-ray and cathodoluminescence mapping in an electron probe microanalyser (EPMA), coupled with automated cluster analysis and quantitative analysis of clustered x-ray spectra. This method proved successful in identifying and quantifying over 40 phases from mineral sand specimens, including unexpected phases with low modal abundance (<0.1%). The standard-based quantification method measured compositions in agreement with expected stoichiometry, with elemental detection limits in the range of <10­1,000 ppm, depending on phase abundance, and proved reliable even for challenging mineral species, such as the multi-rare earth element (REE) bearing mineral xenotime [(Y,REE)PO4] for which 24 elements were analyzed, including 12 overlapped REEs. The mineral identification procedure was also capable of characterizing mineral groups that exhibit significant compositional variability due to the substitution of multiple elements, such as garnets (Mg, Ca, Fe, Mn, Cr), pyroxenes (Mg, Ca, Fe), and amphiboles (Na, Mg, Ca, Fe, Al).

Arid5a stabilizes OX40 mRNA in murine CD4+ T cells by recognizing a stem-loop structure in its 3'UTR.

AT-rich interactive domain-containing protein 5a (Arid5a) is an RNA-binding protein (RBP) required for autoimmunity via stabilization of interleukin-6 (Il6) and signal transducer and activator of transcription 3 (STAT3) mRNAs. However, the roles of Arid5a in Th17 cells and its association with autoimmunity remain unknown. Here, we show that the levels of Arid5a and OX40 are correlated in CD4+ T cells under Th17 conditions in an IL-6-dependent manner. Lack of Arid5a in T cells reduced OX40 expression levels and repressed IL-17 production in response to OX40 ligation. Arid5a stabilized OX40 mRNA by recognizing the alternative decay element (ADE)-like stem-loop (SL) in the 3' untranslated region (3'UTR). Interestingly, Arid5a impaired the RNA-destabilizing functions of Regnase-1 and Roquin-1 on OX40 ADE-like SL. In EAE, Arid5a-deficient mice exhibited resistance to EAE, with reduced OX40 expression in CD4+ T cells, and the number of CD4+ CD45+ T cells was decreased in CNS. Furthermore, ameliorated EAE was induced by adoptive transfer of Arid5a-/- encephalitogenic CD4+ T cells expressing less OX40 mRNA and producing less IL-17. In conclusion, our findings indicate that the Arid5a/OX40 axis in CD4+ T cells may have important implications in pathogenesis of autoimmune diseases such as EAE.

In-plane near-field optical barrier on a chip.

Nanoparticles trapped on resonant near-field structures engraved on a metallic substrate experience forces due to the engravings, as well as the image-like interaction with the substrate. In the case of normally incident optical excitation, the force due to the substrate is solely perpendicular to its surface. Numerical simulations are presented to demonstrate that under the combined influence of the aforementioned forces, a plasmonic nanoparticle can be repelled from the engraving along the substrate, while attracting it towards the substrate along its normal. This behavior can be achieved over a range of excitation wavelengths of the short wavelength mode of the coupled particle-substrate-trap system. To the best of our knowledge, this is the first illustration of an in-plane near-field optical barrier on a chip. The barrier is stable against resistive heating of the nanoparticle, as well as the induced non-isothermal flow. The wavelength-dependent switch between the proposed in-plane potential barrier and the stable potential well can pave the way for the gated transport of single nanoparticles, while holding them bound to the chip.

Protein kinase CK2 is involved in zinc homeostasis in breast and prostate cancer cells.

The intracellular zinc profiles of breast and prostate cancer cells are diametrically opposed, with hyper-accumulation of zinc in breast cancer, and low level in prostate cancer. This phenomenon is poorly understood. This study employs two breast and two prostate cancer cell lines to investigate the role of protein kinase CK2 in regulating zinc homeostasis. CK2 was targeted by its specific inhibitors 4,5,6,7-tetrabromobenzotriazole (TBB) and CX-4945, and by the specific siRNA against each of the three CK2 genes. The effect of zinc exposure after the above CK2 manipulation was observed by MTT [3-(4,5-dimethyliazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] cell viability assay and confocal microscopy for intracellular zinc level. The results demonstrate that CK2 is involved in regulating zinc homeostasis in breast and prostate cancer cells as both TBB and CX-4945 substantially decreased cell viability upon zinc exposure. siRNA-mediated knockdown of the three CK2 subunits (α, α' and ß) revealed their discrete roles in regulating zinc homeostasis in breast and prostate cancer cells. Knockdown of CK2α' decreased the intracellular zinc level of breast cancer cells and in turn increased the cell viability while the opposite findings were obtained for the prostate cancer cells. Knockdown of CK2ß expression substantially increased the zinc level in breast cancer cell lines whilst decreased the zinc level in prostate cancer cells. Taken together, this study shows that CK2 is involved in zinc homeostasis of breast and prostate cancer cells and opens a new avenue for research on these cancers.

Anatomy of Classic Bladder Exstrophy: MRI Findings and Surgical Correlation.

PURPOSE OF REVIEW: The exstrophy-epispadias complex (EEC) represents a group of congenitally acquired malformations involving the musculoskeletal, gastrointestinal, and genitourinary systems. Classic bladder exstrophy (CBE) is the most common and best studied entity within the EEC. In this review, imaging features of CBE anatomy will be presented with surgical correlation. RECENT FINDINGS: Magnetic resonance imaging (MRI) has emerged as a useful modality for pre- and postnatal assessment of the abdominal wall, pelvic floor, and gastrointestinal and genitourinary systems of children with CBE. The authors' experience supports use of preoperative MRI, in conjunction with navigational software, as a method for identifying complex CBE anatomy. Imaging facilitates surgical approach and improves visualization of complex anatomy, potentially helping to avoid complications. Continued investigation of imaging guidance in CBE repair is needed as surgical techniques improve.

TLR4-induced NF-κB and MAPK signaling regulate the IL-6 mRNA stabilizing protein Arid5a.

The AT-rich interactive domain-containing protein 5a (Arid5a) plays a critical role in autoimmunity by regulating the half-life of Interleukin-6 (IL-6) mRNA. However, the signaling pathways underlying Arid5a-mediated regulation of IL-6 mRNA stability are largely uncharacterized. Here, we found that during the early phase of lipopolysaccharide (LPS) stimulation, NF-κB and an NF-κB-triggered IL-6-positive feedback loop activate Arid5a gene expression, increasing IL-6 expression via stabilization of the IL-6 mRNA. Subsequently, mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1) promotes translocation of AU-rich element RNA-binding protein 1 (AUF-1) from the nucleus to the cytoplasm, where it destabilizes Arid5a mRNA by binding to AU-rich elements in the 3΄ UTR. This results in downregulation of IL-6 mRNA expression. During the late phase of LPS stimulation, p38 MAPK phosphorylates Arid5a and recruits the WW domain containing E3 ubiquitin protein ligase 1 (WWP1) to its complex, which in turn ubiquitinates Arid5a in a K48-linked manner, leading to its degradation. Inhibition of Arid5a phosphorylation and degradation increases production of IL-6 mRNA. Thus, our data demonstrate that LPS-induced NF-κB and MAPK signaling are required to control the regulation of the IL-6 mRNA stabilizing molecule Arid5a. This study therefore substantially increases our understanding of the mechanisms by which IL-6 is regulated.

Arid5a exacerbates IFN-γ-mediated septic shock by stabilizing T-bet mRNA.

Adenine-thymine (AT)-rich interactive domain containing protein 5a (Arid5a) is an RNA-binding protein that has been shown to play an important immune regulatory function via the stabilization of IL-6 and STAT3 mRNA. However, the role of Arid5a in the overwhelming and uncontrolled immune response that leads to septic shock is unknown. Here, we report that Arid5a-deficient mice are highly resistant to lipopolysaccharide (LPS)-induced endotoxic shock and secrete lower levels of major proinflammatory cytokines, including IFN-γ, IL-6, and TNF-α, than WT mice in response to LPS. Arid5a deficiency resulted in decreased levels of IFN-γ under Th1 cell conditions, in which T-box expressed in T cells (T-bet) mRNA expression was inhibited. Arid5a bound to the conserved stem loop structure of the 3'UTR of T-bet and stabilized its mRNA. Arid5a-deficient mice were also resistant to Propionibacterium acnes-primed LPS injection, which is considered to be a T-cell-mediated IFN-γ dependent endotoxic shock mouse model. Thus, regulation of IFN-γ by Arid5a via the stabilization of T-bet mRNA in Th1 cells contributes to the development of septic shock in mice. In addition, our previous study suggests that Arid5a control the IL-6 level in vivo in response to LPS by stabilization of IL-6 mRNA. We also observed that neutralization of IFN-γ and IL-6 significantly recovered the mice from endotoxic shock. Taken together, we conclude that Arid5a regulates the augmentation of IL-6 and IFN-γ in response to LPS, which possibly works synergistically for amplification of various other cytokines that ultimately cause the development of septic shock in mice.

Arid5a-deficient mice are highly resistant to bleomycin-induced lung injury.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are among the major causes of death worldwide due to acute inflammation in the lung. AT-rich interactive domain-containing 5a (Arid5a) is an RNA-binding protein involved in inflammatory autoimmune disease through post-transcriptional control of Il6, Stat3 and Tbx21 gene expression. We found that Arid5a-deficient mice were highly refractory to bleomycin (BLM)-induced lethality. Arid5a deficiency suppressed lung pathology, cytokine production (especially, IL-6), and clinical symptoms in BLM-treated mice. Production of reactive oxygen species (ROS) in response to BLM-induced cellular damage was inhibited in Arid5a-deficient mice, potentially affecting the level of oxidized 1-palmitoyl-2-arachidonoyl-phosphaticylcholine (OxPAPC) production. OxPAPC, which is supposed to be a TLR4/TLR2 ligand, stimulated expression of the Arid5a and Il6 genes. Thus, reduction of ROS production in Arid5a-deficient mice could mitigate OxPAPC production, which in turn decreases IL-6 production in vivo due to dysregulated post-transcriptional regulation by loss of Arid5a. Therefore, the control of Arid5a expression represents a potential therapeutic target for treatment of ALI and ARDS.

Synthesis of novel benzimidazole acrylonitriles for inhibition of Plasmodium falciparum growth by dual target inhibition.

Antimalarial drug resistance has emerged as a threat for treating malaria, generating a need to design and develop newer, more efficient antimalarial agents. This research aimed to identify novel leads as antimalarials. Dual receptor mechanism could be a good strategy to combat developing drug resistance. A series of benzimidazole acrylonitriles containing 18 compounds were designed, synthesized and evaluated for cytotoxicity, heme binding, ferriprotoporphyrin IX biomineralisation inhibition, and falcipain-2 enzyme assay. Furthermore, in silico docking and MD simulation studies were also performed.The tests revealed quite encouraging results. Three compounds, viz. R-01 (0.69 µM), R-04 (1.60 µM), and R-08 (1.61 µM), were found to have high antimalarial activity. These compounds were found to be in bearable cytotoxicity limits and their biological assay suggested that they had inhibitory activity against falcipain-2 and hemozoin formation. The docking revealed the binding mode of benzimidazole acrylonitrile derivatives and MD simulation studies revealed that the protein-ligand complex was stable. The agents exhibit good hemozoin formation inhibition activity and, hence, may be utilized as leads to design a newer drug class to overcome the drug resistance of hemozoin formation inhibitors such as chloroquine.