Oligogalacturonide application increases resistance to Fusarium head blight in durum wheat.

Fusariosis causes substantial yield losses in the wheat crop worldwide and compromises food safety because of the presence of toxins associated with the fungal disease. Among the current approaches to crop protection, the use of elicitors able to activate natural defense mechanisms in plants is a strategy gaining increasing attention. Several studies indicate that applications of plant cell-wall-derived elicitors, such as oligogalacturonides (OGs) derived from partial degradation of pectin, induce local and systemic resistance against plant pathogens. The aim of this study was to establish the efficacy of OGs in protecting durum wheat (Triticum turgidum subsp. durum), which is characterized by an extreme susceptibility to Fusarium graminearum. To evaluate the functionality of OGs, spikes and seedlings of cv. Svevo were inoculated with OGs, F. graminearum spores, and a co-treatment of both. Results demonstrated that OGs are active elicitors of wheat defenses, triggering typical immune marker genes and determining regulation of fungal genes. Moreover, bioassays on spikes and transcriptomic analyses on seedlings showed that OGs can regulate relevant physiological processes in Svevo with dose-dependent specificity. Thus, the OG sensing system plays an important role in fine tuning immune signaling pathways in durum wheat.

Impact of two Erwinia sp. on the response of diverse Pisum sativum genotypes under salt stress.

Currently, salinization is impacting more than 50% of arable land, posing a significant challenge to agriculture globally. Salt causes osmotic and ionic stress, determining cell dehydration, ion homeostasis, and metabolic process alteration, thus negatively influencing plant development. A promising sustainable approach to improve plant tolerance to salinity is the use of plant growth-promoting bacteria (PGPB). This work aimed to characterize two bacterial strains, that have been isolated from pea root nodules, initially called PG1 and PG2, and assess their impact on growth, physiological, biochemical, and molecular parameters in three pea genotypes (Merveille de Kelvedon, Lincoln, Meraviglia d'Italia) under salinity. Bacterial strains were molecularly identified, and characterized by in vitro assays to evaluate the plant growth promoting abilities. Both strains were identified as Erwinia sp., demonstrating in vitro biosynthesis of IAA, ACC deaminase activity, as well as the capacity to grow in presence of NaCl and PEG. Considering the inoculation of plants, pea biometric parameters were unaffected by the presence of the bacteria, independently by the considered genotype. Conversely, the three pea genotypes differed in the regulation of antioxidant genes coding for catalase (PsCAT) and superoxide dismutase (PsSOD). The highest proline levels (212.88 µmol g-1) were detected in salt-stressed Lincoln plants inoculated with PG1, along with the up-regulation of PsSOD and PsCAT. Conversely, PG2 inoculation resulted in the lowest proline levels that were observed in Lincoln and Meraviglia d'Italia (35.39 and 23.67 µmol g-1, respectively). Overall, this study highlights the potential of these two strains as beneficial plant growth-promoting bacteria in saline environments, showing that their inoculation modulates responses in pea plants, affecting antioxidant gene expression and proline accumulation. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-024-01419-8.

Inhibition of mTOR/S6K1/4E-BP1 Signaling by Nutraceutical SIRT1 Modulators.

The mTOR pathway plays a crucial role in many human diseases, mostly associated with an over hyperactivity of the mTOR signaling, which makes its inhibitors potentially effective therapeutics. Thus, it is important to consider not only the mTOR pathway, but also all those factors that play a key role in its regulation, such as SIRT1 and AMPK. We previously demonstrated the role of some nutraceutical SIRT1 modulators in AMPK and mTOR pathway, showing the presence of a synergistic effect. Now we take further our research by evaluating the effect of berberine, quercetin, tyrosol, and ferulic acid on the mTOR/S6K1/4E-BP1 signaling, along with the existence of any synergistic effect between the following associations: berberine + tyrosol, tyrosol + ferulic acid, ferulic acid + quercetin. Our results indicate the existence of an important relationship between the substances tested and the pathway of mTOR/S6K1/4E-BP1, a report corroborated by the bond of mTOR with SIRT1/AMPK pathways and by their reciprocal regulation.

Endothelial progenitor cell-derived extracellular vesicles protect from complement-mediated mesangial injury in experimental anti-Thy1.1 glomerulonephritis.

BACKGROUND: Endothelial progenitor cells (EPCs) are known to induce tissue repair by paracrine mechanisms including the release of growth factors and extracellular vesicles (EVs), nanoparticles able to carry proteins and genetic information to target cells. The aim of this study was to evaluate whether EVs derived from EPCs may protect from complement-mediated mesangial injury in experimental anti-Thy1.1 glomerulonephritis. METHODS: EVs were isolated by serial ultracentrifugation from supernatants of cultured human EPCs and characterized for their protein and RNA content. In vivo, EVs were injected i.v. in the experimental rat model of mesangiolytic anti-Thy1.1 glomerulonephritis evaluating renal function, proteinuria, complement activity and histological lesions. In vitro, the biological effects of EPC-derived EVs were studied in cultured rat mesangial cells incubated with anti-Thy1.1 antibody and rat or human serum as complement source. RESULTS: After i.v. injection in Thy1.1-treated rats, EVs localized within injured glomeruli and inhibited mesangial cell activation, leucocyte infiltration and apoptosis, decreased proteinuria, increased serum complement haemolytic activity (CH50) and ameliorated renal function. EV treatment decreased intraglomerular deposition of the membrane attack complex (MAC or C5b-9) and expression of smooth muscle cell actin and preserved the endothelial antigen RECA-1 and the podocyte marker synaptopodin. The protective effect of EVs was significantly reduced by pre-treatment with a high dose of RNase (1 U/mL), suggesting a key role for EV-carried RNAs in these mechanisms. Indeed, EPC-derived EVs contained different mRNAs coding for several anti-apoptotic molecules and for the complement inhibitors Factor H, CD55 and CD59 and the related proteins. The in vitro experiments aimed to investigate the mechanisms of EV protection indicated that EVs transferred to mesangial cell mRNAs coding for Factor H, CD55 and CD59 and inhibited anti-Thy1.1 antibody/complement-induced apoptosis and C5b-9/C3 mesangial cell deposition. CONCLUSIONS: EVs derived from EPCs exert a protective effect in Thy1.1 glomerulonephritis by inhibition of antibody- and complement-mediated injury of mesangial cells.

Diverse plant promoting bacterial species differentially improve tomato plant fitness under water stress.

Introduction: Food crops are increasingly susceptible to the challenging impacts of climate change, encompassing both abiotic and biotic stresses, that cause yield losses. Root-associated microorganisms, including plant growth-promoting bacteria (PGPB), can improve plant growth as well as plant tolerance to environmental stresses. The aims of this work were to characterize bacteria isolated from soil and roots of tomato plants grown in open field. Methods: Biochemical and molecular analyses were used to evaluate the PGP potential of the considered strains on tomato plants in controlled conditions, also assessing their effects under a water deficit condition. The isolated strains were classified by 16S gene sequencing and exhibited typical features of PGPB, such as the release of siderophores, the production of proteases, and phosphorous solubilization. Inoculating tomato plants with eleven selected strains led to the identification of potentially interesting strains that increased shoot height and dry weight. Three strains were then selected for the experiment under water deficit in controlled conditions. The tomato plants were monitored from biometric and physiological point of view, and the effect of inoculation at molecular level was verified with a targeted RT-qPCR based approach on genes that play a role under water deficit condition. Results: Results revealed the PGP potential of different bacterial isolates in tomato plants, both in well-watered and stressed conditions. The used integrated approach allowed to obtain a broader picture of the plant status, from biometric, eco-physiological and molecular point of view. Gene expression analysis showed a different regulation of genes involved in pathways related to abscisic acid, osmoprotectant compounds and heat shock proteins, depending on the treatments. Discussion: Overall, results showed significant changes in tomato plants due to the bacterial inoculation, also under water deficit, that hold promise for future field applications of these bacterial strains, suggesting that a synergistic and complementary interaction between diverse PGPB is an important point to be considered for their exploitation.

Resveratrol-poor red wines modulate SIRT1 in human renal cells.

The cardioprotective and anti-aging effects of red wine phenols, especially resveratrol (RSV), are well known. One of the most interesting biological properties of RSV and other naturally occurring phenols is the regulation of the expression and activity of SIRT1 (silent mating type information regulation 2 homolog). In view of the role of SIRT1 in acute and chronic renal diseases, we decided to study the effects of RSV-poor red wines on the expression of SIRT1 and HIF-2α (hypoxia-inducible factor 2α) to be compared with a nanomolar concentration of RSV or malvidin in proximal tubular cells of human kidneys (PTEC). Survival signaling systems activation (extracellular signal-regulated kinases, ERK and AMP-activated protein kinase, AMPK) was also investigated in PTEC incubated with wines. PTEC cells were incubated in the presence of RSV-poor wines diluted 1:1,000 for 30', 90', 120' and 24 h. Expression of SIRT1 and HIF-2α, and activation of ERK and AMPK were analyzed by Western Blot. The data obtained show that wine modulates the expression of anti-aging molecular systems even when RSV is present in very small amounts.

Diverse mycorrhizal maize inbred lines differentially modulate mycelial traits and the expression of plant and fungal phosphate transporters.

Food production is heavily dependent on soil phosphorus (P), a non-renewable mineral resource essential for plant growth and development. Alas, about 80% is unavailable for plant uptake. Arbuscular mycorrhizal fungi may promote soil P efficient use, although the mechanistic aspects are yet to be completely understood. In this study, plant and fungal variables involved in P acquisition were investigated in maize inbred lines, differing for mycorrhizal responsiveness and low-P tolerance, when inoculated with the symbiont Rhizoglomus irregulare (synonym Rhizophagus irregularis). The expression patterns of phosphate transporter (PT) genes in extraradical and intraradical mycelium (ERM/IRM) and in mycorrhizal and control maize roots were assessed, together with plant growth responses and ERM extent and structure. The diverse maize lines differed in plant and fungal accumulation patterns of PT transcripts, ERM phenotypic traits and plant performance. Mycorrhizal plants of the low-P tolerant maize line Mo17 displayed increased expression of roots and ERM PT genes, compared with the low-P susceptible line B73, which revealed larger ERM hyphal densities and interconnectedness. ERM structural traits showed significant correlations with plant/fungal expression levels of PT genes and mycorrhizal host benefit, suggesting that both structural and functional traits are differentially involved in the regulation of P foraging capacity in mycorrhizal networks.

Sex hormone receptors in vocal fold tissue: a theory about the influence of sex hormones in the larynx.

OBJECTIVE: The larynx is considered a secondary sexual organ. To demonstrate that sex hormones can directly influence laryngeal function, specific receptors in the vocal cord must be identified. MATERIALS AND METHODS: We searched for estrogen, progesterone and androgen receptors, using an immunohistochemical method, in normal human vocal cords (from 3 cadavers) and in samples of healthy vocal cords and of laryngeal carcinomas from 15 live subjects. Breast and prostate carcinoma were used as controls. RESULTS: In all the normal samples tested, the results were negative; there was only a nonspecific cytoplasmatic response in the subepithelial glands (false positives). In the neoplastic tissue, 2 samples had a weak nuclear focal positivity for estrogen and progesterone receptors; all 15 subjects studied were negative for androgen receptors. CONCLUSIONS: Since our data show that sex hormone receptors are absent in the vocal cords, other theories must be considered to explain the fact that hormones influence the quality of the voice. This study discusses the possibility that the changes of voice according to gender and throughout life might be linked with a different expression of some growth factors in the laryngeal tissue and that this expression might in turn be influenced by hormonal variations.

Diversity of a phosphate transporter gene among species and isolates of arbuscular mycorrhizal fungi.

Arbuscular mycorrhizal fungi (AMF) are a key group of beneficial obligate biotrophs, establishing a mutualistic symbiosis with the roots of most land plants. The molecular markers generally used for their characterization are mainly based on informative regions of nuclear rDNA (SSU-ITS-LSU), although protein-encoding genes have also been proposed. Within functional genes, those encoding for phosphate transporters (PT) are particularly important in AMF, given their primary ability to take up Pi from soil, and to differentially affect plant phosphate nutrition. In this work, we investigated the genetic diversity of PT1 gene sequences and sequences of the taxonomically relevant SSU-ITS-LSU region in two isolates of the species Funneliformis coronatus, three isolates of the species Funneliformis mosseae and two species of the genus Rhizoglomus, originated from geographically distant areas and cultured in vivo. Our results showed that partial PT1 sequences not only successfully differentiated AMF genera and species like ribosomal gene sequences but also highlighted intraspecific diversity among F. mosseae and F. coronatus isolates. The study of functional genes related to the uptake of key mineral nutrients for the assessment of AMF diversity represents a key step in the selection of efficient isolates to be used as inocula in sustainable agriculture.

In Vitro Alteration by Dentine and Protein of the Antimicrobial Activity of Two Endodontic Irrigants: HybenX® and Sodium Hypochlorite.

Irrigant solutions commonly used for the treatment of endodontic infections can be inhibited by both organic and inorganic substances. The aim of this study was to evaluate the in vitro antimicrobial activity of the novel irrigant HybenX® and 2.5% and 5% sodium hypochlorite against Enterococcus faecalis, in presence of dentine powder (DP) or bovine serum albumin 20% (BSA) as inhibitory agents. An E. faecalis American Type Culture Collection (ATCC) 29212 suspension was added to the irrigants (Hybenx® or NaOCl) and one or two different inhibitors (BSA and DP) either after one-hour pre-incubation at 35 ± 1 °C or not. The antimicrobial activity of HybenX® against E. faecalis was already proved at 15 min and was neither affected by BSA nor by DP or combinations thereof. NaOCl 2.5% showed an effective antimicrobial activity starting from 15 min and this activity was partially inhibited by BSA and BSA plus DP combination within one hour when pre-incubation occurred. NaOCl 5% showed antimicrobial activity within 15 min, which was inhibited within one hour only in the presence of both BSA and DP regardless of the pre-incubation period. HybenX® could represent a good alternative to common irrigants for the treatment of E. faecalis endodontic infections, showing a rapid antimicrobial activity not inhibited by organic and inorganic inhibitors.

In Vitro Antimicrobial Activity of the Decontaminant HybenX® Compared to Chlorhexidine and Sodium Hypochlorite against Common Bacterial and Yeast Pathogens.

The recent increase in infections mediated by drug-resistant bacterial and fungal pathogens underlines the urgent need for novel antimicrobial compounds. In this study, the antimicrobial activity (inhibitory and cidal) of HybenX®, a novel dessicating agent, in comparison with commonly used sodium hypochlorite and chlorhexidine, against a collection of bacterial and yeast strains representative of the most common human pathogenic species was evaluated. The minimal inhibitory, bactericidal, and fungicidal concentrations (MIC, MBC, and MFC, respectively) of the three different antimicrobial agents were evaluated by broth microdilution assays, followed by subculturing of suitable dilutions. HybenX® was active against 26 reference strains representative of staphylococci, enterococci, Enterobacterales, Gram-negative nonfermenters, and yeasts, although at higher concentrations than sodium hypochlorite and chlorhexidine. HybenX® MICs were 0.39% for bacteria (with MBCs ranging between 0.39% and 0.78%), and 0.1-0.78% for yeasts (with MFCs ranging between 0.78% and 1.6%). HybenX® exhibited potent inhibitory and cidal activity at low concentrations against several bacterial and yeast pathogens. These findings suggest that HybenX® could be of interest for the treatment of parodontal and endodontic infections and also for bacterial and fungal infections of other mucous membranes and skin as an alternative to sodium hypochlorite and chlorhexidine.

Plasma and serum brain-derived neurotrophic factor (BDNF) in depressed patients during 1 year of antidepressant treatments.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) has been hypothesized to be involved in the neurobiology of major depression. The aim of this study was to assess the possible relationships between depressive symptoms and serum and/or plasma BDNF levels during 1 year of antidepressant treatment. METHODS: Plasma and serum BDNF levels were assayed in 15 drug-free depressed patients and in 15 healthy control subjects at baseline and the 1st, 3rd, 6th and 12th month of antidepressant treatment. RESULTS: At baseline, patients' serum and plasma BDNF levels were significantly lower (p<.001 and p=.004, respectively) than those found in healthy control subjects. However, while from the 1st month of treatment patients' plasma BDNF levels did not differ significantly from those observed in healthy control subjects, serum BDNF levels in patients remained significantly lower at all times. LIMITATIONS: The main limitations of the current study are represented by the small sample size and the high discontinuation rate. CONCLUSIONS: Untreated depressed patients showed reduced baseline serum and plasma BDNF levels, as compared with control subjects. The clinical improvement paralleled the normalization of plasma BDNF after 1 month of treatment, while, at every assessment time, patients' serum BDNF levels were lower than those of control subjects. This would suggest that serum BDNF might represent a non-specific trait marker of depression.

An in vitro comparative study of the antioxidant activity and SIRT1 modulation of natural compounds.

Oxidative stress arises from an imbalance between the production of free radicals and antioxidant defences. Several studies have suggested that dietary antioxidants (such as polyphenols and berberine) may counteract oxidative stress through the involvement of the Sirtuin 1/Adenosine Monophosphate-Activated Protein Kinase (SIRT1/AMPK) pathway. The aim of this study was to evaluate the direct and specific antioxidant activity of some natural compounds, as well as their ability to modulate the expression of SIRT1 and the activation of AMPK. Quercetin, tyrosol, ferulic acid, catechin, berberine and curcumin were evaluated for their specific and direct antioxidant activity with TOSC assay. Their ability to modulate SIRT1 and AMPK was assessed by immunoblotting assay, while their cytotoxicity by CellTiter-Blue Cell Viability Assay. No statistically significant decrease (p > 0.05) in the number of viable cells was found upon challenging with the natural compounds. Quercetin exhibited the highest antioxidant activity against peroxyl radical and peroxinitrate derivates, while curcumin showed the best anti-hydroxyl activity with respect to the other compounds and, most importantly, respect to the reference antioxidants. Finally, all the tested compounds significantly increased the SIRT1 expression and the activation of AMPK. Our results clearly disclose the specific antioxidant activity of these natural compounds and their ability to increase SIRT1 expression and AMPK activation.

Dopamine D2 Receptors Dimers: How can we Pharmacologically Target Them?

BACKGROUND: Dopamine D2 and D3 receptors can form homo- and heterodimers and are important targets in Schizophrenia and Parkinson's. Recently, many efforts have been made to pharmacologically target these receptor complexes. This review focuses on various strategies to act specifically on dopamine receptor dimers, that are transiently formed. METHODS: Various binding and functional assays were reviewed to study the properties of bivalent ligands, particularly for the dualsteric compound SB269,652. The dimerization of D2 and D3 receptors were analyzed by using single particle tracking microscopy. RESULTS: The specific targeting of dopamine D2 and D3 dimers can be achieved with bifunctional ligands, composed of two pharmacophores binding the two orthosteric sites of the dimeric complex. If the target is a homodimer, then the ligand is homobivalent. Instead, if the target is a heterodimer, then the ligand is heterobivalent. However, there is some concern regarding pharmacokinetics and binding properties of such drugs. Recently, a new generation of bitopic compounds with dualsteric properties have been discovered that bind to the orthosteric and the allosteric sites in one monomeric receptor. Regarding dopamine D2 and D3 receptors, a new dualsteric molecule SB269,652 was shown to have selective negative allosteric properties across D2 and D3 homodimers, but it behaves as an orthosteric antagonist on receptor monomer. Targeting dimers is also complicated as they are transiently formed with varying monomer/dimer ratio. Furthermore, this ratio can be altered by administering an agonist or a bifunctional antagonist. CONCLUSION: Last 15 years have witnessed an explosive amount of work aimed at generating bifunctional compounds as a novel strategy to target GPCR homo- and heterodimers, including dopamine receptors. Their clinical use is far from trivial, but, at least, they have been used to validate the existence of receptor dimers in-vitro and in-vivo. The dualsteric compound SB269, 652, with its peculiar pharmacological profile, may offer therapeutic advantages and a better tolerability in comparison with pure antagonists at D2 and D3 receptors and pave the way for a new generation of antipsychotic drugs.

Synthesis, biological evaluation and molecular modeling of novel azaspiro dihydrotriazines as influenza virus inhibitors targeting the host factor dihydrofolate reductase (DHFR).

Recently we identified cycloguanil-like dihydrotriazine derivatives, which provided host-factor directed antiviral activity against influenza viruses and respiratory syncytial virus (RSV), by targeting the human dihydrofolate reductase (hDHFR) enzyme. In this context we deemed interesting to further investigate the structure activity relationship (SAR) of our first series of cycloguanil-like dihydrotriazines, designing two novel azaspiro dihydrotriazine scaffolds. The present study allowed the exploration of the potential chemical space, around these new scaffolds, that are well tolerated for maintaining the antiviral effect by means of interaction with the hDHFR enzyme. The new derivatives confirmed their inhibitory profile against influenza viruses, especially type B. In particular, the two best compounds shared potent antiviral activity (4: EC50 = 0.29 µM; 6: EC50 = 0.19 µM), which was comparable to that of zanamivir (EC50 = 0.14 µM), and better than that of ribavirin (EC50 = 3.2 µM). In addition, these two compounds proved to be also effective against RSV (4: EC50 = 0.40 µM, SI ≥ 250; 6: EC50 = 1.8 µM, SI ≥ 56), surpassing the potency and selectivity index (SI) of ribavirin (EC50 = 5.8 µM, SI > 43). By a perspective of these results, the above adequately substituted azaspiro dihydrotriazines may represent valuable hit compounds worthy of further structural optimization to develop improved host DHFR-directed antiviral agents.

Simvastatin and fluvastatin reduce interleukin-6 and interleukin-8 lipopolysaccharide (LPS) stimulated production by isolated human monocytes from chronic kidney disease patients.

BACKGROUND: Statins reduce lipid levels, inflammation and cardiovascular events in patients with coronary artery disease; CKD patients show increased risk of cardiovascular and increased plasma levels of IL-6 and IL-8. AIM: To evaluate the in vitro effect of simvastatin (S) or fluvastatin (F) on the lipopolysaccharide (LPS) stimulated secretion of IL-6 and IL-8 from monocytes of chronic kidney disease patients (CKD) in K-DOQI stages 3-5. METHODS AND SUBJECTS: Monocytes enriched peripheral blood (PBMC) from 28 CKD (15 in K-DOQI stages 3-4, Group I, and 13 in K-DOQI stage 5 on hemodialysis, Group II) and 10 healthy subjects (HS), were isolated by Ficoll-gradient centrifugation. Cells were incubated with LPS 100 ng/ml or with LPS plus increasing doses of statins (from 10(-6) to 10(-8) M ) for 24 h. Surnatant IL-6 and IL-8 concentrations were determined by EIA. RESULTS: Basally the mean concentration of IL-6 and IL-8 was higher in patients than in HS and in Group II than in Group I (IL6: HS 285 +/- 77 pg/ml, Group I 365 +/- 178 pg/ml, Group II 520 +/- 139 pg/ml- IL8 HS 180 +/- 75 pg/ml, Group I 1722 +/- 582 pg/ml, Group II 4400 +/- 1935 pg/ml). After addition of LPS the mean concentration of IL-6 and IL-8 increased in all groups (IL6: HS 1740 +/- 178 pg/ml, Group I 3754 +/- 672 pg/ml, Group II 4800 +/- 967 pg/ml; IL8: HS 450+/-132 pg/ml, Group I 9700+/-2837 pg/ml, Group II 11608 +/- 2316 pg/ml). After the addition of LPS plus increasing doses of S or F from 10(-10) to 10(-6) M, a significantly lower cytokine concentration compared to the data after LPS alone was observed (IL6: HS 45%, Group I 75%, Group II 50%; IL8: HS 100%, Group I 65%, Group II 35%). CONCLUSIONS: These data confirm that cytokine release is increased in CKD patients and that is highest in the most severe patients. Furthermore they suggest that fluvastatin or simvastatin can be used in order to reduce the high cardiovascular risk.

Role of nutraceutical SIRT1 modulators in AMPK and mTOR pathway: Evidence of a synergistic effect.

OBJECTIVE: The aim of this study was to evaluate the effect of different natural substances on SIRT1 expression and on AMPK and mTOR phosphorylation. Moreover, we investigated the presence of a synergistic effect between the substances. METHODS: Human cervical carcinoma cells were seeded in 12-well plates, then incubated with the nine tested substances (resveratrol, quercetin, berberine, catechin, tyrosol, ferulic acid, niclosamide, curcumin, and malvidin) at different concentrations and left in incubation for 3, 6, and 24 h. The targeting proteins' expression and phosphorylation were evaluated by immunoblotting, and cytotoxicity tests were performed by CellTiter-Blue Cell Viability Assay. RESULTS: No statistically significant decrease (P > 0.05) in the number of viable cells was found. The expression of SIRT1 was significantly increased in all experimental groups compared with the control group (P < 0.001). Instead, the simultaneous administration involved a significant and synergistic increase in the expression of SIRT1 for some but not all of the tested compounds. Finally, the individual administration of berberine, quercetin, ferulic acid, and tyrosol resulted in a statistically significant increase in AMPK activation and mTOR inhibition, whereas their associated administration did not reveal a synergistic effect. CONCLUSIONS: Our results provide evidence that all compounds have the potential to stimulate SIRT1 and sustain the stimulating action of resveratrol on SIRT1, already widely reported in the literature. In this regard, we confirm the interaction of these substances also with the pathway of AMPK and mTOR, in support of the studies that highlight the importance of SIRT1/AMPK and mTOR pathway in many diseases.

Early cytotoxic effects of ochratoxin A in rat liver: a morphological, biochemical and molecular study.

We characterized the overall early effect of chronic ochratoxin A (OTA) treatment on rat liver, analyzing different aspects related to: (i) fibrosis, by measuring collagen content and turnover, and alpha-smooth muscle actin (alphaSMA); (ii) oxidative stress and stress response, by analyzing protein carbonylation, superoxide dismutase (SOD) and heat shock protein (HSP70) gene expression; (iii) the possible tumor promoter effect, evaluating cadherin and connexin (CX) mRNA levels. Light microscopy analysis showed no histological differences in OTA-treated and control (CT) rats. Collagen content, determined by computer analysis of Sirius red-stained liver sections, was similar in both groups. In liver homogenates COL-I, COL-III, TIMP-1 and TGF-beta1 mRNA levels and alphaSMA were unaffected by OTA. Matrix metalloproteinase (MMP)-1, MMP-2 and MMP-9 protein levels were also similar in the two groups. Protein carbonylation, a marker of severe oxidative stress, was not evident in the homogenates of OTA-treated livers; superoxide dismutase (SOD) mRNA tended to be lower and HSP70 was strongly down-regulated. OTA reduced E-cadherin and DSC-2 transcription, and down-regulated liver CX26, CX32 and CX43. In conclusion, these in vivo results show that OTA-induced liver injury involves a reduction in the ability to counterbalance oxidative stress, maybe leading to altered gap junction intercellular communication and loss of cell adhesion and polarity. This suggests that mild oxidative damage might be a key factor, in combination with other cytotoxic effects, in triggering the promotion of liver tumors after exposure to OTA.

Protective effect of L-propionylcarnitine in chronic cyclosporine-a induced nephrotoxicity.

Cyclosporine (CyA) is an immunosuppressive agent used after solid organ transplantation, but its clinical use is limited by side effects, the most important of which is nephrotoxicity. In a previous work we demonstrated that L-propionylcarnitine (L-PC), a propionyl ester of L-carnitine, is able to prevent CyA-induced acute nephrotoxicity reducing lipid peroxidation in the isolated and perfused rat kidney. CyA administration was associated with a dose dependent increase in renovascular resistance prevented by a pretreatment with L-PC. The aim of the present study was to confirm L-PC protective effect, previously described in vitro, in an in vivo rat model. Chronic nephrotoxicity study was carried out for 28 days. L-PC was administered (i.p. 25 mg/kg b.w.) since the first day, while CyA treatment was performed for the last 21 days (by oral administration 25 mg/kg b.w.). We demonstrate that L-PC was able to significantly lower blood pressure in CyA treated animals and to prevent CyA induced decrease in creatinine clearance. Moreover renal tissue analysis revealed that L-PC was able to reduce lipid hydroperoxide content and morphological abnormalities associated to chronic CyA administration. In conclusion our study demonstrated for the first time in vivo that L-PC protects against functional and tissue damage associated to chronic CyA administration.