Oncostatin M and STAT3 Signaling Pathways Support Human Trophoblast Differentiation by Inhibiting Inflammatory Stress in Response to IFNγ and GM-CSF

Interleukin-6 (IL-6) superfamily cytokines play critical roles during human pregnancy by promoting trophoblast differentiation, invasion, and endocrine function, and maintaining embryo immunotolerance and protection. In contrast, the unbalanced activity of pro-inflammatory factors such as interferon gamma (IFNγ) and granulocyte-macrophage colony-stimulating factor (GM-CSF) at the maternal-fetal interface have detrimental effects on trophoblast function and differentiation. This study demonstrates how the IL-6 cytokine family member oncostatin M (OSM) and STAT3 activation regulate trophoblast fusion and endocrine function in response to pro-inflammatory stress induced by IFNγ and GM-CSF. Using human cytotrophoblast-like BeWo (CT/BW) cells, differentiated in villous syncytiotrophoblast (VST/BW) cells, we show that beta-human chorionic gonadotrophin (βhCG) production and cell fusion process are affected in response to IFNγ or GM-CSF. However, those effects are abrogated with OSM by modulating the activation of IFNγ-STAT1 and GM-CSF-STAT5 signaling pathways. OSM stimulation enhances the expression of STAT3, the phosphorylation of STAT3 and SMAD2, and the induction of negative regulators of inflammation (e.g., IL-10 and TGFβ1) and cytokine signaling (e.g., SOCS1 and SOCS3). Using STAT3-deficient VST/BW cells, we show that STAT3 expression is required for OSM to regulate the effects of IFNγ in βhCG and E-cadherin expression. In contrast, OSM retains its modulatory effect on GM-CSF-STAT5 pathway activation even in STAT3-deficient VST/BW cells, suggesting that OSM uses STAT3-dependent and -independent mechanisms to modulate the activation of pro-inflammatory pathways IFNγ-STAT1 and GM-CSF-STAT5. Moreover, STAT3 deficiency in VST/BW cells leads to the production of both a large amount of βhCG and an enhanced expression of activated STAT5 induced by GM-CSF, independently of OSM, suggesting a key role for STAT3 in βhCG production and trophoblast differentiation through STAT5 modulation. In conclusion, our study describes for the first time the critical role played by OSM and STAT3 signaling pathways to preserve and regulate trophoblast biological functions during inflammatory stress.

Investigating a new C2-symmetric testosterone dimer and its dihydrotestosterone analog: Synthesis, antiproliferative activity on prostate cancer cell lines and interaction with CYP3A4

The synthesis of a 17α-linked C2-symmetric testosterone dimer and its dihydrotestosterone analog is reported. The dimers were synthesized using a short five-step reaction sequence with 28% and 38% overall yield for the testosterone and dihydrotestosterone dimer, respectively. The dimerization reaction was achieved by an olefin metathesis reaction with 2nd generation Hoveyda-Grubbs catalyst. The dimers and their corresponding 17α-allyl precursors were tested for the antiproliferative activity on androgen-dependent (LNCaP) and androgen-independent (PC3) prostate cancer cell lines. The effects on cells were compared with that of the antiandrogen cyproterone acetate (CPA). The results showed that the dimers were active on both cell lines, with an increased activity towards androgen-dependent LNCaP cells. However, the testosterone dimer (11) was fivefold more active than the dihydrotestosterone dimer (15), with an IC50 of 11.7 μM vs. 60.9 μM against LNCaP cells, respectively, and more than threefold more active than the reference drug CPA (IC50 of 40.7 μM). Likewise, studies on the interaction of new compounds with drug-metabolizing cytochrome P450 3A4 (CYP3A4) showed that 11 was a fourfold stronger inhibitor than 15 (IC50 of 3 μM and 12 μM, respectively). This suggests that changes in the chemical structure of sterol moieties and the manner of their linkage could largely affect both the antiproliferative activity of androgen dimers and their crossreactivity with CYP3A4.

Abstract 3091: Relevance of iNOS expression in bladder cancer stem cells

Background: Bladder cancer (BC) is one of the most common tumors of the male urogenital tract and an important worldwide cause of death. Increasing evidence has indicated the presence of cancer stem cells (CSCs) in many types of tumors, associated with aggressiveness, chemoresistance and relapse. The expression of inducible nitric oxide (NO) synthase (iNOS) in human BC is a poor prognostic factor associated with increased invasion and tumor recurrence. Although there is evidence supporting the role of NO/iNOS in the promotion and progression of BC, the possibility that there are CSCs dependent on endogenous NO generation was not yet been clearly defined. In this study we evaluate the role of NO in CSC maintenance, modulating its production, using pharmacological inhibitors or silencing iNOS expression in a murine BC model. Also, we analyzed the correlation between iNOS expression and stemness-related genes (SG) in human BC samples with different invasion grades.

Methods: iNOS pharmacological inhibitors (pan-NOS or iNOS specific) or shRNA were used on murine BC model with different iNOS expression and invasiveness grade: MB49 [iNOS+, non-muscle invasive (NMI)] and MB49-I [iNOS++, muscle invasive (MI)], in order to analyze cell proliferation, number of CSC determined as spheres forming efficiency (SFE) and SG (Sox 2, Oct4 and Nanog expression) by qPCR. iNOS expression and SG were also analyzed in human BC samples (16 NMI low grade (LG), 10 NMI high grade (HG) and 17 MI).

Results: The number of CSCs was higher in MB49-I than NMI MB49 line (p<0.05), in concordance with the higher expression of iNOS and Sox2, Oct4 and Nanog (p<0.001). iNOS inhibition diminished CSC in both cell lines (p<0.05 vs MB49; p<0.001 vs MB49-I). Inhibition of SG was only observed in MB49-I line (p<0.05). Moreover, the reduction of CSC and SG were more evident in MB49-I-shiNOS (p<0.0001 vs MB49-I scr; p<0.001 vs MB49-I-scr). The in vivo tumorigenic potential of cells derived from MB49-I spheres were higher than the cells growing in monolayers. MB49-I spheres cells treated with iNOS inhibitors did not developed tumors in vivo. Furthermore, MB49-I shiNOS spheres showed an incipient growth and regressed about 5 weeks post inoculation, in correlation with low iNOS and SG expression. Regarding human samples, iNOS was expressed in 78% of MI, 55% HG and 50% LGNMI (p<0.05 vs NMI). SG expression were significantly higher in MI than in NMI LG. Sox2 was expressed 82% in MI, 25% LG and 40% HG in NMI (p=0.0002). 76% of MI samples were positive for Nanog and Oct4 (p<0.05 vs NMI LG). A positive correlation between iNOS and SG expression was found (sox2: p<0.0001; Oct4: p<0.0001 and Nanog: p<0.05).

Conclusion: Together, this results show that iNOS plays an important role in maintenance of CSC and in vivo BC growth by regulating stemness and self-renewal ability. Thus, iNOS identification and inhibition could be a potential target to eradicate CSC, responsible for tumor recurrences.

Citation Format: Denise Belgorosky, Yanina Langle, Julie Girouard, Jovane Hamelin-Morrissette, Lina Marino, Eduardo I. Agüero, Héctor Malagrino, Carlos Reyes-Moreno, Ana M. Eiján. Relevance of iNOS expression in bladder cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3091.

Innovative C2-symmetric testosterone and androstenedione dimers: Design, synthesis, biological evaluation on prostate cancer cell lines and binding study to recombinant CYP3A4

The synthesis of two isomeric testosterone dimers and an androstenedione dimer is reported. The design takes advantage of an efficient transformation of testosterone leading to the synthesis of the key diene, 7α-(buta-1,3-dienyl)-4-androsten-17β-ol-3-one, through an elimination reaction. It was found that in some instances the same reaction led to partial epimerization of the 17β-hydroxyl group into the 17α-hydroxyl group. The specific orientation of the hydroxyl function was confirmed by NMR spectroscopy. Capitalizing on this unforeseen side reaction, several dimers were assembled using an olefin metathesis reaction with Hoveyda-Grubbs catalyst. This led to the formation of two isomeric testosterone dimers with 17α-OH or 17β-OH (14α and 14β) as well as an androstenedione dimer (14). The new dimers and their respective precursors were tested on androgen-dependent (LNCaP) and androgen independent (PC3 and DU145) prostate cancer cells. It was discovered that the most active dimer was made of the natural hormone testosterone (14β) with an average IC₅₀ of 13.3 μM. In LNCaP cells, 14β was ∼5 times more active than the antiandrogen drug cyproterone acetate (IC₅₀ of 12.0 μM vs. 59.6 μM, respectively). At low concentrations (0.25-0.5 μM), 14α and 14β were able to completely inhibit LNCaP cell growth induced by testosterone or dihydrotestosterone. Furthermore, cross-reactivity of androgen-based dimers with sterol-metabolizing cytochrome P450 3A4 was explored and the results are disclosed herein.

Relevance of iNOS expression in tumor growth and maintenance of cancer stem cells in a bladder cancer model

The expression of inducible nitric oxide (NO) synthase (iNOS) in human bladder cancer (BC) is a poor prognostic factor associated with invasion and tumor recurrence. Here, we evaluated the relevance of iNOS expression in BC progression and in cancer stem cell (CSC) maintenance in a murine BC model. Also, iNOS expression and CSC markers were analyzed in human BC samples. iNOS inhibitors (L-NAME or 1400W) or shRNA were used on murine BC model with different iNOS expressions and invasiveness grades: MB49 (iNOS+, non-muscle invasive (NMI)) and MB49-I (iNOS++, muscle invasive (MI)), in order to analyzed cell proliferation, tumor growth, angiogenesis, number of CSC, and pluripotential marker expression. iNOS, SOX2, Oct4, and Nanog expressions were also analyzed in human BC samples by qPCR and immunohistochemistry. iNOS inhibtion reduced parameters associated with tumor progression and reduced the number of CSC, wich resulted higher in MB49-I than in MB49, in concordance with the higher expression of SOX2, Oct4, and Nanog. The expression of SOX2 was notoriously diminished, when iNOS was inhibited only in the MI cell line. Similar results were observed in human samples, where MI tumors expressed higher levels of iNOS and pluripotential genes, in comparison to NMI tumors with a positive correlation between those and iNOS, suggesting that iNOS expression is associated with CSC. iNOS plays an important role in BC progression and CSC maintenance. Its inhibition could be a potential therapeutic target to eradicate CSC, responsible for tumor recurrences. KEY MESSAGES: • iNOS expression is involved in bladder tumor development, growth, and angiogenesis. • iNOS expression is involved in bladder cancer stem cell generation and maintenance, playing an important role regulating their self-renewal capacity, especially in muscle invasive murine bladder cancer cells. • iNOS expression is higher in human muscle invasive tumors, in association with a high expression of pluripotential genes, especially of SOX2.

Locating the binding sites of two aminobenzoic acid derivatives on tRNA: drug binding efficacy and RNA structure

The binding of tRNA to aminobenzoic acid derivatives DAB-0 (N'-[4-(2,5-dioxo-pyrrolidin-1-yl)-benzoyl]-hydrazine carboxylic acid tert-butyl ester) and DAB-1 (N'-[4-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-benzoyl]-hydrazine carboxylic acid tert-butyl ester) was investigated in aqueous solution at physiological pH. Thermodynamic parameters ΔH⁰ -4.8 to -4.30 (kJ mol^-1), ΔS⁰ 24.20 to 22 (J mol^-1K^-1) and ΔG⁰ -12 to -11.40 (kJ mol^-1) showed that DAB-0 and DAB-1 readily bind tRNA via ionic interactions with DAB-1 forming stronger tRNA adducts. Similar binding sites to A-T and G-C bases were located with DAB-0 and DAB-1. The binding efficacy ranged from 40% to 50%. No alteration of tRNA conformation was detected upon drug complexation. Communicated by Ramaswamy H. Sarma.

Binding efficacy of aminobenzoic acid derivatives with DNA duplex: drug binding sites and DNA structure and dynamics

Communicated by Ramaswamy H. Sarma.

Leukemia inhibitory factor regulates the activation of inflammatory signals in macrophages and trophoblast cells

The pleiotropic cytokine leukemia inhibitory factor (LIF) is a key gestational factor known to establish dynamic cellular and molecular cross talk at the feto-maternal interface. Previously, we described the regulatory role of the LIF-trophoblast-IL10 axis in the process of macrophage deactivation in response to pro-inflammatory cytokines. However, the direct regulatory effects of LIF in macrophage and trophoblast cell function remains elusive. In this study, we aimed to examine whether and how LIF regulates the behavior of macrophages and trophoblast cells in response to pro-inflammatory stress factors. We found that LIF modulated the activating effects of interferon-gamma (IFNγ) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in macrophages and trophoblast cells by reducing the phosphorylation levels of signal transducer and activator of transcription-1 (Stat1) and -5 (Stat5). Cell activation with IFNγ inhibited cell invasion and migration but this immobilizing effect was abrogated when macrophages and trophoblast cells were deactivated with LIF; macrophage cell motility restitution could in part be explained by the positive effects of LIF in Stat3 activation and matrix metalloproteinase 9 (MMP-9) expression. Pharmacological inhibition of Stat1 and Stat3 indicated that IFNγ-induced Stat1 activation mediated macrophage motility inhibition, and that cell motility in IFNγ-activated macrophages is restored via LIF-induced Stat3 activation and Stat1 inhibition. Moreover, IFNγ-induced TNFα gene expression was also abrogated by LIF through Stat1 inhibition and Stat3 activation. Finally, we have found that cell invasion of trophoblast cells is inhibited when they were cocultured with GM-CSF-differentiated, IFNγ-stimulated macrophages. This effect, however, was inhibited when macrophages were exposed to LIF. Overall, this in vitro study reveals for the first time the anti-inflammatory and pro-gestational activities of LIF by acting directly on macrophages and trophoblast cells.

Biomolecular study and conjugation of two para-aminobenzoic acid derivatives with serum proteins: drug binding efficacy and protein structural analysis

Two aminobenzoic acid derivatives DAB-0 and DAB-1 showed distinct biological properties on murine bladder cancer (BCa) cell line MB49-I. In contrast to DAB-1, DAB-0 does not possess any anti-inflammatory activity and is less toxic. Furthermore, DAB-0 does not interfere with INFγ-induced STAT1 activation and TNFα-induced IκB phosphorylation, while DAB-1 does. In order to rationalize these results, the binding efficacy of DAB-0 and DAB-1 with serum proteins such a human serum albumin (HSA), bovine serum albumin (BSA) and beta-lactoglobulin (β-LG) was investigated in aqueous solution at physiological pH. Multiple spectroscopic methods and thermodynamic analysis were used to determine the binding efficacy of DAB-0 and DAB-1 with serum proteins. Drug-protein conjugation was observed via through ionic contacts. DAB-1 forms stronger adducts than DAB-0, while β-LG shows more affinity with the order of stability β-LG > BSA > HSA. The stronger complexation of DAB-1 with serum proteins might account for its biological potential and transport in the blood. The binding efficacy ranged from 40 to 60%. Major alterations of protein secondary structures were detected upon drug complexation. Serum proteins are capable of delivering DAB-1 in vitro.Communicated by Ramaswamy H. Sarma.

Molecular therapy with derivatives of amino benzoic acid inhibits tumor growth and metastasis in murine models of bladder cancer through inhibition of TNFα/NFΚB and iNOS/NO pathways

Muscle-invasive bladder cancer (MIBC) is an aggressive form of urothelial bladder carcinoma (UBC) with poorer outcomes compared to the non-muscle invasive form (NMIBC). Higher recurrent rates and rapid progression after relapse in UBC is known to be linked with chronic inflammation. Here, the preclinical murine models of NMIBC (MB49) and MIBC (MB49-I) were used to assess the antitumor effects of DAB-1, an anti-inflammatory aminobenzoic acid derivative we have developed in order to target cancer-related inflammation. A subchronic toxicity study on cancer-free mice shown that DAB-1 treatment did not affect normal mouse development or normal function of vital organs. In mice bearing MB49-I tumors, whole body accumulation of the radioconjugate [¹³¹I]DAB-1 was higher than in control mice, the main sites of [¹³¹I]DAB-1 accumulation being the liver (34%), the intestines (21%), and the tumors (18%). In vivo molecular therapy of ectopic and orthotopic tumors indicated that treatment with DAB-1 efficiently inhibited tumor growth, metastasis formation, and mortality rate. The antitumor efficacy of DAB-1 was associated with strong decreased tumor cell proliferation and iNOS expression in tumor tissues and deactivation of macrophages from tumor-bearing mice. Mechanistic investigations revealed that DAB-1 efficiently inhibited i) TNFα/NFΚB and IL6/STAT3 signaling pathways activation; ii) TNFα-induced NO production by decreasing NFΚB transcriptional activation and functional iNOS expression; and iii) cellular proliferation with minimal or no effects on cell mortality or apoptosis. In conclusion, this study provides preclinical and biological/mechanistic data highlighting the potential of DAB-1 as a safe and efficient therapeutic agent for the treatment of patients with NMIBC and MIBC.

Optimal germination condition impacts on the antioxidant activity and phenolic acids profile in pigmented desi chickpea (Cicer arietinum L.) seeds

Legume sprouts are considered natural, healthy products that provide a source of bioactive compounds to fight against chronic diseases. This study aims to identify the optimal germination temperature (GT) and germination time (Gt) to maximize total phenolic and flavonoid contents (TPC, FC), and antioxidant activity (AoxA) of desi chickpea. Response surface methodology was used as an optimization tool. An experimental design with two factors (GT and Gt) and five levels was used (13 treatments). The sprouts from each treatment were lyophilized, tempered, and milled to obtain germinated chickpea flours (GCF). To predict the phytochemicals composition and AoxA in GCF, regression models were developed. Maximum TPC, FC, and AoxA were attained during germination 33.7 °C for 171 h. Optimized germinated chickpea flour produced applying the optimal germination conditions resulted in an increase of protein and total dietary fibre content, TPC, FC, phenolic acids profile, and AoxA. Germination at optimal conditions also increased the level of coumaric, ferulic, synapic, ellagic, and syringic acids. This study demonstrated that germination carried out under optimal conditions enhanced the nutraceutical value of desi chickpea seeds.

Chemical composition and physicochemical properties of Phaeodactylum tricornutum microalgal residual biomass

The production of photosynthetic biofuels using microalgae is a promising strategy to combat the use of non-renewable energy sources. The microalgae residual biomass is a waste by-product of biofuel production; however, it could prove to have utility in the development of sustainable nutraceuticals and functional foods. In this study, a comprehensive characterisation of the under-utilised Phaeodactylum tricornutum microalgae residual biomass is presented. Proximal composition, antioxidant capacity (using three different antioxidant assays; oxygen radical absorbance capacity; radical cation activity, ABTS; and radical scavenging activity, DPPH), and total phenolic content of free and bound polyphenols were determined. Additionally, the physicochemical properties of water activity, pH, water absorption index, water solubility index, and dispersibility were evaluated. Results revealed that P. tricornutum microalgae residual biomass exhibits a relatively high protein and carbohydrate content, with values of 36.67% and 46.78%, respectively; and most carbohydrates were found as total dietary fibre (45.57%), of which insoluble dietary fibre was the most predominant (43.54%). Antioxidant capacity values for total phytochemicals of 106.22, 67.93, 9.54 µM TE g^-1 dw were determined by oxygen radical absorbance capacity, ABTS, and DPPH assays, respectively. Total phenolic content was found to be 2.90 mg GAE g^-1 dw. Interestingly, antioxidant capacity and total phenolic content were higher in bound than in free phytochemical extracts. The physicochemical analysis showed P. tricornutum microalgae residual biomass to have suitable properties for the generation of a beverage with Aw, pH, water absorption index, water solubility index, and dispersibility values of 0.45, 7.12, 3.40 g gel g^-1 dw, 2.5 g solids 100 g^-1 dw, and 90%, respectively. Hence, P. tricornutum microalgae residual biomass could be considered a potential source of bioactive compounds suitable for the production of functional food exhibiting antioxidant capacity and high dietary fibre content.

Composición química y calidad nutritiva de garbanzo (Cicer arietinum L.) fresco y endurecido después de la fermentación en estado sólido (FES)/Chemical composition and nutritional quality of fresh and hardened chickpea (Cicer arietinum L) after the solid state fermentation (SSF)

Solid state fermentation (SSF) represents a technological alternative for a great variety of legumes and cereals, or combinations of them, to improve their nutritional quality and to obtain edible products with palatable sensorial characteristics. Chickpeas (Cicer arietinum L.) are prone to develop the hardening phenomenon, also known as hard-to-cook (HTC) defect, when stored under adverse conditions of high temperature (≥ 25 °C) and high relative humidity (≥ 65%). This hard-to-cook phenomenon causes increases in cooking time, decreases in nutritional quality and deterioration of sensorial attributes of chickpea. The objective of this work was to study the effect of SSF on chemical composition and nutritional quality of fresh and hardened chickpeas. The hardening of chickpea ( Cicer arietinum L. Blanco Sinaloa 92 variety) for human consumption, was produced by accelerated storage (33-35 °C, RH = 75%, 180 days). A Rhizopus stolonifer spore suspension (1 x 106 spores/mL) was used as starter for the fermentation. The temperature and time of the SSF process were 35.8 °C and 42.7 h, respectively. The tempeh was obtained from fresh and hardened chickpea. The SSF process caused a significant increase ( p ≤ 0.05) in crude protein, true protein (19.6-19.9 to 23.2-23.4%), protein solubility, in vitro digestibility (68.6-73.1% to 79.9-80.5%), available lysine (2.19-3.04 to 3.19-4.07 g lysine/ 16 N), palmitic acid, and stearic acid, and a significant decrease ( p ≤ 0.05) in lipids, minerals, linoleic acid, phytic acid (8.82-10.73 to 2.11 g phytic acid/g dry matter), and tannins (16.1-22.4 to 3 mg catechin/g dry matter). The SSF process improved significantly the quality of fresh and hardened chickpea.

Influencia del almacenamiento a temperatura y humedad relativa altas sobre la calidad de garbanzo (C icer arietinum L.) Influence of storage at high temperature and high relative humidity on seed quality of chickpea ( Cicer arietinum L.)

The effect of storage simulating tropical conditions (33-35°C, RH = 75%, 160 days) on seed quality of three chickpea (Cicer arietinum L) varieties for human consumption (Surutato 77, Mocorito 88, and Blanco Sinaloa 92) was studied. Storage induced the hard to cook (HTC) condition in all samples. For all samples, the Hunter L value decreased (p < 0.05) and the total difference in color (AE) increased (p < 0.05) during storage, meaning a loss of color lightness and development of darkening. Accelerated storage caused a significant decrease (p < 0.05) in the water absorption capacity (WAC) and cooking time (CT) of whole seed, cotyledons and seed coat for all samples,; these changes were more pronounced for the Blanco Sinaloa variety. Furthermore, storage produced significant (p < 0.05) decreases in the seed coat tannin content of the three materials; this parameter increased (11 < 0.05) in cotyledons. In all samples, the levels of phytic acid in cotyledons decreased (y < 0.05) with the seed hardness. Hardening of chickpea seeds caused a decrease (y < 0.05) in the in vitro protein digestibility of all varieties. These results allow us to suggest that both cotyledons and seed coat play a significant role in the process of chickpea hardening. Blanco Sinaloa 92 and Mocorito 88 might be classified as varieties with high and low proneness, respectively, to develop the HTC condition.

Transmission efficiency of tomato apex necrosis virus by Bemisia tabaci (Hemiptera: Aleyrodidae) biotype B in tomato

Tomato apex necrosis virus (ToANV) is a new virus that causes important damage in tomato crops from the Culiacan Valley, Sinaloa, Mexico. To understand the relationship between ToANV and its vector Bermisia tabaci (Hemiptera: Aleyrodidae) (Gennadius) biotype B, laboratory and greenhouse trials were completed to: 1) determine the acquisition and inoculation access periods of ToANV by B. tabaci from tomato to tomato, 2) understand the transmission efficiency at different B. tabaci population densities, 3) estimate the time from inoculation of the virus at different B. tabaci densities to manifestation of symptoms in the plants, and 4) determine the retention time of the virus by the insect vector. The presence of the virus in plants was determined by reverse transcription-polymerase chain reaction amplification ofa 795-bp fragment (GenBank JN704068), which is phylogenetically related to ToANV (GenBank EF063242). The results showed that B. tabaci is an effective vector for ToANV with relatively long acquisition (12 h) and inoculation (9 h) access periods; a single adult is capable of transmitting and retaining the virus for up to 7d, suggesting a persistent mode of transmission. These results will help in the development of management strategies for controlling the vector and the disease.

The V86M mutation in HIV-1 capsid confers resistance to TRIM5α by abrogation of cyclophilin A-dependent restriction and enhancement of viral nuclear import

Background

HIV-1 is inhibited early after entry into cells expressing some simian orthologues of the tripartite motif protein family member TRIM5α. Mutants of the human orthologue (TRIM5α_hu) can also provide protection against HIV-1. The host protein cyclophilin A (CypA) binds incoming HIV-1 capsid (CA) proteins and enhances early stages of HIV-1 replication by unknown mechanisms. On the other hand, the CA-CypA interaction is known to increase HIV-1 susceptibility to restriction by TRIM5α. Previously, the mutation V86M in the CypA-binding loop of HIV-1 CA was found to be selected upon serial passaging of HIV-1 in cells expressing Rhesus macaque TRIM5α (TRIM5α_rh). The objectives of this study were (i) to analyze whether V86M CA allows HIV-1 to escape mutants of TRIM5α_hu, and (ii) to characterize the role of CypA in the resistance to TRIM5α conferred by V86M.

Results

We find that in single-cycle HIV-1 vector transduction experiments, V86M confers partial resistance against R332G-R335G TRIM5α_hu and other TRIM5α_hu variable 1 region mutants previously isolated in mutagenic screens. However, V86M HIV-1 does not seem to be resistant to R332G-R335G TRIM5α_hu in a spreading infection context. Strikingly, restriction of V86M HIV-1 vectors by TRIM5α_hu mutants is mostly insensitive to the presence of CypA in infected cells. NMR experiments reveal that V86M alters CypA interactions with, and isomerisation of CA. On the other hand, V86M does not affect the CypA-mediated enhancement of HIV-1 replication in permissive human cells. Finally, qPCR experiments show that V86M increases HIV-1 transport to the nucleus of cells expressing restrictive TRIM5α.

Conclusions

Our study shows that V86M de-couples the two functions associated with CA-CypA binding, i.e. the enhancement of restriction by TRIM5α and the enhancement of HIV-1 replication in permissive human cells. V86M enhances the early stages of HIV-1 replication in restrictive cells by improving nuclear import. In summary, our data suggest that HIV-1 escapes restriction by TRIM5α through the selective disruption of CypA-dependent, TRIM5α-mediated inhibition of nuclear import. However, V86M does not seem to relieve restriction of a spreading HIV-1 infection by TRIM5α_hu mutants, underscoring context-specific restriction mechanisms.

CD40 pathway activation reveals dual function for macrophages in human endometrial cancer cell survival and invasion

Reproductive malignancies are a major cause of cancer death in women worldwide. CD40 is a TNF receptor family member, which upon activation may mediate tumor regression. However, despite the great potential of CD40 agonists, their use as a therapeutic option for reproductive cancers has never been investigated. Because CD40 ligation is a potent pathway of macrophage activation, an in vitro model of pro-inflammatory type-1 (Mϕ-1) and anti-inflammatory type-2 (Mϕ-2) macrophages was developed to determine whether and how macrophage CD40 pathway activation might influence endometrial tumor cell behavior. Analysis of tumor growth kinetic in the endometrial cancer xenograft model indicates that, when injected once into the growing tumors, CD40-activated Mϕ-1 greatly reduced, while CD40-activated Mϕ-2 increased tumor size when compared to control isotype-activated Mϕ-1 and Mϕ-2, respectively. In vitro assays indicated that CD40-activated Mϕ-2 increased cell viability but failed to promote cell invasion. CD40-activated Mϕ-1, in contrast, decreased cell survival but greatly increased cell invasion in tumor cells less susceptible to cell death by apoptosis; they also induced the expression of some pro-inflammatory genes, such as IL-6, LIF, and TNF-α, known to be involved in tumor promotion and metastasis. The presence of IFN-γ is minimally required for CD40-activated Mϕ-1 to promote tumor cell invasion, a process that is mediated in part through the activation of the PI3K/Akt2 signaling pathway in tumor cells. From these results, we speculate that some functions of CD40 in tumor-associated Mϕs might limit the therapeutic development of CD40 agonists in endometrial cancer malignancies.

Lantana macrophylla Schauer (Verbenaceae) ethanolic extract induces activation of ERK1/2 and p38 MAPKs pathway and Ca2+ imbalance in human trophoblasts derived cell lines

Lantana macrophylla Schauer (Verbenaceae) a medicinal plant used to treat menstrual and respiratory disorders was investigated. The ethanolic extract from leaves was subjected to phytochemical and biological analysis. BeWo and JEG-3 cells were used to evaluate human chorionic gonadotropin hormone (hCG) production, syncytial formation, Ca2+ uptake and Ca2+ handling protein expression. The cAMP production and the mitogen-activated protein kinases (MAPKs) phosphorylation were also investigated. Phytochemical analysis yield three triterpenes: oleanolic, ursolic and latonolic acid. Viability assay showed no significant cytotoxic effect. A significant decrease in hCG production but not a disturbance on BeWo cell fusion were observed. The cAMP pathway was not affected by L. macrophylla extract alone; although the cAMP production inducted by forskolin was diminished. Both ERK1/2 and p38 MAPKs pathways were activated. Increased intracellular Ca2+ concentration ([Ca2+]i) was observed after 24 h treatment in a time and dose dependent manner; however only L. macrophylla at 10 μg/mL induced increased [Ca2+]i after 10 min treatment. CaBP28K and PMCA1/4 were modulated at protein and mRNA levels, respectively. This study showed for the first time the effect of triterpenoids from L. macrophylla leaves on trophoblasts-like cells and indicates a potential toxic effect of this plant in the placental development and fetal growth.

Physicochemical, Nutritional and Antioxidant Properties of Tempeh Flour from Common Bean ( Phaseolus vulgaris L.)

The effects of solid state fermentation (SSF) on physicochemical, nutritional and antioxidant properties of common bean flour were studied. SSF increased protein content (21.7%) and decreased lipids (-38.4%), carbohydrates (-3.5%) and phytic acid (-58.3%). Fermented (tempeh) flour showed higher dispersability, lower water solubility index and pH than unfermented flour. Fermentation also increased an average of 0.21 g/100 g protein, six of the essential amino acids (EAAs), including total sulfur (Met + Cys), the limiting EAAs in unfermented flour (score = 0.91); Lys and Trp decreased 0.21 and 0.09 g/100 g protein, respectively. SSF improved the in vitro protein digestibility and the calculated protein efficiency ratio. Tempeh flour had 2.2-fold more phenolics than the bean flour and exhibited antiradical activity (43%) and antioxidant activity (38%) correlated with total phenolics content. Common bean tempeh flour may be considered for the fortification of widely consumed legume-based food products and also for the prevention of pathologies associated with oxidative stress.

Requirement of Oxidation-dependent CD40 Homodimers for CD154/CD40 Bidirectional Signaling

It is well established that the CD154/CD40 interaction is required for T cell-dependent B cell differentiation and maturation. However, the early molecular and structural mechanisms that orchestrate CD154 and CD40 signaling at the T cell/APC contact site are not well understood. We demonstrated that CD40 engagement induces the formation of disulfide-linked (dl) CD40 homodimers that predominantly associate with detergent-resistant membrane microdomains. Mutagenesis and biochemical analyses revealed that (a) the integrity of the detergent-resistant membranes is necessary for dl-CD40 homodimer formation, (b) the cytoplasmic Cys(238) of CD40 is the target for the de novo disulfide oxidation induced by receptor oligomerization, and (c) dl-CD40 homodimer formation is required for CD40-induced interleukin-8 secretion. Stimulation of CD154-positive T cells with staphylococcal enterotoxin E superantigen that mimics nominal antigen in initiating cognate T cell/APC interaction revealed that dl-CD40 homodimer formation is required for interleukin-2 production by T cells. These findings indicate that dl-CD40 homodimer formation has a physiological role in regulating bidirectional signaling.

Nutritional properties of quality protein maize and chickpea extruded based weaning food

Malnutrition is one of the major causes of morbidity and mortality among young children in most of the developing countries. To minimize the adversities of malnutrition, low-cost infant supplementary foods have been developed and are being supplied to the needy through state-sponsored nutrition intervention programmers. The present study had two objectives: to determine the best combination of nixtamalized extruded quality protein maize (NEMF) and extruded chickpea (ECF) flours for producing a weaning food, and to evaluate the nutritional properties of the optimized NEMF/ECF mixture and the weaning food. The NEMF and ECF were produced applying combinations of extrusion temperature/screw speed of 79.4 degrees C/73.5 rpm, and 150.5 degrees C/190.5 rpm, respectively. Response surface methodology was applied to determine the optimum combination NEMF/ECF; the experimental design generated 11 assays. Mixtures from each assay were evaluated for true protein (TP) and available lysine (AL). Each one of 11 mixtures were used for preparing 11 weaning foods which were sensory evaluated for acceptability (A). The best combination of NEMF/ECF for producing a weaning food was NEMF = 21.2%/ ECF = 78.8 %. This mixture had a global desirability (D) of 0.93; it contained 20.07% proteins (DM), 5.70% lipids (DM), and 71.14% carbohydrates (DM); its essential amino acids (EAA) profile satisfactorily covered the EAA requirements for children 2-5 years old, except for Trp. The weaning food prepared with the optimized mixture had high protein quality and digestibility and could be used to support the growth of infants.

Spermatozoa modulate epididymal cell proliferation and protein secretion in vitro

Normal epididymal function, such as protein expression and secretion, is primarily regulated by testicular androgens and temperature. However, the role of spermatozoa in this critical process has never been studied. In order to determine whether sperm itself could regulate epididymal function, we have developed a cell culture system of bovine epididymal cells to study the interactions between spermatozoa and the epididymal epithelium. Primary cells from caput, corpus, and cauda epididymal tissues were cultured in the presence of androgens at 32 degrees C (scrotal) and 37 degrees C (abdominal). Newly synthesized proteins were metabolically labeled with (35)S-methionine after sperm co-incubation and the pattern of secreted proteins was analyzed by two-dimensional polyacrylamide gel electrophoresis. Proliferation rate, protein secretion rate and electrophoretic patterns of secreted proteins were evaluated 48 hr post-co-incubation. Incubation at 32 degrees C indicated that spermatozoa stimulation increases the level of protein secretion of cultured cells from all epididymal sections while it slightly decreases proliferation of corpus cells. At 37 degrees C, spermatozoa co-incubation significantly decreases the protein secretion rate of cultured cells from all epididymal sections. Independently of cell incubation temperature, spermatozoa stimulation induces both an increase in the intensity of radiolabeled proteins and the appearance of new secreted proteins of caput cells without affecting the protein pattern of corpus or cauda cells. Incubation at 37 degrees C, however, greatly modifies the pattern of proteins expressed at 32 degrees C by cauda cells. Taken together, these results support the hypothesis that spermatozoa themselves affect epididymal cell function, most importantly for caput epididymides.

CD40 ligand binds to alpha5beta1 integrin and triggers cell signaling

It was originally thought that the critical role of the CD40 ligand (CD40L) in normal and inflammatory immune responses was mainly mediated through its interaction with the classic receptor, CD40. However, data from CD40L(-/-) and CD40(-/-) mice suggest that the CD40L-induced inflammatory immune response involves at least one other receptor. This hypothesis is supported by the fact that CD40L stabilizes arterial thrombi through an alphaIIbbeta3-dependent mechanism. Here we provide evidence that soluble CD40L (sCD40L) binds to cells of the undifferentiated human monocytic U937 cell line in a CD40- and alphaIIbbeta3-independent manner. Binding of sCD40L to U937 cells was inhibited by anti-CD40L monoclonal antibody 5C8, anti-alpha5beta1 monoclonal antibody P1D6, and soluble alpha5beta1. The direct binding of sCD40L to purified alpha5beta1 was confirmed in a solid phase binding assay. Binding of sCD40L to alpha5beta1 was modulated by the form of alpha5beta1 expressed on the cell surface as the activation of alpha5beta1 by Mn(2+) or dithiothreitol resulted in the loss of sCD40L binding. Moreover, sCD40L induced the translocation of alpha5beta1 to the Triton X-100-insoluble fraction of U937 cells, the rapid activation of the MAPK pathways ERK1/2, and interleukin-8 gene expression. The binding of sCD40L to CD40 on BJAB cells, an alpha5beta1-negative B cell line, and the resulting activation of ERK1/2 was not inhibited by soluble alpha5beta1, suggesting that sCD40L can bind concomitantly to both receptors. These results document the existence of novel CD40L-dependent pathways of physiological relevance for cells expressing multiple receptors (CD40, alpha5beta1, and alphaIIbbeta3) for CD40L.

Infant food from quality protein maize and chickpea: optimization for preparing and nutritional properties

The present study had two objectives: to determine the best combination of nixtamalized maize flour (NMF) from quality protein maize and extruded chickpea flour (ECF) for producing an infant food, and to evaluate the nutritional properties of the optimized NMF/ECF mixture and the infant food. Response surface methodology (RSM) was applied to determine the best combination of NMF/ECF; the experimental design (Lattice simplex) generated 11 assays. Mixtures from each assay were evaluated for true protein and available lysine. Each one of 11 mixtures was used for preparing 11 infant foods that were sensory evaluated for acceptability. A common optimum value for the three response variables was obtained utilizing the desirability method. The best combination of NMF/ECF for producing an infant food was NMF = 26.7%/ECF = 73.3%; this optimized mixture had a global desirability of 0.87; it contained 19.72% dry matter (DM) proteins, 6.10% (DM) lipids, 71.45% (DM) carbohydrates, and 2.83% (DM) minerals; its essential amino acids profile covered the amino acids requirements for children 10-12 years old. The infant food prepared from optimized mixture had an in vitro protein digestibility of 87.9%, and a calculated protein efficiency ratio of 1.86. Infant food could be used to support the growth of infants in developing countries.

The proacrosin binding protein, sp32, is tyrosine phosphorylated during capacitation of pig sperm

Mammalian sperm must undergo capacitation, a preparation period in the female reproductive tract or in vitro, in order to fertilize. We have previously described a Mr 32 000 tyrosine phosphorylated protein, "p32," that appears in pig sperm during capacitation. The identity of p32 remains unknown; if and how it is involved during capacitation is not understood. The objective of the present study was to identify p32 by proteomic techniques. Western blotting of proteins separated successively under nonreducing and then reducing conditions showed the appearance of the tyrosine phosphorylated p32 only when sperm were incubated in capacitating conditions. The spot was sequenced by mass spectrometry/mass spectrometry and identified as "sp32," a protein implicated in proacrosin maturation. The same membranes probed with anti-sp32 antibody demonstrated that sp32 is present in both noncapacitating and capacitating conditions and revealed exactly the same spot as p32. Immunoprecipitation with either anti-phosphotyrosine or anti-sp32 antibody corroborated these results. Indirect immunofluorescence with anti-phosphotyrosine antibody or anti-sp32 antibody show similar labeling of capacitated sperm, supporting the hypothesis that p32 is a tyrosine phosphorylated form of sp32. After ionophore treatment to induce the acrosome reaction, anti-sp32 and anti-phosphotyrosine labeling on the acrosome disappeared. These results demonstrate that sp32, a (pro)acrosin binding protein, is the p32, a tyrosine phosphorylated protein related to capacitation. We will now focus on the significance of tyrosine phosphorylation on sp32 function during fertilization-related events.

Use of phosphoproteomics to study tyrosine kinase activity in capacitating boar sperm

It is generally accepted that sperm capacitation is associated with the protein kinase A-mediated appearance of tyrosine phosphoproteins, although the substrates and kinase(s) involved have not been identified. We described a Mr 32,000 tyrosine phosphoprotein, "p32", appearing in porcine sperm coincident with capacitation. We also discovered a tyrosine kinase-like enzyme in boar sperm of Mr 32,000 ("TK-32") with enhanced activity during capacitation. The present work was conducted to further characterize and to identify these capacitation-related protein(s). Fresh porcine sperm were incubated to induce capacitation then immunoprecipitation, immunoblotting and proteomic analysis revealed seven tyrosine-phosphorylated proteins aligned in the range of Mr 30,000 with different isoelectric pH values (pI). Therefore, p32 may be composed of several tyrosine phosphoproteins. Three were identified as acrosin-binding sp32 (pI 6.5), and two triosephosphate isomerase isoforms (pI 7.1 and 7.9). At present, however, proteonomic analysis has not revealed any kinase at Mr 32,000. Immunoprecipitation experiments show that p32 and TK-32 are different molecules, as TK-32 activity remains in the supernatant of the antiphosphotyrosine precipitates. Finally, in-gel renaturation and immunoblotting suggest that TK-32 is a mitogen-activated protein kinase (MAPK). The discovery of p32 and the MAPK-like TK-32 provides new insight regarding the mechanisms underlying capacitation in the pig.

Requirement of the extracellular cysteine at position six for CD40/CD40 dimer formation and CD40-induced IL-8 expression

We recently showed that oligomerization of CD40 molecules on cell surface leads to disulfide-linked CD40/CD40 dimer formation, an event that is necessary for CD40-induced B7-2 expression in human B cells. Here, we demonstrate that CD40/CD40 dimers formation also occurs in different cell types such as T24 bladder cancer cells and CD40-transfected HEK 293 cells. Disulfide bonds mediate the formation of CD40/CD40 homodimers in CD40-activated cells. To determine the potential residue(s) involved in disulfide bonds formation and subsequent CD40-induced IL-8 expression, we generated a CD40 mutant in which the extracellular cysteine 6 was replaced by a glutamine (CD40-C6Q). CD40-induced IL-8 mRNA expression and protein synthesis were studied in stably transfected HEK 293 cells that were sorted out along with similar levels of expression of wild type (CD40-WT) and CD40-C6Q molecules. In contrast to cells expressing CD40-WT protein, disulfide-linked CD40/CD40 dimer formation was completely abolished in HEK 293 cells expressing CD40-C6Q proteins. Abolishment of disulfide-linked CD40/CD40 dimers in these transfected cells was sufficient to inhibit CD40-induced mRNA expression and secretion of IL-8. This study identifies the extracellular cysteine 6 of CD40 molecules as a potential molecular target to disrupt the expression of CD40-induced pro-inflammatory cytokines by epithelial cells.

Boar sperm storage capacity of BTS and Androhep Plus: viability, motility, capacitation, and tyrosine phosphorylation

Androhep Plus, a long-term extender (up to 7 days) and Beltsville Thawing Solution (BTS), a short-term extender (up to 3 days), are commonly used for liquid storage of porcine semen. To test the hypothesis that modifications in sperm viability, motility, chlortetracycline (CTC) fluorescence patterns, and protein tyrosine phosphorylation occur during semen storage in extenders, we compared these end points at different periods of storage in either Androhep Plus or BTS. Sperm from five boars were assessed daily over 12 days of storage (n = 5 ejaculates from different boars). Viability was not different (P < 0.05 between extenders, except on Day 2, when Androhep Plus maintained better viability. Differences in the percentage of motile (total) sperm due to extender were evident on Days 2, 4, 5, and 6, when Androhep Plus was superior to BTS (P < 0.05). The percentages of progressively motile sperm also differed, with Androhep Plus supporting higher rates on Days 2, 4, 5, 7, 8, 9, 10, and 11 (P < 0.05). The CTC fluorescence pattern distribution differed due to extender as early as Day 2; storage in Androhep Plus induced higher levels of pattern B sperm (P < 0.05) than storage in BTS. A tyrosine-phosphorylated protein of Mr 21,000 appeared after 10 days in sperm incubated in BTS, and was identified as a phospholipid hydroperoxide glutathione peroxidase. Therefore, modifications in viability, motility, CTC fluorescence patterns, and sperm protein tyrosine phosphorylation were apparent during sperm storage in extenders; these may affect the fertilizing capacity of the semen.

Localization of the chaperone proteins GRP78 and HSP60 on the luminal surface of bovine oviduct epithelial cells and their association with spermatozoa

Upon their transit through the female genital tract, bovine spermatozoa bind to oviduct epithelial cells, where they are maintained alive for long periods of time until fertilization. Although carbohydrate components of the oviduct epithelial cell membrane are involved in these sperm/oviduct interactions, no protein candidate has been identified to play this role. To identify the oviduct factors involved in their survival, sperm cells were preincubated for 30 min with apical membranes isolated from oviduct epithelial cells, washed extensively, and further incubated for up to 12 h in the absence of apical membranes. During this incubation, sperm viability, motility, and acrosomal integrity were improved compared with cells preincubated in the absence of apical membranes. This suggests that, during the 30-min preincubation with apical membrane extracts, either an oviductal factor triggered intracellular events resulting in positive effects on spermatozoa or that such a factor strongly attached to sperm cells to promote a positive action. Similarly, spermatozoa were incubated with apical membranes isolated from oviduct epithelial cells labeled with [35S]-methionine and, upon extensive washes, proteins were separated by two-dimensional (2-D) gel electrophoresis to identify the factors suspected to have beneficial effects on spermatozoa. The six major proteins, according to their signal intensity on the autoradiographic film, were extracted from a 2-D gel of oviduct epithelial cell proteins run in parallel and processed for N-terminal sequencing of the first 15 amino acids. Of these, one was identical to heat shock protein 60 (HSP60) and one to the glucose-regulated protein 78 (GRP78). Their identities and association with spermatozoa were confirmed using an antibody directed against these proteins. This paper reports the localization of both GRP78 and HSP60 on the luminal/apical surface of oviduct epithelial cells, their binding to spermatozoa, and the presence of endogenous HSP60 in the sperm midpiece.

Nixtamalized flour from quality protein maize (Zea mays L). optimization of alkaline processing

Quality of maize proteins is poor, they are deficient in the essential amino acids lysine and tryptophan. Recently, in Mexico were successfully developed nutritionally improved 26 new hybrids and cultivars called quality protein maize (QPM) which contain greater amounts of lysine and tryptophan. Alkaline cooking of maize with lime (nixtamalization) is the first step for producing several maize products (masa, tortillas, flours, snacks). Processors adjust nixtamalization variables based on experience. The objective of this work was to determine the best combination of nixtamalization process variables for producing nixtamalized maize flour (NMF) from QPM V-537 variety. Nixtamalization conditions were selected from factorial combinations of process variables: nixtamalization time (NT, 20-85 min), lime concentration (LC, 3.3-6.7 g Ca(OH)2/l, in distilled water), and steep time (ST, 8-16 hours). Nixtamalization temperature and ratio of grain to cooking medium were 85 degrees C and 1:3 (w/v), respectively. At the end of each cooking treatment the steeping started for the required time. Steeping was finished by draining the cooking liquor (nejayote). Nixtamal (alkaline-cooked maize kernels) was washed with running tap water. Wet nixtamal was dried (24 hours, 55 degrees C) and milled to pass through 80-US mesh screen to obtain NMF. Response surface methodology (RSM) was applied as optimization technique, over four response variables: In vitro protein digestibility (PD), total color difference (deltaE), water absorption index (WAI), and pH. Predictive models for response variables were developed as a function of process variables. Conventional graphical method was applied to obtain maximum PD, WAI and minimum deltaE, pH. Contour plots of each of the response variables were utilized applying superposition surface methodology, to obtain three contour plots for observation and selection of best combination of NT (31 min), LC (5.4 g Ca(OH)2/l), and ST (8.1 hours) for producing optimized NMF from QPM.

CD40/CD40 homodimers are required for CD40-induced phosphatidylinositol 3-kinase-dependent expression of B7.2 by human B lymphocytes

Preformed CD40/CD40 homodimers were initially observed on human Burkitt lymphoma cell lines, normal B cells, and transitional bladder carcinoma cell lines. However, the nature and the biological relevance of these homodimers have not yet been investigated. In the present study, we demonstrated that Epstein-Barr virus-transformed B cells and CD40-transfected HEK 293 cells constitutively expressed disulfide-linked CD40/CD40 homodimers at low levels. Oligomerization of CD40 leads to a rapid and significant increase in the disulfide-linked CD40/CD40 homodimer formation, a response that could be prevented using a thiol-alkylating agent. Formation of CD40/CD40 homodimers was found to be absolutely required for CD40-mediated activation of phosphatidylinositol 3-kinase, which, in turn regulated B7.2 expression. In contrast, CD40 monomers provided the minimal signal emerging from CD40, activating p38 MAP kinase and inducing homotypic B cell adhesion. CD40/CD40 homodimer formation was totally independent of TRAF1/2/3/5 associations with the threonine at position 254 in the cytoplasmic tail of the CD40 molecules. This finding may be vital to better understanding the molecular mechanisms that govern cell signaling triggered by CD40/CD154 interactions.

Characterization of secretory proteins from cultured cauda epididymal cells that significantly sustain bovine sperm motility in vitro

Epididymis provides a safe environment in which stored-spermatozoa could survive for days before ejaculation. In vitro studies suggested that epididymal proteins seem to be implicated in sperm survival during coincubation with cultured epididymal cells. This study was basically designed to confirm if secretory proteins from bovine epididymal cell cultures provide sperm protection against rapid loss of sperm motility in vitro. Bovine spermatozoa were incubated in conditioned media (CM), which were prepared from cultured cauda epididymal cell (CEC). Motion parameters were recorded using a computer-assisted sperm analyzer. Sperm-free protein extracts from CM were fractionated by ultrafiltration through a 10-kDa cut off membrane. A significantly positive effect on sperm motility was observed when spermatozoa were incubated in CM (54 +/- 4%) and CM > 10 kDa (57 +/- 4%) compared to CM < 10-kDa fraction (30 +/- 3%) or fresh media (34 +/- 3%), after a 6-hr incubation period. This beneficial effect on sperm motility was abolished when the CM > 10-kDa fraction was heat-treated at 100 degrees C for 10 min. The CM > 10 kDa fraction provides factors that remained active even though spermatozoa were washed twice after a 2-hr preincubation period. To identify potential beneficial factors, bovine spermatozoa were incubated with radiolabeled proteins obtained using (35)S-methionine in culture medium. SDS-PAGE analysis of proteins extracted from CM-preincubated spermatozoa revealed the presence of a 42-kDa protein strongly associated to the sperm surface. This 42-kDa spot was trypsin-digested and identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) as a protein homologue to a 35-kDa bovine estrogen-sulfotransferase. This protein can play a role in epididymal biology and sperm function. Taken together, these results suggest that specific epididymal proteins can be implicated in the sperm protection in vitro, and can be characterized in our cell culture system.

Characterization and identification of epididymal factors that protect ejaculated bovine sperm during in vitro storage

The role of secretory epididymal factors on sperm survival and storage in bovine cauda epididymides is poorly understood. Thus, the effects of bovine epididymal epithelium fluid (BEEF) on frozen-thawed bovine sperm motility have been evaluated in vitro. Sperm motion parameters were assessed by computer-assisted sperm analysis. Compared with serum bovine proteins, BEEF efficiently sustained bovine sperm motility after a 6-h incubation period. The positive effect of BEEF on sperm motility was even more apparent using a fractionated BEEF extract (>10 kDa, 2 mg/ml). This beneficial effect was abolished when the BEEF active fraction was heat treated before incubation. A minimal 2-h BEEF preincubation period was necessary to maintain sperm motility activity and to protect sperm against oxidative injury caused by 150 microM hydrogen peroxide. The proteins from the BEEF >10-kDa fractions were biotinylated to identify the proteins that bind to the sperm surface. Five specific sperm-surface-binding proteins were revealed by Western blot analysis probed with avidin-horseradish peroxidase conjugate. These proteins were digested with trypsin for identification by matrix-assisted laser desorption ionization time-of-flight peptide mass spectrometric analyzer. Under reducing conditions, 5 bovine proteins were identified: the beta (36-kDa spot) and alpha (38-kDa spot) chains of clusterin, the beta-adrenergic receptor kinase 2 (48-kDa spot), and the antithrombin-III and the fibrinogen gamma-B chains, both corresponding to a doublet of about 50-52 kDa. These proteins are known to be present at the sperm surface in other species and could play a role in sperm protection in vivo. These results provide new insights to explain how secretory epididymal proteins sustain sperm motility during storage in vitro.

Addition of specific metabolites to bovine epididymal cell culture medium enhances survival and motility of cryopreserved sperm

We have developed a cell culture system of bovine epididymal epithelium in which cryopreserved bovine sperm motility was efficiently maintained for many hours. The culture conditions to maintain viable epididymal cells are quite different from conditions normally used to incubate sperm cells. Thus, we have modified a previously described principal cell medium (PCM; Moore et al, 1992) using HEPES as a buffer and supplemented media with myo-inositol, pyruvate, lactate, glycerol, and carnitine to mimic epididymal intraluminal conditions. In the first experiments the effects of PCM and our epididymal cell medium (ECM) on sperm motility were compared in the absence of cells and evaluated by microscopic analysis under a phase contrast microscope or using the Hamilton Thorn Image Analyzer System. Our results showed that motility of cauda epididymal sperm was significantly higher in ECM than in PCM during a 48-hour incubation period when both media were supplemented with 10% fetal bovine serum (FBS). We then replaced FBS with bovine serum albumin (BSA) or no proteins at all to verify if ECM was able to enhance sperm survival. To test this aspect we used frozen-thawed sperm, which survived up to 48 hours when sperm cells were coincubated with epididymal cell monolayers. Hence, PCM, ECM, and different media containing each metabolite of ECM were supplemented with 0.5% BSA to assess motility of thawed sperm after an incubation period of 6 hours. A positive effect on sperm motility was observed in all fresh and unconditioned media containing 1 mM pyruvate. Motion parameters were more efficiently maintained in all conditioned media than in unconditioned media. Our results showed, however, that pyruvate was almost completely oxidized or consumed by epididymal cells during preincubation of culture media. We conclude that motility of frozen-thawed bovine spermatozoa can be improved using a culture medium or a medium conditioned by epididymal cell cultures without carnitine but containing mainly pyruvate, inositol, glycerol, and lactate.

Optimization of the solid state fermentation process to obtain tempeh from hardened chickpeas (Cicer arietinum L.)

Solid state fermentation (SSF) represents a technological alternative for a great variety of cereals and legumes, or combination of them, to improve their nutritional quality and to obtain edible products with palatable sensorial characteristics. The objective of this work was to find the best conditions of fermentation temperature and time to obtain tempeh from hardened chickpeas (Cicer arietinum L.) applying SSF. Response surface methodology (RSM) was applied over three response variables (phytic acid, in vitro protein digestibility and available lysine) to find best conditions of fermentation to carry out the process. A central composite experimental design with two factors [X1 = temperature (31-36 degrees C) and X2 = time (48-72 h)] in five levels (2 factorials, 2 axial, I central) was used. Spores from Rhizopus stolonifer were suspended in distilled water (1 x 10(6) spores/mL) and used as starter. According to regression models, minimum and maximum levels of the response variables were 1.24-2.66 mg phytic acid/g of sample DM, 77.6-83.5% in vitro protein digestibility and 2.18-4.63 g available lysine/16 g N. The superposition of contour plots of each one of the response variables allowed researchers to find, graphically, the best conditions for the SSF process: 35.8 degrees C for 42.7 h.

Hard-to-cook phenomenon in chickpeas (Cicer arietinum L): effect of accelerated storage on quality

Storage, at high temperature (> or = 25 degrees C) and high relative humidity (> or = 65%), causes development of hard to cook (HTC) phenomenon in grain legumes. The objective of this work was to study the effect of storage simulating tropical conditions on chickpeas quality. The hardening of the Surutato 77, Mocorito 88, and Blanco Sinaloa 92 chickpea varieties was produced using adverse storage (32 +/- 1 degrees C, RH = 75%, 160 days) conditions. For all samples, the Hunter 'L' values decreased and deltaE values increased during storage, meaning a loss of color lightness and development of darkening. Accelerated storage caused a significant decrease in the water absorption capacities and cooking times of whole seeds, cotyledons and seed coats of all samples, being more pronounced in The Blanco Sinaloa 92 variety. Furthermore, storage produced significant decreases in the seed coat tannin content of the three materials; this parameter increased significantly in the cotyledon. In all samples, the levels of phytic acid decreased significantly with the seed hardness. Hardening of chickpea grains caused a decrease in the in vitro protein digestibilities of all varieties. These results suggest that both the cotyledon and seed coat play a significant role in the process of chickpea hardening. Blanco Sinaloa 92 and Mocorito 88 might be classified as varieties with high and low proneness, respectively, to the development of the HTC condition.

Response of PC-3 prostate cancer cells to combination therapy using irradiation with glucocorticoids or doxorubicin

OBJECTIVES

We evaluated the effects of irradiation, doxorubicin and dexamethasone on human PC-3 prostate cancer cells, investigating whether dexamethasone and doxorubicin can alter the irradiation cytotoxicity of PC-3 cells.

METHODS

We used the human PC-3 prostate cancer cells, analyzing cell growth with trypan blue exclusion, indices of the cell cycle with flow cytometry and apoptosis with flow cytometry and analysis of DNA fragmentation on simple agarose gel.

RESULTS

Doxorubicin (100 nM) arrested cell cycle at the G2/M phase, decreased cell growth and produced apoptosis of PC-3 cells in a time-dependent manner. Dexamethasone (100 nM) increased the distribution of PC-3 cells at G0/G1 phase in the cell cycle, exerting an inhibitory effect on the proliferation of PC-3 cells after 48 and 72 hr, but it did not produce apoptosis. Irradiation (4 Gy) initially arrested cells at the G2/M phase in the cell cycle (24 hr) which was gradually overcome and the PC-3 cells were shifted into G0/G1 phase or apoptosis after 48 and 72 hr. Irradiation decreased the PC-3 cell growth by 40-50% after 48 and 72 hr, respectively. Treatment with doxorubicin (100 nM) for 24, 48, and 72 hr after irradiation potentiated irradiation cytotoxicity of PC-3 cells. Dexamethasone treatment 24 hr before and 24, 48 and 72 hr after irradiation increased the number of surviving PC-3 cells and partially neutralized the irradiation effects on cell cycle.

CONCLUSION

Doxorubicin potentiated while dexamethasone partially reversed the irradiation cytotoxicity of PC-3 cells. These data may be of clinical importance for the treatment of hormone refractory prostate cancer.

Chemotherapy cytotoxicity of human MCF-7 and MDA-MB 231 breast cancer cells is altered by osteoblast-derived growth factors

One-third of women with breast cancer will develop bone metastases and eventually die from disease progression at these sites. Therefore, we analyzed the ability of human MG-63 osteoblast-like cells (MG-63 cells), MG-63 conditioned media (MG-63 CM), insulin-like growth factor I (IGF-I), and transforming growth factor beta 1 (TGF-beta1) to alter the effects of adriamycin on cell cycle and apoptosis of estrogen receptor negative (ER-) MDA-MB-231 and positive (ER+) MCF-7 breast cancer cells, using cell count, trypan blue exclusion, flow cytometry, detection of DNA fragmentation by simple agarose gel, and the terminal deoxynucleotidyl transferase (TdT)-mediated nick end-labeling method for apoptosis (TUNEL assay). Adriamycin arrested MCF-7 and MDA-MB-231 cells at G2/M phase in the cell cycle and inhibited cell growth. In addition, adriamycin arrested the MCF-7 cells at G1/G0 phase and induced apoptosis of MDA-MB-231 cells. Exogenous IGF-I partially neutralized the adriamycin cytotoxicity/cytostasis of cancer cells. MG-63 CM and TGF-beta1 partially neutralized the adriamycin cytotoxicity of MDA-MB-231 cells but enhanced adriamycin blockade of MCF-7 cells at G1/G0 phase. MG-63 osteoblast-like cells inhibited growth of MCF-7 cells while promoting growth and rescued MDA-MB-231 cells from adriamycin apoptosis in a collagen co-culture system. These data suggest that osteoblast-derived growth factors can alter the chemotherapy response of breast cancer cells. Conceivably, host tissue (bone)-tumor cell interactions can modify the clinical response to chemotherapy in patients with advanced breast cancer.

Osteoblast-derived growth factors enhance adriamycin-cytostasis of MCF-7 human breast cancer cells

Bone only metastasis in patients with estrogen receptor (ER) positive breast cancer reported to have favorable response to chemotherapy, favorable prognosis, and an "indolent" course. Therefore, we assessed the ability of MG-63 osteoblast-like human osteosarcoma cells (MG-63 cells) and MG-63 conditioned media (CM) to influence adriamycin-cytotoxicity of ER-positive MCF-7 human breast cancer cells. Estradiol (E2; 100 nM) increased the distribution at S and G2/M phases in the cell cycle and stimulated the growth of MCF-7 cells. Adriamycin (100 nM) inhibited the growth and arrested the MCF-7 cells supplemented with or without 100 nM of estradiol [(-E2) and (+E2) MCF-7 cultures] at G2/M phase in the cell cycle. In addition, adriamycin (100 nM) increased the distribution at G1/G0 phase in the cell cycle of (+E2) MCF-7 cultures. Adriamycin (100 nM and 10 microM) did not induce apoptosis of MCF-7 cells as assessed by flow cytometry and analysis of DNA fragmentation on simple agarose gel. Exogenous insulin-like growth factor I (IGF I) stimulated while transforming growth factor beta 1 (TGF beta 1) and MG-63 CM inhibited the growth of MCF-7 cells. Furthermore, MG-63 CM and TGF beta 1 enhanced while exogenous IGF I reversed adriamycin (100 nM)-cytostasis of MCF-7 cells. These data suggested that osteoblastic CM contained growth factors, such as TGF beta 1 capable of enhancing adriamycin-cytostasis, in vitro. Conceivably, these osteoblast-derived "enhancers" of chemotherapy-cytostasis can explain the favorable prognosis and "indolent" course of ER-positive breast cancer patients with bone only metastasis.