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Recently, green microalgae have gained importance due to their nutritional and bioactive compounds, which makes them some of the most promising and innovative functional foods. The aim of this study was to evaluate the chemical profile and the in vitro antioxidant, antimicrobial and antimutagenic activity of an aqueous extract of the green microalga Ettlia pseudoalveolaris, obtained from the freshwater lakes of the Ecuadorian Highlands. Human microvascular endothelial cells (HMEC-1) were used to determine the ability of the microalga to reduce the endothelial damage caused by hydrogen peroxide-induced oxidative stress. Furthermore, the eukaryotic system Saccharomyces cerevisiae was used to evaluate the possible cytotoxic, mutagenic and antimutagenic effect of E. pseudoalveolaris. The extract showed a notable antioxidant capacity and a moderate antibacterial activity mostly due to the high content in polyphenolic compounds. It is likely that the antioxidant compounds present in the extract were also responsible for the observed reduction in endothelial damage of HMEC-1 cells. An antimutagenic effect through a direct antioxidant mechanism was also found. Based on the results of in vitro assays, E. pseudoalveolaris proved to be a good source of bioactive compounds and antioxidant, antibacterial and antimutagenic capacities making it a potential functional food.

BACKGROUND AND AIM: Glyphosate (G) is set for re-approval in the European Union in late 2022 and the full risk posed by glyphosate-based herbicides (GBHs) is still unclear.The Ramazzini Institute (...

Herein we characterized the bioactive metabolites of the aqueous extract of Kavolì®, a commercial product composed of a mixture of Brassica oleracea leaves, and assessed its potential ameliorating effects in a rat model of non-alcoholic fatty liver disease (NAFLD). Kavolì® extract showed high levels of bioactive compounds and strong in vitro antioxidant activities. Chlorogenic and neochlorogenic acids were identified as the most representative polyphenols. The administration of brassica extract to steatotic rats significantly ameliorated the levels of blood lipids and transaminases, and lipid content and inflammatory markers in liver. Oxidative stress parameters were significantly improved in both liver and brain of steatotic rats. Moreover, plasma and feces levels of short chain fatty acids (SCFAs) were bring back close to control values by Kavolì® treatment, in spite of high fat diet/streptozotocin (HFD/STZ)-induced alterations. The efficacy of Kavolì® in treating hypercholesterolemia, reducing the level of inflammation and cardiovascular disease biomarkers, steatosis and oxidative stress parameters, as well as the ability in modulating SCFAs levels is probably related to the bioactive compounds of the water extract administered to the rat model of NAFLD. In particular, the ameliorating effects are largely attributable to the high content in polyphenols observed in our study.

A large number of basic researches and observational studies suggested the cancer preventive activity of vitamin E, but large-scale human intervention trials have yielded disappointing results and actually showed a higher incidence of prostate cancer although the mechanisms underlying the increased risk remain largely unknown. Here we show through in vitro and in vivo studies that vitamin E produces a marked inductive effect on carcinogen-bioactivating enzymes and a pro-oxidant status promoting both DNA damage and cell transformation frequency. First, we found that vitamin E in the human prostate epithelial RWPE-1 cell line has the remarkable ability to upregulate the expression of various phase-I activating cytochrome P450 (CYP) enzymes, including activators of polycyclic aromatic hydrocarbons (PAHs), giving rise to supraphysiological levels of reactive oxygen species. Furthermore, our rat model confirmed that vitamin E in the prostate has a powerful booster effect on CYP enzymes associated with the generation of oxidative stress, thereby favoring lipid-derived electrophile spread that covalently modifies proteins. We show that vitamin E not only causes DNA damage but also promotes cell transformation frequency induced by the PAH-prototype benzo[a]pyrene. Our findings might explain why dietary supplementation with vitamin E increases the prostate cancer risk among healthy men.

Background In 2011, IARC classified radiofrequency radiation (RFR) as possible human carcinogen (Group 2B). According to IARC, animals studies, as well as epidemiological ones, showed limited evidence of carcinogenicity. In 2016, the NTP published the first results of its long-term bioassays on near field RFR, reporting increased incidence of malignant glial tumors of the brain and heart Schwannoma in rats exposed to GSM – and CDMA – modulated cell phone RFR. The tumors observed in the NTP study are of the type similar to the ones observed in some epidemiological studies of cell phone users. Objectives The Ramazzini Institute (RI) performed a life-span carcinogenic study on Sprague-Dawley rats to evaluate the carcinogenic effects of RFR in the situation of far field, reproducing the environmental exposure to RFR generated by 1.8 GHz GSM antenna of the radio base stations of mobile phone. This is the largest long-term study ever performed in rats on the health effects of RFR, including 2448 animals. In this article, we reported the final results regarding brain and heart tumors. Methods Male and female Sprague-Dawley rats were exposed from prenatal life until natural death to a 1.8 GHz GSM far field of 0, 5, 25, 50 V/m with a whole-body exposure for 19 h/day. Results A statistically significant increase in the incidence of heart Schwannomas was observed in treated male rats at the highest dose (50 V/m). Furthermore, an increase in the incidence of heart Schwann cells hyperplasia was observed in treated male and female rats at the highest dose (50 V/m), although this was not statistically significant. An increase in the incidence of malignant glial tumors was observed in treated female rats at the highest dose (50 V/m), although not statistically significant. Conclusions The RI findings on far field exposure to RFR are consistent with and reinforce the results of the NTP study on near field exposure, as both reported an increase in the incidence of tumors of the brain and heart in RFR-exposed Sprague-Dawley rats. These tumors are of the same histotype of those observed in some epidemiological studies on cell phone users. These experimental studies provide sufficient evidence to call for the re-evaluation of IARC conclusions regarding the carcinogenic potential of RFR in humans.

Polyphenol-rich foods could have a pivotal function in the prevention of oxidative stress-based pathologies and antibacterial action. The purpose of this study was to investigate the in vitro antimicrobial activity, as well as the in vitro and In Vivo antioxidant capacities of wild Prunus spinosa L. fruit (PSF) from the southeast regions of Italy. The total phenolic content (TPC) was quantified, and the single polyphenols were analyzed by HPLC-DAD, showing high rutin and 4-hydroxybenzoic acid levels, followed by gallic and trans-sinapic acids. PSF extract demonstrated antimicrobial activity against some potentially pathogenic Gram-negative and Gram-positive bacteria. Besides, we investigated the cellular antioxidant activity (CAA) and the hemolysis inhibition of PSF extract on human erythrocytes, evidencing both a good antioxidant power and a marked hemolysis inhibition. Furthermore, an In Vivo experiment with oxidative stress-induced rats treated with a high-fat diet (HFD) and a low dose of streptozotocin (STZ) demonstrated that PSF has a dose-dependent antioxidant capacity both in liver and in brain. In conclusion, the wild Italian Prunus spinosa L. fruit could be considered a potentially useful material for both nutraceutical and food industries because of its antioxidant and antimicrobial effects.

The proliferation of cellular antennas and other radiofrequency radiation (RFR) generating devices of the last decades has led to more and more concerns about the potential health effects from RFR exposure. Since the 2011 classification as a possible carcinogen by the International Agency for Research on Cancer (IARC), more experimental studies have been published that support a causal association between RFR exposure and health hazards. As regard cancer risk, two long-term experimental studies have been recently published by the US National Toxicology Program (NTP) and the Italian Ramazzini Institute (RI). Despite important experimental differences, both studies found statistically significant increases in the development of the same type of very rare glial malignant tumors. In addition to carcinogenicity, reproductive organs might be particularly exposed, as well as sensitive to RFR. In this work, we reviewed the currently available evidence from in vivo studies on carcinogenicity and reproductive toxicity studies in order to summarize the contribution of experimental research to the prevention of the adverse effects of RFR on human health.

The cancer hazard associated with exposure to cell phone radiofrequency radiation (RFR) was examined using lifetime exposure in Sprague-Dawley (SD) rats at the Ramazzini Institute (RI), Italy. There were increased incidences of gliomas in the brain and schwannomas in the heart. In order to understand the translational relevance of these rat tumors for human disease, we examined the top 23 orthologous cancer genes mutated in human gliomas using a custom built a next-generation sequencing gene panel for rats based on Illumina’s TruSeq Custom Amplicon Technology. SD rat tissues (gliomas =15; cardiac schwannomas=9, interim (1 year) sacrificed non-tumor brain tissues from RFR exposed rats =30, control brain and heart control tissues from lifetime exposure=10 each, and age-matched control brain tissues from interim sacrificed rats=10) from the RI-RFR cancer bioassay were examined in this study. The deepSNV R-package with various filtering criteria and the read depth of >1000x were used to identify single-nucleotide variants (SNVs) in the rat gliomas and schwannomas. At 5% allelic frequency, there were an average of 43 SNVs per rat glioma and point mutations were detected in 9 genes (Arid1a, Cic, Tert promoter, Tp53, Atrx, Nf1, Pdgfra, Pi3kr1, and Setd2) in at least 3 or more rat gliomas based on population frequency. Five genes (Nf1, Tert promoter, Setd2, Arid1a, and Pdgfra) harbored SNVs in interim sacrificed brain tissues that were also present in RFR-exposed gliomas from lifetime exposure. Interestingly, no mutations were detected in hotspot regions of Idh1, Idh2, Egfr or Braf. In contrast to most human gliomas which harbor mutations in IDH1 and IDH2 genes, the rat gliomas seem to be Idh1 wild type with mutations in the other glioma-related genes. Primary cardiac tumors are extremely rare in humans. With this targeted NGS panel (at allelic frequency of 2.5%), there were an average of 146 SNVs per rat cardiac schwannoma and unique point mutations were detected in Cic, Egfr, Arid1a, Nf1, Setd2, Cdkn2a, Erbb2, Atrx, Pdgfra, and Notch1 in 3 or more cardiac schwannomas. A subset of the SNVs (Arid1a, Tp53, and Nf1) in rat gliomas was confirmed in human gliomas in the COSMIC database supporting the translational relevance of the rat gliomas for human disease. In addition, several SNVs from rat gliomas and cardiac schwannomas were found in various human cancers including carcinomas, hematopoietic neoplasms, melanomas and neuroendocrine tumors. In conclusion, the rat gliomas appear to share genetic alterations with a subtype of IDH1 wildtype human gliomas and rat primary cardiac schwannomas also harbor mutations in some of the queried cancer genes. Citation Format: Ramesh C. Kovi, Andrea Vornoli, Ashley Brooks, Thai Vu T. Ton, Miaofei Xu, Eva Tibaldi, Federica Gnudi, Jian-Liang Li, Robert C. Sills, John R. Bucher, Fiorella Belpoggi, Arun R. Pandiri. Genetic profiling of rat gliomas and cardiac schwannomas from cell phone radiofrequency radiation exposure using a targeted next-generation sequencing gene panel [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PO-084.

Electronic cigarettes (e-cigs) are devices designed to deliver nicotine in a vaping solution rather than smoke and without tobacco combustion. Perceived as a safer alternative to conventional cigarettes, e-cigs are aggressively marketed as lifestyle-choice consumables, thanks to few restrictions and a lack of regulatory guidelines. E-cigs have also gained popularity among never-smokers and teenagers, becoming an emergent public health issue. Despite the burgeoning worldwide consumption of e-cigs, their safety remains largely unproven and it is unknown whether these devices cause in vivo toxicological effects that could contribute to cancer. Here we demonstrate the co-mutagenic and cancer-initiating effects of e-cig vapour in a rat lung model. We found that e-cigs have a powerful booster effect on phase-I carcinogen-bioactivating enzymes, including activators of polycyclic aromatic hydrocarbons (PAHs), and increase oxygen free radical production and DNA oxidation to 8-hydroxy-2′-deoxyguanosine. Furthermore, we found that e-cigs damage DNA not only at chromosomal level in peripheral blood, such as strand breaks in leucocytes and micronuclei formation in reticulocytes, but also at gene level such as point mutations in urine. Our results demonstrate that exposure to e-cigs could endanger human health, particularly among younger more vulnerable consumers.

Polyphenol-rich foods could have a pivotal function in the prevention of oxidative stress-based pathologies and antibacterial action. The purpose of this study was to investigate the in vitro antimicrobial activity, as well as the in vitro and In Vivo antioxidant capacities of wild Prunus spinosa L. fruit (PSF) from the southeast regions of Italy. The total phenolic content (TPC) was quantified, and the single polyphenols were analyzed by HPLC-DAD, showing high rutin and 4-hydroxybenzoic acid levels, followed by gallic and trans-sinapic acids. PSF extract demonstrated antimicrobial activity against some potentially pathogenic Gram-negative and Gram-positive bacteria. Besides, we investigated the cellular antioxidant activity (CAA) and the hemolysis inhibition of PSF extract on human erythrocytes, evidencing both a good antioxidant power and a marked hemolysis inhibition. Furthermore, an In Vivo experiment with oxidative stress-induced rats treated with a high-fat diet (HFD) and a low dose of streptozotocin (STZ) demonstrated that PSF has a dose-dependent antioxidant capacity both in liver and in brain. In conclusion, the wild Italian Prunus spinosa L. fruit could be considered a potentially useful material for both nutraceutical and food industries because of its antioxidant and antimicrobial effects.

Background Glyphosate-based herbicides (GBHs) are broad-spectrum herbicides that act on the shikimate pathway in bacteria, fungi, and plants. The possible effects of GBHs on human health are the subject of an intense public debate for both its potential carcinogenic and non-carcinogenic effects, including its effects on microbiome. The present pilot study examines whether exposure to GBHs at doses of glyphosate considered to be “safe” (the US Acceptable Daily Intake - ADI - of 1.75 mg/kg bw/day), starting from in utero, may modify the composition of gut microbiome in Sprague Dawley (SD) rats. Methods Glyphosate alone and Roundup, a commercial brand of GBHs, were administered in drinking water at doses comparable to the US glyphosate ADI (1.75 mg/kg bw/day) to F0 dams starting from the gestational day (GD) 6 up to postnatal day (PND) 125. Animal feces were collected at multiple time points from both F0 dams and F1 pups. The gut microbiota of 433 fecal samples were profiled at V3-V4 region of 16S ribosomal RNA gene and further taxonomically assigned and assessed for diversity analysis. We tested the effect of exposure on overall microbiome diversity using PERMANOVA and on individual taxa by LEfSe analysis. Results Microbiome profiling revealed that low-dose exposure to Roundup and glyphosate resulted in significant and distinctive changes in overall bacterial composition in F1 pups only. Specifically, at PND31, corresponding to pre-pubertal age in humans, relative abundance for Bacteriodetes (Prevotella) was increased while the Firmicutes (Lactobacillus) was reduced in both Roundup and glyphosate exposed F1 pups compared to controls. Conclusions This study provides initial evidence that exposures to commonly used GBHs, at doses considered safe, are capable of modifying the gut microbiota in early development, particularly before the onset of puberty. These findings warrant future studies on potential health effects of GBHs in early development such as childhood. Electronic supplementary material The online version of this article (10.1186/s12940-018-0394-x) contains supplementary material, which is available to authorized users.

Aims A large meta-analysis of randomized clinical trials has seriously questioned chemoprevention based on vitamins including vitamin E (VE), and an increased risk for cancer among long-term users was actually seen. However, the mechanism underlying these findings still remain unknown. To clarify the mechanism, in an in vivo model we studied the putative disruption of redox homeostasis and the perturbation of carcinogen metabolizing enzymes determined by VE. Main methods Male Sprague–Dawley rats were treated ip with either 100 or 200 mg/kg b.w. daily for 7 or 14 consecutive days. Controls received vehicle only. Cytochrome P450 (CYP) content, CYP-reductase, CYP-linked monooxygenases, as well as phase-II and the antioxidant enzymes catalase and NAD(P)H:quinone reductase were investigated in both liver and kidney. Free radical species in tissue subcellular preparations were measured by electronic paramagnetic resonance (EPR) spectroscopy coupled to a radical probe technique. Key findings No substantial changes of hepatic xenobiotic metabolism enzymes were determined by VE. Conversely, a powerful booster effect of various renal phase-I carcinogen bioactivating enzymes at both dosages and observational times was recorded. While no relevant changes of post-oxidative phase-II reactions were found in the liver, a significant inactivating effect was caused by VE in renal tissues. Antioxidant enzymes were found mainly downregulated by the treatment. In the kidney, a marked free radical over-generation linked to CYP induction was observed. Significance This study proved that VE acts as a co-carcinogen and pro-oxidant agent. Such epigenetic mechanisms may contribute to explain the harmful outcomes observed in humans.

Background Up to now, experimental studies on rodents have failed to provide definitive confirmation of the carcinogenicity of extremely low frequency electromagnetic fields (ELFEMF). Two recent studies performed in our laboratory on Sprague-Dawley rats reported a statistically significant increase in malignant tumors of different sites (mammary gland, C-cells carcinoma, hemolymphoreticular neoplasia, and malignant heart Schwannoma) when ELFEMF exposure was associated with exposure to formaldehyde (50 mg/l) or acute low dose of γ-radiation (0.1 Gy) (Soffritti et al., 2016a) (Soffritti et al., 2016b). The same doses of known carcinogenic agents (50 mg/l formaldehyde, or acute 0.1 Gy γ-radiation), when administered alone, previously failed to induce any statistically significant increase in the incidence of total and specific malignant tumors in rats of the same colony. Objectives A lifespan whole-body exposure study was conducted to evaluate the possible carcinogenic effects of ELFEMF exposure administered alone to Sprague-Dawley rats, as part of the integrated project of the Ramazzini Institute (RI) for studying the effects on health of ELFEMF alone or in combination with other known carcinogens. Methods Male and female Sprague-Dawley rats were exposed 19 h/day to continuous sinusoidal-50 Hz magnetic fields (S-50 Hz MF) at flux densities of 0 (control group), 2, 20, 100 or 1000µT, and to intermittent (30 min on/30 min off) S-50 Hz MF at 1000 µT, from prenatal life until natural death. Results Survival and body weight trends in all groups of rats exposed to ELFEMF were comparable to those found in sex-matched controls. The incidence and number of malignant and benign tumors was similar in all groups. Magnetic field exposure did not significantly increase the incidence of neoplasias in any organ, including those sites that have been identified as possible targets in epidemiological studies (leukemia, breast cancer, and brain cancer). Conclusions Life-span exposures to continuous and intermittent sinusoidal-50 Hz ELFEMFs, when administered alone, did not represent a significant risk factor for neoplastic development in our experimental rat model. In light of our previous results on the carcinogenic effects of ELFEMF in combination with formaldehyde and γ-radiation, further experiments are necessary to elucidate the possible role of ELFEMF as cancer enhancer in presence of other chemical and physical carcinogens.

Herein we have characterized CYPs and antioxidant enzymes in a new steatotic rat model induced with a high fat diet (HFD) combined with a low dose of streptozotocin (STZ). This model was recently put forward in order to better replicate the NAFLD human pathology. HFD/STZ rats developed hyperglycemia, hypercholesterolemia and overt steatosis. The treatment also caused liver damage, but not lipid peroxidation, suggesting this damage was due to hepatic fat deposition and excess formation of toxic free fatty acids, rather than to oxidative stress. In the HFD/STZ group, a significant rise in total CYP content was found, in conjunction with increased activity and protein levels of CYP2E1 and CYP4A, the latter also up-regulated at the transcriptional level. A significant decrease of CYP2C11 was observed at the transcriptional and protein level, whereas CYP3A2 did not change in response to HFD/STZ treatment. In our experimental conditions, the activity of the HO-1 and NQO1 enzymes, whose genes are regulated by Nrf2, were not affected, and nor were the antioxidant enzymes SOD and CAT, confirming the lack of oxidative stress. Our HFD/STZ treatment, which established overt steatosis and changes in CYPs expression, but not oxidative stress, likely reflects an early stage of NAFLD.

Nella presente tesi, abbiamo caratterizzato un modello di ratto trattato con dieta iperlipidica e streptozotocina (D), utilizzato per valutare i potenziali effetti anti-steatotici di una miscela contenente 5 estratti vegetali (caigua, soia, erba medica, carciofo e riso rosso fermentato) somministrata a due differenti dosaggi (0,3 [A] e 1 mg/Kg [B]) e confrontata con il controllo positivo eugenolo (E) ed il veicolo di somministrazione latte di soia (M). I valori concernenti colesterolo, LDL, glucosio, ALT ed il contenuto di lipidi nel tessuto epatico sono risultati aumentati in D, A ed M, rispetto ai CTR, e ripristinati significativamente in B ed E. Le attività marcatrici del CYP2E1 (p-nitrofenolo idrossilasi ed anilina-idrossilasi) e le analisi di Western blotting per le proteine CYP2E1 e CYP4A hanno evidenziato una significativa induzione su D, A ed M ed un parziale ripristino dei valori di controllo in B. Dal dosaggio del GSH e della carbonilazione delle proteine è stata evidenziata la presenza di stress ossidativo nei ratti iperlipidici, significativamente ridotta nel B. La presenza del colesterolo nella dieta iperlipidica è stata determinante per la significativa riduzione dei geni HMGCR ed LDLr. Dall’analisi di geni coinvolti nell’infiammazione e nello stress mitocondriale si è evidenziato un significativo aumento nei gruppi D, A e M rispetto al CTR, mentre una significativa riduzione si è osservata in B ed E. Per estendere la caratterizzazione del ratto HFD/STZ, in un nuovo esperimento abbiamo analizzato geni chiave del metabolismo del colesterolo e del trasporto degli acidi biliari. Abbiamo osservato un’induzione dei geni responsabili della formazione dell’acido colico CYP7A1 e CYP8B1, ma non di quelli dell’acido chenodeossicolico CYP27A1 e CYP7B1. Inoltre è emersa una diminuita espressione di SHP (gene chiave per l’inibizione feedback del CYP7A1 e del CYP8B1) e dei geni responsabili del trasporto degli acidi biliari, del colesterolo, e della fosfatidilcolina., In this thesis, we characterized a rat model treated with a high fat diet and low dose of streptozotocin (HFD/STZ, D), to evaluate the anti-steatotic effects of a 5 plant extracts mixture (caigua, soybean, alfalfa, artichoke and fermented red rice) administered at two different doses (0.3 [A] and 1 mg/kg [B]) and compared to the positive control eugenol (E) and the vehicle soy milk (M) administration. Cholesterol, LDL, glucose and ALT blood parameters values and liver lipids content were increased in D, A and M, with the respect to CTR, and significantly recovered in B and E. CYP2E1 specific activities (p-nitrophenol hydroxylase and aniline hydroxylase) and Western blot analysis for CYP2E1 and CYP4A proteins were induced in D, A and M, and partially restored in B. GSH and protein carbonylation analysis highlighted, compared to CTR, the presence of oxidative stress in HFD/STZ rats, which was significantly reduced in B. The analysis of genes involved in inflammation (IL6, TNFα) and mitochondrial stress revealed a significant increase in A, D, M groups, but not in E and B. The presence of 2% of cholesterol in the high fat diet determined a significant reduction of HMGCR and LDLr transcripts. To extend the characterization of our steatotic rat model, we analyzed key genes of cholesterol metabolism and bile acids transporters in a new experiment. It was observed an induction of CYP7A1 and CYP8B1 genes responsible for the formation of cholic acid (CA), but not of CYP27A1 and CYP7B1, which lead to chenodeoxycholic acid (CDCA). In addition, we observed a decreased expression of FXR-regulated SHP (the key gene for the feedback CYP7A1 and CYP8B1 inhibition) and of the genes responsible for the transport of bile acids (NTCP, MRP2/4, OATP1A1, OATP1B2, BSEP), cholesterol (ABCG5), and phosphatidylcholine (MDR3).

Aims: The aim of the study was to evaluate lipid, cholesterol and glucose metabolism in a novel rat model of non-alcoholic fatty liver disease (NAFLD). Main methods: Rats (Wistar) were fed high fat/cholesterol diet (HFD) and a single low dose (35 mg/kg) of streptozotocin (STZ). Collagen and glycogen content, oxidative stress and glucokinase activity were measured using biochemical assays. Other metabolic pathways were assessed by qRT-PCR. Key findings: HFD/STZ treated rats, compared to control ones, showed an increase in expression of biomarkers of inflammation (TNFα, IL6), fibrosis (TGFβ), mitochondrial stress (UCP2) and oxidative stress (GSH and carbonylated proteins) but not of ER stress (CHOP, XBP1). Additionally, HFD/STZ treatment caused a reduction in glycogen content, glucokinase activity (a limiting step in glycolysis) and expression of ChREBP gene (a de novo lipogenesis regulator), suggesting a modified glycolytic pathway. The cholesterol biosynthesis in HFD/STZ treated rats was inhibited (reduced expression of SREBP-2-regulated HMGCoA red and LDLr), instead the cholesterol catabolism was increased, as shown by the mRNA induction of the CYP7A1 and CYP8B1 (key genes for BA acid). A reduced gene expression of FXR-dependent SHP (a key gene for feedback inhibition of CYP7A1 and CYP8B1) and of bile acids (NTCP, OATP1A1, BSEP) and cholesterol (ABCA1) transporters was found. Significance: These results widely extend the characterization of HFD/STZ rat model, which might mimic the NAFLD/NASH in diabetic humans.

A high-fat diet is known to induce atherosclerosis in animal models. Dietary factors and timing of atherogenic food delivery may affect plasma lipoprotein content composition and its potential atherogenic effect. Increasingly often, humans spend periods/days eating in a completely unregulated way, ingesting excessive amounts of food rich in oils and fats, alternating with periods/days when food intake is more or less correct. We investigate the effect on lipid homeostasis of a high-fat diet administered either continuously or intermittently. We investigated control pigs receiving standard diet (C, n=7), pigs receiving a high-fat diet every day for 10 weeks (CHF, n=5), and pigs receiving a high-fat diet every other week for 10 weeks (IHF, n=7). IHF animals were shown to have a different lipid profile compared with CHF animals, with a significant increase in high-density lipoproteins (HDL) levels with respect to C and CHF groups. CHF also showed significantly higher values of TC/HDL cholesterol compared with C and IHF. Hepatic expression analysis of genes involved in lipid homeostasis showed an increasing trend of nuclear receptor LXRα along with its target genes in the CHF group and in the IHF group, whereas SREBP2 and LDLr were significantly inhibited. A significant correlation was found between ABCA1 expression and circulating levels of HDL-C. Periodic withdrawals of a high-fat atherogenic diet compared with a regular administration results in a different adaptive response of lipoprotein metabolism, which leads to a significantly higher plasma level of HDL-C and lower TC/HDL-C.