Search

Acute respiratory distress syndrome (ARDS) is one of the major cause of mortality in COVID-19 patients, due to limited therapeutic options. This prompted us to explore natural sources to mitigate this condition. Gymnema sylvestre (GS) is an ancient medicinal plant known to have various therapeutic effects. In this investigation, Gymnema sylvestre hydroalcoholic extract (HAEGS) was examined against lipopolysaccharide (LPS) induced lung injury and ARDS in in vitro and in vivo models. UHPLC-HRMS/GC-MS was employed for characterizing the HAEGS and identified several active derivatives including gymnemic acid, gymnemasaponins, gymnemoside, gymnemasin, quercetin, and long fatty acids. Gene expression by RTqPCR and DCFDA analysis by flow-cytometry revealed that several inflammatory cytokine/chemokine, cell injury markers, and reactive-oxygen-species (ROS) levels were highly upregulated in LPS control and were significantly reduced upon HAEGS treatment. Consistent with the in vitro studies, we found that in LPS induced ARDS model, pre-treatment with HAEGS significantly suppressed the LPS-induced elevation of inflammatory cell infiltrations, cytokine/chemokine marker expression, ROS levels, and lung injury in a dose dependent manner. Further mechanistic studies suggested that the HAEGS ameliorates the ARDS through the NF-κB/MAPK signaling pathway. Additional fractionation results revealed that fraction-6 which has the exclusive composition of gymnemic acid derivatives showed anti-inflammatory effects which is similar to the HAEGS. Overall, HAEGS significantly mitigated the LPS-induced lung injury and ARDS by targeting NF-κB/MAPK signaling pathway. Thus, our work unravels the protective role of HAEGS for the first time in managing ARDS.

Background The progression of chronic pancreatitis (CP), an inflammatory disease of the pancreas, causes pancreatic stones to form within the pancreatic ductal lumen/parenchyma, which occurs via protein plug formation. Pain is the most common symptom that necessitates clinical attention, and pain relief is the therapeutic goal for these patients. Endoscopic therapy and surgery are complimentary forms of therapy for pain relief. This study was envisaged to clarify the mechanism by which protein plug/soft stones form in pancreatic ducts prior to undergoing calcification. Methods Protein plugs were obtained from twenty CP patients undergoing therapeutic ERCP for stone removal. Pancreatic juice was obtained from five CP patients without stones. Proteins were isolated by TCA/acetone precipitation, SDS PAGE and 2-D gel electrophoresis to determine the protein profile. Protein spots from the 2-D gel were excised and subjected to matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) for identification. The effect of altered pH and elevated concentrations of trypsin on pancreatic juice protein was assessed by SDS‒PAGE to determine the protein profile. Differentially expressed protein bands were excised and subjected to MALDI-TOF. In silico analysis was performed by docking lithostathine with the calcite molecule using AutoDock Vina and PyMOL to clarify their interaction during stone formation. Results Twenty-three and twenty-nine spots from 2D gels of protein plugs and pancreatic juice, respectively, revealed that lithostathine (Reg1A) was the only protein in the protein plugs, whereas digestive enzymes and lithostathine were identified in pancreatic juice. Altered pH levels and increased trypsin concentrations in the pancreatic juice caused a protein to degrade via an unknown mechanism, and this protein was identified as chymotrypsin C (CTRC) by MALDI-TOF. Docking studies showed that the binding affinity of calcite was higher with the cleaved lithostathine, explaining the deposition of calcium that was observed around the protein plugs after calcified stones were formed through precipitation. Conclusion Our results suggest that chymotrypsin C (CTRC) is degraded in an acidic environment, leading to the precipitation of lithostathine in the ductal lumen. Graphical Abstract

International audience; A low-cost synthetic 2-cyano-3-(2-thienyl)acrylic acid (CTA) is developed as a new MALDI matrix for the analysis of various classes of compounds such as lipids (e.g., fatty acids), peptides, proteins, saccharides, natural products (i.e., iridoids), PEGs, and organometallics in the positive-ion mode. The difficulty in the analysis of high molecular mass PEGs was overcome by using CTA as matrix even at low concentrations. Both high molecular mass proteins and peptides were successfully analyzed using CTA. The mass spectra of all of the studied analytes with CTA showed high signal-to-noise (S/N) ratios and spectral resolutions when compared to other conventional matrices such as SA, DHB, DT, and HCCA. However, in the case of peptide analysis with CTA, the resulting mass spectra are found to be similar to that of the well-established HCCA matrix. On the basis of the physicochemical properties of the analytes, the CTA works as a proton/cation or electron-transfer matrix. It proves that the CTA can be used as a common matrix for the analysis of majority classes of analytes instead of using a specific matrix for the particular class of analytes. Further, the CTA provides an advantage in the analysis of unknown samples as it rules out ambiguity in the selection of particular matrix and it may also offer a complete profile of the tissue surface in the MALDI-imaging experiments.

Indacaterol (IND), 5-[2-[(5,6-Diethyl-2,3-dihydro-1H-inden-2-yl)amino]-1-hydroxyethyl]-8-hydroxyquinolin-2(1H)-one, is an active pharmaceutical ingredient (API) which is used to treat chronic obstructive pulmonary disease (COPD). We followed the International Council for Harmonization (ICH) guide lines to study the degradation behavior of IND under various stress conditions. Stressed degradation of the drug was performed under hydrolytic (alkaline, acidic and neutral), photolytic, oxidative and thermal conditions. Identification and characterization of IND and its forced degradation products (DPs) were demonstrated by using LC-HRMS and MS/MS method. A total of three DPs (DP1-DP3) were identified and characterized. The IND was found to be stable under photolytic, oxidative and thermal conditions, whereas it produced three DPs in acidic, basic and neutral hydrolytic stress conditions.

Supplemental material, sj-pdf-1-ems-10.1177_1469066720971550 for Identification and characterization of degradation products of indacaterol using liquid chromatography/mass spectrometry by Naga Veera Yerra, S Babu Dadinaboyina, LSSN Vigjna Abbaraju, MVN Kumar Talluri and Jagadeshwar Reddy Thota in European Journal of Mass Spectrometry

We earlier found that F6 fraction of human filaria Brugia malayi cross-reacted with sera of Leishmania donovani infected hamsters and immunization with F6 inhibited both filarial and leishmanial infections. In the present study, we identified a 52.9-93.6 kDa fraction (Ld1) of L. donovani that cross-reacted with sera of B. malayi infected animals and investigated effect of Ld1 on filarial infection. Immunization of BALB/c mice with Ld1 facilitated B. malayi infection with remarkable increase in parasite burden. Facilitation of filarial infection was associated with downregulated cell proliferation, IL-5, IL-13, IFN-γ, TNF-α, and IL-2 levels and upregulated IL-4 and TGF-β. Ld1 exposure also suppressed MHC class-I, MHC class-II, and FcεR1 expression, and phagocytosis in naive mouse macrophages, and CD4+, CD8+, and CD19+ cell population in mouse spleen. Two-dimensional electrophoresis and matrix-assisted laser desorption ionization-time of flight-mass spectrometry revealed eight proteins in Ld1: putative heat shock protein (HSP) 70-related protein 1, HSP70 mitochondrial precursor, alanine aminotransferase, 2,3-bisphosphoglycerate-independent phosphoglycerate mutase, protein disulfide isomerase, putative ATPase beta subunit, trypanothione reductase, and a hypothetical protein. HSP70 protein mitochondrial precursor and trypanothione reductase showed homology with Trypanosoma cruzi and L. donovani, respectively, and the rest 6 proteins including hypothetical protein bear homology with L. infantum. In conclusion, the present study for the first time shows that immunization with filarial cross-reactive Ld1 fraction of L. donovani facilitates filarial infection by modulating Th1 and Th2 responses. Ld1 molecules may therefore facilitate filarial infection in filaria-leishmania co-infection.

The objective of the present study was to identify the proteome pattern, isolate and study the functions of selective proteins from Ferula asafoetida root exudate using chromatographic techniques. The root exudate proteins were fractionated using ion-exchange and gel filtration chromatography. A range of bioactive protein fractions were then separated in sufficient quantity which is the focus of this study. Based on studies, here we report three main proteins with molecular weights 14kDa, 27kDa, and 39kDa. The biological and pharmacological activities of both purified and unpurified proteins obtained were extensively studied to understand their significance. The study revelaed that 27kDa protein interestingly stabilized trypsin activity in 24h of time and retained about 64% of the enzyme activity. Analyses confirmed 40°C and pH 8.0 are the optimum temperature and pH respectively. The 39kDa protein remarkably increased the activity of chymotrypsin and the 14kDa protein showed anti-bacterial activity against Pseudomonas aeruginosa. Invariably all of the three purified proteins showed enhanced anti-oxidant activity. In conclusion, results here obtained suggested that the primary metabolites (proteins) in asafoetida are mainly responsible for its versatile biological and pharmacological activities.

Rationale Stress testing of a drug candidate is an important step in the drug discovery and development process. The presence of degradation products in a drug affects the quality as well as the safety and efficacy of drug formulation. Hence, it is essential to develop an efficient analytical method which could be useful for the separation, identification and characterization of all possible degradation products (DPs) of a drug. Macitentan (MT) is an endothelin receptor antagonist (ERA) drug used to treat high blood pressure in the lungs. Comprehensive stress testing of MT was carried out as per ICH guidelines to understand the degradation profile of the drug. Methods MT was subjected to various stress conditions such as acidic, basic, neutral hydrolysis, oxidation, photolysis and thermal conditions; and the resulting degradation products were investigated using liquid chromatography/diode-array detection/electrospray ionization high-resolution mass spectrometry (LC/DAD/ESI-HRMS) and tandem mass spectrometry (MS/MS) techniques. An efficient and simple ultra-high-performance liquid chromatography (UHPLC) method has been developed using an Accucore C18 column (4.6 × 150 mm, 2.6 μm) using a gradient elution of 5 mM ammonium formate and acetonitrile as mobile phases. Results MT was found to degrade under acid and base hydrolysis stress conditions; whereas it was stable under oxidation, neutral hydrolysis, thermal and photolytic conditions. MT formed nine DPs (DP1 to DP9) and one DP (DP10) under acidic and basic hydrolytic conditions, respectively. All the degradation products (DP1 to DP10) were identified and characterized by LC/MS/MS in positive ion mode with accurate mass measurements. Conclusions MT was found to be labile under hydrolytic conditions. The structures of the DPs were characterized by appropriate mechanisms. The proposed method can be effectively used for the characterization of MT and its DPs.

// Isha Kapoor 1 , Jitendra Kanaujiya 1 , Yogesh Kumar 1 , Jagadeshwar Reddy Thota 3 , Madan L.B. Bhatt 2 , Naibedya Chattopadhyay 4 , Sabyasachi Sanyal 1 and Arun Kumar Trivedi 1 1 Biochemistry Division, CSIR-Central Drug Research Institute, Lucknow, UP, India 2 Department of Radiotherapy, King George’s Medical University, Lucknow, UP, India 3 SAIF Division, CSIR-Central Drug Research Institute, Lucknow, UP, India 4 Division of Endocrinology and Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute (CSIR-CDRI), Lucknow, UP, India Correspondence to: Arun Kumar Trivedi, email: // Keywords : MNT, E6AP, ATRA, mass spectrometry, APL Received : May 10, 2015 Accepted : September 30, 2015 Published : October 25, 2015 Abstract Perturbed stability of regulatory proteins is a major cause of transformations leading to cancer, including several leukemia subtypes. Here, for the first time we demonstrate that E6-associated protein (E6AP), an E3 ubiquitin ligase negatively targets MAX binding protein MNT for ubiquitin-mediated proteasome degradation and impedes ATRA mediated myeloid cell differentiation. MNT is a member of the Myc/Max/Mad network of transcription factor that regulates cell proliferation, differentiation, cellular transformation and tumorigenesis. Wild-type E6AP promoted proteasome dependent degradation of MNT, while catalytically inactive E6AP having cysteine replaced with alanine at amino-acid 843 position (E6APC843A) rather stabilized it. Further, these proteins physically associated with each other both in non-myeloid (HEK293T) and myeloid cells. MNT overexpression induced G0-G1 growth arrest and promoted myeloid differentiation while its knockdown mitigated even ATRA induced differentiation suggesting MNT to be crucial for myeloid differentiation. We further showed that ATRA inhibited E6AP and stabilized MNT expression by protecting it from E6AP mediated ubiquitin-proteasome degradation. Notably, E6AP knockdown in HL60 cells restored MNT expression and promoted myeloid differentiation. Taken together, our data demonstrated that E6AP negatively regulates granulocytic differentiation by targeting MNT for degradation which is required for growth arrest and subsequent myeloid differentiation by various differentiation inducing agents.

Mirabegron is a novel beta-3 adrenergic receptor agonist in the treatment of overactive bladder disorder. The drug was subjected to hydrolytic, photolytic, thermal and oxidative stress conditions as per the International Conference on Harmonization guidelines (ICH) Q1A (R2) to understand the degradation profile of the drug. The safety of the drug may be affected by degradation products present in the drug. As a result, identification and characterization of degradation products has become very important in drug development processes. In this study, a simple, rapid, precise and accurate ultra performance liquid chromatography (UPLC-PDA) method has been developed on a Waters CSH C18 column (100 mm × 2.1 mm, 1.7 μm) using gradient elution of ammonium acetate (10 mM, pH 5) and acetonitrile as mobile phase. Mirabegron was found to degrade under hydrolytic and oxidative stress conditions while it was stable under thermal and photolytic conditions. A total of seven degradation products were characterized by UPLC-MS/MS in positive ion mode, combined with accurate mass measurements. The proposed structures of the degradation products have been rationalized by appropriate mechanisms. Additionally, in silico toxicity was predicted for all degradant products by using TOPKAT and DEREK softwares to enhance the safety of the drug.

Rationale Iloperidone (ILOP) is atypical antipsychotic drug used for the treatment of schizophrenia and related psychotic disorders. Comprehensive stress testing of ILOP drug was carried out as per ICH guidelines to understand the degradation profile of the drug. The presence of degradation products in a drug affects not only the quality, but also the safety and efficacy of drug formulation. Thus, it is essential to develop an efficient analytical method which could be useful for the separation, identification and characterization of all possible degradation products of ILOP. Methods ILOP was subjected to various stress conditions such as acidic, basic, neutral hydrolysis, oxidation, photolysis and thermal conditions; and the resulting degradation products were investigated using LC-PDA-HRMS and MS/MS. An efficient and simple ultra-high performance liquid chromatography (UHPLC) method has been developed on Acquity UPLC® BEH C18 (2.1 × 100mm, 1.7μm) column using gradient elution of heptafluoro butyric acid ( 0.1% HFBA) and acetonitrile as mobile phase. Results The ILOP was found to degrade under acid, base hydrolysis and oxidative stress conditions; whereas it was stable under neutral hydrolysis, thermal and photolytic conditions. A total of seven degradation products (DP1 to DP7) were identified and characterized by LC-MS/MS in positive ion mode with accurate mass measurements. The hydrolytic degradation under acidic and basic conditions produced two DPs (DP1 and DP2) and four DPs (DP4 to DP7) respectively; whereas DP3 was formed under oxidative conditions. In silico toxicity predictions showed higher probability values for DP4, DP6 and DP7, which indicates these DPs have a potential to mutate DNA. Conclusions ILOP was found to be labile under hydrolytic and oxidative conditions. The structures of the degradation products were rationalized by appropriate mechanisms. The proposed method can be effectively used for the determination and detection of ILOP and its degradation products.

Nitric oxide (NO) mediated mechanisms have been implicated in killing of some life-stages of Brugia malayi/Wuchereria bancrofti and protect the host through type 1 responses and IFN-γ stimulated toxic mediators' release. However, the identity of NO stimulating molecules of the parasites is not known. Three predominantly NO-stimulating SDS-PAGE resolved fractions F8 (45.24-48.64 kDa), F11 (33.44-38.44 kDa) and F12 (28.44-33.44 kDa) from B. malayi were identified and their proteins were analyzed by 2-DE and MALDI-TOF/TOF. Tropomyosin, calponin and de novo peptides were identified by 2-DE and MALDI-TOF/TOF in F8 and immunization with F8 conferred most significant protection against L3-initiated infection in Mastomys coucha. Immunized animals showed upregulated F8-induced NO, IFN-γ, TNF-α, IL-1β, IL-10, TGF-β release, cellular proliferative responses and specific IgG and IgG1. Anti-IFN-γ, anti-TNF-α, and anti-IL-1β significantly reduced F8-mediated NO generation and iNOS induction at protein levels. Anti-IFN-γ treated cells showed maximum reduction (>74%) in NO generation suggesting a predominant role of IFN-γ in iNOS induction. In conclusion, the findings suggest that F8 which contains tropomyosin, calponin and de novo peptides protects the host via IFN-γ mediated iNOS induction and may hold promise as vaccine candidate(s). This is also the first report of identification of tropomyosin and calponin in B. malayi.