The anti-proliferative effects of adiponectin on human lung adenocarcinoma A549 cells and oxidative stress involvement.

Adiponectin (Acrp30) plays an important role in energy metabolism and inflammation. Recently, in vivo serum Acrp30 levels have been reported to be correlated to risk of developing several types of cancers such as lung cancer, and in vitro studies have demonstrated a role for Acrp30 in the control of cell proliferation and survival. However, the molecular effects of Acrp30 on lung cancer have not yet been clearly defined. In the present study, we investigated the effects of different concentrations of Acrp30 on the A549 human alveolar epithelial cell line, an in vitro model of lung adenocarcinoma. A549 cells were exposed to various concentrations of Acrp30 and successively, proliferation, apoptosis and oxidative stress were evaluated by MTT test, caspase activity assay, flow-cytometry and western blotting analysis. Our results demonstrated that Acrp30 causes, in a time- and dose-dependent manner, a reduction of cell viability and duplication together with an increase in cell apoptosis rate. In addition, we found that Acrp30 induces an increase of lipid peroxidation evaluated by TBARS assay and a concomitant reduction of nitric oxide release, both markers of cellular oxidative stress. Taken together, our data on A549 cells provides new insight into potential involvement of Acrp30 on physio-pathologic mechanisms of lung diseases through interference with proliferation, apoptosis and oxidative status.

Adiponectin profile at baseline is correlated to progression and severity of multiple sclerosis.

BACKGROUND AND PURPOSE: Adiponectin is a cytokine linking energy metabolism and immune system. After being assembled, adiponectin circulates as oligomers of different molecular weight, i.e. low, medium and high (HMW) molecular weight. These have the most potent biological effects. Multiple sclerosis (MS) is an autoimmune disease of the human central nervous system. The aim of this study was to characterize the expression levels of both total adiponectin and its oligomerization state in the serum from 99 patients with MS at baseline (i.e. not influenced by therapies). We also investigated the potential relationships between adiponectin and disease progression and severity. METHODS: Adiponectin was quantified and visualized by enzyme-linked immunosorbent assay, western blotting and fast protein liquid chromatography. During the follow-up (3.6 ± 2.20 years), the patients were evaluated using total annualized relapse rate and Expanded Disability Status Scale score. RESULTS: Total adiponectin is statistically higher in patients with MS compared with matched controls (12.18 vs. 10.02 µg/mL, P = 0.001). Interestingly, the adiponectin oligomerization state is altered in MS, with an increase of HMW oligomers. In addition, patients with MS with higher levels of adiponectin at baseline have significantly higher risk of progression and severity (Multiple Sclerosis Severity Score, 3.84 vs. 2.44, P = 0.001). No statistical difference in adiponectin expression was found between active and inactive patients with MS and among the different forms of disease. CONCLUSIONS: This study demonstrated that adiponectin and its HMW oligomers are greatly involved in MS autoimmune disorder representing a potential biomarker to predict worse MS prognosis and severity. Further studies are required to clarify the molecular mechanisms underlying the properties of adiponectin and HMW oligomers in MS.

Adiponectin and colon cancer: evidence for inhibitory effects on viability and migration of human colorectal cell lines.

Adiponectin (Acrp30) is an adipokine widely studied for its beneficial metabolic and anti-inflammatory properties. Colorectal cancer is among the most common cancers worldwide. The aim of present study was to explore the effects of Acrp30 on both CaCo-2 and HCT116 colorectal cancer cells in terms of viability, oxidative stress, and apoptosis. In addition, since colorectal cancer represents a typical inflammation-related cancer, we investigated whether Acrp30 treatment modifies the migration and the expression of crucial proteins in the EMT transition. Finally, we analyzed the expression of cytokines in CaCo-2 cells. We found that Acrp30 reduces the survival rate of both CaCo-2 and HCT116 cells through induction of apoptosis and oxidative stress already after 24 h of treatment. In addition, wound-healing assay indicated that Acrp30 exposure statistically inhibits CaCo-2 and HCT116 cell migration. Western blot analysis performed on E-cadherin and vimentin, two EMT crucial markers in carcinogenesis, indicated that Acrp30 does not influence EMT transition. Finally, we found a reduction of mRNA levels corresponding to the anti-inflammatory IL-10 cytokine together with an increase of the pro-inflammatory IL-6 and IL-8 cytokines. This study provides new insight into Acrp30 molecular effects on colorectal cancer cells. Indeed, even if further studies are necessary to clarify the precise role of Acrp30 in colorectal cancer, our data strongly suggest that Acrp30 negatively regulates cell survival and migration in association with induction of oxidative stress and regulation of cytokines expression in both CaCo-2 and HCT116 colorectal cells.

Differentially expressed and activated proteins associated with non small cell lung cancer tissues.

BACKGROUND: Lung cancer is a leading cause of mortality. The most common cancer subtype, non small cell lung cancer (NSCLC), accounts for 85-90% all cases and is mainly caused by environmental and genetic factors. Mechanisms involved in lung carcinogenesis include deregulation of several kinases and molecular pathways affecting cell proliferation, apoptosis and differentiation. Despite advances in lung cancer detection, diagnosis and staging, survival rate still remains poor and novel biomarkers for both diagnosis and therapy need to be identified. In the present study, we have explored the potential of novel specific biomarkers in the diagnosis of NSCLC, and the over-expression/activation of several kinases involved in disease development and progression. METHOD: Lung tumor tissue specimens and adjacent cancer-free tissues from 8 NSCLC patients undergoing surgery were collected. The differential activation status of ERK1/2, AKT and IKBα/NF-κß was analyzed. Subsequently, protein expression profile of NSCLC vs normal surrounding tissue was compared by a proteomic approach using LC-MS MS. Subsequently, MS/MS outputs were analyzed by the Protein Discoverer platform for label-free quantitation analysis. Finally, results were confirmed by western blotting analysis. RESULTS: This study confirms the involvement of ERK1/2, AKT, IKBα and NF-κß proteins in NSCLC demonstrating a significant over-activation of all tested proteins. Furthermore, we found significant differential expression of 20 proteins (Rsc ≥ 1.50 or ≤ -1.50) of which 7 are under-expressed and 13 over-expressed in NSCLC lung tissues. Finally, we validated, by western blotting, the two most under-expressed NSCLC tissue proteins, carbonic anhydrase I and II isoforms. CONCLUSION: Our data further support the possibility of developing both diagnostic tests and innovative targeted therapy in NSCLC. In addition to selective inhibitors of ERK1/2, AKT, IKBα and NF-κß, as therapeutic options, our data, for the first time, indicates carbonic anhydrase I and II as attractive targets for development of diagnostic tools enabling selection of patients for a more specific therapy in NSCLC.

Evaluation of salivary adiponectin profile in obese patients.

Obesity is a chronic inflammatory disease significantly risen worldwide, especially among children. Adipokines, secreted from adipose tissue, are hormones involved in various cellular processes such as energy metabolism and inflammation. Among the others, adiponectin is gaining increasing interest for its insulin-sentitizing, anti-atherogenic and anti-inflammatory properties. This adipokine undergoes different post-translational modifications, after which it circulates as oligomers of high, medium and low molecular weight (HMW, MMW, LMW); HMW are the most biologically active oligomers. Serum adiponectin levels as well as the amount of its oligomers are inversely correlated to BMI and closely associated with obesity and related diseases. In this study, we analyzed total adiponectin expression and its oligomeric profile in saliva samples from 27 obese compared to 27 age- and sex-matched controls. Moreover, we compared adiponectin oligomerization between serum and saliva samples. The analysis of the different adiponectin oligomers reveals a slightly higher expression of total, HMW and LMW salivary adiponectin in obese patients compared to controls. Finally, FPLC analysis evidenced that HMW oligomers in saliva have a higher molecular weight than in serum confirming the presence of more complex oligomers in saliva, previously identified as super HMW (S-HMW). Saliva is considered a potential source of novel biomarkers for the diagnosis of metabolic disorders. The assessment of total adiponectin and its oligomeric profiles in saliva samples may represent a promising biological marker for the analysis of metabolic diseases.

Tissue-specific downregulation of the adiponectin "system": possible implications for fat accumulation tendency in the pig.

Adiponectin's beneficial effects are mediated by the AdipoR1 and AdipoR2 receptors (AdipoRs). The pig is a good model to study complex disorders such as obesity. We analyzed the expression of adiponectin, AdipoRs and some key molecules of energy metabolism (AMP-activated protein kinase α [AMPKα], p38 mitogen-activated protein kinase [p38 MAPK], and PPARα) in 2 pig breeds that displayed an opposite genetic behavior for energy metabolism: Casertana (CE), a fat-type animal, and Large White (LW), a lean-type animal. Muscle, liver, visceral and subcutaneous adipose tissues, and brain tissues were examined. The AdipoRs cDNA sequences were identical in the 2 breeds. AdipoRs mRNA expression, measured in all tissues, was significantly lower only in the 2 adipose tissues of CE pigs (P < 0.05). The muscle expression of AdipoRs, AMPKα, p38 MAPK, and PPARα was lower in CE than in LW animals (P < 0.01, P < 0.05, P < 0.01, P < 0.01, respectively). In liver, no molecule differed between breeds. The expression of both AdipoRs in visceral and subcutaneous adipose tissues was lower in CE pigs (P < 0.01). In brain, AdipoR1 and AMPKα expression was lower in CE pigs (P < 0.01), whereas AdipoR2 tended to be lower in CE than LW pigs (P = 0.05). In conclusion, our results suggest that tissue-specific downregulation of Adiponectin, AdipoRs, and of the key molecules of energy metabolism may be associated with the tendency of CE pigs to accumulate fat.

Neurophysiological assessment in the diagnosis of botulism: usefulness of single-fiber EMG.

We report the clinical, serological, and neurophysiological findings in seven patients with foodborne botulism caused by ingestion of black olives in water. The clinical picture was characterized by mild symptoms with a long latency of onset and by involvement of cranial and upper limb muscles; only one patient, a child, developed respiratory failure. Spores of Clostridium botulinum were found in stools in some but not all cases. Conventional neurophysiological tests had low sensitivity; abnormal findings were present only in the patient with severe clinical involvement, in whom compound muscle action potentials (CMAPs) appeared reduced. Repetitive nerve stimulation at a high rate showed pseudofacilitation and not true posttetanic facilitation, but single-fiber electromyography (SFEMG) showed abnormalities of neuromuscular transmission in every case. Neurophysiological evaluation, particularly SFEMG, is important because it allows rapid identification of abnormal neuromuscular transmission while bioassay studies are in progress.