Therapeutic vs. Suprapharmacological Metformin Concentrations: Different Effects on Energy Metabolism and Mitochondrial Function in Skeletal Muscle Cells .

Metformin is an oral antidiabetic agent that has been widely used in clinical practice for over 60 years, and is currently the most prescribed antidiabetic drug worldwide. However, the molecular mechanisms of metformin action in different tissues are still not completely understood. Although metformin-induced inhibition of mitochondrial respiratory chain Complex I and activation of AMP-activated protein kinase have been observed in many studies, published data is inconsistent.

In vitro models of insulin resistance: Mitochondrial coupling is differently affected in liver and muscle cells.

Mitochondrial dysfunction in diabetes is a widely studied topic, but inconsistency in literature data suggests a need for valid and reproducible models that will help to clarify this interaction. We aimed to establish insulin resistance models using chronic high insulin treatment in two cell types: myocytes and hepatocytes, characterise them in terms of mitochondrial function and compare them to the widely used palmitate-induced model of insulin resistance. We found that insulin lowered phosphorylation of Akt while not affecting cell viability, ROS production, mitochondrial morphology or respiration, and caused decrease in mitochondrial coupling only in muscle but not in liver cells.

Childhood maltreatment correlates with higher concentration of transforming growth factor beta (TGF-β) in adult patients with major depressive disorder.

Transforming growth factor beta (TGF-β), which has a role as a regulatory cytokine, has not been widely investigated in patients with major depressive disorder (MDD) who experienced childhood trauma. The aim of our study was to investigate the differences in circulating TGF-β levels between the patients with major depressive disorder (MDD) with and without child maltreatment (CM) history, and to compare them to the corresponding control subjects' groups (with or without CM). Blood samples were obtained from 55 patients, fulfilling DSM-IV-R criteria for a current MDD episode without psychotic symptoms, and 45 healthy controls, matched for age and gender.

Transcriptional block of AMPK-induced autophagy promotes glutamate excitotoxicity in nutrient-deprived SH-SY5Y neuroblastoma cells.

We investigated the role of autophagy, a controlled lysosomal degradation of cellular macromolecules and organelles, in glutamate excitotoxicity during nutrient deprivation in vitro. The incubation in low-glucose serum/amino acid-free cell culture medium synergized with glutamate in increasing AMP/ATP ratio and causing excitotoxic necrosis in SH-SY5Y human neuroblastoma cells. Glutamate suppressed starvation-triggered autophagy, as confirmed by diminished intracellular acidification, lower LC3 punctuation and LC3-I conversion to autophagosome-associated LC3-II, reduced expression of proautophagic beclin-1 and ATG5, increase of the selective autophagic target NBR1, and decreased number of autophagic vesicles.

AMP-activated protein kinase inhibits MPP+-induced oxidative stress and apoptotic death of SH-SY5Y cells through sequential stimulation of Akt and autophagy.

We investigated the interplay between the intracellular energy sensor AMP-activated protein kinase (AMPK), prosurvival kinase Akt, oxidative stress, and autophagy in the cytotoxicity of parkinsonian neurotoxin 1-methyl-4-phenyl piridinium (MPP+) towards SH-SY5Y human neuroblastoma cells. MPP+-mediated oxidative stress, mitochondrial depolarization, and apoptotic cell death were associated with rapid (within 2 h) activation of AMPK, its target Raptor, and prosurvival kinase Akt. Antioxidants N-acetylcysteine and butylated hydroxyanisole suppressed MPP+-induced cytotoxicity, AMPK, and Akt activation.

Tetravalent Metal Ion Guests in Polyoxopalladate Chemistry: Synthesis and Anticancer Activity of [MOPd(PO)] (M = Sn, Pb).

The first two examples of polyoxopalladates(II) (POPs) containing tetravalent metal ion guests, [MOPd(PO)] (M = Sn, Pb), have been prepared and structurally characterized in the solid state, solution, and gas phase. The interactions of the metal ion guests and the palladium-oxo shell were studied by theoretical calculations. The POPs were shown to possess anticancer activity by causing oxidative stress inducing caspase activation and consecutive apoptosis of leukemic cells.

Current Development of Metal Complexes with Diamine Ligands as Potential Anticancer Agents.

Background: The discovery of cisplatin and the subsequent research revealed the importance of dinitrogen-containing moiety for the anticancer action of metal complexes. Moreover, certain diamine ligands alone display cytotoxicity that contributes to the overall activity of corresponding complexes.

Objective: To summarize the current knowledge on the anticancer efficacy, selectivity, and the mechanisms of action of metal complexes with various types of diamine ligands.

Higher concentration of interleukin 6 - A possible link between major depressive disorder and childhood abuse.

Little is known about the correlation between IL-6 and childhood abuse and neglect which may be risk factors for the development of affective disorders in adulthood. The aim of this study was to analyze differences in serum concentrations of IL-6 between patients with major depressive disorder and healthy controls, and to investigate possible correlations with adverse childhood experiences. Peripheral venous blood samples were obtained from 64 patients who fulfilled DSM-IV-R criteria for a current major depressive episode without psychotic symptoms (MDD) and 53 healthy controls, matched for age and gender.

In vitro and in vivo antimelanoma effect of ethyl ester cyclohexyl analog of ethylenediamine dipropanoic acid.

Melanoma, an aggressive skin tumor with high metastatic potential, is associated with high mortality and increasing morbidity. Multiple available chemotherapeutic and immunotherapeutic modalities failed to improve survival in advanced disease, and the search for new agents is ongoing. The aim of this study was to investigate antimelanoma effects of O,O-diethyl-(S,S)-ethylenediamine-N,N'di-2-(3-cyclohexyl) propanoate dihydrochloride (EE), a previously synthesized and characterized organic compound.

Antileukemic action of novel diamine Pt(II) halogenido complexes: Comparison of the representative novel Pt(II) with corresponding Pt(IV) complex.

This study presents the synthesis, characterization, and antitumor action of five new Pt(II) halogenido, chlorido, and iodido complexes with edda type of ligands. (S,S)-Ethylenediamine-N,N'-di-2-(3-cyclohexyl)propanoic acid dihydrochloride and its methyl, ethyl, and n-propyl esters were prepared according to the previously reported procedure. All investigated complexes were characterized by IR, ESI-MS ( H, C, and HMBC) NMR spectroscopy, and elemental analysis.

Autophagy suppression sensitizes glioma cells to IMP dehydrogenase inhibition-induced apoptotic death.

We investigated the role of autophagy, a process of controlled self-digestion, in the in vitro anticancer action of the inosine monophosphate dehydrogenase (IMPDH) inhibitor ribavirin. Ribavirin-triggered oxidative stress, caspase activation, and apoptotic death in U251 human glioma cells were associated with the induction of autophagy, as confirmed by intracellular acidification, appearance of autophagic vesicles, conversion of microtubule associated protein 1 light chain 3 (LC3)-I to autophagosome-associated LC3-II, and degradation of autophagic target p62/sequestosome 1. Ribavirin downregulated the activity of autophagy-inhibiting mammalian target of rapamycin complex 1 (mTORC1), as indicated by a decrease in phosphorylation of the mTORC1 substrate ribosomal p70S6 kinase and reduction of the mTORC1-activating Src/Akt signaling.

Glucocerebrosidase and parkinsonism: lessons to learn.

Both homo- (causing autosomal-recessive Gaucher's disease; GD) and heterozygous mutations in the glucocerebrosidase gene (GBA) are associated with Parkinson's disease (PD), and represent the most robust known genetic susceptibility factors identified in PD. Since the accumulation of α-synuclein has been considered critical to the pathogenesis of PD among several possible pathways through which glucocerebrosidase (GCase) deficiency may promote the pathogenesis of PD, particular attention was given to the reciprocity with α-synuclein levels, lysosomal dysfunction, endoplasmatic reticulum-Golgi trafficking of GCase, dysregulation of calcium homeostasis and mitochondrial abnormalities. The proportion of PD patients that carry GBA mutations is estimated to be approximately between 5 and 10 %.

Mitochondrial impairment, apoptosis and autophagy in a rat brain as immediate and long-term effects of perinatal phencyclidine treatment - influence of restraint stress.

Phencyclidine (PCP) acts as a non-competitive antagonist of glutamatergic N-methyl-d-aspartate receptor. Its perinatal administration to rats causes pathophysiological changes that mimick some pathological features of schizophrenia (SCH). Numerous data indicate that abnormalities in mitochondrial structure and function could be associated with the development of SCH.

Statin-mediated inhibition of cholesterol synthesis induces cytoprotective autophagy in human leukemic cells.

Statins exhibit anti-leukemic properties due to suppression of the mevalonate pathway by the inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase, and subsequent depletion of cholesterol, farnesylpyrophosphate, and geranylgeranylpyrophosphate. We investigated the role of autophagy, a controlled intracellular self-digestion, in the anti-leukemic action of statins. Treatment with low concentrations (≤6 µM) of statins, cholesterol depletion, and specific inhibition of cholesterol synthesis and protein farnesylation or geranylgeranylation, all inhibited proliferation of leukemic cell lines and primary leukemic cells without inducing overt cell death.

Men with lower HDL cholesterol levels have significant increment of soluble CD40 ligand and high-sensitivity CRP levels following the cessation of long-term clopidogrel therapy.

Aim: The aim of this study was to examine whether the termination of long-term clopidogrel therapy results in a proinflammatory state and whether lipid parameters influence the inflammatory response after stopping the drug.

Methods: A prospective, multicenter study was conducted among 200 patients with implanted coronary stents who received dual antiplatelet therapy for one year, without ischemic or bleeding events. According to the guidelines, clopidogrel was discontinued after one year.

Synthesis, characterization and ROS-mediated cytotoxic action of novel (S,S)-1,3-propanediamine-N,N'-di-2-(3-cyclohexyl)propanoic acid and corresponding esters.

This study involves the synthesis and characterization of novel cyclohexyl 1,3-propanediamine-N,N'-diacetate molecules as well as investigation of their cytotoxic action. New acid 1a was synthesized by reaction between (S)-2-amino-3-cyclohexylpropanoic acid and 1,3-dibromopropane, while the esters (1b-1e) derived from this acid were obtained by reaction of the corresponding absolute alcohol, thionyl chloride and synthesized acid. All compounds were characterized by IR, ESI-MS, ((1)H, (13)C and HSQC) NMR spectroscopy and elemental analysis.

High Risk First Degree Relatives of Type 1 Diabetics: An Association with Increases in CXCR3(+) T Memory Cells Reflecting an Enhanced Activity of Th1 Autoimmune Response.

We analyzed the level of (a) CXCR3(+) (Th1) and CCR4(+) (Th2) T memory cells (b) interferon- γ inducible chemokine (IP-10)(Th1) and thymus and activation-regulated chemokine (TARC)(Th2), in 51 first degree relatives (FDRs) of type 1 diabetics (T1D) (17 high risk FDRs (GADA(+), IA-2(+)) and 34 low risk FDRs (GADA(-), IA-2(-))), 24 recent-onset T1D (R-T1D), and 18 healthy subjects. T memory subsets were analyzed by using four-color immunofluorescence staining and flowcytometry. IP-10 and TARC were determined by ELISA.

Inhibition of mTOR-dependent autophagy sensitizes leukemic cells to cytarabine-induced apoptotic death.

The present study investigated the role of autophagy, a cellular self-digestion process, in the cytotoxicity of antileukemic drug cytarabine towards human leukemic cell lines (REH, HL-60, MOLT-4) and peripheral blood mononuclear cells from leukemic patients. The induction of autophagy was confirmed by acridine orange staining of intracellular acidic vesicles, electron microscopy visualization of autophagic vacuoles, as well as by the increase in autophagic proteolysis and autophagic flux, demonstrated by immunoblot analysis of p62 downregulation and LC3-I conversion to autophagosome-associated LC3-II in the presence of proteolysis inhibitors, respectively. Moreover, the expression of autophagy-related genes Atg4, Atg5 and Atg7 was stimulated by cytarabine in REH cells.

Palladium(II) complexes with N-heteroaromatic bidentate hydrazone ligands: the effect of the chelate ring size and lipophilicity on in vitro cytotoxic activity.

Novel Pd(II) complex with N-heteroaromatic Schiff base ligand, derived from 8-quinolinecarboxaldehyde (q8a) and ethyl hydrazinoacetate (haOEt), was synthesized and characterized by analytical and spectroscopy methods. The structure of novel complex, as well as structures of its quinoline and pyridine analogues, was optimized by density functional theory calculations, and theoretical data show good agreement with experimental results. A cytotoxic action of the complexes was evaluated on cultures of human promyelocytic leukemia (HL-60), human glioma (U251), rat glioma (C6), and mouse fibrosarcoma (L929) cell lines.

A comparative study of in vitro cytotoxic, antioxidant, and antimicrobial activity of Pt(II), Zn(II), Cu(II), and Co(III) complexes with N-heteroaromatic Schiff base (E)-2-[N'-(1-pyridin-2-yl-ethylidene)hydrazino]acetate.

In search for novel biologically active metal based compounds, an evaluation of in vitro cytotoxic, antioxidant, and antimicrobial activity of new Pt(II) complex and its Zn(II), Cu(II), and Co(III) analogues, with NNO tridentately coordinated N-heteroaromatic Schiff base ligand (E)-2-[N'-(1-pyridin-2-yl-ethylidene)hydrazino]acetate, was performed. Investigation of antioxidative properties showed that all of the compounds have strong radical scavenging potencies. The Zn(II) complex showed potent inhibition of DNA cleavage by hydroxyl radical.

The protective role of AMP-activated protein kinase in alpha-synuclein neurotoxicity in vitro.

In the present study, we investigated the role of the main intracellular energy sensor, AMP-activated protein kinase (AMPK), in the in vitro neurotoxicity of α-synuclein (ASYN), one of the key culprits in the pathogenesis of Parkinson's disease. The loss of viability in retinoic acid-differentiated SH-SY5Y human neuroblastoma cells inducibly overexpressing wild-type ASYN was associated with the reduced activation of AMPK and its activator LKB1, as well as AMPK target Raptor. ASYN-overexpressing rat primary neurons also displayed lower activity of LKB1/AMPK/Raptor pathway.

The mechanisms of in vitro cytotoxicity of mountain tea, Sideritis scardica, against the C6 glioma cell line.

Sideritis scardica (mountain tea) is an endemic plant on the Balkan Peninsula traditionally used for treating different conditions, mainly of inflammatory nature. This study was aimed to examine the cytotoxic activity of different S. scardica extracts against the rat glioma C6 line and rat astrocytes in primary culture.

Jatrophane diterpenoids from the latex of Euphorbia dendroides and their anti-P-glycoprotein activity in human multi-drug resistant cancer cell lines.

Thirteen jatrophane diterpenoids (1-10, 13-15), three previously isolated (11, 12, 16) and a known tigliane (17) were isolated from the latex of Euphorbia dendroides. The structures and relative configurations of compounds were elucidated by spectroscopic techniques. The P-glycoprotein (P-gp) inhibiting activities of the representative set of jatrophanes (1-6 and 11-16) have been assessed.

Cyclohexyl analogues of ethylenediamine dipropanoic acid induce caspase-independent mitochondrial apoptosis in human leukemic cells.

We investigated the cytotoxicity of recently synthesized (S,S)-ethylendiamine-N,N'-di-2-(3-cyclohexyl)propanoic acid esters toward human leukemic cell lines and healthy blood mononuclear cells. Cell viability was assessed by acid phosphatase assay, apoptosis, and differentiation were analyzed by flow cytometry and electron microscopy, while intracellular localization of apoptosis-inducing factor (AIF) was determined by immunoblotting. It was demonstrated that methyl, ethyl, and n-propyl esters were toxic to HL-60, REH, MOLT-4, KG-1, JVM-2, and K-562 leukemic cell lines, while the nonesterified parental compound and n-butyl ester were devoid of cytotoxic action.