10-(6-Plastoquinonyl) decyltriphenylphosphonium imparts anti-colitogenic protection through recovery of mitochondrial dysfunction in ulcerated murine colon: Implications in ulcerative colitis.

AIMS: To elucidate the impact of 10-(6-plastoquinonyl) decyltriphenylphosphonium (SkQ1) as an anti-colitogenic agent for maintenance of colon epithelial tract in ulcerated mice through recovery of mitochondrial dysfunction and mitochondrial stress by virtue of its free radical scavenging properties. MAIN METHODS: DSS induced ulcerated BALB/c mice were treated with SkQ1 for 14 days @ 30 nmol/kg/body wt./day/mice. Post-treatment, isolated colonic mitochondria were utilized for spectrophotometric and spectrofluorometric biochemical analysis of various mitochondrial functional variables including individual mitochondrial respiratory enzyme complexes. Confocal microscopy was utilized for measuring mitochondrial membrane potential in vivo. ELISA technique was adapted for measuring colonic nitrite and 3-nitrotyrosine (3-NT) content. Finally in vitro cell line study was carried out to substantiate in vivo findings and elucidate the involvement of free radicals in UC using antioxidant/free radical scavenging regimen. KEY FINDINGS: Treatment with SkQ1 in vivo reduced histopathological severity of colitis, induced recovery of mitochondrial respiratory complex activities and associated functional variables, improved oxidative stress indices and normalized mitochondrial cardiolipin content. Importantly, SkQ1 lowered nitrite concentration and 3-nitrotyrosine formation in vivo. In vitro SkQ1 restored mitochondrial functions wherein the efficacy of SkQ1 proved equal or better compared to SOD and DMSO indicating predominant involvement of O2- and OH in UC. However, NO and ONOO- also seemed to play a secondary role as MEG and L-NAME provided lesser protection as compared to SOD and DMSO. SIGNIFICANCE: SkQ1 can be considered as a potent anti-colitogenic agent by virtue of its free radical scavenging properties in treating UC.

Fabrication and Therapeutic Process of a Green Silver-Nanoparticle-Embedded Mucilage Microsphere for Pathogenic-Bacteria-Infected Second-Degree Burn and Excision Wounds.

Multidrug-resistant bacteria are a serious problem in biomedical applications that decrease the wound healing process and increase the mortality rate. Therefore, in this study, we have prepared a green-synthesized silver-nanoparticle-encapsulated mucilage microsphere (HMMS@GSNP) from Hibiscus rosa sinensis leaves and applied it to pathogen-infected burn and excision wounds. Biophysical properties like size, polydispersity index, absorbance capacity, and drug release were measured by different techniques like field-emission scanning electron microscopy, dynamic light scattering, swelling ratio, etc. The strong antibacterial activity of a HMMS@GSNP microsphere was measured by minimum inhibitory concentration assay, minimum bactericidal concentration assay, and agar well diffusion methods. The HMMS@GSNP microsphere enhanced the cell viability, cell proliferation, migration, antioxidant, and antiinflammation activity compared to untreated GSNP and HMMS, as quantified by MTT assay, BrdU assay, scratch wound assay, reactive oxygen species scavenging assay, and Western blot analysis, respectively. In the in vivo experiment, we used a methicillin-resistant Staphylococcus aureus bacteria-infected, burn-and-excision-wound-created male BALB/c mice model. The HMMS@GSNP-treated burn-and-excision-wound-infected mice showed significant results compared to other groups (untreated, Silverex Ionic Gel, AgNO3, HMMS, and GSNP), and the mice tissues were utilized for bacteria count, immunoblot analysis, histological studies, and real-time polymerase chain reaction. Thus, the HMM@GSNP microsphere is an excellent therapeutic material that can be used as a topical agent for the management of chronic wound therapy.

Facile process ofHibiscusmucilage polymer formulation usingHibiscus rosa-sinensisleaves to treat second-degree burn and excision wounds.

Mucilage is a sticky substance found in various plants and microorganisms and is made up of proteins and polysaccharides. Mucilage fromHibiscus rosa sinensisisis a complex polysaccharide traditionally used to treat different skin diseases. In our study, we fabricated mucilage polymer fromHibiscus rosa sinensisleaves and evaluated its potential application in second-degree burns and excision wounds. The physical properties of Hibiscus mucilage (HM) polymer were demonstrated by using Ultraviolet-visible absorption spectroscopy, x-ray diffraction, Fourier transform infrared spectroscopy, dynamic light scattering, Scanning electron microscopy, Brunauer-Emmett-Tellerand, Swelling ratio. The human cell lines WI-38, and HaCaT have been used forin-vitroexperiments like MTT, scratch wound, BrdU, ROS scavenging assays, and western blot analysis. The results of the MTT, scratch-wound, and BrdU assay indicated that the HM polymer is nontoxic in nature and also enhances both the properties of cellular migration and proliferation, respectively. On the other hand, the result of the ROS scavenging assay suggested that HM polymer enhances the antioxidant activity of cells while the western blot analysis designated that the HM polymer treatment caused downregulation of the pro-inflammatory cytokine IFN-γand upregulation of the pAkt (Serine 473) protein, and TGF-ß1 signaling pathway. Therefore, allin-vitroexperimental studies recommended that HM polymer is biocompatible and has antioxidant and anti-inflammatory effects. In thein vivoexperiment, second-degree burns and excision wounds were created on the dorsal surface of male BALB/c mice. After the sixth day of HM polymer treatment have developed new tissue, hair follicles, blood vessels,α-SMA, and Collagen type-1 fiber on the burn and excision wound area while the 11th day of HM polymer treatment cured the wound area significantly. Therefore, it could be contemplated that HM polymer is a potential agent for treating different wounds in the near future.

Contrasting effects of molecular crowding on the membrane-perturbing and chaperone-like activities of major bovine seminal plasma protein, PDC-109.

Crowded environments inside cells and biological fluids greatly affect protein stability and activity. PDC-109, a polydisperse oligomeric protein of the bovine seminal plasma selectively binds choline phospholipids on the sperm cell surface and causes membrane destabilization and lipid efflux, leading to acrosome reaction. PDC-109 also exhibits chaperone-like activity (CLA) and protects client proteins against various kinds of stress, such as high temperature and low pH. In the present work, we have investigated the effect of molecular crowding on these two different activities of PDC-109 employing Dextran 70 (D70) - a widely used polymeric dextran - as the crowding agent. The results obtained show that presence of D70 markedly increases membrane destabilization by PDC-109. Isothermal titration calorimetric studies revealed that under crowded condition the binding affinity of PDC-109 for choline phospholipids increases approximately 3-fold, which could in turn facilitate membrane destabilization. In contrast, under identical conditions, its CLA was reduced significantly. The decreased CLA could be correlated to reduced surface hydrophobicity, which was due to stabilization of the protein oligomers. These results establish that molecular crowding exhibits contrasting effects on two different functional activities of PDC-109 and highlight the importance of microenvironment of proteins in modulating their functional activities.

Topical effect of polyherbal flowers extract on xanthan gum hydrogel patch-induced wound healing activity in human cell lines and male BALB/c mice.

Wound or injury is a breakdown in the skin's protective function as well as damage to the normal tissues. Wound healing is a dynamic and complex phenomenon of replacing injured skin or body tissues. In ancient times theCalendula officinalisandHibiscus rosa-sinensisflowers were extensively used by the tribal communities as herbal medicine for various complications including wound healing. But loading and delivery of such herbal medicines are challenging because it maintains their molecular structure against temperature, moisture, and other ambient factors. This study has fabricated xanthan gum (XG) hydrogel through a facile process and encapsulatedC. officinalisandH. rosa-sinensisflower extract. The resulting hydrogel was characterized by different physical methods like x-ray diffractometer, UV-vis spectroscopy, Fourier transform infrared spectroscopy, SEM, dynamic light scattering, electronkinetic potential in colloidal systems (ZETA) potential, thermogravimetric differential thermal analysis (TGA-DTA), etc. The polyherbal extract was phytochemically screened and observed that flavonoids, alkaloids, terpenoids, tannins, saponins, anthraquinones, glycosides, amino acids, and a few percentages of reducing sugar were present in the polyherbal extract. Polyherbal extract encapsulated XG hydrogel (X@C-H) significantly enhanced the proliferation of fibroblast and keratinocyte cell lines in comparison to the bare excipient treated cells as determined by 3-(4, 5-dimethylthiazol-2-Yl)-2, 5-diphenyltetrazolium bromide assay. Also, the proliferation of these cells was confirmed by BrdU assay and enhanced expression of pAkt. In anin-vivostudy, wound healing activity of BALB/c mice was carried out and we observed that X@C-H hydrogel showed significant result compared to the other groups (untreated, X, X@C, X@H). Henceforth, we conclude that this synthesized biocompatible hydrogel could emerge as a promising carrier of more than one herbal excipients.

In silico analysis of single nucleotide polymorphism (rs34377097) of TBXA2R gene and pollen induced bronchial asthma susceptibility in West Bengal population, India.

Introduction: Prevalence of asthma is increasing steadily among general population in developing countries over past two decades. One of the causative agents of broncho-constriction in asthma is thromboxane A2 receptor (TBXA2R). However few studies of TBXA2R polymorphism were performed so far. The present study aimed to assess potential association of TBXA2R rs34377097 polymorphism causing missense substitution of Arginine to Leucine (R60L) among 482 patients diagnosed with pollen-induced asthma and 122 control participants from West Bengal, India. Also we performed in-silico analysis of mutated TBXA2R protein (R60L) using homology modeling. Methods: Clinical parameters like Forced expiratory volume in 1 second (FEV1), FEV1/Forced vital capacity (FVC) and Peak expiratory flow rate (PEFR) were assessed using spirometry. Patients' sensitivity was measured by skin prick test (SPT) against 16 pollen allergens. Polymerase chain reaction-based Restriction fragment length polymorphism was done for genotyping. Structural model of wild type and homology model of polymorphic TBXA2R was generated using AlphaFold2 and MODELLER respectively. Electrostatic surface potential was calculated using APBS plugin in PyMol. Results: Genotype frequencies differed significantly between the study groups (P=0.03). There was no significant deviation from Hardy-Weinberg equilibrium in control population (χ2=1.56). Asthmatic patients have significantly higher frequency of rs34377097TT genotype than control subjects (P=0.03). SPT of patients showed maximum sensitivity in A. indica (87.68%) followed by C. nusifera (83.29%) and C. pulcherima (74.94%). Significant difference existed for pollen sensitivity in adolescent and young adult (P=0.01) and between young and old adult (P=0.0003). Significant negative correlation was found between FEV1/FVC ratio and intensity of SPT reactions (P<0.0001). Significant association of FEV1, FEV1/FVC and PEFR was observed with pollen-induced asthma. Furthermore, risk allele T was found to be clinically correlated with lower FEV1/FVC ratio (P=0.015) in patients. Our data showed R60L polymorphism, which was conserved across mammals, significantly reduced positive electrostatic charge of polymorphic protein in cytoplasmic domain thus altered downstream pathway and induced asthma response. Discussion: The present in-silico study is the first one to report association of TBXA2R rs34377097 polymorphism in an Indian population. It may be used as prognostic marker of clinical response to asthma in West Bengal and possible target of therapeutics in future.

Multifaceted entrancing role of glucose and its analogue, 2-deoxy-D-glucose in cancer cell proliferation, inflammation, and virus infection.

Chronic exposure to high glucose inside the human body helps in the progression of cancer by activating various signaling pathways including PI3K, Akt, mTOR, Ras, Raf, MAPK, and PKC. Hyperglycemia induces ROS and AGE production and decreases the functional activities of the cellular antioxidant system. By downregulating the prolyl hydroxylase, it stabilizes HIF-α leading to EMT-induced cancer progression and inhibition of apoptosis. High glucose level increases inflammation by creating a pro-inflammatory environment through the production of certain pro-inflammatory mediators (cytokines, chemokines, leukotrienes), and by influencing the recruitment of immune cells, leukocytes in the inflamed region. High glucose impairs the immune response and dysregulates ROS formation through the alteration in ETC and glutaminolysis which makes hyperglycemic patients more susceptible to viral infection. 2-DG is a modified form of D-glucose, that shows anticancer, anti-inflammatory, and anti-viral effects. It enters the cells through GLUT transporters and is converted into 2-deoxy-D-glucose-6-phosphate with the help of hexokinase. It inhibits the glycolysis, the TCA cycle, and the pentose phosphate pathway leading to ATP depletion. By downregulating glucose uptake and energy (ATP) production it halts various pathways responsible for cancer progression. It promotes the formation of anti-inflammatory mediators, and macrophage polarization, and also modulates immune function, which decreases inflammation. 2-DG inhibits PI3K/Akt/mTOR and upregulates the AMPK pathway, causing activation of the SIRT-4 gene that reduces lipogenesis, glucose uptake, nucleotide formation, and alters viral replication thus reducing the chances of infection.

Melatonin ameliorates lipopolysaccharide induced brain inflammation through modulation of oxidative status and diminution of cytokine rush in Danio rerio.

Lipopolysaccharide (LPS) is known to induce inflammation and immunonomodulation in a piscine model of Danio rerio. Present study aimed to explore the ability of melatonin in attenuating LPS-induced oxidative damages using this model. In LPS-exposed fish, activation of stress marker MDA was observed in brain with corresponding augmentation of multiple pro-inflammatory cytokines (IL1ß, IL6, IL10 and TNFα). In addition, it also showed marked increase in the levels of heat shock factor (HSF) and heat shock proteins (HSPs) in association with transcription factors (NF-kB and NRF2) and mitogen-activated protein kinases (MAPKs). The changes in the levels of these mediators are highly correlated with the induction of pro-inflammatory cytokines. In melatonin-treated fishes, significant amelioration of oxidative stress was observed with reduced levels of MDA and pro-inflammatory cytokines. Melatonin also modulated expression of HSPs that facilitated the brain to overcome inflammation-induced stress by directly initiating NFkB/NRF2 translocation. In summary, melatonin effectively functions to reduce stress induced inflammatory signalling through modulation of oxidative stress and protects the brain from the neuropathological insult.

Biocompatible Carbon Dot Decorated α-FeOOH Nanohybrid for an Effective Fluorometric Sensing of Cr (VI) in Wastewater and Living Cells.

This article reports the fluorometric detection of toxic hexavalent chromium Cr (VI)) in wastewater and Cr (VI) contaminated living cells using in-situ grown carbon quantum dots into the goethite (α-FeOOH) nano-matrix. The synthesized nano-hybrid shows enormous potential in determining the chromium contamination levels in various types of water samples. This selective fluorometric probe is enormously sensitive (LOD 81 nM) toward hexavalent chromium, which makes it a dedicated chromium sensor. Moreover, the sensing mechanism has been assessed using Stern-Volmer's equation and fluorescence lifetime experiments showing the simultaneous occurrence of photoinduced electron transfer and the inner filter effect. This chromium sensor has also been employed to assess the contamination level in real-life industrial wastewater. The performance of this probe in a real-life wastewater sample is quite commendable. Further, this biocompatible fluorometric probe has been used to demonstrate the in-vitro sensing of Cr (VI) in HeLa cells. The rapid detection mechanism of hexavalent chromium in living cells has been validated using theoretical docking simulations. Henceforth, this fluorometric sensor material could open new avenues not only in wastewater monitoring but also in biomedical applications.

Molecular dissection of cellular response of pancreatic islet cells to Bisphenol-A (BPA): A comprehensive review.

Bisphenol A (BPA) is an endocrine disrupting chemical which poses great concern because of its high proportionate industrial production, omnipresent human exposure and budding toxic consequences in human. A plethora of previous studies has connected BPA to a variety of negative health outcomes and diabetes mellitus is among the first bencher. However, there is disagreement over the degree of toxic effects generated by low and high doses of BPA and critical period of exposure. Furthermore, the safe level of BPA determined by classical toxicological studies does not protect pancreatic islet cells from low dose effects of BPA. Thus, the extremities of toxic effects on pancreatic islets associated with BPA exposure are complicated and contentious. In this review, we highlighted different cellular and molecular pathways targeted by BPA to mediate its action on pancreatic islets with consideration of both low and high dose effects. Besides estrogen receptor α and ß, BPA also uses non canonical membrane bound estrogen receptor and G-protein coupled estrogen receptor to confer its toxic effects. In doing so, BPA modulates ion channels, and transcription factors; causes aggregation of human islet amyloid polypeptide, endoplasmic reticulum and mitochondrial stress; and results in activation of NFκB in pancreatic ß cells. BPA also renders a major shift in ß to α cell ratio in islets causing deregulated glucagon secretion. Hence, understanding of various mechanisms of BPA action on the pancreatic islets will provide meaningful insights in recognizing the risk posed by exposure to low and high doses of BPA.

Contributions and Limitations of Mitochondria-Targeted and Non-Targeted Antioxidants in the Treatment of Parkinsonism: an Updated Review.

As conventional therapeutics can only treat the symptoms of Parkinson's disease (PD), major focus of research in recent times is to slow down or prevent the progression of neuronal degeneration in PD. Non-targeted antioxidants have been an integral part of the conventional therapeutics regimen; however, their importance have lessened over time because of their controversial outcomes in clinical PD trials. Inability to permeate and localize within the mitochondria remains the main drawback on the part of non-targeted antioxidants inspite of possessing free radical scavenging properties. In contrast, mitochondrial-targeted antioxidants (MTAs), a special class of compounds have emerged having high advantages over non-targeted antioxidants by virtue of efficient pharmacokinetics and better absorption rate with capability to localize many fold inside the mitochondrial matrix. Preclinical experimentations indicate that MTAs have the potential to act as better alternatives compared to conventional non-targeted antioxidants in treating PD; however, sufficient clinical trials have not been conducted to investigate the efficacies of MTAs in treating PD. Controversial clinical outcomes on the part of non-targeted antioxidants and lack of clinical trials involving MTAs have made it difficult to go ahead with a direct comparison and in turn have slowed down the progress of development of safer and better alternate strategies in treating PD. This review provides an insight on the roles MTAs and non-targeted antioxidants have played in the treatment of PD till date in preclinical and clinical settings and discusses about the limitations of mitochondria-targeted and non-targeted antioxidants that can be resolved for developing effective strategies in treating Parkinsonism.

Real-time sensitive detection of Cr (VI) in industrial wastewater and living cells using carbon dot decorated natural kyanite nanoparticles.

This article reports a facile strategy to detect hexavalent chromium (Cr (VI)) using a naturally formed mineral (kyanite) based fluorometric sensor. Nitrogenous carbon dots have been incorporated into natural kyanite (KYCD) nanoparticles causing a stable bright blue fluorescence compared to its pristine counterpart. This sensing probe structurally stabilizes and resists the agglomeration of carbon dots, thus retaining fluorescence quality for a longer period. The promising bright blue fluorescence has been utilized further to detect Cr (VI) in wastewater and living cells. Ease of synthesis, low cost, and stability of the system offers the benefit for large-scale production, which is convenient for industrial production the sensing probe. The sensor shows high selectivity and sensitivity (LOD and LOQ of 0.11 µM and 0.36 µM respectively in case of linear fitting, whereas 0.26 µM and 0.88 µM respectively for full range plot) towards hexavalent chromium in presence of other interfering elements. A detailed study of photoinduced electron transfer (PET) mediated rapid 'turn off' sensing mechanism was carried out using Time-Dependent Density functional (TDDFT) calculations. The sensing efficacy of the probe remains unaltered under a wide range of pH and can be effective in various water types. Onsite sampling and probing of Cr (VI) in tannery wastewater has been performed to validate its real-life efficiency that yields excellent results. The sensor can effectively detect chromium at a cellular level (HeLa cells) in a similar way as the bright blue fluorescence diminishes in presence of the quenching ion. Experimental in vitro studies along with theoretical docking analysis has been conducted to substantiate such issues and a higher possibility of fluorophore binding was found for Isoleucine (2.9 Å), Serine (2.96 Å), and Glycine (3.16 Å). This biocompatible sensor rapidly senses hexavalent chromium in living cells, which makes this efficient probe a true heavy metal-induced carcinogen sensor.

A comparison on the biochemical activities of Fluorescein disodium, Rose Bengal and Rhodamine 101 in the light of DNA binding, antimicrobial and cytotoxic study.

Biochemical activities of Fluorescein, Rose Bengal and Rhodamine 101 were studied by DNA binding, antibacterial and cytotoxic studies. DNA binding studies were done using spectroscopic, thermodynamic and molecular modeling techniques. Antibacterial activities were investigated against a gram-negative bacteria Escherichia coli and a gram-positive bacteria Staphylococcus aureus. Cytotoxic activities were studied against Wi-38 cell line. We observed these dyes bound to minor groove of DNA and structural diversity of dyes affect the phenomenon. No significant antibacterial and cytotoxic activities of these dyes were found in our observations.

Substance P failed to reverse dextran sulfate sodium-induced murine colitis mediated by mitochondrial dysfunction: implications in ulcerative colitis.

As controversy exists about the efficacy of substance P (SP) in treating ulcerative colitis (UC) with no previous study highlighting the impact of SP on mitochondrial dysfunction in this diseased condition, it became logical to perform the present study. C57BL/6 J mice were administered with DSS @ 3.5%/gm body weight for 3 cycles of 5 days each followed by i.v. dose of SP @ 5nmole per kg for consecutive 7 days. Histopathological features were noticed in the affected colon along with colonic mitochondrial dysfunction, alterations in mitochondrial stress variables and enhanced colonic cell death. Interestingly, SP failed to reverse colitic features and proved ineffective in inhibiting mitochondrial dysfunction. Unexpectedly SP alone seemed to impart detrimental effects on some of the mitochondrial functions, enhanced lipid peroxidation and increased staining intensities for caspases 3 and 9 in the normal colon. To substantiate in vivo findings and to assess free radical scavenging property of SP, Caco-2 cells were exposed to DSS with or without SP in the presence and absence of specific free radical scavengers and antioxidants. Interestingly, in vitro treatment with SP failed to restore mitochondrial functions and its efficacy proved below par compared to SOD and DMSO indicating involvement of O2 •- and •OH in the progression of UC. Besides, catalase, L-NAME and MEG proved ineffective indicating non-involvement of H2O2, NO and ONOO- in UC. Thus, SP may not be a potent anti-colitogenic agent targeting colonic mitochondrial dysfunction for maintenance of colon epithelial tract as it lacks free radical scavenging property.

Role of free radical scavenging activity of vasoactive intestinal peptide in the attenuation of mitochondrial dysfunction to ameliorate dextran sulphate sodium-induced colitis in mice: Implications in ulcerative colitis.

OBJECTIVE: To evaluate the efficacy of vasoactive intestinal peptide (VIP) in treating ulcerative colitis (UC), targeting colonic mitochondrial dysfunction by virtue of its free radical scavenging properties for maintenance of colon mucosal integrity. METHODS: A murine model was administered with dextran sodium sulfate (DSS) to induce colitis in C57BL/6J mice at 3.5%/g bodyweight for 3 cycles of 5 days each, followed by an intraperitoneal dose of VIP at 0.5 nmol/L per mouse per day for 10 days. The post-treatment mice were sacrificed and their colon samples were utilized for further analysis. To substantiate the in vivo findings and identify the reactive species involved in progression of UC, Caco-2 cells were subjected to DSS (5%) for 24 hours at 37 °C with or without VIP (10 nmol/L) in the presence or absence of specific free radical scavengers and antioxidants. RESULTS: Treatment with VIP reduced histopathological severity of colitis and cell death markers in murine model, leading to partial recovery of inhibited mitochondrial respiratory complexes, altered mitochondrial membrane potential and lowered adenosine triphosphate generation. Interestingly, in vitro treatment with VIP restored mitochondrial functions and its efficacy was equal to super oxide dismutase and dimethyl sulfoxide, indicating involvement of superoxide free radical (O2 •-) and hydroxyl radical (•OH) in progression of UC. However, catalase, Nω-nitro-l-arginine methyl ester and mercaptoethylguanidine were ineffective, indicating non-involvement of hydrogen peroxide, nitric oxide and ONOO- in UC. CONCLUSION: By virtue of its free radical scavenging properties VIP can act as a potent anti-colitogenic agent, reversing colonic mitochondrial dysfunction for treating UC.

Association of the STAT6 rs3024974 (C/T) Polymorphism with IgE-Mediated Food Sensitization among West Bengal Population in India.

INTRODUCTION: Genetic polymorphisms associated with IgE-mediated food sensitization have been a robust area of research for decades. A genome-wide search for susceptible loci regulating the IgE response (atopy) identified the candidate gene STAT6, which is important in the context of food allergic manifestations. OBJECTIVE: The present study was designed to investigate the sensitization of West Bengal population against some common allergenic food items and to study the role of the STAT6 gene polymorphism in elevating food-specific IgE levels among sensitized individuals. METHODS: Skin prick test was performed for 6 food items among 501 patients (126 children, 85 adolescents, and 290 adults)from West Bengal, India. Among them, 165 patients were selected for measurement of total IgE and food-specific IgE levels along with 165 controls. Finally, the STAT6 (rs3024974 (C/T) polymorphism was genotyped in 139 cases and control subjects. RESULTS: Shrimp was identified as a dominant food allergen in adolescents and adults, whereas milk sensitization was highest in children. Food-sensitized patients with onset during childhood had significantly higher total IgE levels compared to patients with onset during adulthood (p < 0.00001). The frequency of the rs3024974 CC genotype in both cases and control subjects (55.40 and 46.76%, respectively) was higher than that of CT or TT. Patients with childhood onset bearing the CC genotype had significantly higher specific IgE levels in comparison to those with adult onset (p = 0.001). CONCLUSION: Food sensitization has a genetic background and the rs3024974 polymorphism is associated with susceptibility and reaction severity in food-sensitized patients in West Bengal population in India.

Spermine and spermidine act as chemical chaperones and enhance chaperone-like and membranolytic activities of major bovine seminal plasma protein, PDC-109.

The major bovine seminal plasma protein, PDC-109, binds to choline phospholipids of the sperm plasma membrane and induces an efflux of cholesterol and choline phospholipids (cholesterol efflux), which is crucial for sperm capacitation. PDC-109 also exhibits chaperone-like activity and protects target proteins against various kinds of stress. Here we show that the polyamines spermine and spermidine, present in high concentration in the seminal plasma of various mammals, increase the ability of PDC-109 to perturb membrane structure as well as its chaperone-like activity. Interestingly, spermine/spermidine alone did not perturb membrane structure but exhibited chaperone-like activity by protecting target proteins against thermal and oxidative stress. When spermine/spermidine was used along with PDC-109, the observed chaperone-like activity was considerably higher than that expected for a simple additive effect, suggesting that PDC-109 and the polyamines act in a synergistic fashion. These results indicate that at the high concentrations present in the seminal plasma spermine/spermidine exhibit a positive modulatory effect on the chaperone-like activity of PDC-109 and may also function as chemical chaperones and protect other seminal plasma proteins from various kinds of stress.

Spectroscopic characterization of the interaction of phenosafranin and safranin O with double stranded, heat denatured and single stranded calf thymus DNA.

Interaction of phenosafranin and safranin O with double stranded, heat denatured and single stranded calf thymus DNA has been studied by fluorescence, absorbance and circular dichroic techniques. Binding to the double stranded and heat denatured DNA conformations induced strong quenching in the fluorescence spectra of both dyes. Linear Scatchard plots indicated the binding to be of one type and the affinity evaluated to be of the order of 10(5) M(-1) with double stranded and heat denatured DNAs. Fluorescence quenching was much weaker with the single stranded DNA and the binding affinity was one order lower. Ferrocyanide quenching studies revealed that the fluorescence emission of the dye molecules bound to the double stranded and heat denatured DNAs was quenched much less compared to that bound to the single stranded DNA. Further, there was significant emission polarization for the bound dyes and strong energy transfer from the DNA base pairs to the dye molecules indicating intercalative binding. Salt dependence of the binding phenomenon revealed that electrostatic forces have significant role in the binding process. The intercalation of these molecules to double stranded and heat denatured DNA and simple stacking to single strands was proved by these fluorescence techniques. Support to the fluorescence results have been derived from absorption and circular dichroic results. Phenosafranin was revealed to be a stronger binding species compared to safranin O.

Sequence-selective binding of phenazinium dyes phenosafranin and safranin O to guanine-cytosine deoxyribopolynucleotides: spectroscopic and thermodynamic studies.

The sequence selectivity of the DNA binding of the phenazinium dyes phenosafranin and safranin O have been investigated with four sequence-specific deoxyribopolynucleotides from spectroscopic and calorimetric studies. The alternating guanine-cytosine sequence selectivity of the dyes has been revealed from binding affinity values, circular dichroism, thermal melting, competition dialysis, and calorimetric results. The binding affinities of both the dyes to the polynucleotides were of the order of 10(5) M(-1), but the values were higher for the guanine-cytosine polynucleotides over adenine-thymine ones. Phenosafranin had a higher binding affinity compared to safranin O. Isothermal titration calorimetric studies revealed that the binding reactions were exothermic and favored by negative enthalpy and predominantly large positive entropy contributions in all cases except poly(dA)·poly(dT) where the profile was anomalous. Although charged, nonpolyelectrolytic contribution was revealed to be dominant to the free energy of binding. The negative heat capacity values obtained from the temperature dependence of enthalpy changes, which were higher for phenosafranin compared to safranin O, suggested significant hydrophobic contribution to the binding process. In aggregate, the data presents evidence for the alternating guanine-cytosine base pair selectivity of these phenazinium dyes and a stronger binding of phenosafranin over safranin O.