Claudia Sangiorgi

Alcoholic Liver Disease: A Mouse Model Reveals Protection by Lactobacillus fermentum

Objectives:Alcoholism is one of the most devastating diseases with high incidence, but knowledge of its pathology and treatment is still plagued with gaps mostly because of the inherent limitations of research with patients. We developed an animal model for studying liver histopathology, Hsp (heat-shock protein)-chaperones involvement, and response to treatment.Methods:The system was standardized using mice to which ethanol was orally administered alone or in combination with Lactobacillus fermentum following a precise schedule over time and applying, at predetermined intervals, a battery of techniques (histology, immunohistochemistry, western blotting, real-time PCR, immunoprecipitation, 3-nitrotyrosine labeling) to assess liver pathology (e.g., steatosis, fibrosis), and Hsp60 and iNOS (inducible form of nitric oxide synthase) gene expression and protein levels, and post-translational modifications.Results:Typical ethanol-induced liver pathology occurred and the effect of the probiotic could be reliably monitored. Steatosis score, iNOS levels, and nitrated proteins (e.g., Hsp60) decreased after probiotic intake.Conclusions:We describe a mouse model useful for studying liver disease induced by chronic ethanol intake and for testing pertinent therapeutic agents, e.g., probiotics. We tested L. fermentum, which reduced considerably ethanol-induced tissue damage and deleterious post-translational modifications of the chaperone Hsp60. The model is available to test other agents and probiotics with therapeutic potential in alcoholic liver disease.

Skeletal muscle Heat shock protein 60 increases after endurance training and induces peroxisome proliferator-activated receptor gamma coactivator 1 α1 expression.

Heat shock protein 60 (Hsp60) is a chaperone localizing in skeletal muscle mitochondria, whose role is poorly understood. In the present study, the levels of Hsp60 in fibres of the entire posterior group of hindlimb muscles (gastrocnemius, soleus, and plantaris) were evaluated in mice after completing a 6-week endurance training program. The correlation between Hsp60 levels and the expression of four isoforms of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) were investigated only in soleus. Short-term overexpression of hsp60, achieved by in vitro plasmid transfection, was then performed to determine whether this chaperone could have a role in the activation of the expression levels of PGC1α isoforms. The levels of Hsp60 protein were fibre-type specific in the posterior muscles and endurance training increased its content in type I muscle fibers. Concomitantly with the increased levels of Hsp60 released in the blood stream of trained mice, mitochondrial copy number and the expression of three isoforms of PGC1α increased. Overexpressing hsp60 in cultured myoblasts induced only the expression of PGC1 1α, suggesting a correlation between Hsp60 overexpression and PGC1 1 α activation.

Effects of Nandrolone Stimulation on Testosterone Biosynthesis in Leydig Cells.

Anabolic androgenic steroids (AAS) are among the drugs most used by athletes for improving physical performance, as well as for aesthetic purposes. A number of papers have showed the side effects of AAS in different organs and tissues. For example, AAS are known to suppress gonadotropin‐releasing hormone, luteinizing hormone, and follicle‐stimulating hormone. This study investigates the effects of nandrolone on testosterone biosynthesis in Leydig cells using various methods, including mass spectrometry, western blotting, confocal microscopy and quantitative real‐time PCR. The results obtained show that testosterone levels increase at a 3.9 μM concentration of nandrolone and return to the basal level a 15.6 μM dose of nandrolone. Nandrolone‐induced testosterone increment was associated with upregulation of the steroidogenic acute regulatory protein (StAR) and downregulation of 17a‐hydroxylase/17, 20 lyase (CYP17A1). Instead, a 15.6 µM dose of nandrolone induced a down‐regulation of CYP17A1. Further in vivo studies based on these data are needed to better understand the relationship between disturbed testosterone homeostasis and reproductive system impairment in male subjects. J. Cell. Physiol. 231: 1385–1391, 2016.

Nandrolone decanoate interferes with testosterone biosynthesis altering blood–testis barrier components

The aim of this study was to investigate whether nandrolone decanoate (ND) use affects testosterone production and testicular morphology in a model of trained and sedentary mice. A group of mice underwent endurance training while another set led a sedentary lifestyle and were freely mobile within cages. All experimental groups were treated with either ND or peanut oil at different doses for 6 weeks. Testosterone serum levels were measured via liquid chromatography–mass spectrometry. Western blot analysis and quantitative real‐time PCR were utilized to determine gene and protein expression levels of the primary enzymes implicated in testosterone biosynthesis and gene expression levels of the blood–testis barrier (BTB) components. Immunohistochemistry and immunofluorescence were conducted for testicular morphological evaluation. The study demonstrated that moderate to high doses of ND induced a diminished serum testosterone level and altered the expression level of the key steroidogenic enzymes involved in testosterone biosynthesis. At the morphological level, ND induced degradation of the BTB by targeting the tight junction protein‐1 (TJP1). ND stimulation deregulated metalloproteinase‐9, metalloproteinase‐2 (MMP‐2) and the tissue inhibitor of MMP‐2. Moreover, ND administration resulted in a mislocalization of mucin‐1. In conclusion, ND abuse induces a decline in testosterone production that is unable to regulate the internalization and redistribution of TJP1 and may induce the deregulation of other BTB constituents via the inhibition of MMP‐2. ND may well be considered as both a potential inducer of male infertility and a potential risk factor to a low endogenous bioavailable testosterone.

Effects of Conjugated Linoleic Acid Associated With Endurance Exercise on Muscle Fibres and Peroxisome Proliferator-Activated Receptor γ Coactivator 1 α Isoforms

Conjugated linoleic acid (CLA) has been reported to improve muscle hypertrophy, steroidogenesis, physical activity, and endurance capacity in mice, although the molecular mechanisms of its actions are not completely understood. The aim of the present study was to identify whether CLA alters the expression of any of the peroxisome proliferator‐activated receptor γ coactivator 1α (PGC1α) isoforms, and to evaluate the possible existence of fibre‐type‐specific hypertrophy in the gastrocnemius and plantaris muscles. Mice were randomly assigned to one of four groups: placebo sedentary, CLA sedentary, placebo trained, or CLA trained. The CLA groups were gavaged with 35 μl per day of Tonalin® FFA 80 food supplement containing CLA throughout the 6‐week experimental period, whereas the placebo groups were gavaged with 35 μl sunflower oil each day. Each administered dose of CLA corresponded to approximately 0.7 g/kg or 0.5%, of the dietary daily intake. Trained groups ran 5 days per week on a Rota‐Rod for 6 weeks at increasing speeds and durations. Mice were sacrificed by cervical dislocation and hind limb posterior muscle groups were dissected and used for histological and molecular analyses. Endurance training stimulated mitochondrial biogenesis by PGC1α isoforms (tot, α1, α2, and α3) but CLA supplementation did not stimulate PGC1α isoforms or mitochondrial biogenesis in trained or sedentary mice. In the plantaris muscle, CLA supplementation induced a fibre‐type‐specific hypertrophy of type IIx muscle fibres, which was associated with increased capillary density and was different from the fibre‐type‐specific hypertrophy induced by endurance exercise (of types I and IIb muscle fibres). J. Cell. Physiol. 232: 1086–1094, 2017.

TGF-β Signaling Pathways in Different Compartments of the Lower Airways of Patients With Stable COPD

BACKGROUND: The expression and localization of transforming growth factor‐&bgr; (TGF‐&bgr;) pathway proteins in different compartments of the lower airways of patients with stable COPD is unclear. We aimed to determine TGF‐&bgr; pathway protein expression in patients with stable COPD. METHODS: The expression and localization of TGF‐&bgr; pathway components was measured in the bronchial mucosa and peripheral lungs of patients with stable COPD (n = 44), control smokers with normal lung function (n = 24), and control nonsmoking subjects (n = 11) using immunohistochemical analysis. RESULTS: TGF‐&bgr;1, TGF‐&bgr;3, and connective tissue growth factor expression were significantly decreased in the bronchiolar epithelium, with TGF‐&bgr;1 also decreased in alveolar macrophages, in patients with stable COPD compared with control smokers with normal lung function. TGF‐&bgr;3 expression was increased in the bronchial lamina propria of both control smokers with normal lung function and smokers with mild/moderate stable COPD compared with control nonsmokers and correlated significantly with pack‐years of smoking. However, TGF‐&bgr;3+ cells decreased in patients with severe/very severe COPD compared with control smokers. Latent TGF‐&bgr; binding protein 1 expression was increased in the bronchial lamina propria in subjects with stable COPD of all severities compared with control smokers with normal lung function. Bone morphogenetic protein and activin membrane‐bound inhibitor expression (BAMBI) in the bronchial mucosa was significantly increased in patients with stable COPD of all severities compared with control subjects. No other significant differences were observed between groups for all the other molecules studied in the bronchial mucosa and peripheral lung. CONCLUSIONS: Expression of TGF‐&bgr;s and their regulatory proteins is distinct within different lower airway compartments in stable COPD. Selective reduction in TGF‐&bgr;1 and enhanced BAMBI expression may be associated with the increase in autoimmunity in COPD.

HSP60 activity on human bronchial epithelial cells

HSP60 has been implicated in chronic inflammatory disease pathogenesis, including chronic obstructive pulmonary disease (COPD), but the mechanisms by which this chaperonin would act are poorly understood. A number of studies suggest a role for extracellular HSP60, since it can be secreted from cells and bind Toll-like receptors; however, the effects of this stimulation have never been extensively studied. We investigated the effects (pro- or anti-inflammatory) of HSP60 in human bronchial epithelial cells (16-HBE) alone and in comparison with oxidative, inflammatory, or bacterial challenges. 16-HBE cells were cultured for 1–4 h in the absence or presence of HSP60, H2O2, lipopolysaccharide (LPS), or cytomix. The cell response was evaluated by measuring the expression of IL-8 and IL-10, respectively, pro- and anti-inflammatory cytokines involved in COPD pathogenesis, as well as of pertinent TLR-4 pathway mediators. Stimulation with HSP60 up-regulated IL-8 at mRNA and protein levels and down-regulated IL-10 mRNA and protein. Likewise, CREB1 mRNA was up-regulated. H2O2 and LPS up-regulated IL-8. Experiments with an inhibitor for p38 showed that this mitogen-activated protein kinase could be involved in the HSP60-mediated pro-inflammatory effects. HSP60 showed pro-inflammatory properties in bronchial epithelial cells mediated by activation of TLR-4-related molecules. The results should prompt further studies on more complex ex-vivo or in-vivo models with the aim to elucidate further the role of those molecules in the pathogenesis of COPD.

A mouse model of alcoholic liver disease reveals protection by Lactobacillus fermentum

The knowledge and treatment of alcoholic liver disease is still plagued with gaps mostly due to the inherent limitations of research with patients. We developed an animal model for studying liver histopathology, Hsp-chaperones involvement, and response to treatment. The system was standardized using mice to which ethanol was orally administered alone or in combination with Lactobacillus fermentum for 4, 8 and 12 weeks and applying a battery of techniques (histology, immunohistochemistry, Western blotting, real-time PCR, immunoprecipitation, 3-nitrotyrosine labeling) to assess liver pathology and Hsp60, iNOS gene expression and protein levels, and Hsp60 post-translational modifications. Steatosis score, iNOS levels, and nitrosylated proteins (e.g., Hsp60) decreased after probiotic intake reducing considerably ethanol-induced tissue damage. However, one may assume that the probiotic tested has a gut protective effect and, possibly, anti-steatotic and antioxidant effects in the liver. Our results provide novel insights that may be taken into account while devising new approaches for treating liver diseases associated with alcohol consumption (1).

Hsp60 and interleukins expression in the skeletal muscle and its implications in exercise and cachexia

Heat shock protein 60 (Hsp60) is a chaperon localizing in skeletal muscle mitochondria, whose role is poorly understood. This chaperone has been found also in other cellular localizations. In the three years we studied the levels of Hsp60 in fibres of the entire posterior group of hindlimb muscles (gastrocnemius, soleus, and plantaris) in mice after completing a 6-week endurance training program. In this evaluation we correlated Hsp60 levels with the expression of four isoforms of the peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α). Moreover, the short-term overexpression of hsp60, achieved by in vitro plasmid transfection was performed to determine whether this chaperon could have a role in the activation of the expression levels of PGC-1α isoforms. The levels of Hsp60 protein were fibre-type specific in the posterior muscles and endurance training increased its content in type I muscle fibers. Concomitantly with the increased levels of Hsp60 released in the blood stream of trained mice, mitochondrial copy number and the expression of three isoforms of PGC-1α increased. Overexpressing hsp60 in cultured myoblasts induced only the expression of PGC-1 α1, suggesting a correlation between Hsp60 overexpression and PGC-1 α1 activation. We are now studying the expression of Hsp60 in the muscles of trained and untrained C26-bearing mice, to understand if Hsp60 over expression may improve muscle performance and reduce cachexia. Four different interleukins have been also studied in cachectic mice, to understand which can be the effect of them on Hsp60 expression both in the tumor mass and the trained muscle.This work was funded by PRIN2009 - Prof. G. Zummo and PRIN2012 - Prof. Farina F.

Skeletal muscle heat shock protein 60 increases after endurance training in mice and induces peroxisome proliferation-activated receptor-γ coactivator-1 α1 expression

Heat shock protein (Hsp60) is a mitochondrial chaperonin whose unconventional cellular localizations and functions are discovered day by day. In the present study, the levels of Hsp60 in fibres of the soleus muscle and its correlation to the expression of four isoforms of peroxisome proliferation-activated receptor-γ (PPAR-γ) coactivator-1α (PGC1α) were investigated in 72 young (7-weeks old) healthy male mice (BALB/c AnNHsd) at baseline and after completing a 6-week endurance training program. The mice were assigned to one of the two experimental groups: SED (sedentary) or TR (trained). Short-term overexpression of hsp60, achieved by in vitro plasmid transfection, was then performed to determine whether this chaperonin could have a role in the activation of the expression levels of PGC-1α isoforms. The levels of Hsp60 protein were fibre-type specific in the posterior muscles at baseline, and endurance training increased its content in type I muscle fibers. Concomitantly with the increased levels of Hsp60 released in the blood stream of trained mice, mitochondrial copy number and the expression of three isoforms of PGC-1α increased. Overexpressing hsp60 in cultured myoblasts induced only the expression of PGC-1 α1, letting us suppose a direct correlation between Hsp60 overexpression and PGC-1 α1 activation. Overall, these results suggest that during endurance training Hsp60 is upregulated and activates the mitochondrial biogenesis pathway, probably as a response to the oxidative stress induced by exercise. This study reveals a molecular response of skeletal muscle to a mechanical stress induced by training which involves the molecular chaperonin Hsp60 and the transcriptional co-activator PGC-1 α1. The role of these proteins in aerobic adaptation and pathological conditions as cancer cachexia warrants further investigations.