Siderin

Preliminary study to investigate the distribution and effects of certain metals after inhalation of welding fumes in mice.[Pubmed:35212899]

Environ Sci Pollut Res Int. 2022 Jul;29(32):49147-49160.

The most important welding processes used are the gas metal arc (GMA) welding, the tungsten inert gas (TIG) welding, and the manual metal arc (MMA) welding processes. The goal of our investigation was to monitor the distribution of iron (Fe), manganese (Mn), calcium (Ca), and magnesium (Mg) in the lung, spleen, liver, and kidney of mice after inhalation exposure of different welding methods using different steel base materials. The treatment groups were the following: MMA-mild steel, MMA-molybdenum-manganese (MoMn) alloy, TIG-mild steel, and TIG-stainless steel. The samples were taken 24 and 96 h after the treatments. Most importantly, it was found that the Mn concentration in the lung' samples of the MMA-mild steel and the MMA-MoMn groups was increased extremely at both sampling times and in the spleen' samples also. In the TIG groups, the rise of the Mn concentration was only considerable in the lungs and spleens at 24 h, and emerged concentration was found in the liver in 96 h samples. Histopathology demonstrated emerged Siderin content in the spleens of the treated animals and in Siderin filled macrophages in the lungs mostly in all treated groups. Traces of high-level glycogen retention was found in the MMA groups at both sampling times. Similar glycogen retention in TIG-Ms and TIG stainless group's liver samples and emerged number of vacuoles, especially in the hepatocytes of the TIG-stainless steel 96 h group were also found. The mentioned results raise the consequence that there is a considerable difference in the kinetics of the Mn distribution between the MMA- and the TIG-fume-treated groups. Hence, the result suggests that manganese has a particle-size-dependent toxico-kinetics property. The anomaly of the glycogen metabolism indicates the systemic effect of the welding fumes. Also, the numerous vacuoles mentioned above show a possible liver-specific adverse effect of some components of the TIG-stainless steel welding fumes.

Natural compounds with cell growth inhibitory activity in human tumor cell lines.[Pubmed:23438826]

Anticancer Agents Med Chem. 2013 Dec;13(10):1582-9.

Twenty six compounds (coumarins, flavonoids and alkaloids) were evaluated for their ability to inhibit the growth of three human tumor cell lines: breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and melanoma (A375-C5). Three of them [3-hydroxyflavone (6), 2'-hydroxy-3,4,4',5,6'-pentamethoxychalcone (11), Siderin (20)] were very potent in inhibiting all human tumor cell lines tested. The structure / activity relationship is discussed.

Bioactive anthraquinones from endophytic fungus Aspergillus versicolor isolated from red sea algae.[Pubmed:23139125]

Arch Pharm Res. 2012 Oct;35(10):1749-56.

The marine fungus Aspergillus versicolor was isolated from the inner tissue of the Red Sea green alga Halimeda opuntia. The fungus was identified by its morphology and 18s rDNA. Cultivation of this fungal strain led to a new metabolite named isorhodoptilometrin-1-methyl ether (1) along with the known compounds emodin (2), 1-methyl emodin (3), evariquinone (4), 7-hydroxyemodin 6,8-methyl ether (5), Siderin (6), arugosin C (7), and variculanol (8). The structures were elucidated on the basis of NMR spectroscopic analysis and mass spectrometry. The biological properties of ethyl acetate extract and compounds 1-3 and 6-8 were explored for antimicrobial activity, anti-cancer activity and inhibition of Hepatitis C virus (HCV) protease.

[Chemical constituents of rhizoma imperatae and their anti-complementary activity].[Pubmed:21548362]

Zhong Yao Cai. 2010 Dec;33(12):1871-4.

OBJECTIVE: To study the chemical constituents of Rhizoma Imperatae and their anti-complementary activity. METHODS: By the hemolysis test, the petroleum extraction, ethyl acetate extraction, n-butanol extraction and the water extraction was tested for anti-complementary activity. Compounds were isolated and purified by silica gel column chromatography, Sephadex LH-20 and reversed-phase column chromatography. The structures were identified by the various spectroscopic data of ESI-MS, 1H-NMR, 13C-NMR. The compounds were evaluated for anti-complementary activity in vitro. RESULTS: The petroleum extraction, ethyl acetate extraction showed significant anti-complementary activity. Ten compounds were isolated from the petroleum and EtOAc soluble fractions and identified as cylindrin (1), arundoin (2), friedelin (3), beta-sitosterol (4), Siderin (5), ethyl p-hydroxybenzoate (6), 5-methoxyflavone (7), vanillic acid (8), trans-p-coumaric acid (9), 5-hydroxymethylfurfural (10). CONCLUSION: Compounds 6, 7, 8, and 10 are isolated from the genus for the first time, and compounds 3, 8 and 9 inhibited the complement system towards the classical pathway.

Polyphasic taxonomy of Aspergillus section Sparsi.[Pubmed:22679579]

IMA Fungus. 2010 Dec;1(2):187-95.

Aspergillus section Sparsi includes species which have large globose conidial heads with colours ranging from light grey to olive-buff. In this study, we examined isolates of species tentatively assigned to section Sparsi using a polyphasic approach. The characters examined include sequence analysis of partial beta-tubulin, calmodulin and ITS sequences of the isolates, morphological and physiological tests, and examination of the extrolite profiles. Our data indicate that the revised section Sparsi includes 10 species: A. anthodesmis, A. biplanus, A. conjunctus, A. diversus, A. funiculosus, A. implicatus, A. panamensis, A. quitensis, A. sparsus, and the new taxon A. haitiensis. The recently described A. quitensis and A. ecuadorensis are synonyms of A. amazonicus based on both molecular and physiological data. The white-spored species A. implicatus has also been found to belong to this section. Aspergillus haitiensis sp. nov. is characterised by whitish colonies becoming reddish brown due to the production of conidial heads, and dark coloured smooth stipes. The taxon produces gregatins, Siderin and several unknown but characteristic metabolites.

Four new species of Emericella from the Mediterranean region of Europe.[Pubmed:18959164]

Mycologia. 2008 Sep-Oct;100(5):779-95.

Four new species of Emericella, E. discophora, E. filifera, E. olivicola and E. stella-maris, are proposed. Their new taxonomic status was determined applying a polyphasic taxonomic approach using phenotypic (morphology and extrolite profiles) and molecular (sequences of ITS, beta-tubulin and calmodulin genes) characters. Ascospores of E. stella-maris and E. olivicola have star-shape equatorial crests, those of E. filifera form long appendages that emerge radially from narrow stellate crests and those of E. discophora produce wide and entire, nonstellate equatorial crests. E. stella-maris originated from leaf litter in Tunisia and E. filifera from raisins in Argentina, and both of them also were found in hypersaline water of a saltern in Slovenia. E. olivicola was isolated from olives in Italy and E. discophora from soil in Spain. All listed species possess distinct extrolite profiles: E. stella-maris produced arugosin E, shamixanthone and the yet unelucidated metabolites glia 1-3; E. filifera produced shamixanthone and varitriols; E. discophora produced sterigmatocystin and versicolorins; E. olivicola produced numerous extrolites such as arugosin E, Siderin, shamixanthone, sterigmatocystin, terrein, varitriols and aflatoxin B1, of which the latter was detected only in one of the two strains.

Siderin from Toona ciliata (Meliaceae) as photosystem II inhibitor on spinach thylakoids.[Pubmed:17568558]

Arch Biochem Biophys. 2007 Sep 1;465(1):38-43.

Four natural products were isolated from plants of the Rutaceae and Meliaceae families and their effect on photosynthesis was tested. Siderin (1) inhibited both ATP synthesis and electron flow (basal, phosphorylating, and uncoupled) from water to methylviologen (MV); therefore, it acts as Hill reaction inhibitor in freshly lysed spinach thylakoids. Natural products 2-4 were inactive. Secondary metabolite 1 did not inhibit PSI electron transport. It inhibits partial reactions of PSII electron flow from water to 2,6-dichlorophenol indophenol (DCPIP), from water to sodium silicomolybdate, and partially inhibits electron flow from diphenylcarbazid (DPC) to DCPIP. These results established that the site of inhibition of 1 was at the donor and acceptor sides of PSII, between P(680) and Q(A). Chlorophyll a fluorescence measurements confirmed the behavior of the Toona ciliate coumarin 1 as P(680) to Q(A) inhibitor by the creation of silent centers. May be this is the mechanisms of action of 1 and is the way in which it develops a phytotoxic activity against photosynthesis.

Regio- and stereoselective intermolecular oxidative phenol coupling in kotanin biosynthesis by Aspergillus niger.[Pubmed:17315249]

Chembiochem. 2007 Mar 26;8(5):521-9.

The intermolecular, regio- and stereoselective phenol coupling for the biosynthesis of the bicoumarin kotanin in Aspergillus niger has been investigated. Feeding experiments with singly and doubly (13)C-labeled monomeric precursors clearly proved that it is not the coumarin Siderin but its hydroxy derivative, demethylSiderin, that undergoes phenol coupling. However, Siderin is demethylated regioselectively to demethylSiderin and it is the latter that is coupled to the corresponding dehydrodimer, orlandin. The product is subsequently O-methylated in a stepwise fashion to demethylkotanin and kotanin. Crude extracts were analysed by HPLC with chemically synthesized bicoumarins as reference compounds. This and a stereochemical analysis of the isolated bicoumarins revealed that A. niger produces exclusively the (P)-atropisomers of the three 8,8'-bicoumarins, kotanin, demethylkotanin, and orlandin. The absence of other monomeric or dimeric coumarins strongly suggests an intermolecular, regio- and stereoselective mode for the phenol-coupling step.

Ascorbic acid deficiency, iron overload and alcohol abuse underlie the severe osteoporosis in black African patients with hip fractures--a bone histomorphometric study.[Pubmed:15549637]

Calcif Tissue Int. 2005 Feb;76(2):79-89.

Osteoporosis and femoral neck fractures (FNF) are uncommon in black Africans although osteoporosis accompanying iron overload (from traditional beer brewed in iron containers) associated with ascorbic acid deficiency (oxidative catabolism by iron) has been described from sub-Saharan Africa. This study describes histomorphometric findings of iliac crest bone biopsies and serum biochemical markers of iron overload and of alcohol abuse and ascorbic acid levels in 50 black patients with FNFs (29 M, 21 F), age 62 years (40-95) years (median [min-max]), and in age- and gender-matched black controls. We found evidence of iron overload in 88% of patients and elevated markers of alcohol abuse in 72%. Significant correlations between markers of iron overload and of alcohol abuse reflect a close association between the two toxins. Patients had higher levels of iron markers, i.e., Siderin deposits in bone marrow (P < 0.0001), chemical non-heme bone iron (P = 0.012), and serum ferritin (P = 0.017) than controls did. Leukocyte ascorbic acid levels were lower (P = 0.0008) than in controls. The alcohol marker mean red blood cell volume was elevated (P = 0.002) but not liver enzymes or uric acid. Bone volume, trabecular thickness, and trabecular number were lower, and trabecular separation was greater in patients than in controls, all at P < 0.0005; volume, surface, and thickness of osteoid were lower and eroded surface was greater, all at P < 0.0001. There was no osteomalacia. Ascorbic acid deficiency accounted significantly for decrease in bone volume and trabecular number, and increase in trabecular separation, osteoid surface, and eroded surface; iron overload accounted for a reduction in mineral apposition rate. Alcohol markers correlated negatively with osteoblast surface and positively with eroded surface. Relative to reported data in white FNF patients, the osteoporosis was more severe, showed lower osteoid variables and greater eroded surface; FNFs occurred 12 years earlier and were more common among men. We conclude that the osteoporosis underlying FNFs in black Africans is severe, with marked uncoupling of resorption and formation in favor of resorption. All three factors--ascorbic acid deficiency, iron overload, and alcohol abuse--contributed to the osteoporosis, in that order.

Antimicrobial activity of Toona ciliata and Amoora rohituka.[Pubmed:12628414]

Fitoterapia. 2003 Feb;74(1-2):155-8.

The extracts of two Bangladeshi medicinal plants, Toona ciliata (stem bark) and Amoora rohituka (stem bark), along with Siderin, a major coumarin from T. ciliata, exhibited significant in vitro antibacterial activity. The extracts also demonstrated mild antifungal effect.

Vestibular schwannomas: correlations between magnetic resonance imaging and histopathologic appearance.[Pubmed:11314722]

Otol Neurotol. 2001 Jan;22(1):79-86.

BACKGROUND: The indication for surgery of vestibular schwannomas (VS) remains controversial and depends on several factors. The ability to predict their patterns of growth would allow better surgical planning. This growth may depend on tumoral proliferation but also depends on dystrophic changes. OBJECTIVE: The aim of this study was to evaluate the role of magnetic resonance imaging (MRI) in predicting the evolution of VS. For this purpose, the authors attempted (1) to compare the MRI appearance of VS with its histopathologic features, (2) to correlate the MRI appearance of VS and its histopathologic features with its size, and (3) to evaluate the index of proliferation (IP) of each VS. PATIENTS AND METHODS: Thirty VS were studied with MRI before surgery. The VS were measured and classified as homogeneous, heterogeneous, and cystic. After surgery, IP was evaluated with immunohistochemical study using MIB-1 monoclonal antibody, and compared with tumor size. Pathologic studies evaluated the prevalence of Antoni type A and type B tissue, the amount of fibrosis, and the presence of Siderin-loaded macrophages, xanthomatous cells, and cysts. RESULTS: The IP was low (0.2%-2.2%) and was not correlated with VS size. On MRI, 13 VS were homogeneous, 12 heterogeneous, and 5 cystic. The 13 homogeneous VS were smaller and were predominantly made of Antoni type A tissue. The 12 heterogeneous and 5 cystic VS were larger and were predominantly made of Antoni type B/mixed tissue. Heterogeneous and cystic VS showed significantly more hemoSiderin deposits. There was a significant relation between the amount of hemoSiderin deposits and the mean size of VS. Microscopic cysts were observed only in VS with cystic MRI appearance. Fibrosis was present in all tumors regardless of their size and MRI appearance. CONCLUSION: A heterogeneous MRI aspect (correlated with larger mean size) not only is related to the ratio of type A to type B tissue but also is caused by other pathologic changes, mainly hemoSiderin deposits and cystic formation. Increasing tumor size probably depends less on IP than on dystrophic changes (hemoSiderin, cysts) and/or on the presence of type B tissue.

[Sideroelastosis of pulmonary vessels after welder dust exposure].[Pubmed:10900615]

Pathologe. 2000 May;21(3):229-33.

Sideroelastosis pulmonum was first described by Ceelen (1931) and Gellerstedt (1939), mentioning an idiopathic type, but also vascular alterations in chronic pulmonary congestion. We analysed the question wether secondary sideroelastosis can be demonstrated also in lungs after previous welder dust exposure. Lung samples of 43 patients and deceased with various exposure periods to welder dust were investigated. On each sample, light microscopical, scan electron microscopical and energy dispersive x-ray micro analyses (EDX) were performed. In six samples (14%) vascular alterations in the area of denaturated elastic fibres with siderophilic "impregnation" were seen, corresponding to the features described by von Ceelen and Gellerstedt. Giant cell or granulomatous reactions, however, were present only in exceptional cases. This phenomenon was seen mostly in cases of marked local Siderin deposits and reactive fibrosis. Using EDX, a number of metals characteristic for welder dust (Al, Ti, Cr, Ni) as well as iron were found in siderophages. No other metal than iron was detected in siderophilic elastic fibres using EDX. Causal pathogenetically, a correlation between increased iron uptake connected with welding particles and sideroelastosis of the vessel walls has to be established. However, in formal pathogenesis, other factors such as local perfusion disturbances due to fibrotic processes after exposure to harmful substances must be taken into consideration.

How clean is a mini-pig?--Impressions and suggestions of a pathologist working in the field of toxicology.[Pubmed:9249856]

Pharmacol Toxicol. 1997;80 Suppl 2:16-22.

Gross and histopathological investigations of more than 100 minipigs revealed: 1. Findings due to repeated blood sampling. For anatomical reasons the thyroid gland of pigs can be injured during blood sampling. Histopathological investigation of thyroid glands often revealed inflammatory and reparative fibrotic changes of this organ. Depending on the grade of damage, thyroid hormone levels may vary. To avoid misinterpretation of results, most careful blood sampling by experienced personnel is recommended. 2. Findings due to viral, bacterial and parasitic infections. These concerned mainly the lungs which often showed pneumonic alterations. In case of parasitic invasion, the skeletal muscles may reveal degenerative changes due to sarcosporidia (re-) infection. Therefore, optimal hygienic conditions, e.g. during blood sampling, and continuing health monitoring are recommended. 3. Findings due to preventive iron administration. Months after preventive iron-dextran administration at the breeding station, histopathological examination revealed Siderin accumulation in a number of organs, namely in the cells of the mononuclear phagocytic system in liver and kidneys. As a unique finding an intraglomerular Siderin deposition in the mesangial cells with subsequent glomerulosclerosis in certain glomeruli was observed.

[Hepatic neoductules].[Pubmed:8600693]

Verh Dtsch Ges Pathol. 1995;79:36-46.

Proliferation of preexisting bile ducts, ductular metaplasia of hepatocytes and proliferation and differentiation of liver stem cells are discussed in the pathogenesis of neoductular structures in the liver. Under the condition of experimental bile duct obstruction and in extrahepatic bile duct stenosis neoductular structures are first the result of proliferation and sprouting of preexisting ducts and cholangioles. Especially in later stages of cholestasis but also in other chronic progredient liver diseases such as chronic alcoholic liver disease and chronic active hepatitis periportal hepatocytes may show a phenotypic shift towards ductular epithelia. In postnatal liver diseases hepatocytes first express keratin 7 and later keratin 19 during ductular transdifferentiation. This is in contrast to embryonal cholangiogenesis. In alpha-1-antitrypsin-deficiency, hemochromatosis, Wilson's disease, and chronic active hepatitis B cellular deposites typically located in hepatocytes such as alpha-1-AT, Siderin, copper, HBs-Ag, and HBc-Ag can also be found in neoductular cells close to hepatocytes. These deposites seem to be retained during the ductular transdifferentiation of hepatocytes. Expression of bile duct-type integrin subtypes and TGF beta 1 in neoductular cells are involved in the changing parenchymal/mesenchymal interplay during neoductogenesis, resulting in periductular basal membrane and periductular fibrosis. In FNH the ductular transdifferentiation of hepatocytes is integrated in the histogenesis of micronodules and portal tract equivalents of these tumor-like lesions. Ductular structures in hepatoblastomas and especially in combined hepatocellular and cholangiocarcinomas (CHCC) may reflect the common embryologic derivation of hepatocytes and biliary epithelia. Non-neoplastic liver tissue in resection specimens of our CHCC showed a lower rate of cirrhosis, and a significantly higher Ki 67-LI of neoductular cells compared to liver tissue in resection specimens of HCC and liver metastases. 3 of 10 CHCC had developed in alpha-1-AT-deficiency, in which this protease-inhibitor was predominantly retained in periportal hepatocytes. These findings in non-neoplastic tumor-bearing liver tissue suggest that CHCC include a special histogenic type of primary liver carcinoma which in analogy to some experimental liver tumors might develop from periportal parenchymal cells.

Postpartum erythrophagocytosis, iron storage and iron secretion in the endometrium of the tree shrew (Tupaia) during pregnancy.[Pubmed:7928647]

J Anat. 1994 Jun;184 ( Pt 3)(Pt 3):597-606.

Tree shrews (Tupaia belangeri) develop a bidiscoid endotheliochorial placenta. In addition, histiotrophe secreted by uterine glands is absorbed by the paraplacental trophoblast. Histiotrophe which is rich in iron is necessary for erythropoiesis in the young embryo. This report is part of a study of the accumulation and metabolism of iron in the endometrium of precisely dated pregnant Tupaia belangeri by application of electron spectroscopy and histochemistry. In the endometrium of tree shrews which had been pregnant at least once, iron-laden granules were present in macrophages and secreting cells of uterine glands. Iron accumulated in the endometrium shortly after parturition, when macrophages phagocytosed erythrocytes at small haematomas 0.2-0.5 mm in diameter. These haematomas arose during parturition after bleeding into the uterine stroma when the placental discs were detached. At 24 h after parturition the following structural consequences of the erythrolysosomal breakdown of phagocytosed erythrocytes could be observed: free cytosolic Siderin granules, membrane-bound siderosomes, telolysosomes (some of which contained myelin figures or lipid droplets) and mixed telolysosomes (containing membranous stacks and Siderin granules). During the lysosomal degradation of phagocytosed erythrocytes, iron was transferred from haemoglobin into a different macromolecular compound. Electron energy loss spectra detected from inside siderosomes indicated an iron-oxygen compound, and high-power bright field electron micrographs of siderosomes demonstrated the ultrastructural pattern characteristic of ferritin. At about d 12 of a new pregnancy, macrophages containing siderosomes closely approached the bases of secreting cells of endometrial glands. This strongly suggests that iron is transferred from the macrophages to the glandular cells. Within the glandular cells, iron-rich histiotrophe was synthesised and released into the glandular lumen. Within the uterine cavity this histiotrophe was absorbed by the omphalopleure. We suggest that among eutherians, postpartum erythrophagocytosis, the transfer of iron from macrophages to uterine glands, and the paraplacental uptake of iron, represent an ancestral mechanism of iron supply to the embryo.