No abstract

This study aimed to evaluate the toxicological effects of oral intake of Zinc oxide nanoparticles (ZnO NPs) on the structure of thymus and spleen. Twenty-four young male Wistar albino rats were assigned into two groups: group I (control) and group II (ZnO NPs treated group).The thymus and spleen were analyzed biochemically, histopathologically and immunohistochemically. After ZnO NPs intake, hematologically, the total leucocytic count was significantly increased while the RBCs and platelets counts and Hb % were significantly decreased. Biochemically, a significant decrease in serum total antioxidant capacity and anti-inflammatory cytokines including interleukin 4 and 10 (IL-4 and IL-10) levels was noted. While a significant increase in splenic and thymic malondialdehyde (MDA) and DNA shearing, as well as the studied proinflammatory cytokines; IL-1β, tumor necrotic factor (TNF-α) and interferon (INF-γ) levels was detected. Notably, we noted upregulation of the immunomodulatory [CD3, CD11b, heme oxygenase (HO-1)] and the inflammatory [toll-like receptor 4 and 6 (TLR4 and TLR6)] genes. Histopathologically, degenerative changes were detected in thymus and spleen of ZnO NPs treated group. While the immunohistochemical analysis of the ZnO NPs treated group revealed a decrease in the number of cells expressed positive reactions of anti-PCNA and an increase in the number of cells expressed positive reaction of anti-p53 in the thymus and spleen. In conclusion, ZnO NPs induced obvious immunotoxicity in the thymus and spleen, where oxidative/inflammatory pathway may be the potential mechanism underlying this immunotoxicity. © 2017 IUBMB Life, 69(7):528-539, 2017.

We performed this study to understand the effect of human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) on the submandibular gland after bilateral ovariectomy. For this, 21 adult female rats were distributed equally among 3 groups: the sham-operated group (SHAM); the ovariectomized group (OVX); and the OVX group that received repeated intravenous injections of the hUCB-MSCs (OVX + hUCB-MSCs). We used reverse transcription - PCR to analyze for the gene expression of AQPs 3, 4, 5, and BMP-6. The cellular localization and expression of human CD105, human CD34, proliferating nuclear antigen (PCNA), single-stranded DNA (ss-DNA), caspase 3, AQP1, and α smooth muscle actin (α-SMA) were determined immunohistochemically. In the OVX group, a significant decrease in the gene expression of AQP3, AQP4, and BMP6, as well as the acinar area % was detected, while area % of granular convoluted tubules (GCTs) showed a significant increase. A significant decrease in area % staining positively for AQP1 and α-SMA was noted. An obvious improvement in the structure of the submandibular gland was demonstrated in the group injected with hUCB-MSCs, as well as a significant increase in the gene expression of AQP3, AQP4, and BMP6. The acinar and GCT area %, as well as the different measured markers, were relatively normal. This demonstrates that E2-deficiency induces structural changes to the submandibular gland. Moreover, a definite amelioration of the structure and function of the submandibular gland was detected after the administration of hUCB-MSCs.

We induced hypothyroidism (HT) in male rats through chronic oral administration of carbimazole and then tested whether an i.v. injection of rat bone marrow-derived mesenchymal stem cells (BM-MSCs) could ameliorate the HT-induced changes in pancreatic structure and function. The thyroid and pancreatic function tests, as well as total antioxidant capacity (TAC) and malondialdehyde (MDA) were estimated. The pancreatic structure was evaluated by hematoxylin and eosin (H&E) stain. Insulin protein and cleaved caspase-3 were detected immunohistochemically. The degree of apoptosis was assessed by TUNEL assay. The morphometric measurements were done by an image analyzer system and the obtained data were statistically analyzed. HT rats showed hyperglycemia associated with insulin deficiency, decreased TAC and increased MDA levels. H&E-stained sections showed that the pancreatic septa were infiltrated with acidophilic material. Some acini were vacuolated while others showed depleted acidophilia and dilated lumina. Spindle-shaped cells were accumulated within deformed islets in HT rats. The positive reaction with anti-cleaved caspase-3 was exclusively noted in the cytoplasm of islet cells with no immunostaining reaction in the acinar and ductal cells, whereas the positively stained nuclei with TUNEL were demonstrated in the islet and acinar cells. A significant increase in the apoptotic index % of both markers was detected. Injection of BM-MSCs in HT rats restored all biochemical indicators of disturbed pancreatic function to normal level and improved pancreatic structure, resulting in a clear septa and normal appearance of acini and islets. In conclusion, many of the significant structural and func tional pancreatic alterations detected in HT rats were ameliorated after the injection of BM-MSCs. These data demonstrate the ability of BM-MSCs to repair pancreatic disturbances. Further studies on humans are necessary to determine the potential clinical applications of BM-MSCs.

Background: Despite the fact that the exact architecture and orientation of left ventricular myocardial fibers are critical to cardiac functions either in health or disease, it is still debated. Aim of the work: Histological demonstration of the transverse alignment of the myofibers making the left ventricular mass was applied to validate different anatomical speculations of cardiac myofibers organization; mainly Streeter's conjecture and the ventricular myocardial band model of Torrent-Guasp. Material and methods: Six healthy adult male C57BL/6N mice were utilized. Their hearts were separated into atria and ventricles. Then, both ventricles were divided into four levels [base, upper mid, lower mid and apex]. Paraffin step-serial transverse sections were stained with H&E and Masson's trichrome stains. Morphometrical measurements of the thickness of the anterior, posterior, and lateral walls of the left ventricle (LV) as well as the inter-ventricular septal wall were realized with ImageJ software. For data analyses among the four levels of LV, Scheffé's method was applied for multiple comparisons when a significant difference was observed by Kruskal-Wallis test (p<0.05). Results: Examination of the LV from its base to its apex revealed obvious changes in the thickness of its walls and inter-ventricular septum as well as in its cavity shape. Interestingly, the myocardial fibers showed different running patterns [longitudinal, oblique and circular] among different levels as well as within the same level from sub-epicardial to the endocardial region. Throughout all levels, the subepicardial myofibers showed longitudinal orientation while that of the intermediate wall revealed either oblique [in upper mid-level] or circular orientations in other levels. The sub-endocardial fibers were mostly longitudinal with the presence of some circular fibers in the base and upper-mid regions. Masson's trichrome sections revealed a trivial amount of collagen fibers just around each individual myocyte without any bundle formation. Conclusion:The presence of different running patterns of the myocardial fibers among different levels of LV as well as within the same level indicates multiple rolling of the myocardial fibers. Thus, we suggested that the band model by Torrent-Guasp accounts for the patterns of myocardial fiber architecture forming the left ventricle.