Structurally Dynamic Monocyte-Liposome Hybrid Vesicles as an Anticancer Drug Delivery Vehicle: A Crucial Correlation of Microscopic Elasticity and Ultrafast Dynamics.

A biomimetic cell-based carrier system based on monocyte membranes and liposomes has been designed to create a hybrid "Monocyte-LP" which inherits the surface antigens of the monocytes along with the drug encapsulation property of the liposome. Förster resonance energy transfer (FRET) and polarization gated anisotropy measurements show the stiffness of the vesicles obtained from monocyte membranes (Mons), phosphatidylcholine membranes (LP), and Monocyte-LP to follow an increasing order of Mons > Monocyte-LP > LP. The dynamics of interface bound water molecules plays a key role in the elasticity of the vesicles, which in turn imparts higher delivery efficacy to the hybrid Monocyte-LP for a model anticancer drug doxorubicin than the other two vesicles, indicating a critical balance between flexibility and rigidity for an efficient cellular uptake. The present work provides insight on the influence of elasticity of delivery vehicles for enhanced drug delivery.

Targeted Redox Balancing through Pulmonary Nanomedicine Delivery Reverses Oxidative Stress Induced Lung Inflammation.

Non-invasive delivery of drugs is important for the reversal of respiratory diseases essentially by-passing metabolic pathways and targeting large surface area of drug absorption. Here, we study the inhalation of a redox nano medicine namely citrate functionalized Mn3O4 (C-Mn3O4) duly encapsulated in droplet evaporated aerosols for the balancing of oxidative stress generated by the exposure of Chromium (VI) ion, a potential lung carcinogenic agent. Our optical spectroscopic in-vitro experiments demonstrates the efficacy of redox balancing of the encapsulated nanoparticles (NP) for the maintenance of a homeostatic condition. The formation of Cr-NP complex as an excretion of the heavy metal is also demonstrated through optical spectroscopic and high resolution transmission optical microscopy (HRTEM). Our studies confirm the oxidative stress mitigation activity of the Cr-NP complex. A detailed immunological assay followed by histopathological studies and assessment of mitochondrial parameters in pre-clinical mice model with chromium (Cr) induced lung inflammation establishes the mechanism of drug action to be redox-buffering. Thus, localised delivery of C-Mn3O4 NPs in the respiratory tract via aerosols can act as an effective nanotherapeutic agent against oxidative stress induced lung inflammation.

Inorganic-organic Synergy in Nano-hybrids Makes a New Class of Drug with Targeted Delivery: Glutamate Functionalization of Iron Nanoparticles for Potential Bone Marrow Delivery and X-ray Dynamic Therapy.

The direct delivery of therapeutic molecules is generally inefficient and has several problems. Hence, nanomedicines with targeted and controlled delivery applications have been an exciting field of research for the past decade. In this regard, the adjustable properties of inorganic nanoparticles like particle size distribution, ability to change the targeting ligand to have a higher affinity towards the pathologic cell, and controlled delivery properties have made them indispensable for targeted drug delivery applications. Changing the ligand on the surface of the inorganic nanoparticle can direct different therapeutic molecules to different organs like the liver, spleen, kidney, bone, and even brain. However, while the other targeted nanomedicines are well-reported, the targeting of therapeutics to bone marrow cells is sparse in the literature. Hence, the administration of therapeutics for bone-related disorders, like bone metastases, leads to several problems, such as severe systemic toxicity and suboptimal efficacy. In this direction, we have shown our successful effort to functionalise a model inorganic nanoparticle (Fe2O3) by glutamate ligand which is reported to have a high affinity towards the NMDA receptors of the bone cells. We have performed spectroscopic studies to characterize the nano-hybrid. We have shown that the cargo or the Fe2O3 nanoparticle possesses the ability to generate photo-induced reactive oxygen species (ROS), thereby leading to a therapeutic opportunity for bone metastases. In addition, the nanoparticle also possesses the ability to generate enhanced ROS on X-ray irradiation, which may provide a new strategy for bone metastases and cancer therapy. Also, this paper reviews the advancement in the drug delivery applications of inorganic nanoparticles and highlights the crosstalk between the inorganic nanoparticles with the conjugated targeting ligand for efficient delivery applications.

Supramolecular Dipeptide-Based Near-Infrared Fluorescent Nanotubes for Cellular Mitochondria Targeted Imaging and Early Apoptosis.

Herein, we have designed and synthesized unsymmetrical visible Cy-3 and near-infrared (NIR) Cy-5 chromophores anchoring mitochondria targeting functional group conjugated with a Phe-Phe dipeptide by a microwave-assisted Fmoc solid phase peptide synthesis method on Wang resin. These dipeptide-based Cy-3-TPP/FF as well as Cy-5-TPP/FF molecules self-assemble to form fluorescent nanotubes in solution, and it has been confirmed by TEM, SEM, and AFM. The Cy-3-TPP/FF and Cy-5-TPP/FF molecules in solution exhibit narrow excitation as well as emission bands in the visible and NIR region, respectively. These lipophilic cationic fluorescent peptide molecules spontaneously and selectively accumulate inside the mitochondria of human carcinoma cells that have been experimentally validated by live cell confocal laser scanning microscopy and display a high Pearson's correlation coefficient in a colocalization assay. Live cell multicolor confocal imaging using the NIR Cy-5-TPP/FF in combination with other organelle specific dye is also accomplished. Moreover, these lipophilic dipeptide-based cationic molecules reach the critical aggregation concentration inside the mitochondria because of the extremely negative inner mitochondrial membrane potential [(ΔΨm)cancer ≈ -220 mV] and form supramolecular nanotubes which are accountable for malignant mitochondria targeted early apoptosis. The early apoptosis is arrested using Cy-5-TPP/FF and confirmed by annexin V-FITC/PI apoptosis detection assay.

Eugenol emerges as an elixir by targeting ß-catenin, the central cancer stem cell regulator in lung carcinogenesis: an in vivo and in vitro rationale.

According to population-based studies, lung cancer has become one of the leading causes of death globally in males and is also rising in females at an alarming rate. The aim of this study was to exploit the inherent properties of eugenol to restrict the growth of cancer cells in a tobacco-related human carcinogen NDEA-induced lung carcinogenesis model in vivo as a chemopreventive agent. More precisely, by utilizing its abundance in nature, eugenol (a component of clove) was utilized to establish the molecular mechanism of chemoprevention in the NDEA-induced mouse lung carcinogenesis model in a substantial cost-effective manner and was validated in the A549 human lung cancer cell line. Our study especially targeted the tiny, drug-resistant, and most virulent subpopulation of cancer cells called CSCs by targeting their regulator molecule ß-catenin. The non-toxic dosage of eugenol was shown to enhance apoptosis, simultaneously suppressing cell proliferation in the lung tissue of carcinogen-treated mice without affecting the normal mice. Combining cellular apoptosis and proliferation, eugenol showed an exceptional chemopreventive potential in this lung carcinogenesis model. Importantly, eugenol strongly restricted the lung carcinoma in the mild dysplastic stage as a chemopreventive agent. The molecular analysis remarkably depicted the restriction of ß-catenin nuclear transportation. The minimized total ß-catenin pool and induced N-terminal Ser37 phosphorylation form after eugenol treatment resulted in its cytoplasmic degradation. Consequently, CSC markers such as CD44, Oct4, EpCAM, and Notcht1, whose expression is dependent on ß-catenin decreased significantly, as proven by IHC, ICC, and WB analysis both in vivo and in vitro. The in vitro secondary sphere formation assay also proved the remarkably repressed CSC population, and hence the virulence. In another way, eugenol was proven to significantly enhance the degradation of ß-catenin when treated with the CK1α inhibitor D4476 in vitro by Western blot. CK1α in the Wnt/ß-catenin pathway plays a crucial role for tagging with the N-terminal Ser45 phosphorylation of ß-catenin, which ultimately opens a position for the decisive phosphorylation by GSK3ß at the Ser37 residue to take place. Thus, the conclusive extermination of CSCs achieved that was associated with recurrence due to treatment failure. That can help to achieve a longer and better quality of life in a natural, economical way.

The drug resistance mechanisms in Leishmania donovani are independent of immunosuppression.

The protozoan parasite L. donovani resides inside macrophages as amastigotes and inflicts a potentially lethal disease visceral leishmaniasis (VL). Due to absence of a vaccine, chemotherapy with antimonials, amphotericin B, miltefosine or paromomycin remains the only option for treating VL. Prolonged treatment with a single drug resulted in parasite strains resistant to each of these drugs. As immuno-suppression characterizes the disease, we examined whether eliciting immunosuppressive cytokines is a mechanism of manifestation of drug-resistance. We infected BALB/c mice with the clinical isolates of L. donovani- BHU1066 (sensitive), NS2 (antimony-resistant), BHU1064 (miltefosine-resistant), BHU919 (Amphotericin B-resistant) and BHU1020 (paromomycin-resistant)- from the respective drug-unresponsive patients and assessed splenic parasite load and production of pro-inflammatory and anti-inflammatory cytokines. Although the splenic parasite loads in the drug-resistant L. donovani-infected BALB/c mice were higher than that observed in the drug-sensitive parasites-infected mice, the cytokine profiles were not significantly different between these two sets of mice. The drug-resistance in L. donovani results from innate drug modulation but perhaps not from host immune-suppressive cytokines.

Spectroscopic Studies on the Biomolecular Recognition of Toluidine Blue: Key Information Towards Development of a Non-Contact, Non-Invasive Device for Oral Cancer Detection.

Molecular interaction of aromatic dyes with biological macromolecules are important for the development of minimally invasive disease diagnostic biotechnologies. In the present work, we have used Toluidine Blue (TB) as a model dye, which is a well-known staining agent for the diagnosis of oral cancer and have studied the interaction of various biological macromolecules (protein and DNA) with the dye at different pH. Our spectroscopic studies confirm that TB interacts with Human Serum Albumin (HSA), a model protein at very high pH conditions which is very hard to achieve physiologically. On the other hand, TB significantly interacts with the DNA at physiological pH value (7.4). Our molecular studies strengthen the understanding of the Toluidine Blue staining of cancer cells, where the relative ratio of the nucleic acids is higher than the normal intracellular content. We have also developed a non-invasive, non-contact spectroscopic technique to explore the possibility of quantitatively detecting oral cancer by exploiting the interaction of TB with DNA. We have also reported development of a prototype named "Oral-O-Scope" for the detection of Oral cancer and have carried out human studies using the prototype.

Ribosylation induced structural changes in Bovine Serum Albumin: understanding high dietary sugar induced protein aggregation and amyloid formation.

Non-enzymatic glycation of proteins is believed to be the root cause of high dietary sugar associated pathophysiological maladies. We investigated the structural changes in protein during progression of glycation using ribosylated Bovine Serum Albumin (BSA). Non enzymatic attachment of about 45 ribose molecules to BSA resulted in gradual reduction of hydrophobicity and aggregation as indicated by red-shifted tryptophan fluorescence, reduced ANS binding and lower anisotropy of FITC-conjugated protein. Parallely, there was a significant decrease of alpha helicity as revealed by Circular Dichroism (CD) and Fourier transformed-Infra Red (FT-IR) spectra. The glycated proteins assumed compact globular structures with enhanced Thioflavin-T binding resembling amyloids. The gross structural transition affected by ribosylation led to enhanced thermostability as indicated by melting temperature and Transmission Electron Microscopy. At a later stage of glycation, the glycated proteins developed non-specific aggregates with increase in size and loss of amyloidogenic behaviour. A parallel non-glycated control incubated under similar conditions indicated that amyloid formation and associated changes were specific for ribosylation and not driven by thermal denaturation due to incubation at 37 °C. Functionality of the glycated protein was significantly altered as probed by Isothermal Titration Calorimetry using polyphenols as substrates. The studies demonstrated that glycation driven globular amyloids form and persist as transient intermediates during formation of misfolded glycated adducts. To the best of our knowledge, the present study is the first systematic attempt to understand glycation associated changes in a protein and provides important insights towards designing therapeutics for arresting dietary sugar induced amyloid formation.

Supramolecular ß-Sheet Forming Peptide Conjugated with Near-Infrared Chromophore for Selective Targeting, Imaging, and Dysfunction of Mitochondria.

Herein, conjugation of the amyloid-ß (Aß) peptide fragment, Lys-Leu-Val-Phe-Phe (KLVFF, fragment of Aß16-20), with an unsymmetrical near-infrared (NIR) cyanine-5 (Cy-5) chromophore is achieved using microwave-assisted solid phase synthesis on 2-chlorotrityl chloride resin. Selective mitochondria tracking and staining in human carcinoma cells are accomplished by the KLVFF/Cy-5 conjugate containing triphenylphosphonium functionality, and this is compared to a control molecule KLVFF/Cy-5c. Mitochondrial target specificity of KLVFF/Cy-5 is established by the colocalization assay using mitochondria selective probe MitoTracker Red, which is monitored by confocal laser scanning microscope and shows a high Pearson's correlation coefficient. The KLVFF/Cy-5 conjugate has high photostability, NIR absorption/emission, high molar extinction coefficient, narrow absorption/emission band, high fluorescence lifetime, and high fluorescence quantum yield. Moreover, mitochondria targeting KLVFF/Cy-5 conjugate reaches the critical aggregation concentration inside the mitochondria of cancer cells due to the strong negative inner mitochondrial membrane potential [(ΔΨm)cancer -220 mV] and self-assembles to form amyloid fibrils at the target site, which is responsible for the mitochondrial dysfunction and cytotoxicity. Annexin V-FITC/PI apoptosis detection assay is used to determine the signal pathway of mitochondria targeted cellular dysfunction.

Protein assembled nano-vehicle entrapping photosensitizer molecules for efficient lung carcinoma therapy.

The efficiency of drug depends not only on its potency but also on its ability to reach the target sites in preference to non-target sites. In this regard, protein assembled nanocarrier is the most promising strategy for intracellular anti-cancer drug delivery. The key motive of this study is to fabricate biocompatible protein assembled nanocarrier conjugated photosensitizer system for stimuli-responsive treatment of lung carcinoma. Here, we have synthesized a unique nanohybrid of protein assembled gold nanoparticles (AuNPs), attaching a model photosensitizer, Protoporphyrin IX (PpIX) to the protein shell of the nanoparticles (NPs) imparting an ideal drug-carrier nature. Photo-induced alteration in hydrodynamic diameter suggests structural perturbation of the nanohybrid which in terms signifies on-demand drug delivery. The drug release profile has been further confirmed by using steady-state fluorescence experiments. AuNP-PpIX showed excellent anti-cancer efficiency upon green light irradiation on lung adenocarcinoma cell line (A549) through intracellular reactive oxygen species (ROS) generation. The cellular morphological changes upon PDT and internalization of nanohybrid were monitored using confocal laser scanning microscope. This anti-cancer effect of nanohybrid was associated with apoptotic pathway which was confirmed in the flow cytometric platform. The developed nanomedicine is expected to find relevance in clinical anti-cancer PDT models in the near future.

Eugenol restricts Cancer Stem Cell population by degradation of ß-catenin via N-terminal Ser37 phosphorylation-an in vivo and in vitro experimental evaluation.

Eugenol a phenylpropanoid, predominantly found in clove is a very common spice in daily cuisine. It already reported to have anti-breast cancer activity. In this study, the effect of eugenol on CSC (Cancer Stem Cell) markers and its main regulator ß-catenin both in vivo Ehrlich Ascites Carcinoma (EAC) cell line and in vitro MCF-7 cell line was investigated with that of the untreated group. The therapeutic doses were found to significantly induce apoptosis leaving normal mice and cells unaffected. The in-depth analysis revealed the downregulation of ß-catenin thereby facilitating its degradation by N-terminal phosphorylation of Ser37 residue. Significant downregulation of various CSC markers was also observed in vivo after eugenol treatment those are regulated by the intracellular status of ß-catenin. These findings were validated by the effect of eugenol on the formation of the secondary sphere in vitro. Notable downregulation of the enriched stemness of secondary mammosphere was detected by the significantly decreased percentage of CD44+/CD24-/low population after eugenol treatment along with their distorted morphology and smaller the number of spheres. The underlying mechanism revealed significant downregulation of ß-catenin and the set of CSC markers along with their reduced mRNA expression in secondary sphere culture. Therefore, it can be concluded from the study that eugenol exerts its chemotherapeutic potential by impeding ß-catenin nuclear translocation thereby promoting its cytoplasmic degradation as a result stemness is being suppressed potentially even if in the enriched state. Therefore the study contributes to reduce the cancer-induced complications associated with the CSC population. This will ultimately confer the longer and improved patient's life.

Targeting and Imaging of Mitochondria Using Near-Infrared Cyanine Dye and Its Application to Multicolor Imaging.

Herein, we report water-soluble mitochondria-selective molecules that consist of a target-specific moiety conjugated with a near-infrared (NIR) imaging agent through variable spacer length. The presented NIR fluorescent cyanine-5 (Cy-5) chromophore exhibits excellent photostability, narrow NIR absorption and emission bands, high molar extinction coefficient, high fluorescence quantum yield, and long fluorescence lifetime. The biological compatibility and negligible cytotoxicity further make the dye an attractive choice for biological applications. Confocal fluorescence microscopic studies in the fixed human lung carcinoma cell line (A549) stained with the targeting NIR Cy-5 dyes (Cy-5a and Cy-5b) at 700 nM concentration show their cellular uptake and localization, which is compared with the nontargeting Cy-5c. Mitochondrial target specificity is demonstrated by colocalization experiments using the mitochondrion-tracking probe, MitoTracker Red and lysosome-tracking probe, LysoTracker Green. Multicolor imaging of cellular organelles in A549 cells is achieved in combination with suitable target-specific dyes with distinct excitation and emission, such as green emitting FM 1-43FX to selectively image the plasma membrane, blue-fluorescent DAPI to stain the nucleus, and the synthesized NIR Cy-5 to image the mitochondria. Higher accumulation of the dye inside the cancer cell mitochondria compared to the noncancerous cell is also demonstrated.

Autophagy protects peripheral blood mononuclear cells against inflammation, oxidative and nitrosative stress in diabetic dyslipidemia.

BACKGROUND: Type 2 diabetes mellitus (T2DM) results in severe oxidative and nitrosative stress and inflammation when associated with hyperlipidemia. In this study, we have attempted to explore the role of autophagy in T2DM subjects with or without dyslipidemia. METHODS: Experiments were carried out in isolated Peripheral blood mononuclear cells (PBMC) from study subjects and insulin resistant HepG2 cells utilizing flow cytometry, confocal microscopy and molecular biology techniques like western blotting, immunofluorescence and real time PCR. RESULTS: In case of T2DM with dyslipidemia, higher population of autophagy positive cell was detected compared to T2DM which may have been originated due to higher stress. Flow cytometric data indicated autophagy to be triggered by both oxidative and nitrosative stress in PBMC of diabetic dyslipidemic patients, which is a novel finding of our work. Expression of LC3 puncta, a hallmark of autophagy was observed at periphery of PBMC and Hep G2 cells in case of diabetic dyslipidemic condition. Increased expression of ATG5, LC3B and Beclin1 supports the autophagic pathway in both PBMC and Hep G2 cells. Upon blocking autophagy by 3-methyl adenine (3MA), the apoptotic cell population increased significantly. Autophagy was also been evidenced to control oxidative stress mediated up-regulation of inflammatory markers like IL-6, TNF-α. CONCLUSION: Induction of autophagy emerged to be a protective mechanism for the diabetic cells coupled with dyslipidemia. Not only Reactive oxygen species, but also reactive nitrogen species was involved in autophagy induction process. Moreover inhibition study documented autophagy to have a protective role in pro-inflammatory responses. Thus, enhancing autophagic activity may be an efficient mechanism leading to new therapeutic strategy to restore the glycemic regulation.

Spectroscopic Studies on Dual Role of Natural Flavonoids in Detoxification of Lead Poisoning: Bench-to-Bedside Preclinical Trial.

Ubiquitousness in the target organs and associated oxidative stress are the most common manifestations of heavy-metal poisoning in living bodies. While chelation of toxic heavy metals is important as therapeutic strategy, scavenging of increased reactive oxygen species, reactive nitrogen species and free radicals are equally important. Here, we have studied the lead (Pb) chelating efficacy of a model flavonoid morin using steady-state and picosecond-resolved optical spectroscopy. The efficacy of morin in presence of other flavonoid (naringin) and polyphenol (ellagic acid) leading to synergistic combination has also been confirmed from the spectroscopic studies. Our studies further reveal that antioxidant activity (2,2-diphenyl-1-picrylhydrazyl assay) of the Pb-morin complex is sustainable compared to that of Pb-free morin. The metal-morin chelate is also found to be significantly soluble compared to that of morin in aqueous media. Heavy-metal chelation and sustainable antioxidant activity of the soluble chelate complex are found to accelerate the Pb-detoxification in the chemical bench (in vitro). Considering the synergistic effect of flavonoids in Pb-detoxification and their omnipresence in medicinal plants, we have prepared a mixture (SKP17LIV01) of flavonoids and polyphenols of plant origin. The mixture has been characterized using high-resolution liquid chromatography assisted mass spectrometry. The mixture (SKP17LIV01) containing 34 flavonoids and 76 other polyphenols have been used to investigate the Pb detoxification in mouse model. The biochemical and histopathological studies on the mouse model confirm the dual action in preclinical studies.

Porphyrins to restrict progression of pancreatic cancer by stabilizing KRAS G-quadruplex: In silico, in vitro and in vivo validation of anticancer strategy.

KRAS, a frequently mutated G-quadruplex forming proto-oncogene is responsible for almost every type of cancer which can form a parallel G-quadruplex structure in the promoter region. G-quadruplex structure is one of the most important drug targets for modern cancer therapy for their unique structure and specificity. Here, we have screened several synthetic porphyrin-based compounds as potential KRAS G-quadruplex stabilizing ligands, using molecular modeling and docking studies. Two novel porphyrins: Porphyrin-1(Cobalt containing) and Porphyrin-2 (Palladium containing) evidenced high affinity towards KRAS-promoter/G-quadruplex. As KRAS mutation is prevalent in pancreatic cancer, the efficacy of these ligands against human pancreatic ductal carcinoma cell line PANC-1 and MiaPaCa2 were examined. Both the Porphyrins exhibited significant cytotoxicity and block metastasis by inhibiting Epithelial to messenchymal transition. In vivo studies confirmed both porphyrin compounds to be effective against EAC tumors along with significantly low toxicity against normal Swiss albino mice. The expression of KRAS gene in porphyrin-treated PANC-1, MiaPaCa2 and tumor-derived EAC cells were drastically reduced at both protein and RNA levels. Thus interaction of porphyrin-based ligands with G-quadruplex DNA at the promoter region of KRAS, might be utilized as a target for anticancer therapeutic strategy.

Inbred mouse strains differentially susceptible to Leishmania donovani infection differ in their immune cell metabolism.

Leishmania donovani is a protozoan parasite that infects mammalian macrophages, wherein the parasite resides and replicates as amastigotes, inflicting the potentially fatal disease visceral leishmaniasis. The disease is characterized by severe immunosuppression and hypocholesterolemia implying metabolic changes in L. donovani infection; whether such metabolic changes are also linked to susceptibility to the infection is not known. Herein, four inbred mouse strains were first characterized for their resistance or susceptibility profile to L. donovani infection. It was observed that these four mouse strains were differentially susceptible to L. donovani infection. Splenic expression of four key cytokines- IL-10, IL-12, IFN-γ and IL-4- revealed that the differential susceptibility of these four mouse strains to L. donovani was partially associated with these cytokines. The association was further correlated with the expression of different enzymes of the glycolytic pathway in the spleen of these L. donovani-infected mice. Thus, the observations reported here suggest an association between host metabolism, cytokine secretion profile and L. donovani susceptibility. As the chemotherapeutic choices are extremely limited and a vaccine for human use is yet to be discovered for the neglected tropical disease that is prevalent in 88 countries affecting 320 million people, this metabolic study is a significant research area that has potentials to develop a new target for anti-leishmanial chemotherapy.

An insight to the binding of ellagic acid with human serum albumin using spectroscopic and isothermal calorimetry studies.

Ellagic acid (EA), a natural polyphenol evidence several pharmacological benefits. The binding profile of EA with human serum albumin (HSA) has been explored and investigated by Isothermal titration calorimetry (ITC), circular dichroism (CD) spectroscopy, time-correlated single-photon counting (TCSPC), absorbance spectroscopy, steady-state fluorescence spectroscopy, and modelling studies. The ITC data analysis revealed the binding Constant (Ka), ΔH, ΔS and ΔG values to be 15.5×104M-1, -116.2±18.1 Kcal mol-1, -366 cal mol-1K-1 and -7.13 Kcal mol-1 respectively with a unique binding site at HSA. EA effectively quenched the intrinsic fluorescence of HSA by static quenching, whereas TCSPC data also revealed association of dynamic quenching also. Thermodynamic analysis confirmed that hydrophobic and mainly hydrogen bonding interaction played important role in stabilizing the HSA-EA complex. It further dictates the binding reaction to be enthalpy driven. The secondary structure of HSA was altered upon binding with EA. CD spectroscopic data indicated the fraction of alpha helicity to be decreased from 52% to 40% upon binding to EA. This study will provide an insight on evaluation of this bioactive interaction during transport and releasing efficiency at the target site in human physiological system since HSA is the most important carrier protein in blood serum.

Interaction of KRAS G-quadruplex with natural polyphenols: A spectroscopic analysis with molecular modeling.

Researchers are endeavoring to find out new therapeutics for curing cancer and G-quadruplex DNA has already been identified as a prospective one in this venture. Stabilizing G-quadruplex structures of telomere has emerged to be an important strategy in this context. Mutation in KRAS is mostly responsible for pancreatic, lung and colon cancer. In this present study we explored binding and conformational behaviour of G-quadruplex with different ligands by utilizing several biophysical techniques. Natural polyphenols like Curcumin and Ellagic acid were observed to bind with the G-quadruplex and enhance the melting temperature significantly indicating higher stability. UV-vis spectroscopy confirms formation of G quadruplex-ligand complex for both the compounds with specific binding affinity. Fluorimetric studies revealed that Ellagic acid had stronger binding affinity, 1.10×10(5)M(-1) compared to Curcumin, 1.6×10(4)M(-1) towards G-quadruplex. Interestingly, Curcumin provides greater stability by stacking on the top of the quadruplex structure with the help of the loops compared to Ellagic acid as is evident by docking studies. The keto form of curcumin showed stronger affinity than the enol form. We have developed a general model to estimate the influence of the ligands towards stabilizing the G-quadruplex subsequently characterizing the binding profile to enlighten prospective therapeutics.

Antimicrobial activities of actinomycetes isolated from unexplored regions of Sundarbans mangrove ecosystem.

BACKGROUND: New broad spectrum antimicrobial agents are urgently needed to combat frequently emerging multi drug resistant pathogens. Actinomycetes, the most talented group of microorganisms isolated from unexplored regions of the world may be the ultimate solution to this problem. Thus the aim of this study was to isolate several bioactive actinomycetes strains capable of producing antimicrobial secondary metabolite from Sundarbans, the only mangrove tiger land of the world. RESULTS: Fifty four actinomycetes were isolated and analyzed for antimicrobial activity against fifteen test organisms including three phytopathogens. Nine morphologically distinct and biologically active isolates were subjected to polyphasic identification study.16 s rDNA sequencing indicated eight isolates to reveal maximum similarity to the genus streptomyces, whereas one isolate presented only 93.57% similarity with Streptomyces albogriseolus NRRL B-1305(T). Seventy-one carbon sources and twenty-three chemical sources utilization assay revealed their metabolic relatedness. Among these nine isolates three specific strains were found to have notably higher degree of antimicrobial potential effective in a broader range including phyto-pathogenic fungus. Finally the strain SMS_SU21, which showed antimicrobial activity with MIC value of 0.05 mg ml(-1) and antioxidant activity with IC50 value of 0.242 ± 0.33 mg ml(-1) was detected to be the most potential one. True prospective of this strain was evaluated utilizing GC-MS and the bioactive compound responsible for antimicrobial activity was purified. CONCLUSION: Rare bioactive actinomycetes were isolated from unexplored heritage site. Antimicrobial compound has also been identified and purified which is active against a broad range of pathogens.

Overview of platelet physiology: its hemostatic and nonhemostatic role in disease pathogenesis.

Platelets are small anucleate cell fragments that circulate in blood playing crucial role in managing vascular integrity and regulating hemostasis. Platelets are also involved in the fundamental biological process of chronic inflammation associated with disease pathology. Platelet indices like mean platelets volume (MPV), platelets distributed width (PDW), and platelet crit (PCT) are useful as cheap noninvasive biomarkers for assessing the diseased states. Dynamic platelets bear distinct morphology, where α and dense granule are actively involved in secretion of molecules like GPIIb , IIIa, fibrinogen, vWf, catecholamines, serotonin, calcium, ATP, ADP, and so forth, which are involved in aggregation. Differential expressions of surface receptors like CD36, CD41, CD61 and so forth have also been quantitated in several diseases. Platelet clinical research faces challenges due to the vulnerable nature of platelet structure functions and lack of accurate assay techniques. But recent advancement in flow cytometry inputs huge progress in the field of platelets study. Platelets activation and dysfunction have been implicated in diabetes, renal diseases, tumorigenesis, Alzheimer's, and CVD. In conclusion, this paper elucidates that platelets are not that innocent as they keep showing and thus numerous novel platelet biomarkers are upcoming very soon in the field of clinical research which can be important for predicting and diagnosing disease state.