scholarly journals Interplay Between Iron Overload and Osteoarthritis: Clinical Significance and Cellular Mechanisms

Author(s):  
Chenhui Cai ◽  
Wenhui Hu ◽  
Tongwei Chu

There are multiple diseases or conditions such as hereditary hemochromatosis, hemophilia, thalassemia, sickle cell disease, aging, and estrogen deficiency that can cause iron overload in the human body. These diseases or conditions are frequently associated with osteoarthritic phenotypes, such as progressive cartilage degradation, alterations in the microarchitecture and biomechanics of the subchondral bone, persistent joint inflammation, proliferative synovitis, and synovial pannus. Growing evidences suggest that the conditions of pathological iron overload are associated with these osteoarthritic phenotypes. Osteoarthritis (OA) is an important complication in patients suffering from iron overload-related diseases and conditions. This review aims to summarize the findings and observations made in the field of iron overload-related OA while conducting clinical and basic research works. OA is a whole-joint disease that affects the articular cartilage lining surfaces of bones, subchondral bones, and synovial tissues in the joint cavity. Chondrocytes, osteoclasts, osteoblasts, and synovial-derived cells are involved in the disease. In this review, we will elucidate the cellular and molecular mechanisms associated with iron overload and the negative influence that iron overload has on joint homeostasis. The promising value of interrupting the pathologic effects of iron overload is also well discussed for the development of improved therapeutics that can be used in the field of OA.

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 175-175
Author(s):  
Sandro Altamura ◽  
Hermann Josef Gröne ◽  
Regina Kessler ◽  
Bruno Galy ◽  
Matthias W. Hentze ◽  
...  

Abstract Systemic iron levels are tightly controlled by the hepatic hormone hepcidin in response to iron availability, inflammation, hypoxia or the iron demand for erythropoiesis. Hepcidin binds to the iron export protein ferroportin (FPN1) to regulate iron release from exporting cells. A mutation of cysteine 326 (C326S) of FPN1 was reported in a patient with non−classical ferroportin disease (Sham et al, 2005) and shown to abrogate hepcidin binding in vitro (Fernandes et al, 2009). To study consequences of the disruption of the hepcidin−ferroportin interaction in vivo, we generated the first knock−in mouse model of C326S non−classical ferroportin disease. Mice with either heterozygous or homozygous C326S FPN alleles are viable and fertile. At 8−weeks of age both heterozygous and homozygous mice show profoundly increased transferrin saturation and serum ferritin levels as well as hepatic iron overload. Histological analysis by Perl’s Prussian blue staining revealed that hepatic iron accumulation is restricted to hepatocytes and that Kupffer cells are spared of iron. In addition, splenic macrophages and duodenal enterocytes are iron−depleted. Macroscopically, C326S homozygous mice show progressive, brown discoloration of the pancreas that correlates with profound iron deposition. Histological analysis reveals that iron localizes exclusively to the exocrine pancreas sparing the islets of Langerhans. Consistently, C326S homozygous mice do not show any signs of diabetes. Pancreatic iron accumulation is closely associated with increased reactive oxygen species (ROS), degeneration of exocrine pancreatic cells, increased plasma lipase and exocrine pancreatic failure. Starting at the age of 33 weeks, pancreatic failure is accompanied by progressive wasting and death. We believe that C326S FPN mice represent the first example of fatal iron overload in an animal model, opening avenues to investigate the underlying molecular mechanisms. Sham R, Phatak PD, West C, et al. Autosomal dominant hereditary hemochromatosis associated with a novel ferroportin mutation and unique clinical features. Blood Cells Mol. Dis. 2005; 34:157−61. Fernandes A, Preza GC, Phung Y, et al. The molecular basis of hepcidin−resistant hereditary hemochromatosis. Blood. 2009;114:437−443. Disclosures: No relevant conflicts of interest to declare.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Nadezhda Fefelova ◽  
Suwakon Wongjaikam ◽  
Natthaphat Siri-Angkul ◽  
Judith Gwathmey ◽  
Nipon Chattipakorn ◽  
...  

Iron (Fe) plays essential roles in many physiological processes. Hereditary hemochromatosis and frequent blood transfusions result in iron overload (IO) and dysfunction of iron-deposited organs including the heart. Although IO-induced cardiomyopathy remains a significant clinical challenge, the underlying mechanism is not well defined. In the present study, we aim to assess the involvement of the mitochondrial Ca uniporter (mCU) in IO-induced cardiac contractile dysfunction and ferroptosis. In a chronic IO model, after receiving Fe (dextran, i.p. 0.6 mg/g, 3 days/wk) for 6 weeks, systolic function (LVEF and LVFS) was reduced in mCU +/+ (WT) compared to mCU -/- (mCU KO). This observation was confirmed in isolated ventricular myocytes where we similarly detected a significant decrease in cell shortening in WT, but not mCU KO myocytes. We found lower Fe levels in mitochondria from mCU KO myocytes compared to WT, while observing the same level of Fe deposition in heart tissue from both groups. The mitochondrial ROS level was lower in mCU KO myocytes vs. WT. Long term cardiac dysfunction may result in myocyte cell death, however, we did not detect apoptosis (TUNEL) in either mCU KO or in WT hearts with cardiac dysfunction after chronic IO. The lipid oxidation level was increased with Fe load suggesting ferroptosis may be involved in IO-induced cardiomyopathy, which was supported by the observation that administration of the selective ferroptosis inhibitor ferrostatin-1 reduced lipid oxidation (4-HNE) and maintained heart function. To further determine the role of mCU in IO-mediated ferroptosis in the heart, we used isolated myocytes from WT and mCU KO and conducted Live/Dead cell viability assays. While Fe (FAC, 0.1-5 mM) induced ferroptosis in a dose-dependent manner, it was prevented by ferrostatin-1 (10 μM), the Fe chelator 2,2'-bipyridyl (2 mM), and MitoTEMPO (5 μM), respectively. Fe-induced ferroptosis in mCU KO myocytes did not occur while the lipid oxidation level (Liperfluo) remained low. In conclusion, mitochondrial Fe uptake, presumably mediated by mCU, accounts for the molecular/cellular mechanisms for Fe-induced myocyte ferroptosis and cardiomyopathy. Cardiac-specific deficiency of mCU prevents the development of Fe induced cardiomyopathy.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 612-612
Author(s):  
Thomas Benedict Bartnikas ◽  
Sheryl Wildt ◽  
Amy Wineinger ◽  
Klaus Schmitz-Abe ◽  
Kyriacos Markianos ◽  
...  

Abstract Abstract 612 Sporadic iron overload has been reported previously in rats but the underlying cause has not been ascertained. In this study, phenotypic analysis of a subpopulation of Wistar rats designated Hsd:HHCL revealed a low incidence of histologically detected liver iron overload. One rat out of 132 screened animals exhibited liver iron accumulation in a predominantly periportal, hepatocellular distribution; this male rat expressed low RNA levels of the iron regulatory hormone hepcidin and low protein levels of transferrin receptor 2, a membrane protein essential for hepcidin expression in humans and mice and mutated in forms of hereditary hemochromatosis, a disease of excessive intestinal iron absorption and progressive tissue iron overload. Sequencing of the transferrin receptor 2 gene in the iron-overloaded rat revealed a novel Ala679Gly polymorphism affecting a highly conserved residue. Quantitative trait locus mapping revealed that a transferrin receptor 2 polymorphism correlated strongly with serum iron and transferrin saturations in male rats. Transfection of Tfr2 expression constructs into tissue culture cell lines revealed that the Gly679 Tfr2 variant is expressed at a lower level than the Ala679 variant. Selective breeding of rats carrying this polymorphism and characterization of iron metabolism in the resulting progeny indicated that homozygosity for the Ala679Gly allele leads to a hemochromatosis phenotype. The Hsd:HHCL rat is the first genetic rat model of hereditary hemochromatosis and may prove useful for understanding the molecular mechanisms underlying the regulation of iron metabolism and the pathogenesis of hereditary hemochromatosis. Disclosures: No relevant conflicts of interest to declare.


2020 ◽  
Vol 82 (6) ◽  
pp. 64-73
Author(s):  
O.H. Korotkyi ◽  
◽  
T.V. Luhovska ◽  
T.M. Serhiychuk ◽  
K.O. Dvorshchenko ◽  
...  

Osteoarthritis is a most widespread chronic degenerative joint disease that causes pain, cartilage deformation, and joint inflammation. Adverse alterations of intestinal microbiota like dysbiosis may lead to metabolic syndrome and inflammation, two important components of osteoarthritis progression. Aim. In this study we investigated the effect of chondroitin sulfate and probiotics on the gut microbiome in monoiodoacetate-induced osteoarthritis model in rats. Methods. The species and quantitative composition of feces were determined using diagnostic media with selective properties. Further identification of isolated microorganisms was carried out according to morphological, tinctorial, physiological and metabolic parameters. The results are presented in the form of lg CFU/g. Results. Induction of osteoarthritis caused significant increasing the number of opportunistic enterobacteria and lactose-negative Escherichia coli against the decreasing of lacto- and bifidobacteria that may indicate a dysbiotic condition. Coadministration of chondroitin sulfate and probiotic bacteria has led to improvement the quantitative composition of the gut microbiota in experimental animals, the numerous of Bifidobacterium, Lactobacillus were increasing against decreasing the quantitative composition of opportunistic microorganisms. Conclusions. Monoiodoacetate-induced osteoarthritis caused dysbiosis of gut in rat. We observed beneficial effect of combined administration of chondroitin sulfate and probiotics on gut microbiota composition in rats with experimental osteoarthritis. Thus, adding of supplements like probiotics to standard treatment of osteoarthritis may have potentials to prevent and treat this disease.


2020 ◽  
Vol 15 (7) ◽  
pp. 559-569 ◽  
Author(s):  
Zhen Chang ◽  
Youhan Wang ◽  
Chang Liu ◽  
Wanli Smith ◽  
Lingbo Kong

Macrophages M2 polarization have been taken as an anti-inflammatory progression during inflammation. Natural plant-derived products, with potential therapeutic and preventive activities against inflammatory diseases, have received increasing attention in recent years because of their whole regulative effects and specific pharmacological activities. However, the molecular mechanisms about how different kinds of natural compounds regulate macrophages polarization still unclear. Therefore, in the current review, we summarized the detailed research progress on the active compounds derived from herbal plants with regulating effects on macrophages, especially M2 polarization. These natural occurring compounds including flavonoids, terpenoids, glycosides, lignans, coumarins, alkaloids, polyphenols and quinones. In addition, we extensively discussed the cellular mechanisms underlying the M2 polarization for each compound, which could provide potential therapeutic strategies aiming macrophages M2 polarization.


2019 ◽  
Vol 104 (11) ◽  
pp. 5372-5381 ◽  
Author(s):  
Nigel K Stepto ◽  
Alba Moreno-Asso ◽  
Luke C McIlvenna ◽  
Kirsty A Walters ◽  
Raymond J Rodgers

Abstract Context Polycystic ovary syndrome (PCOS) is a common endocrine condition affecting 8% to 13% of women across the lifespan. PCOS affects reproductive, metabolic, and mental health, generating a considerable health burden. Advances in treatment of women with PCOS has been hampered by evolving diagnostic criteria and poor recognition by clinicians. This has resulted in limited clinical and basic research. In this study, we provide insights into the current and future research on the metabolic features of PCOS, specifically as they relate to PCOS-specific insulin resistance (IR), that may affect the most metabolically active tissue, skeletal muscle. Current Knowledge PCOS is a highly heritable condition, yet it is phenotypically heterogeneous in both reproductive and metabolic features. Human studies thus far have not identified molecular mechanisms of PCOS-specific IR in skeletal muscle. However, recent research has provided new insights that implicate energy-sensing pathways regulated via epigenomic and resultant transcriptomic changes. Animal models, while in existence, have been underused in exploring molecular mechanisms of IR in PCOS and specifically in skeletal muscle. Future Directions Based on the latest evidence synthesis and technologies, researchers exploring molecular mechanisms of IR in PCOS, specifically in muscle, will likely need to generate new hypothesis to be tested in human and animal studies. Conclusion Investigations to elucidate the molecular mechanisms driving IR in PCOS are in their early stages, yet remarkable advances have been made in skeletal muscle. Overall, investigations have thus far created more questions than answers, which provide new opportunities to study complex endocrine conditions.


2021 ◽  
Vol 10 (8) ◽  
pp. 1555
Author(s):  
Ágoston Patthy ◽  
János Murai ◽  
János Hanics ◽  
Anna Pintér ◽  
Péter Zahola ◽  
...  

Alzheimer’s disease (AD) is a devastating neurodegenerative disorder as yet without effective therapy. Symptoms of this disorder typically reflect cortical malfunction with local neurohistopathology, which biased investigators to search for focal triggers and molecular mechanisms. Cortex, however, receives massive afferents from caudal brain structures, which do not only convey specific information but powerfully tune ensemble activity. Moreover, there is evidence that the start of AD is subcortical. The brainstem harbors monoamine systems, which establish a dense innervation in both allo- and neocortex. Monoaminergic synapses can co-release neuropeptides either by precisely terminating on cortical neurons or, when being “en passant”, can instigate local volume transmission. Especially due to its early damage, malfunction of the ascending monoaminergic system emerges as an early sign and possible trigger of AD. This review summarizes the involvement and cascaded impairment of brainstem monoaminergic neurons in AD and discusses cellular mechanisms that lead to their dysfunction. We highlight the significance and therapeutic challenges of transmitter co-release in ascending activating system, describe the role and changes of local connections and distant afferents of brainstem nuclei in AD, and summon the rapidly increasing diagnostic window during the last few years.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yu Wu ◽  
Xianjing Hu ◽  
Liyan Song ◽  
Jianhua Zhu ◽  
Rongmin Yu

Inflammation is known to be closely associated with the development of cancer. The study was launched in human cervical cancer HeLa cells to investigate the antitumor and anti-inflammatory effects of P2, a marine polypeptide fraction from an important fishery resourceArca subcrenata. The basic research showed that P2 could suppress the production of nitric oxide in LPS-induced RAW264.7 macrophage cells as well as the secretion of inflammatory cytokines IL-6 and TNF-αin human cervical cancer HeLa cells. For the molecular mechanisms, P2 was shown to downregulate the gene expression of proinflammatory cytokines IL-6 and IL-8 and to inhibit the COX-2 and iNOS-related pathways in HeLa cells. In consequence, P2 might inhibit tumor development by blocking the interaction between tumor microenvironment and proinflammatory mediators. All findings indicate that P2 possesses the potential to be developed as a novel agent for cancer therapy.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Liang Guo ◽  
Jun-mei Xu ◽  
Lei Liu ◽  
Su-mei Liu ◽  
Rong Zhu

Pulmonary fibrosis is a severe disease that contributes to the morbidity and mortality of a number of lung diseases. However, the molecular and cellular mechanisms leading to lung fibrosis are poorly understood. This study investigated the roles of epithelial-mesenchymal transition (EMT) and the associated molecular mechanisms in bleomycin-induced lung fibrosis. The bleomycin-induced fibrosis animal model was established by intratracheal injection of a single dose of bleomycin. Protein expression was measured by Western blot, immunohistochemistry, and immunofluorescence. Typical lesions of lung fibrosis were observed 1 week after bleomycin injection. A progressive increase in MMP-2, S100A4,α-SMA, HIF-1α, ZEB1, CD44, phospho-p44/42 (p-p44/42), and phospho-p38 MAPK (p-p38) protein levels as well as activation of EMT was observed in the lung tissues of bleomycin mice. Hypoxia increased HIF-1αand ZEB1 expression and activated EMT in H358 cells. Also, continuous incubation of cells under mild hypoxic conditions increased CD44, p-p44/42, and p-p38 protein levels in H358 cells, which correlated with the increase in S100A4 expression. In conclusion, bleomycin induces progressive lung fibrosis, which may be associated with activation of EMT. The fibrosis-induced hypoxia may further activate EMT in distal alveoli through a hypoxia-HIF-1α-ZEB1 pathway and promote the differentiation of lung epithelial cells into fibroblasts through phosphorylation of p38 MAPK and Erk1/2 proteins.


2013 ◽  
Vol 93 (4) ◽  
pp. 1743-1802 ◽  
Author(s):  
Jean-Sébastien Silvestre ◽  
David M. Smadja ◽  
Bernard I. Lévy

After the onset of ischemia, cardiac or skeletal muscle undergoes a continuum of molecular, cellular, and extracellular responses that determine the function and the remodeling of the ischemic tissue. Hypoxia-related pathways, immunoinflammatory balance, circulating or local vascular progenitor cells, as well as changes in hemodynamical forces within vascular wall trigger all the processes regulating vascular homeostasis, including vasculogenesis, angiogenesis, arteriogenesis, and collateral growth, which act in concert to establish a functional vascular network in ischemic zones. In patients with ischemic diseases, most of the cellular (mainly those involving bone marrow-derived cells and local stem/progenitor cells) and molecular mechanisms involved in the activation of vessel growth and vascular remodeling are markedly impaired by the deleterious microenvironment characterized by fibrosis, inflammation, hypoperfusion, and inhibition of endogenous angiogenic and regenerative programs. Furthermore, cardiovascular risk factors, including diabetes, hypercholesterolemia, hypertension, diabetes, and aging, constitute a deleterious macroenvironment that participates to the abrogation of postischemic revascularization and tissue regeneration observed in these patient populations. Thus stimulation of vessel growth and/or remodeling has emerged as a new therapeutic option in patients with ischemic diseases. Many strategies of therapeutic revascularization, based on the administration of growth factors or stem/progenitor cells from diverse sources, have been proposed and are currently tested in patients with peripheral arterial disease or cardiac diseases. This review provides an overview from our current knowledge regarding molecular and cellular mechanisms involved in postischemic revascularization, as well as advances in the clinical application of such strategies of therapeutic revascularization.


Sign in / Sign up

Export Citation Format

Share Document