DNA interactive property of poly-L-lysine induces apoptosis in MCF-7 cells through DNA interaction.

Poly-L-lysine (PLL) is known to be an encapsulating agent in drug formulation and delivery. PLL also has apoptotic and antiproliferative activities that enable blocking of the tumorigenesis process. However, the dose-selective activities of PLL in exerting apoptosis against cancer are unclear. Therefore, this study has been designed to explore the potential role and dose of PLL in apoptosis, if any. For this, PLL was administered at several doses in cancer cell lines and was found to be more potent against MCF-7 cells. PLL causes mitochondria-mediated apoptotic death through the upregulation of cleaved caspase-3. To investigate the mechanism responsible for this activity, we have analyzed if PLL could have the DNA interactive property or not. For this, molecular docking analysis was carried out to prove whether it has the property to bind with DNA or not. Studies have revealed that PLL is a potent DNA binder and it probably performs such apoptotic activities through the binding of cellular DNA early in an exposure. Simultaneous upregulation of both ROS-mediated stress and also in key protein expressions like Î³-H2AX could also help us to confirm that PLL induces apoptosis through DNA interaction. This finding leads us to believe that PLL could play an interfering role with other chemotherapeutic compounds when used as a drug-coating material as it exerts an apoptotic effect on cancer cells, which should be avoided by using a much lower concentration.

Photodynamic activity attained through the ruptured π-conjugation of pyridyl groups with a porphyrin macrocycle: synthesis and the photophysical and photobiological evaluation of 5-mono-(4-nitrophenyl)-10,15,20-tris-[4-(phenoxymethyl)pyridine]-porphyrin and its Zn(ii) complex.

This article compares a reported hydrophobic and photobiologically inert porphyrin synthon, (NPh)TPyP, bearing a single meso-4-nitrophenyl group and three meso-pyridyl groups (A3B type) with a new photobiologically active metal-free porphyrin, P3N, and its zinc-complex, P3NZn, which bear a meso-4-nitrophenyl group along with three distal pyridyl groups. Both P3N and P3NZn experience ruptured π-conjugation with the porphyrin macrocycle and attain hydrophilicity, as indicated via density functional theory (DFT) calculations, becoming photobiologically active under in vitro conditions. The non-invasive photodynamic activity (PDA) predominantly shown by the zinc-complex P3NZn (with higher hydrophilicity) towards KRAS-mutated human lung-cancer cells (A549) was studied. The results indicate the existence of intracellular singlet oxygen inflicted anticancer PDA, which is apparent through the upregulation of intracellular reactive oxygen species (ROS) and the downregulation of both intracellular superoxide dismutase (SOD) and intracellular reduced glutathione (GSH) levels. The trends obtained from both SOD and GSH assays were indicators of therapeutic defence against oxidative stress via neutralizing superoxide anions (SOA).

Socioeconomic gradient of lean diabetes in India: Evidence from National Family Health Survey, 2019-21.

Diabetes is a global public health challenge, particularly in India, affecting millions. Among diabetic patients, lean type 2 diabetes is a severe subtype with higher microvascular complication risks. While studies on the prevalence, variations and risk factors of diabetes are increasingly available, there has been limited research on the prevalence, variations, and socioeconomic disparities of lean diabetes in India. This study used NFHS-5 microdata, and lean diabetes is defined as those with a BMI level of under 25 and random blood glucose levels of over 200 or under diabetic medication. Descriptive and multivariate analyses were conducted to understand lean diabetes variations and related factors. Socioeconomic disparities were measured using concentration curves and the concentration index. The study unveiled important insights into lean diabetes in India. 8.2% of men and 6.0% of women had elevated blood glucose levels, indicating a significant diabetes burden. Notably, 2.9% of men and 2.4% of women were diagnosed with lean diabetes. Among type 2 diabetics, 52.56% of males and 43.57% of females had lean type 2 diabetes. Lean diabetes prevalence varied from 11.6% in the poorest quintile to 1.1% in the richest. The odds of lean type 2 diabetes among those in the poorest quintile was 6.7 compared to the richest quintile. The concentration index of lean type 2 diabetes was -0.42 for men and -0.39 for women, suggesting a disproportionate impact on lower socioeconomic groups. This study advances our understanding of the complex interplay between socioeconomic factors and lean type 2 diabetes in India. To address the rising burden of lean diabetes among lower socioeconomic strata, policymakers and healthcare professionals must prioritise initiatives enhancing healthcare access, promoting healthy lifestyles, and ensuring effective diabetes management. By addressing socioeconomic disparities and implementing interventions for vulnerable populations, India can reduce diabetes-related mortality and enhance its citizens' overall health.

Condurango-glycoside-A fraction of Gonolobus condurango induces DNA damage associated senescence and apoptosis via ROS-dependent p53 signalling pathway in HeLa cells.

Gonolobus condurango plant extract is used as an anticancer drug in some traditional systems of medicine including homeopathy, but it apparently lacks any scientific validation. Further, no detailed study is available to suggest whether condurango-glycoside-A (CGA), a major ingredient of condurango serves as a potent anticancer compound. Therefore, we investigated apoptosis-inducing ability of CGA against cervix carcinoma cells (HeLa). ß-galactosidase-activity and DNA damage were critically studied at different time points; while induced DNA-damage was observed at 9-12th hours, senescence of cells appeared at a later stage (18th hour after CGA treatment), implicating thereby a possible role of DNA damage in inducing pre-mature cell senescence. Concurrently, the number of cells undergoing apoptosis increased along with increase in reactive oxygen species (ROS) generation. Expression of p53 was also up-regulated, indicating that apoptosis could have been mediated through p53 pathway. DCHFDA (4',6-Diamidino-2-phenylindole dihydrochloride) assay, acridine orange/ethidium bromide staining and annexin V/PI assay results collectively confirmed that apoptosis was induced by increased ROS generation. Reduction in proliferation of cells was further evidenced by the cell cycle arrest at G0/G1 stage. Expression profiles of certain relevant genes and proteins like p53, Akt, Bcl-2, Bax, cytochrome c and caspase 3 also provided evidence of ROS mediated p53 up-regulation and further boost in Bax expression and followed by cytochrome c release and activation of caspase 3. Overall results suggest that CGA initiates ROS generation, promoting up-regulation of p53 expression, thus resulting in apoptosis and pre-mature senescence associated with DNA damage.

Ethanolic extract of Thuja occidentalis blocks proliferation of A549 cells and induces apoptosis in vitro.

OBJECTIVE: To study the possible anticancer and antiproliferative activities of ethanolic leaf extract of Thuja occidentalis (TO) on A549 non-small lung carcinoma cells in vitro. METHODS: Cell viability was ascertained through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after deployment of TO in different doses. The half maximal inhibitory concentration (IC50) dose (282 µg/mL) was determined, and two other doses for dose-dependence study, one below the IC50 dose (IC35=188 µg/mL) and one above the IC50 dose (IC65=376 µg/mL) were selected. Bromodeoxyuridine (BrdU) incorporation assay and migration studies were performed to elucidate antiproliferative activity of the drug, if any. Fluorescence-activated cell sorting analysis after annexin V-fluorescein isothiocyanate and propidium iodide (annexin V-FITC-PI) dual staining method was done to ascertain early stage of apoptosis, if any. DNA fragmentation assay was done through Hoechst 33258 and acridine orange-ethidium bromide staining. DNA damage was quantified through comet assay. Bax-Bcl2 regulation and expression studies were performed through indirect enzyme-linked immunosorbent assay (ELISA). Caspase 3 activity was measured at gene level through reverse transcription-polymerase chain reaction (RT-PCR) analysis. Its activation at protein level was analyzed through indirect ELISA and Western blot analysis. RESULTS: TO demonstrated a dose-dependent decrease in viability of A549 cells after 24 h of exposure. Cell proliferation was reduced in a time-dependent manner of drug exposure as revealed from BrdU incorporation and migration studies. Annexin-V-FITC positivity of cells up to 11.72% as compared to the untreated control revealed early state of TO-induced apoptosis. Occurrence of comet tail and increased fluorescence of Hoechst after 24 h of drug exposure revealed significant DNA nick generation and chromatin condensation. Bax up-regulation and Bcl-2 down-regulation suitably altered ratio of Bax/Bcl-2 in favor of apoptosis. From RT-PCR, indirect ELISA and Western blot studies, caspase 3 activity was also found to be significantly increased along with cleaved poly ADP-ribose polymerase expression. CONCLUSION: Ethanolic leaf extract of TO demonstrated apoptotic and antiproliferative potentials against A549 cell line.

Chelidonine isolated from ethanolic extract of Chelidonium majus promotes apoptosis in HeLa cells through p38-p53 and PI3K/AKT signalling pathways.

OBJECTIVE: To evaluate the role of chelidonine isolated from ethanolic extract of Chelidonium majus in inducing apoptosis in HeLa cells and to assess the main signalling pathways involved. METHODS: Cells were initially treated with different concentrations of chelidonine for 48 h and the median lethal dose (LD50) value was selected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Morphological analysis of nuclear condensation and DNA damage and fragmentation were measured by 4',6-diamidino-2-phenylindole staining and comet assay. Further, reactive oxygen species (ROS) generation, cell cycle arrest and change in mitochondrial membrane potential were also examined and analyzed by flow cytometry. Evaluation of interaction of drug with CT DNA was investigated by circular dichroism (CD) spectral analysis to find any possible drug-CT DNA interaction. The mRNA and protein expressions of major signal proteins like p38, p53, protein kinase B (AKT), phosphatidylinositol 3-kinases (PI3K), Janus kinase 3 (JAK3), signal transducer and activator of transcription 3 (STAT3) and E6 and E7 oncoproteins as well as the pro-apoptotic genes and antiapoptotic genes were also estimated by reverse transcriptase-polymerase chain reaction and Western blotting. RESULTS: Based on LD(50) value (30 µg/mL) of chelidonine, three doses were selected, namely, 22.5 µg/mL (D1), 30.0 µg/mL (D2) and 37.5 µg/mL (D3). Results showed that chelidonine inhibited proliferation and induced apoptosis in HeLa cells through generation of ROS, cell cycle arrest at sub-G1 and G0/G1 stage, change in mitochondrial membrane potential and fragmentation of DNA. Results of CD spectra showed effective interaction between chelidonine and calf thymus DNA. Studies of signalling pathway revealed that chelidonine could efficiently induce apoptosis through up-regulation of expressions of p38, p53 and other pro-apoptotic genes and down-regulation of expressions of AKT, PI3K, JAK3, STAT3, E6, E7 and other antiapoptotic genes. CONCLUSION: Chelidonine isolated from Chelidonium majus efficiently induced apoptosis in HeLa cells through possible alteration of p38-p53 and AKT/PI3 kinase signalling pathways.

Mechanical dependency of the SARS-CoV-2 virus and the renin-angiotensin-aldosterone (RAAS) axis: a possible new threat.

Pathogens in our environment can act as agents capable of inflicting severe human diseases. Among them, the SARS-CoV-2 virus has recently plagued the globe and paralyzed the functioning of ordinary human life. The virus enters the cell through the angiotensin-converting enzyme-2 (ACE-2) receptor, an integral part of the renin-angiotensin system (RAAS). Reports on hypertension and its relation to the modulation of the RAAS are generating interest in the scientific community. This short review focuses on the SARS-CoV-2 infection's direct and indirect effects on our body through modulation of the RAAS axis. A patient having severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, which causes COVID-19 relates to hypertension as a pre-existing disease or develops it in a post-COVID scenario. Several studies on how SARS-CoV-2 modulates the RAAS axis indicate that it alters our body's physiological balance. This review seeks to establish a hypothesis on the mechanical dependency of SARS-CoV-2 and RAAS modulation in the human body. This study intends to impart ideas on drug development and designing by targeting the modulation of the RAAS axis to inactivate the pathogenicity of the SARS-CoV-2 virus. A systematic hypothesis can severely attenuate the pathogenicity of the dreadful viruses of the future.

An Anti-inflammatory Fe3 O4 -Porphyrin Nanohybrid Capable of Apoptosis through Upregulation of p21 Kinase Inhibitor Having Immunoprotective Properties under Anticancer PDT Conditions.

We report the influence of Fe3 O4 nanoparticles (NPs) on porphyrins in the development of photosensitizers (PSs) for efficient photodynamic therapy (PDT) and possible post-PDT responses for inflicting cancer cell death. Except for Au, most metal-based nanomaterials are unsuitable for clinical applications. The US Food and Drug Administration and other agencies have approved Feraheme and a few other iron oxide NPs for clinical use, paving the way for novel biocompatible immunoprotective superparamagnetic iron oxide nanohybrids to be developed as nanotherapeutics. A water-soluble nanohybrid, referred to here as E-NP, comprising superparamagnetic Fe3 O4 NPs functionalised with tripyridyl porphyrin PS was introduced through a rigid 4-carboxyphenyl linker. As a PDT agent, the efficacy of E-NP toward the AGS cancer cell line showed enhanced photosensitising ability as determined through in vitro photobiological assays. The cellular uptake of E-NPs by AGS cells led to apoptosis by upregulating ROS through cell-cycle arrest and loss of mitochondrial membrane potential. The subcellular localisation of the PSs in mitochondria stimulated apoptosis through upregulation of p21, a proliferation inhibitor capable of preventing tumour development. Under both PDT and non-PDT conditions, this nanohybrid can act as an anti-inflammatory agent by decreasing the production of NO and superoxide ions in murine macrophages, thus minimising collateral damage to healthy cells.

Poly-l-Lysine inhibits VEGF and c-Myc mediated tumor-angiogenesis and induces apoptosis in 2D and 3D tumor microenvironment of both MDA-MB-231 and B16F10 induced mice model.

Cancer is a widespread disease that has shown promising mortality worldwide. Our previous study has been shown the efficacy of Poly-l-lysine (PLL) as a promising cytotoxic effect against cancer cells. However, exact-mechanism of PLL in 3D physiological relevant tumor-microenvironment and against tumor-angiogenesis has never been analysed. In this study, we have investigated apoptotic efficacy of PLL, if any in opposition to proliferative aggressive cancer cell MDA-MB-231 both 2D and-3D cell culture conditions. Furthermore, PLL was administered in B16F10 murine melanoma cells induced BALB/c mice model. The study has been designed through transcription and translation level of PLL-induced tumor-angiogenesis and apoptotic gene-expression modulation level and various relevant histological studies in comparison with untreated control. Studies have shown anti-proliferative and anti-tumor angiogenic efficacy of PLL better in in-vitro 3D tumor-microenvironment against MDA-MB-231 breast cancer cells. Furthermore, in-vivo model, PLL was found to suppress tumorigenesis process at minimum dose. PLL found to induce apoptosis through-upregulation of cytosolic-cytochrome-C, caspase-3 and PARP activations when administered in B16F10 induced in-vivo tumor. In blocking proliferation and tumor-angiogenesis, PLL was found to be effective as it significantly downregulated activity of VEGF, VEGFR2, Ki-67 and c-Myc expression. As PLL blocked tumor progression and induced DNA-break, also upregulated apoptotic process and recovered tissue architecture as revealed from histological study in comparison with untreated control. Overall PLL was found to be a promising anti-tumor angiogenic and anti-proliferative drug that was effective both in in-vitro breast cancer 3D tumor-microenvironment and in-vivo metastatic-mice-model.

meso-Thiophenium Porphyrins and Their Zn(II) Complexes: A New Category of Cationic Photosensitizers.

A new category of cationic meso-thiophenium porphyrins are introduced as possible alternatives to the popular meso-pyridinium porphyrins. Combinations of cationic porphyrins bearing meso-2-methylthiophenium and meso-4-hydroxyphenyl moieties T2(OH)2M (A2B2 type) and T(OH)3M (AB3 type) along with their zinc(II) complexes T2(OH)2MZn and T(OH)3MZn, are reported. The increase in the number of thienyl groups attached to the meso-positions of the porphyrin derivatives (A2B2 frame) has been shown to impart longer fluorescence lifetimes and stronger photocytotoxicity toward A549 lung cancer cells, as evident with T2(OH)2M and its corresponding diamagnetic metal complex T2(OH)2MZn. The photoactivated T2(OH)2MZn imparts an early stage reactive oxygen species (ROS) upregulation and antioxidant depletion in A549 cells and contributes to the strongest oxidative stress-induced cell death mechanism in the series. The DFT calculations of the singlet-triplet energy gap (ΔE) of all the four hydrophilic thiophenium porphyrin derivatives establish the potential applicability of these cationic photosensitizers as PDT agents.

Dual activity of amphiphilic Zn(II) nitroporphyrin derivatives as HIV-1 entry inhibitors and in cancer photodynamic therapy.

Two Zn(II) nitro porphyrin derivatives bearing combinations of meso-4-nitrophenyl and meso-4-methylpyridinium moieties and their free-base precursors were synthesized through one-pot microwave process, purified and characterized. The biological activity of these nitroporphyrins was assessed under both photodynamic and non-photodynamic conditions to correlate their structure-activity relationship (SAR). Unlike, the free-base precursors, Zn(II) complexes of these nitroporphyrins displayed nearly complete inhibition in the entry of lentiviruses such as HIV-1 and SIVmac under non-photodynamic conditions. In addition, the Zn(II) complexes also exhibited a higher in vitro photodynamic activity towards human lung cancer cell-line A549 than their free-base precursors. Our results strongly suggest that incorporation of Zn(II) has improved the antiviral and anticancer properties of the nitroporphyrins. To the best of our knowledge, this is the first report demonstrating the dual activity of nitroporphyrin-zinc complexes as antiviral and anti-cancer, which will aid in their development as therapeutics in clinics.

Induction of apoptosis, anti-proliferation, tumor-angiogenic suppression and down-regulation of Dalton's Ascitic Lymphoma (DAL) induced tumorigenesis by poly-l-lysine: A mechanistic study.

PURPOSE: The present study, attempts to validate the molecular mechanism(s) of Poly-l-lysine (PLL) induced apoptosis, anti-proliferative and anti-tumorigenic properties in in-vitro HUVECs cells and Dalton's Ascitic Lymphoma (DAL) and in in-vivo DAL cell bearing BALB/c mice model. MATERIALS AND METHODS: The cell proliferation assay and morphological assay was carried out using the MTT assay and Giemsa staining method. The antitumor activity of PLL was evaluated in BALB/c mice at 20 and 40 mg/kg/b.w doses for 21 days for DAL solid tumor model. Several tumor evaluation endpoints, hematological and biochemical parameters were estimated. Additionally, the tumor apoptosis, anti-proliferative and anti-tumor angiogenesis effects were assessed using western blots and immunohistochemistry. RESULTS: PLL significantly decreased cell proliferation in in-vitro HUVECs and DAL cells without significant effects on normal cell growth. PLL also induced alteration in cellular morphology in DAL cells. Therafter, in the BALB/c mouse model, PLL had noticeable inhibition in DAL-induced tumorigenesis. This inhibition was evident through reduced solid tumor volume and weight versus the control group. However, PLL promoted tumor apoptosis and suppressed cell-proliferation and tumor-angiogenesis. PLL also increased hematological markers significantly compared to 5-flurouracil (5-FU). The amount of TdT in the nuclei of DAL cells in mice treated with PLL was significantly increased while in contrast decreases of anti-apoptotic protein Bcl-2 expression were observed. PLL also significantly upregulated the pro-apoptotic protein Bax and activated caspase-3. Measurable decreases of cyclin-D1 were observed through PLL treatments, an indicator of cell-cycle arrest. These studies also indicate PLL's induction and anti-proliferative effects through suppression of the c-Myc and Ki-67 proliferation-indices. Additionally, PLL inhibited tumor-angiogenesis through suppression of VEGF and CD34 protein expression levels and reduction ofmicrovesseldensityversus similar parameters in tumors from control mice. CONCLUSION: The present study offers opportunities and hopes for possible anti-tumortherapies with PLL in the near future and warrants further formulation developments.

Benzamide porphyrins with directly conjugated and distal pyridyl or pyridinium groups substituted to the porphyrin macrocycles: Study of the photosensitising abilities as inducers of apoptosis in cancer cells under photodynamic conditions.

Amphiphilic porphyrin photosensitisers (PSs) having combinations of directly substituted pyridyl group(s) at the meso-position of a porphyrin macrocycle, and/or indirectly linked pyridyl groups as benzamide derivatives are reported. The compounds 5,10,15,20-tetrakis-(4-pyridylbenzamide)porphyrin (A.2), 5,10,15,20-tetra[N-(pyridine-4-yl)benzamidium] porphyrin (A.3), 5-mono-(4-pyridyl)-10,15,20-tris-(4-pyridylbenzamide)porphyrin (B.2) and 5-mono-(4-methylpyridinium)-10,15,20-tris-(4-pyridiniumbenzamide)porphyrin (B.3) were synthesised. The compounds were successfully characterised through UV-Vis, Emission, 1H NMR, and ESI-HRMS techniques. To evaluate the effect of this combination of directly conjugated and non-conjugated pyridyl/cationic pyridinium groups on the porphyrin macrocycle, the efficacy of the synthesised compounds was compared to a known standard 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin (TMPyP). These compounds show better efficacy (IC50's ranging between 0.66±0.04µM to 3.71±1.01µM) against A549 (human epithelial adenocarcinoma lung cancer) cell line under in vitro photodynamic conditions in comparison to MDA-MB-231 (breast cancer) (IC50's ranging between 3.7±0.087µM to 12.1±0.12µM) and Pa-1 (ovarian cancer) (IC50's ranging between 17.9±0.01µM to 42.45±0.02µM) cell lines. It was found that B.3, having a pyridinium group attached to the meso-position of the macrocycle along with three distal cationic pyridinium groups, independent of the porphyrinic electron delocalisation cycle, showed better photocytotoxic efficacy (IC50=0.66±0.04µM, A549 lung cancer cell line) and higher potential to promote apoptosis and hence better efficacy as PS towards cancer photodynamic therapy (PDT). The PDT activity of B.3 was further verified and established by various biological assays, viz. Annexin V assay, cell cycle assay, and reactive oxygen species (ROS) activity assay.

A pentanoic acid derivative targeting matrix metalloproteinase-2 (MMP-2) induces apoptosis in a chronic myeloid leukemia cell line.

Depending on our previous observations, some compounds of pentanoic acid were designed and synthesized. Characterization of the synthesized compounds was done by mass, NMR and IR spectroscopy as well as elemental analysis. Among the synthesized molecules, (2S)-5-oxo-2-[(nitrobenzene-4-yl sulfonyl) amino]-5-(pentylamino) pentanoic acid (Cpd 11) was found as a lead and potent inhibitor of matrix metalloproteinase-2 (MMP-2). Molecular modeling and enzyme inhibition studies were done to confirm the interaction or inhibitory potential of this compound. Thereafter, the biological screening was done through cytotoxicity, anti-invasion and apoptosis-related assays. Docking analysis revealed that Cpd 11 interacted with the target molecule MMP-2 and with MMP-9. However, enzyme inhibition assay showed 3-fold MMP-2 inhibition compared to MMP-9. Cytotoxicity assay showed the inhibitory potential of Cpd 11 against K562 cell line having IC50 value of 17.9 ± 0.01 µM after 48 h of incubation. The cell death was apoptotic in nature as revealed from the annexin V and sub-G1 cell cycle arrest assay. Besides this, Cpd 11 also exhibited dose dependent anti-invasive activity into K562 cell line. On the other hand, flow cytometry and western blot data revealed Cpd 11 induced downregulation of MMP-2 in K562 cell line after 48 h of incubation that might be linked with the anti-invasive and apoptotic activity furthermore. Therefore, the overall results validated each method and make this molecule as a potent MMP-2 inhibitor that blocked the invasion and could bring apoptosis at later stages in K562 cells sparing the normal ones.

Arylsulfonamides and selectivity of matrix metalloproteinase-2: An overview.

Uncontrolled regulation of specific metalloenzymes plays important roles in several diseases like tumor metastasis and inflammation. Therefore, selective metalloenzyme inhibition may be a potential target for drug design and development. Matrix metalloproteinase inhibitors (MMPIs) opened up a new horizon as the possible treatment of arthritis, cancer, and emphysema. However, due to adverse effects and poor pharmacokinetics, first generation MMPIs failed in clinical trials. Therefore, development of potential and selective MMPIs is still in demand. Moreover, the flexibility of the enzyme S1' pocket is variable in length and shape making the designing approach more challenging. In this article, arylsulfonamides have been highlighted as potential and selective MMP-2 inhibitors through structure-activity relationships study. It may be postulated that sulfonamide moiety may provide better direction to the associated aryl group to accommodate the deep hydrophobic S1' pocket. Tetrahedral geometry of the sulfonyl function may be favorable than planar carboxyl function regarding the interaction between the aryl group and S1' pocket. Hydroxamates may impart higher inhibition than corresponding carboxylates due to additional hydrogen bonding. Moreover, MMP-2 selectivity is not only dependent on zinc binders but also on the aryl functions directed towards S1 and S2' pockets. Therefore, this review may help in designing potential and selective MMP-2 inhibitors.

Anti-malarial Drug Design by Targeting Apicoplasts: New Perspectives.

OBJECTIVES: Malaria has been a major global health problem in recent times with increasing mortality. Current treatment methods include parasiticidal drugs and vaccinations. However, resistance among malarial parasites to the existing drugs has emerged as a significant area of concern in anti-malarial drug design. Researchers are now desperately looking for new targets to develop anti-malarials drug which is more target specific. Malarial parasites harbor a plastid-like organelle known as the 'apicoplast', which is thought to provide an exciting new outlook for the development of drugs to be used against the parasite. This review elaborates on the current state of development of novel compounds targeted againstemerging malaria parasites. METHODS: The apicoplast, originates by an endosymbiotic process, contains a range of metabolic pathways and housekeeping processes that differ from the host body and thereby presents ideal strategies for anti-malarial drug therapy. Drugs are designed by targeting the unique mechanism of the apicoplasts genetic machinery. Several anabolic and catabolic processes, like fatty acid, isopenetyl diphosphate and heme synthess in this organelle, have also been targeted by drugs. RESULTS: Apicoplasts offer exciting opportunities for the development of malarial treatment specific drugs have been found to act by disrupting this organelle's function, which wouldimpede the survival of the parasite. CONCLUSION: Recent advanced drugs, their modes of action, and their advantages in the treatment of malaria by using apicoplasts as a target are discussed in this review which thought to be very useful in desigining anti-malarial drugs. Targetting the genetic machinery of apicoplast shows a great advantange regarding anti-malarial drug design. Critical knowledge of these new drugs would give a healthier understanding for deciphering the mechanism of action of anti-malarial drugs when targeting apicoplasts to overcome drug resistance.

Quercetin Down-regulates IL-6/STAT-3 Signals to Induce Mitochondrial-mediated Apoptosis in a Nonsmall- cell Lung-cancer Cell Line, A549.

OBJECTIVES: Quercetin, a flavonoid compound, has been reported to induce apoptosis in cancer cells, but its anti-inflammatory effects, which are also closely linked with apoptosis, if any, on non-small-cell lung cancer (NSCLC) have not so far been critically examined. In this study, we tried to determine if quercetin had any demonstrable anti-inflammatory potential, which also could significantly contribute to inducing apoptosis in a NSCLC cell line, A549. METHODS: In this context, several assays, including cytotoxicity, flow cytometry and fluorimetry, were done. Gene expression was analyzed by using a western blot analysis. RESULTS: Results revealed that quercetin could induce apoptosis in A549 cells through mitochondrial depolarization by causing an imbalance in B-cell lymphoma 2/ Bcl2 Antagonist X (Bcl2/Bax) ratio and by down-regulating the interleukine-6/signal transducer and activator of transcription 3 (IL-6/STAT3) signaling pathway. An analysis of the data revealed that quercetin could block nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activity at early hours, which might cause a down-regulation of the IL-6 titer, and the IL-6 expression, in turn, could inhibit p-STAT3 expression. Down-regulation of both the STAT3 and the NF-κB expressions might, therefore, cause down-regulation of Bcl2 activity because both are major upstream effectors of Bcl2. Alteration in Bcl2 responses might result in an imbalance in the Bcl2/Bax ratio, which could ultimately bring about mitochondria mediated apoptosis in A549 cells. CONCLUSION: Overall, the finding of this study indicates that a quercetin induced anti-inflammatory pathway in A549 cells appeared to make a significant contribution towards induction of apoptosis in NSCLC and, thus, may have a therapeutic use such as a strong apoptosis inducer in cancer cells.

Anti-lung cancer potential of pure esteric-glycoside condurangogenin A against nonsmall-cell lung cancer cells in vitro via p21/p53 mediated cell cycle modulation and DNA damage-induced apoptosis.

BACKGROUND: Marsdenia condurango (condurango) is a tropical woody vine native to South America. Our earlier study was limited to evaluation of anti-cancer potentials of crude condurango extract and its glycoside-rich components in vitro on lung cancer. OBJECTIVE: This study aims at evaluating the effect of the single isolated active ingredient condurangogenin A (ConA; C32H42O7) on A549, H522 and H460-nonsmall-cell lung cancer cells. MATERIALS AND METHODS: ConA was isolated by column chromatography and analyzed by mass spectroscopy, Fourier transform infrared spectroscopy and proton-nuclear magnetic resonance. diphenyltetrazolium bromide assays were conducted on three cell-types using 6%-alcohol as control. Critical studies on cellular morphology, cell-cycle regulation, reactive oxygen species, mitochondrial membrane potential, and DNA-damage were made, and expressions of related signaling markers studied. RESULTS: As IC50 doses of ConA proved to be too high and toxic to both A549 and H522 cells, all experimental studies were carried out on H460 cells with the IC50 dose (32 µg/ml - 24 h). Cellular morphology revealed typical apoptotic features after ConA treatment. At early treatment hours (2 h-12 h), maximum cells were arrested at G0/G1 phase that could be correlated with reduced level of cyclin D1-CDK with p21 up-regulation. At 18 h - 24 h, sub G0/G1 cell population was increased gradually, as revealed from cytochrome-c release and caspase-3 activation, further confirming the apoptosis-inducing ability of ConA at later phases. Gradual increase of TUNEL-positive cells with significant modulation of mitochondria-dependent apoptotic markers at longer time-points would establish apoptosis-induction property of ConA, indicating its potential as a strong candidate for anti-cancer drug formulation. CONCLUSION: Further studies are warranted against other types of cancer cells and animal models before its possible human use.

Evaluation of chemopreventive potentials of ethanolic extract of Ruta graveolens against A375 skin melanoma cells in vitro and induced skin cancer in mice in vivo.

OBJECTIVE: Chemopreventive approach with natural products, particularly plants and plant-derived ones, is receiving increasing attention for their effective role against cancer without any palpable side effects. In this study, efficacy of ethanolic extract of Ruta graveolens (RG) on skin melanoma cells (A375) in vitro and on 7,12-dimethylbenz(a)anthracene (DMBA)-induced skin cancer in vivo has been tested in Swiss albino mice. METHODS: Studies on cell viability, apoptosis and autophagy induction were conducted in vitro. To check apoptosis, assays like alteration in mitochondrial membrane potential, annexin V-fluorescein isothiocyanate/propidium iodide assay and immunoblot were performed. Fluorescence microscopic and immunoblot assays were performed to confirm autophagy induction. The effects of RG were determined by evaluating body weight, tumor incidence, tumor volume and tumor burden in mice. Enzymatic and non-enzymatic antioxidant status was assessed. The role of some relevant signaling proteins was also analyzed. RESULTS: RG caused death of A375 cells through induction of caspase 3-mediated apoptosis and Beclin-1-associated autophagy. Moreover, RG administration (75 mg/kg body weight) which showed no acute or chronic toxicity, showed significant reduction in the skin tumor burden of DMBA-painted mice. RG also demonstrated potent anti-lipid peroxidative and antioxidant functions during the course of skin cancer induction by DMBA. CONCLUSION: Chemopreventive potential of RG was demonstrated from overall results of this study, indicating its possible use in therapeutic formulation of an effective drug to treat skin cancer.

Ethanolic Extract of Marsdenia condurango Ameliorates Benzo[a]pyrene-induced Lung Cancer of Rats: Condurango Ameliorates BaP-induced Lung Cancer in Rats.

OBJECTIVES: Condurango is widely used in various systems of complementary and alternative medicines (CAM) against oesophageal and stomach ailments including certain types of cancer. However, until now no systematic study has been conducted to verify its efficacy and dose with proper experimental support. Therefore, we examined if ethanolic extract of Condurango could ameliorate benzo[a]pyrene (BaP)-induced lung cancer in rats, in vivo to validate its use as traditional medicine. METHODS: Fifteen male and 15 female Sprague-Dawley (SD) rats were treated with 0.28 mg/kg of Sweet Bee Venom (SBV) (high-dosage group) and the same numbers of male and female SD rats were treated with 0.2 mL/kg of normal saline (control group) for 13 weeks. We selected five male and five female SD rats from the high-dosage group and the same numbers of male and female SD rats from the control group, and we observed these rats for four weeks. We conducted body-weight measurements, ophthalmic examinations, urinalyses and hematology, biochemistry, histology tests. RESULTS: A histological study revealed gradual progress in lung tissue-repair activity in Condurango-fed cancer-bearing rats, showing gradual tissue recovery after three months of drug administration. Condurango has the capacity to generate reactive oxygen species (ROS), which may contribute to a reduction in anti-oxidative activity and to an induction of oxidative stress-mediated cancer cell-death. Condurango-activated pro-apoptotic genes (Bax, caspase-3, caspase-9, p53, cytochrome-c, apaf-1, ICAD and PARP) and down-regulated antiapoptotic-Bcl-2 expression were noted both at mRNA and protein levels. Studies on caspase-3 activation and PARP cleavage by western blot analysis revealed that Condurango induced apoptosis through a caspase-3-dependent pathway. CONCLUSION: The anticancer efficacy of an ethanolic extract of Condurango for treating BaP-induced lung cancer in rats lends support for its use in various traditional systems of medicine.