Effect of conjugated linoleic acid on testosterone levels in vitro and in vivo after an acute bout of resistance exercise.

The purposes of the present study were to investigate the effect of conjugated linoleic acid (CLA) supplementation on testosterone levels in vitro on a cell line derived from Leydig cells (R2C) and in vivo in the blood of physically active subjects before and after a resistance exercise bout. In vitro R2C cells were treated with different CLA concentrations (0-30 μM) for 24 and 48 hours. After treatment, supernatant media were tested to determine testosterone secretion. The CLA increased the testosterone secretion only after 48 hours. In vivo, 10 resistance-trained male subjects, in a double-blind placebo-controlled and crossover study design were randomized for 3 weeks of either 6 g·d⁻¹ CLA or placebo. Blood was drawn pre and post each resistance exercise bout to determine the total testosterone and sex hormone-binding globulin (SHBG) levels. No significant differences were observed for total testosterone or SHBG pre and post each resistance exercise bout; although after the resistance exercise bouts, total testosterone increased moderately (effect size = moderate), whereas after CLA supplementation, there was a large increase in total testosterone (effect size = large). CLA supplementation induced an increase in testosterone levels in Leydig cells in vitro after 48 hours but not in vivo before and after a resistance exercise bout. These findings suggest that CLA supplementation may promote testosterone synthesis through a molecular pathway that should be investigated in the future, although this effect did not have an anabolic relevance in our in vivo model

Quantitative patterns of Hsps in tubular adenoma compared with normal and tumor tissues reveal the value of Hsp10 and Hsp60 in early diagnosis of large bowel cancer

Large bowel carcinogenesis involves accumulation of genetic alterations leading to transformation of normal mucosa into dysplasia and, lastly, adenocarcinoma. It is pertinent to elucidate the molecular changes occurring in the pre-neoplastic lesions to facilitate early diagnosis and treatment. Heat shock proteins (Hsps), many of which are molecular chaperones, are implicated in carcinogenesis, and their variations with tumor progression encourage their study as biomarkers. There are many reports on Hsps and cancer but none to our knowledge on their systematic quantification in pre-neoplastic lesions of the large bowel. We performed immunohistochemical determinations of Hsp10, Hsp60, Hsp70, and Hsp90 in biopsies of large bowel tubular adenomas with moderate grade of dysplasia and compared to normal mucosa and adenocarcinoma with a moderate grade of differentiation (G2). A significant elevation of Hsp10 and Hsp60 only, i.e., in the absence of elevation of Hsp70 or Hsp90, in both epithelium and lamina propria was found in tubular adenoma by comparison with normal mucosa. In contrast, adenocarcinoma was characterized by the highest levels of Hsp10 and Hsp60 in epithelium and lamina propria, accompanied by the highest levels of Hsp70 only in epithelium and of Hsp90 only in lamina propria, by comparison with normal and tubular adenoma counterparts. Hsp10 and Hsp60 are promising biomarkers for early diagnosis of tubular adenoma and for its differentiation from more advanced malignant lesions. Hsp10 and Hsp60 may be implicated in carcinogenesis from its very early steps and, thus, are potentially convenient targets for therapy

Medium-Term Culture of Primary Oral Squamous Cell Carcinoma in a Three-Dimensional Model: Effects on Cell Survival Following Topical 5-Fluororacile Delivery by Drug-Loaded Matrix Tablets

Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting side-effects, the design of formulations for local application on malignant lesions seems to be an efficient and promising drug delivery approach. In this study, the effect of locally applied 5-FU on cell death was evaluated both in a SCC4/HEK001 model and in a newly proposed 3D outgrowth model of oral squamous cell carcinoma (OSCC). Initially, the optimal drug dose was established by delivery of solutions containing different amounts of 5-FU. The solution containing 1% (w/v) of 5-FU resulted effective in inducing cell death with complete eradication of cell colonies. Buccal tablets were designed to deliver 5-FU locoregionally to the cancer lesions of the oral cavity. Tablets were prepared using a drug loaded matrix of acrylic/methacrylic acid copolymer containing 1% (w/w) of 5-FU and applied on 3D outgrowths. The drug release from tablets appeared to be sufficient to induce cell death as confirmed by transmission electron microscopy and enzymatic assay (TUNEL). After 120 h of treatment, when about 90% of the drug had been discharged from the tablets into the culture environment, 5-FU caused loss of cell-cell communications and apoptotic cell death. After 192 h, a complete disaggregation of the 3D oral outgrowths and the death of all the cells was observed. Buccal matrix tablets could be considered a promising new approach to the locoregional treatment of OSCC. Risks of systemic toxicity are avoided since very low drug doses are delivered

Conjugated linoleic acid (CLA) stimulates mitochondrial biogenesis by PGC-1alpha in trained mice

Conjugated linoleic acid (CLA) has been reported to improve muscle hypertrophy, steroidogenesis, physical activity and endurance capacity in mice (1,2), however the mode of action is not completely understood. The aims of the present study were to identify the pathway stimulated by CLA supplementation on mitochondrial biogenesis, one of the most important adaptive response in skeletal muscle after endurance exercise. Mice were randomly assigned to one of four groups (n = 8 per group): placebo sedentary (PLA-SED); CLA sedentary (CLA-SED); placebo trained (PLA-TR); or CLA trained (CLA-TR). The CLA groups were gavaged with 35 μL per day (corresponding to the 0.5% of food ingested, approximately 4 g) Tonalin® FFA 80 food supplement containing CLA throughout the 6 week experimental period, while the placebo groups were gavaged with 35 μL per day sunflower oil. Trained groups performed progressive running on the rotarod for 6 weeks at increasing speed and duration (3). Preliminary findings may suggest that CLA supplementation potentiate mitochondrial biogenesis in trained skeletal muscle via PGC-1 alpha, although further studies need to be conducted to delineate the signaling cascade

Upon oxidative stress, the antiapoptotic Hsp60/procaspase-3 complex persists in mucoepidermoid carcinoma cells.

Hsp60, a mitochondrial chaperonin highly conserved during evolution, has been found elevated in the cytosol of cancer cells, both in vivo and in vitro, but its role in determining apoptosis during oxidative stress (OS) has not yet been fully elucidated. The aim of the present work was to study the effects of OS on Hsp60 levels and its interactions with procaspase- 3 (p-C3) and p53 in tumor cells. NCI-H292 (mucoepidermoid carcinoma) cells were exposed to various concentrations of hydrogen peroxide (H2O2) for 24 hours. Cell viability was determined by Trypan blue and MTT assays. DNA damage was assessed by the Comet assay, and apoptosis was measured by the AnnexinV cytofluorimetric test. Exposure to increasing concentrations of H2O2 resulted in a reduction of cell viability, DNA damage, and early apoptotic phenomena. Hsp60, p-C3, p53, and p21 were assessed by Western blotting and immunocytochemistry before and after OS. Hsp60 and p-C3 were present before and after OS induction. Immunoprecipitation experiments showed an Hsp60/p-C3 complex before OS that persisted after it, while an Hsp60/p53 complex was not detected in either condition. The presence of wild type (wt) p53 was confirmed by RT-PCR, and p21 detection suggested p53 activation after OS. We postulate that, although OS may induce early apoptosis in NCI-H292 cells, Hsp60 exerts an anti-apoptotic effect in these cells and, by extension, it may do so in other cancer cell

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

Tissue engineering for the development of threedimensional in vitro models of human mucosae

The recent progress in the biomaterials field and the need for novel 3D cell culture models has led us to develop a new model, the 3D mucosal outgrowth, with advanced characteristics: the simultaneous presence of two differentiated cytotypes (a polarized epithelium above a fibroblastic layer), a complex extracellular matrix (ECM) and the possibility for long-term exposures. This model can be used to grow different human mucosae in vitro, with two types of support scaffolds, a porous polyethylene terephthalate (PET) membrane, for which the model was initially developed, and a poly-L-lactide (PLLA) membrane that was later adapted to the model due to its biodegradability. A fragment of the tissue of interest is placed on the membrane and embedded within a synthetic extra cellular matrix; during the culture period, cells start to grow outwards from the central biopsy and form a new mucosa. Outgrowths grown on PET and PLLA were characterised morphologically by electron microscopy, and immunotyped by immunofluorescence and immunohistochemistry. When grown on PET, all tested mucosae (bronchial, oral and colorectal) showed good differentiation of the relevant cytotypes and proper organization of the ECM. For this reason, they were used for functional studies. Outgrowths developed on PLLA instead, showed a lower degree of cell differentiation and a tendency to form tubular growths that stained positively for endothelial markers. Further evaluations are needed to verify the possibility to use PLLA as a support scaffold for this model

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