INTRODUCTION: Transmission of malaria requires an obligatory biological interplay between female ... more INTRODUCTION: Transmission of malaria requires an obligatory biological interplay between female Anopheles mosquitoes and a parasite of the genus Plasmodium, the etiological agent of the disease (1). P. falciparum Calcium Dependent Protein Kinase 4 (PfCDPK4) is recognized as a molecular switch that translates the XA-induced calcium signal into a cellular response by regulating cell cycle progression (2). CDPKs family is characterized by the presence of a kinase domain, an autoinhibitory junction domain (J) and a C-terminal regulatory domain that is able to activate the enzyme following calcium binding (3).
ErbB2 and EGF receptors are two members of the ErbB receptor superfamily of tyrosinekinases. Amon... more ErbB2 and EGF receptors are two members of the ErbB receptor superfamily of tyrosinekinases. Among the different tissues, they are of particular importance in the mammary gland during growth, differentiation, and suckling. Moreover the overexpression of ErbB2 and
Summary The Atomic Force Microscope (AFM) is able to image the surface prope1ties of ali types of... more Summary The Atomic Force Microscope (AFM) is able to image the surface prope1ties of ali types of mate ri a ls (conductors, in sul ators, bio logical and vegetai samples) with a very hi gh resolution and in the native state. ln parti cul ar, AFM is used to study a number of biologie system such as DNA-replication and pro tein/ prote in , DNA/protein interactions; furthermore, in cosmetology, it's suitabl e to study the fun damental characteri sti cs of the skin , like elasticity and wrinkledness, a nd to compare for exampl e morphological properti es of human virgin hair and c he mical or polymer treated hair. The most important characteri stics of thi s instrume nt in cosmetological analyses are: • the samples can be directe ly examined without previus treatment, i.e. in native conditions, • data are col lect in a di gitai form, • 3-D image rendering with vari able magnification and s hading, • view of the recorded image from a ny point of the space. Jn our laboratory we an...
Breast cancer is the second leading cause of cancer-related death in women in the world, and its ... more Breast cancer is the second leading cause of cancer-related death in women in the world, and its management includes a combination of surgery, radiation therapy, chemotherapy, and immunotherapy, whose effectiveness depends largely, but not exclusively, on the molecular subtype (Luminal A, Luminal B, HER2+ and Triple Negative). All breast cancer subtypes are accompanied by peculiar and substantial changes in sphingolipid metabolism. Alterations in sphingolipid metabolite levels, such as ceramides, dihydroceramide, sphingosine, sphingosine-1-phosphate, and sphingomyelin, as well as in their biosynthetic and catabolic enzymatic pathways, have emerged as molecular mechanisms by which breast cancer cells grow, respond to or escape therapeutic interventions and could take on diagnostic and prognostic value. In this review, we summarize the current landscape around two main themes: 1. sphingolipid metabolites, enzymes and transport proteins that have been found dysregulated in human breast...
Additional file 1. Measurement of nitrite and nitrate concentrations in BMDM treated with malaria... more Additional file 1. Measurement of nitrite and nitrate concentrations in BMDM treated with malarial hemozoin.
INTRODUCTION: Leishmania tropica is the etiological agent of cutaneous leishmaniasis. Pattern rec... more INTRODUCTION: Leishmania tropica is the etiological agent of cutaneous leishmaniasis. Pattern recognition receptors such as toll-like receptors or nucleotide oligomerization domain-like receptors (NLR) have been associated with the disease. The role in innate immune responses against L. tropica of NOD2, a member of the NLR family, was investigated. MATERIALS AND METHODS: Interferon gamma (IFN-\u3b3)-primed or unprimed immortalized mouse bone marrow macrophages (BMDM)-wild type (WT) or -NOD2 -/- were infected with L. tropica at different parasite/macrophage ratios (i.e. 2.5, 5, or 10:1), for 24h. Controls, such as medium alone, muramyldipeptide (MDP), or lipopolysaccharide (LPS), were included. Levels of cytokines or nitrite released into supernatants were measured through ELISA or Griess reagents. Levels of inducible nitric oxide synthase (iNOS) mRNA and protein were retrieved through Real-Time PCR and Western blot analyses, respectively. Also, unprimed BMDM- RIP2 -/- or -CARD9 -/- , two downstream components of NOD2 activation, were stimulated with the same ratios of L. tropica or controls, and the production of the pro-inflammatory cytokine TNF-a was compared with BMDM-WT. RESULTS AND CONCLUSIONS: Data showed that L. tropica did not induce the production of nitric oxide in unprimed BMDM-WT. L. tropica induced higher levels of nitric oxide in IFN-\u3b3- primed BMDM-WT than in unstimulated cells. Stimulation due to L. tropica, or the control MDP (known to activate NOD2), was abrogated in the BMDM-NOD2 -/- , but not LPS, as so the expression levels of inducible nitric oxide synthase (iNOS) mRNA or protein. In addition, NOD2, RIP2 or CARD9 showed to be involved in the induction of TNF-a release from BMDM. These data suggest an involvement of NOD2 pathway in innate immune response to L. tropica infection
Summary In the epid ermis of terrestrial vertebrates stratum corneum lipids are known to pl ay an... more Summary In the epid ermis of terrestrial vertebrates stratum corneum lipids are known to pl ay an important ro le as regulators of skin permeabi lity; particu larly ceramides, some of whi c h with very long chain, hydroxy fatty acids, are important components of this "barri er" function. Ceramides are derived from the hydrolys is of previous existing glucosylceramide during the terminal stages of epidermal differentiation, due to the presence of a li sosomal-like glu cosylceramid ase locali sed in the lamellar bodies in the space between stratum granulosum and the inferior layer of stratum corneum: the defi ciency of glu cosylceramidase, local ized in lysosome, is responsible of Gaucher's disease. In thi s study we investigateci the glycolipi ds and ceramide di stribution in th e epiderm is of 4 Gau cher's patients (two of type I and two of type 3), compaired wi th th e same parameters in 4 healthy donors. The comparison between the pathological sampl es and the...
The Italian Space Agency, within the frame of the mission "Beyond" has promoted the "YiSS-Youth I... more The Italian Space Agency, within the frame of the mission "Beyond" has promoted the "YiSS-Youth ISS Science" competition, to involve secondary school students in the process of conception and execution of a space experiment. The XENOG-RISS experiment was selected by the Italian Space Agency to fly onboard the ISS. The project foresees an active involvement of students into a multidisciplinary activity aimed at studying the effect of microgravity on growth and regeneration processes, using an animal model (Xenopus laevis) that allows both processes to be observed simultaneously. The project involves the preparation of a Xenopus laevis tadpole culture within a Xenopus Experiment Unit (XEU). The XEU has been integrated into a powered metallic sealed container called Biokon. The activation on the ISS ensured the feeding of the tadpoles, the recirculation of water and the acquisition of images. The control electronics, including the acquisition system, was designed and realized by the students under teacher supervision in collaboration with engineers from Kayser Italia. The integration process of the experiment onboard the ISS was provided by the UTISS Team (Argotec/Telespazio) that supported safety evaluation, requirements verification, payload manifesting, delivery, operations and recovery. The facility has been launched with Space-X CRS-19 and recovered after 30 days. The information derived from this experiment will help to understand the mechanisms underlying the effect of microgravity upon the processes of growth, repair and regeneration of tissues. A better knowledge of these processes is important in defining protocols for the management of traumatic injuries, wounds and chronic ulcers both in Space and on Earth.
Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids, 2010
Gangliosides are well-known regulators of cell differentiation through specific interactions with... more Gangliosides are well-known regulators of cell differentiation through specific interactions with growth factor receptors. Previously, our group provided the first evidence about stable association of ganglioside GM 3 to EGFR/ErbB2 heterodimers in mammary epithelial cells. Goals of the present study were to better define the role of gangliosides in EGFR/ErbB2 heterodimerization and receptor phosphorylation events and to analyze their involvement in mammary cell differentiation. Experiments have been conducted using the ceramide analogue (+/−)-treo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol hydrochloride ([D]-PDMP), which inhibits ceramide glucosyltransferase resulting in the endogenous ganglioside depletion, and the lactogenic hormone mix DIP (dexamethasone, insulin, prolactin), which induces cell differentiation and β-casein mRNA synthesis. In addition, treatments of ganglioside-depleted cells with exogenous GM 3 have been carried out to ascertain the specific involvement of this ganglioside. Results from co-immunoprecipitation and Western blot experiments have shown that the endogenous ganglioside depletion resulted in the disappearance of SDS-stable EGFR/ErbB2 heterodimers and in the appearance of tyrosine-phosphorylated EGFR also in the absence of EGF stimulation; exogenous GM 3 added in combination with [D]-PDMP reversed both these effects. In contrast, the tyrosine phosphorylation of ErbB2 in ganglioside-depleted cells occurred only after EGF stimulation. Moreover, when ganglioside-depleted cells were treated with DIP in absence of EGF, β-casein gene expression appeared strongly down-regulated, and β-casein mRNA levels were partially restored by exogenous GM 3 treatment. Altogether, although the involvement of other ganglioside species cannot be excluded, these findings sustain the ganglioside GM 3 as an essential molecule for EGFR/ErbB2 heterodimer stability and important regulator of EGFR tyrosine phosphorylation, but it is not crucial for tyrosine phosphorylation of the heterodimerization partner ErbB2. Moreover, modulation of EGFR phosphorylation may explain how gangliosides contribute to regulate the lactogenic hormone-induced mammary cell differentiation.
INTRODUCTION: Transmission of malaria requires an obligatory biological interplay between female ... more INTRODUCTION: Transmission of malaria requires an obligatory biological interplay between female Anopheles mosquitoes and a parasite of the genus Plasmodium, the etiological agent of the disease (1). P. falciparum Calcium Dependent Protein Kinase 4 (PfCDPK4) is recognized as a molecular switch that translates the XA-induced calcium signal into a cellular response by regulating cell cycle progression (2). CDPKs family is characterized by the presence of a kinase domain, an autoinhibitory junction domain (J) and a C-terminal regulatory domain that is able to activate the enzyme following calcium binding (3).
ErbB2 and EGF receptors are two members of the ErbB receptor superfamily of tyrosinekinases. Amon... more ErbB2 and EGF receptors are two members of the ErbB receptor superfamily of tyrosinekinases. Among the different tissues, they are of particular importance in the mammary gland during growth, differentiation, and suckling. Moreover the overexpression of ErbB2 and
Summary The Atomic Force Microscope (AFM) is able to image the surface prope1ties of ali types of... more Summary The Atomic Force Microscope (AFM) is able to image the surface prope1ties of ali types of mate ri a ls (conductors, in sul ators, bio logical and vegetai samples) with a very hi gh resolution and in the native state. ln parti cul ar, AFM is used to study a number of biologie system such as DNA-replication and pro tein/ prote in , DNA/protein interactions; furthermore, in cosmetology, it's suitabl e to study the fun damental characteri sti cs of the skin , like elasticity and wrinkledness, a nd to compare for exampl e morphological properti es of human virgin hair and c he mical or polymer treated hair. The most important characteri stics of thi s instrume nt in cosmetological analyses are: • the samples can be directe ly examined without previus treatment, i.e. in native conditions, • data are col lect in a di gitai form, • 3-D image rendering with vari able magnification and s hading, • view of the recorded image from a ny point of the space. Jn our laboratory we an...
Breast cancer is the second leading cause of cancer-related death in women in the world, and its ... more Breast cancer is the second leading cause of cancer-related death in women in the world, and its management includes a combination of surgery, radiation therapy, chemotherapy, and immunotherapy, whose effectiveness depends largely, but not exclusively, on the molecular subtype (Luminal A, Luminal B, HER2+ and Triple Negative). All breast cancer subtypes are accompanied by peculiar and substantial changes in sphingolipid metabolism. Alterations in sphingolipid metabolite levels, such as ceramides, dihydroceramide, sphingosine, sphingosine-1-phosphate, and sphingomyelin, as well as in their biosynthetic and catabolic enzymatic pathways, have emerged as molecular mechanisms by which breast cancer cells grow, respond to or escape therapeutic interventions and could take on diagnostic and prognostic value. In this review, we summarize the current landscape around two main themes: 1. sphingolipid metabolites, enzymes and transport proteins that have been found dysregulated in human breast...
Additional file 1. Measurement of nitrite and nitrate concentrations in BMDM treated with malaria... more Additional file 1. Measurement of nitrite and nitrate concentrations in BMDM treated with malarial hemozoin.
INTRODUCTION: Leishmania tropica is the etiological agent of cutaneous leishmaniasis. Pattern rec... more INTRODUCTION: Leishmania tropica is the etiological agent of cutaneous leishmaniasis. Pattern recognition receptors such as toll-like receptors or nucleotide oligomerization domain-like receptors (NLR) have been associated with the disease. The role in innate immune responses against L. tropica of NOD2, a member of the NLR family, was investigated. MATERIALS AND METHODS: Interferon gamma (IFN-\u3b3)-primed or unprimed immortalized mouse bone marrow macrophages (BMDM)-wild type (WT) or -NOD2 -/- were infected with L. tropica at different parasite/macrophage ratios (i.e. 2.5, 5, or 10:1), for 24h. Controls, such as medium alone, muramyldipeptide (MDP), or lipopolysaccharide (LPS), were included. Levels of cytokines or nitrite released into supernatants were measured through ELISA or Griess reagents. Levels of inducible nitric oxide synthase (iNOS) mRNA and protein were retrieved through Real-Time PCR and Western blot analyses, respectively. Also, unprimed BMDM- RIP2 -/- or -CARD9 -/- , two downstream components of NOD2 activation, were stimulated with the same ratios of L. tropica or controls, and the production of the pro-inflammatory cytokine TNF-a was compared with BMDM-WT. RESULTS AND CONCLUSIONS: Data showed that L. tropica did not induce the production of nitric oxide in unprimed BMDM-WT. L. tropica induced higher levels of nitric oxide in IFN-\u3b3- primed BMDM-WT than in unstimulated cells. Stimulation due to L. tropica, or the control MDP (known to activate NOD2), was abrogated in the BMDM-NOD2 -/- , but not LPS, as so the expression levels of inducible nitric oxide synthase (iNOS) mRNA or protein. In addition, NOD2, RIP2 or CARD9 showed to be involved in the induction of TNF-a release from BMDM. These data suggest an involvement of NOD2 pathway in innate immune response to L. tropica infection
Summary In the epid ermis of terrestrial vertebrates stratum corneum lipids are known to pl ay an... more Summary In the epid ermis of terrestrial vertebrates stratum corneum lipids are known to pl ay an important ro le as regulators of skin permeabi lity; particu larly ceramides, some of whi c h with very long chain, hydroxy fatty acids, are important components of this "barri er" function. Ceramides are derived from the hydrolys is of previous existing glucosylceramide during the terminal stages of epidermal differentiation, due to the presence of a li sosomal-like glu cosylceramid ase locali sed in the lamellar bodies in the space between stratum granulosum and the inferior layer of stratum corneum: the defi ciency of glu cosylceramidase, local ized in lysosome, is responsible of Gaucher's disease. In thi s study we investigateci the glycolipi ds and ceramide di stribution in th e epiderm is of 4 Gau cher's patients (two of type I and two of type 3), compaired wi th th e same parameters in 4 healthy donors. The comparison between the pathological sampl es and the...
The Italian Space Agency, within the frame of the mission "Beyond" has promoted the "YiSS-Youth I... more The Italian Space Agency, within the frame of the mission "Beyond" has promoted the "YiSS-Youth ISS Science" competition, to involve secondary school students in the process of conception and execution of a space experiment. The XENOG-RISS experiment was selected by the Italian Space Agency to fly onboard the ISS. The project foresees an active involvement of students into a multidisciplinary activity aimed at studying the effect of microgravity on growth and regeneration processes, using an animal model (Xenopus laevis) that allows both processes to be observed simultaneously. The project involves the preparation of a Xenopus laevis tadpole culture within a Xenopus Experiment Unit (XEU). The XEU has been integrated into a powered metallic sealed container called Biokon. The activation on the ISS ensured the feeding of the tadpoles, the recirculation of water and the acquisition of images. The control electronics, including the acquisition system, was designed and realized by the students under teacher supervision in collaboration with engineers from Kayser Italia. The integration process of the experiment onboard the ISS was provided by the UTISS Team (Argotec/Telespazio) that supported safety evaluation, requirements verification, payload manifesting, delivery, operations and recovery. The facility has been launched with Space-X CRS-19 and recovered after 30 days. The information derived from this experiment will help to understand the mechanisms underlying the effect of microgravity upon the processes of growth, repair and regeneration of tissues. A better knowledge of these processes is important in defining protocols for the management of traumatic injuries, wounds and chronic ulcers both in Space and on Earth.
Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids, 2010
Gangliosides are well-known regulators of cell differentiation through specific interactions with... more Gangliosides are well-known regulators of cell differentiation through specific interactions with growth factor receptors. Previously, our group provided the first evidence about stable association of ganglioside GM 3 to EGFR/ErbB2 heterodimers in mammary epithelial cells. Goals of the present study were to better define the role of gangliosides in EGFR/ErbB2 heterodimerization and receptor phosphorylation events and to analyze their involvement in mammary cell differentiation. Experiments have been conducted using the ceramide analogue (+/−)-treo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol hydrochloride ([D]-PDMP), which inhibits ceramide glucosyltransferase resulting in the endogenous ganglioside depletion, and the lactogenic hormone mix DIP (dexamethasone, insulin, prolactin), which induces cell differentiation and β-casein mRNA synthesis. In addition, treatments of ganglioside-depleted cells with exogenous GM 3 have been carried out to ascertain the specific involvement of this ganglioside. Results from co-immunoprecipitation and Western blot experiments have shown that the endogenous ganglioside depletion resulted in the disappearance of SDS-stable EGFR/ErbB2 heterodimers and in the appearance of tyrosine-phosphorylated EGFR also in the absence of EGF stimulation; exogenous GM 3 added in combination with [D]-PDMP reversed both these effects. In contrast, the tyrosine phosphorylation of ErbB2 in ganglioside-depleted cells occurred only after EGF stimulation. Moreover, when ganglioside-depleted cells were treated with DIP in absence of EGF, β-casein gene expression appeared strongly down-regulated, and β-casein mRNA levels were partially restored by exogenous GM 3 treatment. Altogether, although the involvement of other ganglioside species cannot be excluded, these findings sustain the ganglioside GM 3 as an essential molecule for EGFR/ErbB2 heterodimer stability and important regulator of EGFR tyrosine phosphorylation, but it is not crucial for tyrosine phosphorylation of the heterodimerization partner ErbB2. Moreover, modulation of EGFR phosphorylation may explain how gangliosides contribute to regulate the lactogenic hormone-induced mammary cell differentiation.
Uploads
Papers by Stefania Zava