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1.
Cell Death Discov ; 10(1): 30, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38225229

ABSTRACT

Mitochondrial damage and the resultant oxidative stress are associated with neurodegenerative diseases, ageing, and cancer. However, the triggers of mitochondrial damage remain unclear. We previously reported that cell-free chromatin particles (cfChPs) released from the billions of cells that die in the body every day can readily enter healthy cells and damage their DNA. Here, we show that cfChPs isolated from the sera of healthy individuals, when applied to NIH3T3 mouse fibroblast cells, cause physical damage to mitochondrial DNA (mtDNA). cfChPs also induce ultrastructural changes, increase mitochondrial mass, alter mitochondrial shape, upregulate mitochondrial outer membrane protein translocase of the outer membrane 20, and change mitochondrial membrane potential. Furthermore, a marked increase was observed in mitochondrial superoxide (ROS) production, as detected by MitoSOX Red, and intracellular superoxide dismutase-1 activation. ROS production was also activated when a conditioned medium containing cfChPs released from hypoxia-induced dying NIH3T3 cells was applied to healthy NIH3T3 cells. ROS activation was significantly reduced when the conditioned medium was pre-treated with three different cfChP-deactivating agents: anti-histone antibody-complexed nanoparticles, DNase I, and the novel pro-oxidant combination of the nutraceuticals resveratrol and copper. Given that 1 × 109-1 × 1012 cells die in the body every day, we hypothesise that cfChPs from dying cells are the major physiological triggers for mtDNA damage and ROS production. Deactivation of cfChPs may provide a novel therapeutic approach to retard ageing and associated degenerative conditions linked to oxidative stress.

2.
Nat Prod Res ; : 1-10, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38066709

ABSTRACT

A new pregnane, 12ß-O-acetyl-20(S)-O-N-methylanthranilyl-3ß, 8ß, 14ß, 17α-tetrol pregn-5-ene (12ß-O-acetyl-20(S)-O-N-methylanthranilyl-sarcostin) have been isolated from Marsdenia tenacissima (family: Asclepediaceae). The structure of new pregnane was elucidated by using spectroscopic techniques,1H,13C NMR, HMBC, HSQC, COSY and TOCSY and ESI-MS Mass spectrometry.

3.
Nat Prod Res ; : 1-10, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38099376

ABSTRACT

Plants of Asclepiadaceae and Apocynaceae family are a rich source of pregnane and pregnane glycosides. They are found in nature either in free state or as their glycosides. They have shown antitumor, anticancer, and hypoglycaemic, antioxidant and antimicrobial activities. In our continued studies on the isolation of pregnane glycosides we have isolated a novel pregnane pentaglycoside comprised of 2-deoxy and 2, 6-dideoxy monosaccharides from Wattakaka lanceolata (Asclepiadaceae). The structure of the new glycoside, Geneoside was established as11α, 12ß-O-diacetyl-drevogenin-P-3-O-ß-D-cymaropyaranosyl (1→4)-ß-D-cymaropyranosyl (1→4) -ß-D-Oleandropyranosyl (1→4)-ß-D-digitalopyranosyl (1→4)-ß-D-digitalopyranoside. The stereoscopic structure was established by chemical degradation, chemical transformation and recent physicochemical techniques viz 1H,13C, 2-D NMR (COSY, TOCSY, HSQC and HMBC) and Mass spectrometry.

4.
Med Chem ; 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37946341

ABSTRACT

OBJECTIVE: The chemical transformation of ursolic acid (UA) into novel C-3 aryl ester derivatives and in vitro and silico assessment of their antitubercular potential. BACKGROUND: UA is a natural pentacyclic triterpenoid with many pharmacological properties. Semisynthetic UA analogs have demonstrated enhanced anticancer, antimalarial, and antifilarial properties in our previous studies. METHOD: The C-30 carboxylic group of previously isolated UA was protected, and various C-3 aryl ester derivatives were semi-synthesized. The agar dilution method was used to evaluate the in vitro antitubercular efficacy of Mycobacterium tuberculosis (Mtb) H37Ra. In silico docking studies of the active derivative were carried out against Mtb targets, catalase peroxidase (PDB: 1SJ2), dihydrofolate reductase (PDB: 4M2X), enoyl-ACP reductase (PDB: 4TRO), and cytochrome bc1 oxidase (PDB: 7E1V). RESULTS: The derivative 3-O-(2-amino,3-methyl benzoic acid)-ethyl ursolate (UA-1H) was the most active among the eight derivatives (MIC1 2.5 µg/mL) against Mtb H37Ra. Also, UA-1H demonstrated significant binding affinity in the range of 10.8-11.4 kcal/mol against the antiTb target proteins, which was far better than the positive control Isoniazid, Ethambutol, and co-crystallized ligand (HEM). Moreover, the predicted hit UA-1H showed no inhibition of Cytochrome P450 2D6 (CYP2D6), suggesting its potential for favorable metabolism in Phase I clinical studies. CONCLUSION: The ursolic acid derivative UA-1H possesses significant in vitro antitubercular potential with favorable in silico pharmacokinetics. Hence, further in vivo assessments are suggested for UA-1H for its possible development into a secure and efficient antitubercular drug.

5.
Front Immunol ; 14: 1331491, 2023.
Article in English | MEDLINE | ID: mdl-38274821

ABSTRACT

Immune checkpoint blockade is the exciting breakthrough in cancer, but how immune checkpoints are activated is unknown. We have earlier reported that cell-free chromatin particles (cfChPs) that circulate in blood of cancer patients, or those that are released locally from dying cancer cells, are readily internalized by healthy cells with biological consequences. Here we report that treatment of human lymphocytes with cfChPs isolated from sera of cancer patients led to marked activation of the immune checkpoints PD-1, CTLA-4, LAG-3, NKG2A, and TIM-3. This finding was corroborated in vivo in splenocytes of mice when cfChPs were injected intravenously. Significant upregulation of immune checkpoint was also observed when isolated lymphocytes were exposed to conditioned medium containing cfChPs released from hypoxia-induced dying HeLa cells. Immune checkpoint activation could be down-regulated by pre-treating the conditioned media with three different cfChPs deactivating agents. Down-regulation of immune checkpoints by cfChPs deactivating agents may herald a novel form of immunotherapy of cancer.


Subject(s)
Chromatin , Neoplasms , Humans , Animals , Mice , HeLa Cells , Immunotherapy , Lymphocytes , Neoplasms/therapy
6.
Front Oncol ; 12: 1000957, 2022.
Article in English | MEDLINE | ID: mdl-36185249

ABSTRACT

Background: Our earlier studies have shown that cell-free chromatin particles (cfChPs) that are released from dying cancer cells are readily internalised by bystander cells leading to activation of two hallmarks of cancer viz. genome instability and inflammation. These hallmarks could be down-regulated by deactivating cfChPs via medium of oxygen radicals generated upon admixing small quantities of the nutraceuticals resveratrol (R) and copper (Cu). In this exploratory study, we investigated whether oral administration of R and Cu (R-Cu) would down-regulate the hallmarks of cancer and immune checkpoints in advanced squamous cell carcinoma of oral cavity (OSCC). Patients and methods: The study comprised of 25 patients divided into 5 equal groups. Five patients acted as controls; the remaining 20 were given R-Cu in four escalating doses. The lowest dose of R-Cu was 5.6mg and 560ng respectively, and the highest dose was 500mg and 5mg respectively. An initial biopsy was taken from patients at first presentation, and a second biopsy was taken 2 weeks later on the operating table. R-Cu was administered orally twice daily in the intervening period. Confocal microscopy was performed on tumour sections after fluorescent immuno-staining with anti-DNA and anti-histone antibodies to detect presence of cfChPs in the tumour micro-environment (TME). Immunofluorescence analysis was performed for 23 biomarkers representing the 10 Hallmarks of cancer, including 5 immune checkpoints, defined by Hanahan and Weinberg. Results: Confocal microscopy detected copious presence of cfChPs in TME of OSCC, which were eradicated/deactivated following two-week treatment with R-Cu. Eradication of cfChPs from TME was associated with marked down-regulation of 21/23 biomarkers, including the five immune checkpoints. The lower two doses of R-Cu were more effective than the higher doses. No adverse effects attributable to R-Cu were observed. Conclusion: These results suggest that cfChPs released into TME from dying cancer cells are global instigators for cancer hallmarks and immune checkpoints in surviving cancer cells. The ability of R-Cu to deactivate cfChPs raises the prospect of a novel and non-toxic form of cancer treatment which sans killing of cancer cells, and instead induces healing by down-regulating cancer hallmarks and immune check-points. Clinical Trial Registration: http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=19801&EncHid=&userName=CTRI/2018/03/012459.

7.
PLoS One ; 17(2): e0262212, 2022.
Article in English | MEDLINE | ID: mdl-35120140

ABSTRACT

BACKGROUND: Transplant related toxicity is a major therapeutic challenge. We have previously reported that the toxicity of chemotherapy is largely not directly because of the drugs themselves; rather it is mainly due to DNA damage, apoptosis and hyper-inflammation triggered by cell-free chromatin particles that are released because of drug-induced host cell death. Cell-free chromatin particles can be inactivated by free-radicals which are generated when the nutraceuticals resveratrol and copper are administered orally. We investigated if a combination of resveratrol and copper would reduce transplant related toxicities in an exploratory, prospective dose-escalation study. PATIENTS AND METHODS: Twenty-five patients with multiple myeloma were enrolled between March 2017 to August 2019. Patients were divided into 3 groups: control (Group 1, N = 5) received vehicle alone; group 2 (N = 15) received resveratrol-copper at dose level I (resveratrol = 5.6 mg and copper = 560 ng); group 3 (N = 5) received resveratrol-copper at dose level II (resveratrol = 50 mg and copper = 5 µg). The dose was given twice daily with the first dose administered 48 hours before administering melphalan and continued until day +21 post-transplant. Common Terminology Criteria for Adverse Events version 4.02 was used to assess toxicities which included oral mucositis, nausea, vomiting and diarrhea. Measurement of inflammatory cytokines was done by ELISA. RESULTS: All patients (100%) in the control group developed grade 3/4 oral mucositis compared to 8/20 (40%) in both resveratrol-copper group 2 plus group 3 combined (P = 0.039). Reduction in inflammatory cytokines: salivary TNF - α (p = 0.012) and IL-1ß (p = 0.009) in dose level I but not in dose level II was observed. CONCLUSIONS: A combination of resveratrol-copper reduced transplant related toxicities in patients with multiple myeloma receiving high dose melphalan. We conclude that relatively inexpensive nutraceuticals may be useful as adjuncts to chemotherapy to reduce its toxicity. REGISTRATION: The trial was registered under Clinical Trial Registry of India (no.CTRI/2018/02/011905).


Subject(s)
Melphalan
8.
Oral Oncol ; 114: 105078, 2021 03.
Article in English | MEDLINE | ID: mdl-33183996

ABSTRACT

We recruited 69 consecutive patients with oral cavity squamous cell carcinoma (OSCC) between January 2017 and January 2019 for this study. All patients underwent up-front surgery followed by adjuvant radio- and/or chemotherapy as indicated. Pre-operative serum levels of C-reactive protein (CRP) and cell-free chromatin (cfCh) were estimated by ELISA and post-operative histopathological features were recorded. CRP levels were significantly associated with poor histopathological features, advanced stage, bone erosion, extracapsular spread and pathological nodal status. CRP levels were not associated with survival. CfCh levels were significantly associated with bone erosion and neck nodes and patients with higher cfCh levels had significantly poor overall survival.


Subject(s)
C-Reactive Protein/metabolism , Carcinoma, Squamous Cell/blood , Chromatin/metabolism , Mouth Neoplasms/blood , Carcinoma, Squamous Cell/mortality , Female , Humans , Male , Mouth Neoplasms/mortality
9.
Carbohydr Res ; 494: 108053, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32559510

ABSTRACT

An efficient three component coupling of aromatic aldehyde, deoxy sugar based alkyne (α-2-deoxy propargyl glycoside) and heterocyclic amine have been refluxed to synthesize stereoselective chiral propargylamines with good to excellent yield using only CuI catalyst along with bifunctional ligand l-proline. This method has proved to be applicable in wide range of substrates and found highly enantioselective with respect to earlier reported methods. In addition, l-proline was found as a chiral source which demonstrated that it could be developed as a highly enantioselective method for the construction of deoxy sugar based chiral propargylamines. The ligand l-proline was used for the first time in enantioselective A3-coupling reaction of α-2-deoxy propargyl glycosides involving substituted aromatic aldehyde and heterocyclic amines. Herein, we have synthesized 15 novel compounds based on A3-coupling reaction and structures of all the enantioselective compounds were characterised by TLC and NMR spectroscopy.


Subject(s)
Copper/chemistry , Deoxy Sugars/chemical synthesis , Pargyline/analogs & derivatives , Proline/chemistry , Propylamines/chemistry , Deoxy Sugars/chemistry , Ligands , Molecular Structure , Pargyline/chemistry , Stereoisomerism
10.
Carbohydr Res ; 484: 107775, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31430604

ABSTRACT

Stereo-defined 2-deoxy propargyl glycosides can be used for the synthesis of corresponding 1,4-disubstituted sugar derived triazoles by using only CuI and stereo-defined sugar azide derivatives. The click chemistry which involves copper (I) catalysed alkyne-azide 1,3-dipolar cycloaddition, was used to prepare a library of glycoconjugates mimics. Different sugar propargyl-2-deoxy-O-α-d-glycopyranoside derivatives and ß-glycopyranosyl azide derivatives were coupled using catalyst CuI to yield triazole glycoconjugates. The catalyst CuI (2.5 eq.) in CH3CN was found to be most efficient for the synthesis of 1,4-disubstituted triazole scaffolds affording up to 94% of optimized yield and with retention of the anomeric configuration of the starting glycosides. The key feature of this methodology is the absence of sodium l-ascorbate/ascorbic acid which is most active substrate of current research with strong potential for click reactions. In this article, the library of novel stereoselective deoxy sugar derived triazole glycoconjugates have been synthesized and structures were determined by the 1H, 13C & 2D NMR spectroscopy.


Subject(s)
Click Chemistry/methods , Glycoconjugates/chemical synthesis , Triazoles/chemical synthesis , Carbohydrate Conformation , Catalysis , Copper/chemistry , Cycloaddition Reaction , Glycoconjugates/chemistry , Magnetic Resonance Spectroscopy , Triazoles/chemistry
11.
Cell Death Dis ; 9(12): 1142, 2018 11 15.
Article in English | MEDLINE | ID: mdl-30442925

ABSTRACT

Radiation-induced bystander effect (RIBE) is a poorly understood phenomenon wherein non-targeted cells exhibit effects of radiation. We have reported that cell-free chromatin (cfCh) particles that are released from dying cells can integrate into genomes of surrounding healthy cells to induce DNA damage and inflammation. This raised the possibility that RIBE might be induced by cfCh released from irradiated dying cells. When conditioned media from BrdU-labeled irradiated cells were passed through filters of pore size 0.22 µm and incubated with unexposed cells, BrdU-labeled cfCh particles could be seen to readily enter their nuclei to activate H2AX, active Caspase-3, NFκB, and IL-6. A direct relationship was observed with respect to activation of RIBE biomarkers and radiation dose in the range of 0.1-0 Gy. We confirmed by FISH and cytogenetic analysis that cfCh had stably integrated into chromosomes of bystander cells and had led to extensive chromosomal instability. The above RIBE effects could be abrogated when conditioned media were pre-treated with agents that inactivate cfCh, namely, anti-histone antibody complexed nanoparticles (CNPs), DNase I and a novel DNA degrading agent Resveratrol-copper (R-Cu). Lower hemi-body irradiation with γ-rays (0.1-50 Gy) led to activation of H2AX, active Caspase-3, NFκB, and IL-6 in brain cells in a dose-dependent manner. Activation of these RIBE biomarkers could be abrogated by concurrent treatment with CNPs, DNase I and R-Cu indicating that activation of RIBE was not due to radiation scatter to the brain. RIBE activation was seen even when mini-beam radiation was delivered to the umbilical region of mice wherein radiation scatter to brain was negligible and could be abrogated by cfCh inactivating agents. These results indicate that cfCh released from radiation-induced dying cells are activators of RIBE and that it can be prevented by treatment with appropriate cfCh inactivating agents.


Subject(s)
Chromatin/genetics , Inflammation/drug therapy , Radiation Injuries/drug therapy , Resveratrol/pharmacology , Animals , Bystander Effect/drug effects , Bystander Effect/radiation effects , Caspase 3/genetics , Cell-Free System/drug effects , Cell-Free System/radiation effects , Chromatin/drug effects , Chromatin/radiation effects , Copper/pharmacology , Culture Media, Conditioned/pharmacology , DNA Damage/radiation effects , Deoxyribonuclease I/genetics , Disease Models, Animal , Gamma Rays/adverse effects , Histones/genetics , Humans , Inflammation/genetics , Inflammation/pathology , Interleukin-6/genetics , Mice , NF-kappa B/genetics , Radiation Injuries/genetics , Radiation Injuries/pathology
12.
Carbohydr Res ; 457: 51-55, 2018 Mar 02.
Article in English | MEDLINE | ID: mdl-29422121

ABSTRACT

Glucal with different alcohols can be converted into the corresponding 2-deoxy glycosides without Ferrier rearrangement in high yield by treatment with eco friendly transition metal based catalysts [CuCl3·2H2O-NaI (A) or CeCl3·7H2O-NaI (B)] and chiral amine ligand L-proline at various reaction conditions which were optimized for stereoselectivity. The catalyst CeCl3·7H2O-NaI (B) and ligand L-proline in toluene, was found to be much more efficient and high atom economic for the stereoselective glycosidation of propargyl alcohol with glucal, afforded exclusively α-2-deoxy propargyl glycoside in 98% optimized yield. The ligand L-proline was used for the first time in stereoselective glycosidation of α-2-deoxy glycosides involving glucal and alcohols.


Subject(s)
Cerium/chemistry , Glycosides/chemistry , Proline/chemistry , Catalysis , Glycosylation , Stereoisomerism
13.
BMC Mol Biol ; 18(1): 21, 2017 08 09.
Article in English | MEDLINE | ID: mdl-28793862

ABSTRACT

BACKGROUND: We have recently reported that cell-free DNA (cfDNA) fragments derived from dying cells that circulate in blood are biologically active molecules and can readily enter into healthy cells to activate DNA damage and apoptotic responses in the recipients. However, DNA is not conventionally known to spontaneously enter into cells or to have any intrinsic biological activity. We hypothesized that cellular entry and acquisition of biological properties are functions of the size of DNA. RESULTS: To test this hypothesis, we generated small DNA fragments by sonicating high molecular weight DNA (HMW DNA) to mimic circulating cfDNA. Sonication of HMW DNA isolated from cancerous and non-cancerous human cells, bacteria and plant generated fragments 300-3000 bp in size which are similar to that reported for circulating cfDNA. We show here that while HMW DNAs were incapable of entering into cells, sonicated DNA (sDNA) from different sources could do so indiscriminately without heed to species or kingdom boundaries. Thus, sDNA from human cells and those from bacteria and plant could enter into nuclei of mouse cells and sDNA from human, bacterial and plant sources could spontaneously enter into bacteria. The intracellular sDNA associated themselves with host cell chromosomes and integrated into their genomes. Furthermore, sDNA, but not HMW DNA, from all four sources could phosphorylate H2AX and activate the pro-inflammatory transcription factor NFκB in mouse cells, indicating that sDNAs had acquired biological activities. CONCLUSIONS: Our results show that small fragments of DNA from different sources can indiscriminately enter into other cells across species and kingdom boundaries to integrate into their genomes and activate biological processes. This raises the possibility that fragmented DNA that are generated following organismal cell-death may have evolutionary implications by acting as mobile genetic elements that are involved in horizontal gene transfer.


Subject(s)
DNA/genetics , Gene Transfer, Horizontal , Animals , Cell Line , Cell-Free Nucleic Acids/chemistry , Cell-Free Nucleic Acids/genetics , Chromosomes/chemistry , Chromosomes/genetics , Chromosomes/metabolism , DNA/chemistry , DNA/metabolism , Fluorescent Antibody Technique , Histones/metabolism , Humans , Mice , Microscopy, Fluorescence , Molecular Weight , NF-kappa B/metabolism , Species Specificity
14.
Cell Death Discov ; 3: 17015, 2017.
Article in English | MEDLINE | ID: mdl-28580170

ABSTRACT

Bystander cells of the tumor microenvironment show evidence of DNA damage and inflammation that can lead to their oncogenic transformation. Mediator(s) of cell-cell communication that brings about these pro-oncogenic pathologies has not been identified. We show here that cell-free chromatin (cfCh) released from dying cancer cells are the key mediators that trigger both DNA damage and inflammation in the surrounding healthy cells. When dying human cancer cells were cultured along with NIH3T3 mouse fibroblast cells, numerous cfCh emerged from them and rapidly entered into nuclei of bystander NIH3T3 cells to integrate into their genomes. This led to activation of H2AX and inflammatory cytokines NFκB, IL-6, TNFα and IFNγ. Genomic integration of cfCh triggered global deregulation of transcription and upregulation of pathways related to phagocytosis, DNA damage and inflammation. None of these activities were observed when living cancer cells were co-cultivated with NIH3T3 cells. However, upon intravenous injection into mice, both dead and live cells were found to be active. Living cancer cells are known to undergo extensive cell death when injected intravenously, and we observed that cfCh emerging from both types of cells integrated into genomes of cells of distant organs and induced DNA damage and inflammation. γH2AX and NFκB were frequently co-expressed in the same cells suggesting that DNA damage and inflammation are closely linked pathologies. As concurrent DNA damage and inflammation is a potent stimulus for oncogenic transformation, our results suggest that cfCh from dying cancer cells can transform cells of the microenvironment both locally and in distant organs providing a novel mechanism of tumor invasion and metastasis. The afore-described pro-oncogenic pathologies could be abrogated by concurrent treatment with chromatin neutralizing/degrading agents suggesting therapeutic possibilities.

15.
Curr Pharm Des ; 23(8): 1175-1187, 2017.
Article in English | MEDLINE | ID: mdl-27817745

ABSTRACT

The burden of cardio-vascular and other age-related non-communicable diseases are rapidly increasing worldwide. Majority of these chronic ailments are curable, if diagnosed at early stages. Candidate biomarkers of early detection are therefore essential for identification of high-risk individuals, prompt and accurate disease diagnosis, and to monitor therapeutic response. The functional significance of circulating nucleic acids that recapitulate specific disease profiles is now well established. But subtle changes in DNA sequence may not solely reflect the differentiation of gene expression patterns observed in diverse set of diseases as epigenetic phenomena play a larger role in aetiology and patho-physiology. Unlike genetic markers, knowledge about the diagnostic utility of circulating epigenetic signatures: methylated DNA; micro RNA and modified histones are deficient. Characterization of these novel entities through omics-based molecular technologies might prompt development of a range of laboratory-based strategies, thereby accelerating their broader translational purpose for early disease diagnosis, monitoring therapeutic response and drug resistance. However, largest opportunity for innovation lies in developing point-of-care tests with accurate diagnostic and higher prognostic score that is applicable for screening of high-risk populations.


Subject(s)
Cardiovascular Diseases/blood , Cardiovascular Diseases/genetics , Epigenesis, Genetic , Epigenomics , Age Factors , Biomarkers/blood , Cardiovascular Diseases/diagnosis , Chronic Disease , Humans
16.
Nat Prod Res ; 31(7): 749-757, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27756147

ABSTRACT

Two new compounds 1 (Methyl 26-di-deoxy-6-methyl-ß-D-allohexopyranoside) and 3 (3, 11, 12, 20 tetra-O-acetyl-pregn-5-ene-14ß-ol) have been isolated from the chloroform-soluble extract of the whole plant of Marsdenia roylei (family: Asclepiadaceae) and their structures were determined by 1D, 2D NMR and ESI-MS as well as by chemical modification. We have calculated the molecular geometries, local reactivity descriptors by the density functional theory with B3LYP functional with basis set 6-311G+(d,2p) of 1, 3 and 4 (deacylated 3). The 1H and 13C NMR chemical shifts of 1, 3 and 4 were calculated using Gauge-Including Atomic Orbital approach and these values are correlated with the experimental observations.


Subject(s)
Marsdenia/chemistry , Acylation , Chloroform/chemistry , Glucosides , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Structure , Plant Extracts/chemistry , Pregnenes , Quantum Theory , Spectrometry, Mass, Electrospray Ionization
17.
Eur J Pharm Sci ; 89: 94-104, 2016 Jun 30.
Article in English | MEDLINE | ID: mdl-27108116

ABSTRACT

Tinidazole is a versatile anti-amoebic and anti-anaerobic drug used in treatment of intestinal infection. The aim of present study was to develop and evaluate a guar gum based novel target release Tinidazole matrix tablet in animal models and healthy human volunteer using Gamma Scintigraphy technique. Anti-anaerobic and anti-protozoal activity of the developed formulation was studied in vitro against Bacteroides fragilis and Dentamoeba fragilis. Tinidazole was successful radiolabelled with (99m)Tc-pertechnetate using stannous chloride as a reducing agent and stable up to 24h in normal saline and serum. Radiolabeled formulation was evaluated in 6 Newzealand white rabbits by gamma Scintigraphy in static manner up to 24h for its retention in gastrointestinal tract (GIT). Similar set of study was conducted in 12 healthy human volunteers for similar objective Scintigraphy images of healthy human volunteer showed retention of optimized formulations in stomach up to 60min, from where it moved to duodenum further and reached ileum in around 5h. However, initiation of drug release was observed from intestine at 7h. Complete dissociation and release of drug was observed at 24h in colon due to anaerobic microbial rich environment. Results drawn from Scintigraphy images indicate that radiolabeled (99m)Tc-Tinidazole tablet transit through upper part of GI without disintegration. Hence the developed matrix tablet may have a role in treatment of intestinal infection caused by anaerobic bacteria.


Subject(s)
Bacteria, Anaerobic/drug effects , Bacterial Infections/drug therapy , Gastrointestinal Tract/microbiology , Tinidazole/therapeutic use , Adult , Bacteroides fragilis/drug effects , Chemistry, Pharmaceutical , Drug Delivery Systems/methods , Galactans/ultrastructure , Gamma Rays , Humans , Male , Mannans/ultrastructure , Plant Gums , Radionuclide Imaging/methods , Tablets/therapeutic use , Young Adult
18.
Cell Biol Int ; 40(2): 166-76, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26431927

ABSTRACT

Extra-pulmonary tuberculosis is often an underrated illness. Recent clinical studies have pointed out that lymphocyte homeostasis is dramatically disturbed as revealed through a series of signs and symptoms. Lymphocytes, the known effector cells of our immune system, play an important role in providing immunologic resistance against Mycobacterium infection. It is important to have quantitative insights into the lifespan of these cells; therefore, we aimed to study the precise effect of gastrointestinal tuberculosis infection on peripheral blood lymphocyte subpopulations and function. Our results indicated that gastrointestinal tuberculosis could increase mitochondrial oxidative stress, lower mitochondrial DNA copy number, promote nuclear DNA damage and repair response, decrease mitochondrial respiratory chain enzyme activities, and upregulate Bcl-2 and caspase-3 gene expression in lymphocytes. We further revealed that Mycobacterium infection induces autophagy for selective sequestration and subsequent degradation of the dysfunctional mitochondrion before activating cellular apoptosis in the peripheral lymphocyte pool. Together, these observations uncover a new role of mitochondrial-nuclear crosstalk that apparently contributes to lymphocyte homeostasis in gastrointestinal tuberculosis infection.


Subject(s)
Lymphocytes/metabolism , Mitochondria/metabolism , Oxidative Stress/physiology , Tuberculosis/blood , Apoptosis/physiology , Autophagy/physiology , Case-Control Studies , Caspase 3/metabolism , DNA Damage , DNA Repair , DNA, Mitochondrial/metabolism , Gastrointestinal Diseases/blood , Gastrointestinal Diseases/genetics , Gastrointestinal Diseases/microbiology , Gastrointestinal Diseases/pathology , Homeostasis , Humans , Reactive Oxygen Species/metabolism , Tuberculosis/genetics , Tuberculosis/pathology
19.
Front Biosci (Landmark Ed) ; 21(4): 769-93, 2016 01 01.
Article in English | MEDLINE | ID: mdl-26709805

ABSTRACT

Mitochondria play a fundamental role in regulating a variety of complex metabolic processes to maintain adequate energy balance for cellular existence. To orchestrate these functions, an undisturbed mitochondrial dynamics is imperative through a set of tightly guided mechanisms. Interference in key signature processes by several genetic, epigenetic and age-linked factors triggers mitochondrial dysfunction through decrease in mitochondrial biogenesis, reduced mitochondrial content, aberrant mtDNA mutations, increased oxidative stress, deficient mitophagy, energy dysfunction, decrease in anti oxidant defense and impaired calcium homeostasis. Mitochondrial dysfunction is widely implicated in origin and development of various age associated degenerative human ailments including metabolic syndromes, cardiovascular diseases, cancer, diabetes and neurodegenerative disorders. The present review revisits the mitochondrial anomalies involved in aetiology of different human diseases and also highlights the translational significance of nano-vectors aimed for selective mitochondrial engineering which might pave way for development of novel therapeutics.


Subject(s)
Aging/pathology , Mitochondrial Diseases/pathology , Epigenesis, Genetic , Humans , Mitochondrial Diseases/genetics , Mitophagy , Oxidation-Reduction , Signal Transduction
20.
Nat Prod Res ; 30(2): 199-205, 2016.
Article in English | MEDLINE | ID: mdl-26181638

ABSTRACT

The structures of two novel steroidal derivatives (1 and 4) were elucidated. Steroidal derivatives namely fologenin (1) and hoyagenin (4) have been isolated from chloroform-soluble extract of the whole plant of Hoya longifolia (family: Asclepiadaceae), and their structures were determined by using (1)H NMR, (13)C NMR, (1)H-(1)H COSY and FAB-MS techniques as well as chemical degradation and derivatisation.


Subject(s)
Apocynaceae/chemistry , Plant Extracts/chemistry , Steroids/chemistry , Chloroform/chemistry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Steroids/isolation & purification
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