Mariarita Perri

Combined Low Doses of PPARγ and RXR Ligands Trigger an Intrinsic Apoptotic Pathway in Human Breast Cancer Cells

Ligand activation of peroxisome proliferator-activated receptor (PPAR)gamma and retinoid X receptor (RXR) induces antitumor effects in cancer. We evaluated the ability of combined treatment with nanomolar levels of the PPARgamma ligand rosiglitazone (BRL) and the RXR ligand 9-cis-retinoic acid (9RA) to promote antiproliferative effects in breast cancer cells. BRL and 9RA in combination strongly inhibit of cell viability in MCF-7, MCF-7TR1, SKBR-3, and T-47D breast cancer cells, whereas MCF-10 normal breast epithelial cells are unaffected. In MCF-7 cells, combined treatment with BRL and 9RA up-regulated mRNA and protein levels of both the tumor suppressor p53 and its effector p21(WAF1/Cip1). Functional experiments indicate that the nuclear factor-kappaB site in the p53 promoter is required for the transcriptional response to BRL plus 9RA. We observed that the intrinsic apoptotic pathway in MCF-7 cells displays an ordinated sequence of events, including disruption of mitochondrial membrane potential, release of cytochrome c, strong caspase 9 activation, and, finally, DNA fragmentation. An expression vector for p53 antisense abrogated the biological effect of both ligands, which implicates involvement of p53 in PPARgamma/RXR-dependent activity in all of the human breast malignant cell lines tested. Taken together, our results suggest that multidrug regimens including a combination of PPARgamma and RXR ligands may provide a therapeutic advantage in breast cancer treatment.

Influence of all-trans-retinoic acid on oxoglutarate carrier via retinoylation reaction.

All-trans-retinoic acid (atRA), an activated metabolite of vitamin A, is incorporated covalently into proteins both invivo and invitro. AtRA reduced the transport activity of the oxoglutarate carrier (OGC) isolated from testes mitochondria to 58% of control via retinoylation reaction. Labeling of testes mitochondrial proteins with (3)HatRA demonstrated the binding of atRA to a 31.5 KDa protein. This protein was identified as OGC due to the competition for the labeling reaction with 2-oxoglutarate, the specific OGC substrate. The role of retinoylated proteins is currently being explored and here we have the first evidence that retinoic acids bind directly to OGC and inhibit its activity in rat testes mitochondria via retinoylation reaction. This study indicates the evidence of a specific interaction between atRA and OGC and establishes a novel mechanism for atRA action, which could influence the physiological biosynthesis of testosterone in situations such as retinoic acid treatment.

Theophylline action on primary human bronchial epithelial cells under proinflammatory stimuli and steroidal drugs: a therapeutic rationale approach

Theophylline is a natural compound present in tea. Because of its property to relax smooth muscle it is used in pharmacology for the treatment of airway diseases (ie, chronic obstructive pulmonary disease, asthma). However, this effect on smooth muscle is dose dependent and it is related to the development of side effects. Recently, an increasing body of evidence suggests that theophylline, at low concentrations, also has anti-inflammatory effects related to the activation of histone deacetylases. In this study, we evaluated the effects of theophylline alone and in combination with corticosteroids on human bronchial epithelial cells under inflammatory stimuli. Theophylline administrated alone was not able to reduce growth-stimulating signaling via extracellular signal-regulated kinases activation and matrix metalloproteases release, whereas it strongly counteracts this biochemical behavior when administered in the presence of corticosteroids. These data provide scientific evidence for supporting the rationale for the pharmacological use of theophylline and corticosteroid combined drug.

Human kidney podocyte cell population as a novel biological target of nerve growth factor.

Abstract Human podocytes are highly specialized cells with a key role in kidney physiology. Alteration of their structure as a consequence of injury or developmental failure leads to severe renal diseases. Although several studies have tried to elucidate the molecular framework of this cellular system, the functional bases for the maintenance of podocytes in their specialized state to sustain kidney barrier filtration are not completely understood. In this study, the capability of podocytes to produce and secrete the nerve growth factor (NGF) has been demonstrated via a validated in vitro model. During the process of cell differentiation, NGF and its receptors are modulated in human podocytes just as NGF-responsive neurons. Blockade of NGF biological activity results in severe changes of cell morphology. Collectively, our results outline a novel function of the neurotrophin and add a new cellular target in the complex biological framework of NGF.

9-cis Retinoic acid modulates myotrophin expression and its miR in physiological and pathophysiological cell models

ABSTRACT Functional studies indicate that essential cellular processes are controlled by Vitamin A derivatives. Among these the retinoic acid isoforms, all‐trans‐ and 9‐cis (9cRA), regulate the expression of various genes in both physiological and pathological conditions. Using several in vitro experimental models such as pancreatic &bgr;‐cells, pre‐adipocytes and breast cancer cells with different phenotypes, we demonstrated the capability of 9cRA to modulate myotrophin (Mtpn) and miR‐375 expressions. The 9cRA effect in pancreatic &bgr;‐cells line INS‐1 832/13 point out a decreased expression of Mptn at both mRNA and protein levels associated to a concomitant increase of miR‐375. We also studied the effect of this molecule on 3T3‐L1 pre‐adipocytes cells demonstrating a down‐regulation of Mtpn and a dramatic increase of miR‐375. Moreover, in the in vitro breast cancer model such as MDA‐MB‐231 and MCF‐7 cells, 9cRA showed different effect on both Mtpn and miR‐375 expression. In INS‐1 832/13, 3T3‐L1 pre‐adipocytes and MCF‐7 but not in MDA‐MB‐231, the effect of 9cRA on Mptn gene expression and its miR was under the control of RARs and RXRs receptors, as revealed by the exposure of these cell line to LE540 or HX603 receptor antagonists. In our findings 9cRA emerges has a hormone with a regulatory action on miR‐375 that in most cases interfere with Mtpn expression.

Novel Gold and Silver Carbene Complexes Exert Antitumor Effects Triggering the Reactive Oxygen Species Dependent Intrinsic Apoptotic Pathway

Cisplatin and other platinum‐based drugs are well‐known valid anticancer drugs. However, during chemotherapy, the presence of numerous side effects and the onset of frequent phenomena of resistance has pushed many research groups to devise new metal‐based compounds holding improved anticancer properties and fewer undesired effects. Amongst the variety of synthesized compounds, significant antiproliferative effects have been obtained by employing organometallic compounds, particularly those based on silver and gold. With this in mind, we synthesized four compounds, two silver complexes and two gold complexes, with good inhibitory effects on the inu2005vitro proliferation of breast and ovarian cancer‐cell models. The antitumor activity of the most active compound, that is, AuL4, was found to be ninefold higher than that of cisplatin, and this compound induced dramatic morphological changes in HeLa cells. AuL4 induced PARP‐1 cleavage, caspasesu20053/7 and 9 activation, mitochondria disruption, cytochromeu2005c release in cancer‐cell cytoplasm, and the intracellular production of reactive oxygen species. Thus, AuL4 treatment caused cancer‐cell death by the intrinsic apoptotic pathway, whereas no cytotoxic effects were recorded upon treating non‐tumor cell lines. The reported outcomes may be an important contribution to the expanding knowledge of medicinal bio‐organometallic chemistry and enlarge the available anticancer toolbox, offering improved features, such as higher activity and/or selectivity, and opening the way to new discoveries and applications.

When Nutraceuticals Reinforce Drugs Side Effects: A Case Report

INTRODUCTIONnNutraceutical is a term applied for a plethora of products ranging from isolated nutrients, herbal products to dietary supplements and recently, the interest for a nutraceutical approach to lipid and metabolic disorders is growing. Patients with metabolic conditions seem to appreciate a therapeutic management that does not involve drug treatment, particularly for the side effects due to statins, a class of drug used for lipid disorders. Statins directly induce skeletal muscle injury and in the elderly patients, under polytherapy treatments, this risk relies to an increase in adverse drug reactions due to drug interactions.nnnCASE DESCRIPTIONnHerein we report a 70-year-old woman under polytherapy who developed rhabdomyolysis after starting the administration of a dietary supplement containing monacolin K. Using the Drug Interaction Probability Scale, we postulated that rhabdomyolysis was possibly related to a drug interaction between sertraline, rosuvastatin and monacolin K. These treatments were discontinued leading to a remission of both clinical symptoms and biochemical parameters.nnnCONCLUSIONnThis case report highlights how pharmacological treatment must be periodically reassessed, since elderly people could take drugs by themselves when they donot need.

Variation in Immune-Related microRNAs Profile in Human Milk Amongst Lactating Women

BACKGROUNDnHuman Milk (HM) is a biological fluid representing the first nutrient for newborns. It directly impacts the development of the infants immune system. In this concern, specific microRNAs (miRNAs) such as hsa-miR-21, hsa-miR-181a, hsa-miR-150 and hsa-miR-223 are known to be involved in the innate and acquired immune response.nnnOBJECTIVEnHerein, these miRNAs were evaluated in frozen and pasteurized samples of human colostrum and HM in order to elucidate the distribution and the expression profile of these biological mediators in both biological fluids.nnnMETHODSnUsing quantitative approach qRT-PCR, we analyzed immune-related microRNAs in both, colostrum and HM.nnnRESULTSnOur study provided evidence of a comparable profile of immune specific miRNAs in colostrum and HM. Although we detected all the four miRNAs tested, we point out the prevalence of hsamiR- 181a and hsa-miR-223 indicative to act on T and granulocytes cell populations as selective targets. Therefore, these biomolecules could affect newborns immune homeostasis at early stages of life. While, variation in immune-related miRNAs was found in HM amongst lactating women, it was not evidenced in colostrum. Of interest, pasteurization procedure did not alter the distribution or the expression profile of the miRNAs tested in both colostrum and HM. Herein, we also proposed a simple method to determine the quantity of these biomolecules in biological fluids.nnnCONCLUSIONnConsidering, this evidence the variation in immune-related miRNAs should be take into account and could be relevant for preterm and hospitalized infants who usually received pasteurized HM from donors.

Biochemical and chemical characterization of Cynara cardunculus L. extract and its potential use as co-adjuvant therapy of chronic myeloid leukemia

ETHNOPHARMACOLOGICAL RELEVANCEnAncient mediterranean diet was characterized by consuming the spontaneous forms of Cynara cardunculus L. (CCL), commonly called artichoke. Cultivated and/or spontaneous forms of CC studies have demonstrated that methanol extract of CCL flower and/or cynaropicrin showed remarkable anti-proliferative activity in vitro models of leukocyte cancer cell.nnnAIM OF THE STUDYnChronic myeloid leukemia (CML) is associated with a reciprocal translocation of the long arms of chromosomes 9 and 22 generating the BCR/ABL fusion gene, translated in the p210BCR/ABL oncoprotein kinase. This chimeric protein is the target of a kinase inhibitor, imatinib, but the development of mutations in the ABL kinase domain resulting in drug resistance and several approaches to overcoming resistance have been study. In this concern, we investigated the effect of CCL extract on human K562 CML and K562 imatinib resistant (IMAR) cell proliferation and on p210BCR/ABL expression.nnnMATERIALS AND METHODSnChemical characterization of the CCL extracts was performed by GC/MS analysis and semipreparative RP-HPLC chromatography. Structural characterization of compounds was assessed by 1H-13C NMR and LC/MS analysis. The effects of CCL extracts on the proliferation of K562 CML human cell line and K562 IMAR were screened by MTT assay. The p210BCR/ABL mRNA and protein expressions were analyzed by qRT-PCR and Western blot techniques respectively.nnnRESULTSnWe demonstrate that CCL extract affect cell viability of both K562 CML human cell line and K562 IMAR. The biocomponents of CCL were chemical characterized and we identify cynaropicrin and its deacyl derivative having the capability to down-regulate the p210BCR/ABL oncoprotein.nnnCONCLUSIONSnOur study suggests that the use of those molecules could represent a novel and promising strategy to potentiate the ability of imatinib or of its analogues to induce cancer growth arrest in CML and to delay or overcome the resistance of CML to chemotherapy.

Spotted fever from Rickettsia typhi in an older woman: a case report from a geographic area where it would not be expected

We describe the case of a 75-year-old woman presenting with spotted fever followed by acute renal failure and septic shock. The infection was caused by Rickettsia typhi, not reported in Calabria district (southern Italy) since World War II. The diagnosis of murine typhus was made 3 days after admission and was based solely on clinical criteria when her worsening condition required a prompt move to the intensive care unit. Therapy with tigecycline was then started immediately and the patient improved dramatically. The diagnosis of murine typhus was confirmed 10 days after admission by immunofluorescence assay. Our case is an example of how the diagnosis of murine typhus is challenging. However, in the case of a disease lacking specific symptoms, clinicians should never forget that, even in geographic areas considered free of flea-borne diseases, the components of the enzootic cycle are present and the diagnosis should never be underestimated.