A morphometric study of human submandibular gland in type 2 diabetic status

Diabetes Mellitus Type 2 represents one of the principal diseases that afflict the world population. It is well documented that diabetes affects both morphology and function of several organs. In diabetic rats significant structural changes have been demonstrated in salivary glands, such as accumulation of secretory material and lipid droplets within secretory cells, parenchymal degeneration and its replacement with fibrous connective tissue (1). With regard to human salivary glands, the data are scanty and conflicting. Our work, carried out by light and electron microscopy, is based on the evaluation of the morphological changes which occur in human submandibular glands of diabetic with respect to non diabetic patients. Surgical fragments of glandular tissue were fixed, dehydrated, and processed for light and electron microscopy. Randomly chosen images were analyzed with Image Pro Plus software to record the dimension of acini, serous cells, secretory granules and other variables. Data were analyzed by Student’s t-test and Mann Whitney test. In diabetic glands statistically significant morphological changes were observed, such as enlargement of serous acini and increase of secretory granules area. These results suggest that the secretory activity of human submandibular gland is severely affected by the diabetic status. Obviously these data need to be confirmed with further measurements in order to explain better how diabetes affects human salivary glands

Management of Obesity and Obesity-Related Disorders: From Stem Cells and Epigenetics to Its Treatment

: Obesity is a complex worldwide disease, characterized by an abnormal or excessive fat accumulation. The onset of this pathology is generally linked to a complex network of interactions among genetic and environmental factors, aging, lifestyle, and diets. During adipogenesis, several regulatory mechanisms and transcription factors are involved. As fat cells grow, adipose tissue becomes increasingly large and dysfunctional, losing its endocrine function, secreting pro-inflammatory cytokines, and recruiting infiltrating macrophages. This long-term low-grade systemic inflammation results in insulin resistance in peripheral tissues. In this review we describe the main mechanisms involved in adipogenesis, from a physiological condition to obesity. Current therapeutic strategies for the management of obesity and the related metabolic syndrome are also reported

A morphometric study of human submandibular gland in type 2 diabetic status

Diabetes Mellitus Type 2 represents one of the principal diseases that afflict the world population. It is well documented that diabetes affects both morphology and function of several organs. In diabetic rats significant structural changes have been demonstrated in salivary glands, such as accumulation of secretory material and lipid droplets within secretory cells, parenchymal degeneration and its replacement with fibrous connective tissue (1). With regard to human salivary glands, the data are scanty and conflicting. Our work, carried out by light and electron microscopy, is based on the evaluation of the morphological changes which occur in human submandibular glands of diabetic with respect to non diabetic patients. Surgical fragments of glandular tissue were fixed, dehydrated, and processed for light and electron microscopy. Randomly chosen images were analyzed with Image Pro Plus software to record the dimension of acini, serous cells, secretory granules and other variables. Data were analyzed by Student’s t-test and Mann Whitney test. In diabetic glands statistically significant morphological changes were observed, such as enlargement of serous acini and increase of secretory granules area. These results suggest that the secretory activity of human submandibular gland is severely affected by the diabetic status. Obviously these data need to be confirmed with further measurements in order to explain better how diabetes affects human salivary glands. Maria Alberta Lilliu gratefully acknowledges Sardinia Regional Government for the financial support of her PhD scholarship (P.O.R. Sardegna F.S.E. Operational Programme of the Autonomous Region of Sardinia, European Social Fund 2007-2013 - Axis IV Human Resources, Objective l.3, Line of Activity l.3.1.). Michela Isola gratefully acknowledges Sardinia Regional Government for the financial support (P.O.R. Sardegna F.S.E. Operational Programme of the Autonomous Region of Sardinia, European Social Fund 2007-2013 - Axis IV Human Resources, Objective l.3, Line of Activity l.3.1 “Avviso di chiamata per il finanziamento di Assegni di Ricerca”)

Animal models are reliably mimicking human diseases? A morphological study that compares animal and human NAFLD

Nonalcoholic fatty liver disease (NAFLD) affects up to 20% of western population and, when untreated, it can progress from simple fatty liver or steatosis to a more severe condition, such as NASH (non alcoholic steatohepatitis) and cirrhosis (1). NAFLD is a clinical-pathological syndrome that include a wide spectrum of morphological alteration but such studies on humans are not copious, as human samples are difficult to obtain because of ethical limitations. Experimental models are crucial to study steatosis’ progression, not only for elucidating the pathogenesis of NAFLD but also in examining therapeutic effects of various agents. Animal models may be developed on genetic or nutritional basis, or a combination of both. It is important to select the best model fitted to the aim of the study. But the question that arises is: can the animal model reflect hepatic histopathology and pathophysiology of human NAFLD? This question is always neglected as well as the evaluation of ultrastructural features of NAFLD. In order to overcome this lack of investigations we compared ultrastructural features of NAFLD in an animal model and in human samples of NAFLD patients. NAFLD animal model was obtained using Sprague Dawley rats fed by a high fat diet (HFD) (71% of energy from fat), while control rats were fed by a standard diet (35% of energy from fat). Diets were given ad libitum and rats were killed after 1, 2, 3, and 4 weeks. Human specimens were obtained from patients with fatty liver disease undergoing to liver biopsies. Normal liver was taken from patients undergoing surgery for other pathologies. Hepatic steatosis and normality of the liver were assessed by parallel examinations at light microscopy, transmission and high resolution scanning electron microscopy. Light microscopy results showed that different degrees of NAFLD observed in human samples corresponded to similar morphological changes in treated rats. Ultrastructural examination revealed that in the HFD model the histopathology closely reflected that of human NAFLD, although the first did not replicate the full spectrum of the disease in humans. In summary, we showed that, at least morphologically, HFD model overlays to human NAFLD. This could point out for reliability in evaluating other pathological features in animal models. Moreover, animal HFD mimics human nutritional dysregulation that may induce the same biochemical and molecular modifications observed in human patients and might represent a more appropriate tool for studying the pathogenesis of NAFLD over genetic models (2)

In vitro bioaccessibility of phenolic acids from a commercial aleurone-enriched bread compared to a whole grain bread

Wheat aleurone, due to its potentially higher bioaccessibility and bioavailability of micronutrients and phenolic acids, could represent a useful ingredient in the production of commonly consumed cereal-based food. The aim of the present study was to investigate the in vitro bioaccessibility of phenolic acids both from an aleurone-enriched bread and from a whole grain bread. The two bread samples were firstly characterized for the phenolic acid content. An in vitro digestion was then performed in order to evaluate the release of phenolic acids. The results obtained suggest that the bioaccessibility of the phenolic acids in the aleurone-enriched bread is higher than in the whole grain bread. These in vitro results suggest the potential use of aleurone in the production of foods, and this may represent an attractive possibility to vehicle nutritionally interesting components to consumers

Melatonin and Vitamin D Interfere with the Adipogenic Fate of Adipose-Derived Stem Cells

Adipose-derived stem cells (ADSCs) represent one of the cellular populations resident in adipose tissue. They can be recruited under certain stimuli and committed to become preadipocytes, and then mature adipocytes. Controlling stem cell differentiation towards the adipogenic phenotype could have a great impact on future drug development aimed at counteracting fat depots. Stem cell commitment can be influenced by different molecules, such as melatonin, which we have previously shown to be an osteogenic inducer. Here, we aimed at evaluating the effects elicited by melatonin, even in the presence of vitamin D, on ADSC adipogenesis assessed in a specific medium. The transcription of specific adipogenesis orchestrating genes, such as aP2, peroxisome proliferator-activated receptor \u3b3 (PPAR-\u3b3), and that of adipocyte-specific genes, including lipoprotein lipase (LPL) and acyl-CoA thioesterase 2 (ACOT2), was significantly inhibited in cells that had been treated in the presence of melatonin and vitamin D, alone or in combination. Protein content and lipid accumulation confirmed a reduction in adipogenesis in ADSCs that had been grown in adipogenic conditions, but in the presence of melatonin and/or vitamin D. Our findings indicate the role of melatonin and vitamin D in deciding stem cell fate, and disclose novel therapeutic approaches against fat depots

Melatonin and Vitamin D Orchestrate Adipose Derived Stem Cell Fate by Modulating Epigenetic Regulatory Genes

Melatonin, that regulates many physiological processes including circadian rhythms, is a molecule able to promote osteoblasts maturation in vitro and to prevent bone loss in vivo, while regulating also adipocytes metabolism. In this regard, we have previously shown that melatonin in combination with vitamin D, is able to counteract the appearance of an adipogenic phenotype in adipose derived stem cells (ADSCs), cultured in an adipogenic favoring condition. In the present study, we aimed at evaluating the specific phenotype elicited by melatonin and vitamin D based medium, considering also the involvement of epigenetic regulating genes. ADSCs were cultured in a specific adipogenic conditioned media, in the presence of melatonin alone or with vitamin D. The expression of specific osteogenic related genes was evaluated at different time points, together with the histone deacetylases epigenetic regulators, HDAC1 and Sirtuins (SIRT) 1 and 2. Our results show that melatonin and vitamin D are able to modulate ADSCs commitment towards osteogenic phenotype through the upregulation of HDAC1, SIRT 1 and 2, unfolding an epigenetic regulation in stem cell differentiation and opening novel strategies for future therapeutic balancing of stem cell fate toward adipogenic or osteogenic phenotype

Human submandibular glands treated in vitro with amisulpride. An HRSEM morphological and morphometrical study

Amisulpride, alike sulpiride, is a benzamide substitute used in treating schizophrenia and dysthymia in a few European countries (1). Authors describe amisulpride as D2 and D3 receptor antagonist, and recently as 5-HT7a serotonin receptors antagonist (2). Moreover, a few case reports and clinical trials indicate amisulpride as a drug to reduce atypical antipsychotic-induced sialorrhea (3). Aim of this study is to investigate, by high resolution scanning electron microscopy (HRSEM), morphological changes induced in vitro by amisulpride in serous cells of human submandibular glands. Samples of human non-pathological submandibular glands obtained at surgery, were immersed in an oxygenated inorganic medium, according to the procedure described in our previous works (4), stimulated in vitro with amisulpride, and treated by our modification of the osmium maceration technique (5). By removing from serous cells all cytoplasmic organelles, we are able to visualize, by HRSEM, and quantify, with statistical method, the morphological changes on the surfaces of the plasmalemma involved in secretory processes. In particular, we calculated the density of microvilli, that of microbuds, and that of protrusions per µm2 of the intercellular canaliculi luminal membrane. Our results show that amisulpride acts on secretory serous cells of human submandibular glands, promoting a reduction of microvilli and an increase of microbuds density. In particular, microbuds increased density indicate the presence of microexocytosis profiles that allow secretion of protein into lumen. Whereas the clinical treatment of sialorrhea with amisulpride (3) demonstrates a reduction of saliva production, our data illustrate that this drug has peculiar effects on secretory mechanisms involved in protein secretion. 1) Mortimer AM.: Neuropsychiatr Dis Treat, 5:267-77. 2009 2) Abbas AI. et al.: Psychopharmacology, 205:E-pub. 2009 3) Kreinin A. et al.: Int Clin Psychopharmacol, 21:99-103. 2006 4) Testa Riva F. et al.: Cell Tissue Res, 324:347-52. 2006 5) Riva A. et al.: Scanning Microscopy 13:111-22. 199

Extracts from Myrtle Liqueur Processing Waste Modulate Stem Cells Pluripotency under Stressing Conditions

Nutraceuticals present in food are molecules able to exert biological activity for the prevention and treatment of various diseases, in form of pharmaceutical preparations, such as capsules, cream, or pills. Myrtus communis L. is a spontaneous Mediterranean evergreen shrub, widely known for the liqueur obtained from its berries rich in phytochemicals such as tannins and flavonoids. In the present study, we aimed to evaluate the properties of myrtle byproducts, residual of the industrial liqueur processing, in Adipose-derived stem cells (ADSCs) induced at oxidative stress by in vitro H2O2 treatment. Cells were exposed for 12-24 and 48h at treatment with extracts and then senescence-induced. ROS production was then determined. The real-time PCR was performed to evaluate the expression of inflammatory cytokines and sirtuin-dependent epigenetic changes, as well the modifications in terms of stem cell pluripotency. The β-galactosidase assay was conducted to analyze stem cell senescence after treatment. Our results show that industrial myrtle byproducts retain a high antioxidant and antisenescence activity, protecting cells from oxidative stress damages. The results obtained suggest that residues from myrtle liqueur production could be used as resource in formulation of food supplements or pharmaceutical preparations with antioxidant, antiaging, and anti-inflammatory activity