Therapeutic Potential of Bioactive Compounds in Honey for Treating Osteoarthritis.

Dysregulation of joint tissue homeostasis induces articular degenerative changes and musculoskeletal diseases such as osteoarthritis. This pathology represents the first cause of motor disability in individuals over 60 years of age, impacting their quality of life and the costs of health systems. Nowadays, pharmacological treatments for cartilage disease have failed to achieve full tissue regeneration, resulting in a functional loss of the joint; therefore, joint arthroplasty is the gold standard procedure to cure this pathology in severe cases of Osteoarthritis. A different treatment is the use of anti-inflammatory drugs which mitigate pain and inflammation in some degree, but without significant inhibition of disease progression. In this sense, new therapeutic alternatives based on natural compounds have been proposed to delay osteoarthritis progression, particularly those agents that regulate articular homeostasis. Preclinical studies have shown a therapeutic application of honey and its bioactive compounds, ranging from treating wounds, coughs, skin infections, and are also used as a biological stimulant by exerting antioxidant and anti-inflammatory properties. In this article, we reviewed the current medicinal applications of honey with particular emphasis on its use regulating articular homeostasis by inhibiting inflammation and oxidative stress.

tBHQ Induces a Hormetic Response That Protects L6 Myoblasts against the Toxic Effect of Palmitate.

Nutritional status, in particular overweight and obesity, as well as sedentarism and high-fat diet consumption, are important risk factors to develop chronic diseases, which have a higher impact on the elderly's health. Therefore, these nutritional problems have become a concern to human healthspan and longevity. The fatty acids obtained thru the diet or due to fatty acid synthesis during obesity accumulate within the body generating toxicity and cell death. Fat is not only stored in adipose tissue, but it can also be stored in skeletal muscle. Palmitic acid (PA) has been reported as one of the most important saturated free fatty acids; it is associated to chronic oxidative stress and increased mitochondrial ROS production causing cell death by apoptosis. In skeletal muscle, palmitate has been associated with various pathophysiological consequences, which lead to muscle deterioration during aging and obesity. Since molecules that modify redox state have been proven to prevent cellular damage by inducing a hormetic response, the aim of this study was to evaluate if tert-butylhydroquinone (tBHQ) could activate an antioxidant hormetic response that would be able to protect L6 myoblasts from palmitate toxic effect. Our results provide evidence that tBHQ is able to protect L6 myoblasts against the toxicity induced by sodium palmitate due to a synergistic activation of different signaling pathways such as Nrf2 and NF-κB.

HGF induces protective effects in α-naphthylisothiocyanate-induced intrahepatic cholestasis by counteracting oxidative stress.

Cholestasis is a clinical syndrome common to a large number of hepatopathies, in which either bile production or its transit through the biliary tract is impaired due to functional or obstructive causes; the consequent intracellular retention of toxic biliary constituents generates parenchyma damage, largely via oxidative stress-mediated mechanisms. Hepatocyte growth factor (HGF) and its receptor c-Met represent one of the main systems for liver repair damage and defense against hepatotoxic factors, leading to an antioxidant and repair response. In this study, we evaluated the capability of HGF to counteract the damage caused by the model cholestatic agent, α-naphthyl isothiocyanate (ANIT). HGF had clear anti-cholestatic effects, as apparent from the improvement in both bile flow and liver function test. Histology examination revealed a significant reduction of injured areas. HGF also preserved the tight-junctional structure. These anticholestatic effects were associated with the induction of basolateral efflux ABC transporters, which facilitates extrusion of toxic biliary compounds and its further alternative depuration via urine. The biliary epithelium seems to have been also preserved, as suggested by normalization in serum GGT levels, CFTR expression and cholangyocyte primary cilium structure our results clearly show for the first time that HGF protects the liver from a cholestatic injury.

Hepatocyte growth factor enhances the clearance of a multidrug-resistant Mycobacterium tuberculosis strain by high doses of conventional chemotherapy, preserving liver function.

Tuberculosis (TB) is one of the deadliest infectious diseases in humankind history. Although, drug sensible TB is slowly decreasing, at present the rise of TB cases produced by multidrug-resistant (MDR) and extensively drug-resistant strains is a big challenge. Thus, looking for new therapeutic options against these MDR strains is mandatory. In the present work, we studied, in BALB/c mice infected with MDR strain, the therapeutic effect of supra-pharmacological doses of the conventional primary antibiotics rifampicin and isoniazid (administrated by gavage or intratracheal routes), in combination with recombinant human hepatocyte growth factor (HGF). This high dose of antibiotics administered for 3 months, overcome the resistant threshold of the MDR strain producing a significant reduction of pulmonary bacillary loads but induced liver damage, which was totally prevented by the administration of HGF. To address the long-term efficiency of this combined treatment, groups of animals after 1 month of treatment termination were immunosuppressed by glucocorticoid administration and, after 1 month, mice were euthanized, and the bacillary load was determined in lungs. In comparison with animals treated only with a high dose of antibiotics, animals that received the combined treatment showed significantly lower bacterial burdens. Thus, treatment of MDR-TB with very high doses of primary antibiotics particularly administrated by aerial route can produce a very good therapeutic effect, and its hepatic toxicity can be prevented by the administration of HGF, becoming in a new treatment modality for MDR-TB.

Relevance of Membrane Contact Sites in Cancer Progression.

Membrane contact sites (MCS) are typically defined as areas of proximity between heterologous or homologous membranes characterized by specific proteins. The study of MCS is considered as an emergent field that shows how crucial organelle interactions are in cell physiology. MCS regulate a myriad of physiological processes such as apoptosis, calcium, and lipid signaling, just to name a few. The membranal interactions between the endoplasmic reticulum (ER)-mitochondria, the ER-plasma membrane, and the vesicular traffic have received special attention in recent years, particularly in cancer research, in which it has been proposed that MCS regulate tumor metabolism and fate, contributing to their progression. However, as the therapeutic or diagnostic potential of MCS has not been fully revisited, in this review, we provide recent information on MCS relevance on calcium and lipid signaling in cancer cells and on its role in tumor progression. We also describe some proteins associated with MCS, like CERT, STIM1, VDAC, and Orai, that impact on cancer progression and that could be a possible diagnostic marker. Overall, these information might contribute to the understanding of the complex biology of cancer cells.

Impact of the gene-gene interactions related to the HIF-1α signaling pathway with the knee osteoarthritis development.

INTRODUCTION/OBJECTIVES: Articular cartilage is the target tissue of osteoarthritis (OA), and because it lacks capillary networks, the microenvironment is hypoxic. Hypoxia inducible factor-1 alpha (HIF-1α) regulates the homeostasis of this tissue. The aim of this study was to investigate whether genetic polymorphisms of the HIF-1α signaling pathway are involved in the development of knee OA. METHOD: We performed a case-control association study and genotyped 134 knee OA patients and 267 healthy controls. All participants were genotyped in order to evaluate 42 SNPs from 22 genes involved in the HIF-1α signaling pathway using the OpenArray technology. Gene-gene interactions (epistasis) were analyzed using the multifactor dimensionality reduction (MDR) method. RESULTS: The MDR analysis showed epistasis between AKT2 (rs8100018) and IGF1 (rs2288377), AKT2 (rs8100018) and IGF1 (rs35767), IGF1 (rs35767) and COL2A1 (rs1793953), and between GSK3B (rs6438552) and IGF1 (rs35767) polymorphisms, with information gain values of 21.24%, 8.37%, 9.93%, and 5.73%, respectively. Additionally, our model allowed us to identify high- and low-risk genotypes among COL2A1 rs1793953, GSK3B rs6438552, AKT2 rs8100018, and IGF1 rs35767 polymorphisms. CONCLUSIONS: Knowing the interactions of these polymorphisms involved in HIF-1α signaling pathway could provide a new diagnostic support tool to identify individuals at high risk of developing knee OA.

Role of phospholipase D in migration and invasion induced by linoleic acid in breast cancer cells.

Linoleic acid (LA) is an essential and omega-6 polyunsaturated fatty acid that mediates a variety of biological processes, including migration and invasion in breast cancer cells. Phospholipase D (PLD) catalyses the hydrolysis of phosphatidylcholine to produce phosphatidic acid and choline. Increases of expression and activity of PLD are reported in several human cancers, including gastric, colorectal, renal, stomach, lung and breast. In this article, we demonstrate that LA induces an increase of PLD activity in MDA-MB-231 breast cancer cells. Particularly, PLD1 and/or PLD2 mediate migration and invasion induced by LA. Moreover, LA induces increases in number and size of spheroids via PLD activity. FFAR1 also mediates migration and invasion, whereas PLD activation induced by LA requires the activities of FFAR1, FFAR4 and EGFR in MDA-MB-231 cells. In summary, PLD plays a pivotal role in migration and invasion induced by LA in MDA-MB-231 breast cancer cells.

Typhus, yellow fever and Medicine in Mexico during the French intervention / El tifo, la fiebre amarilla y la medicina en México durante la intervención francesa.

French intervention in Mexico (1861-1867) is particularly full of episodes of patriotic heroism in terms of military, politic and, even, religious affairs, however this history is also rich in episodes related to diseases and the evolution of Mexican scientific medicine practice, epidemics such as typhus (nowadays knows as rickettsiosis), yellow fever, or cholera. Principally, this context outlined the Mexican history and influenced the course of the nation. The epidemics served as fertile land for the development of medicine science leading by prominent physicians, particularly by doctor Miguel Francisco Jiménez.

El periodo comprendido entre 1861 y 1867, marcado por la ocupación extranjera, particularmente por Francia, es sin lugar a dudas rico en gestas de patriotismo sin igual en la historia de México por la coyuntura política, militar e incluso religiosa del periodo en cuestión; sin embargo, poco se ha abordado de manera concreta el estado que guardaban la salud y la ciencia médica en dicho periodo, lleno de episodios sumamente interesantes en cuanto a epidemias como el tifo, la fiebre amarilla o el cólera, sobre todo cuando estas enfermedades afectaron y marcaron el rumbo de la historia nacional, a la par con el desarrollo de la naciente medicina científica mexicana encabezada por varios médicos, en especial por el Dr. Miguel Francisco Jiménez.

Recombinant human hepatocyte growth factor provides protective effects in cerulein-induced acute pancreatitis in mice.

Acute pancreatitis is a multifactorial disease associated with profound changes of the pancreas induced by release of digestive enzymes that lead to increase in proinflammatory cytokine production, excessive tissue necrosis, edema, and bleeding. Elevated levels of hepatocyte growth factor (HGF) and its receptor c-Met have been observed in different chronic and acute pancreatic diseases including experimental models of acute pancreatitis. In the present study, we investigated the protective effects induced by the recombinant human HGF in a mouse model of cerulein-induced acute pancreatitis. Pancreatitis was induced by 8 hourly administrations of supramaximal cerulein injections (50 µg/kg, ip). HGF treatment (20 µg/kg, iv), significantly attenuated lipase content and amylase activity in serum as well as the degree inflammation and edema overall leading to less severe histologic changes such as necrosis, induced by cerulein. Protective effects of HGF were associated with activation of pro-survival pathways such as Akt, Erk1/2, and Nrf2 and increase in executor survival-related proteins and decrease in pro-apoptotic proteins. In addition, ROS content and lipid peroxidation were diminished, and glutathione synthesis increased in pancreas. Systemic protection was observed by lung histology. In conclusion, our data indicate that HGF exerts an Nrf2 and glutathione-mediated protective effect on acute pancreatitis reflected by a reduction in inflammation, edema, and oxidative stress.

Hyperlipidemic microenvironment conditionates damage mechanisms in human chondrocytes by oxidative stress.

BACKGROUND: Currently, two pathogenic pathways describe the role of obesity in osteoarthritis (OA); one through biomechanical stress, and the other by the contribution of systemic inflammation. The aim of this study was to evaluate the effect of free fatty acids (FFA) in human chondrocytes (HC) expression of proinflammatory factors and reactive oxygen species (ROS). METHODS: HC were exposed to two different concentrations of FFA in order to evaluate the secretion of adipokines through cytokines immunoassays panel, quantify the protein secretion of FFA-treated chondrocytes, and fluorescent cytometry assays were performed to evaluate the reactive oxygen species (ROS) production. RESULTS: HC injury was observed at 48 h of treatment with FFA. In the FFA-treated HC the production of reactive oxygen species such as superoxide radical, hydrogen peroxide, and the reactive nitrogen species increased significantly in a at the two-dose tested (250 and 500 µM). In addition, we found an increase in the cytokine secretion of IL-6 and chemokine IL-8 in FFA-treated HC in comparison to the untreated HC. CONCLUSION: In our in vitro model of HC, a hyperlipidemia microenvironment induces an oxidative stress state that enhances the inflammatory process mediated by adipokines secretion in HC.

Role of HIF-1α signaling pathway in osteoarthritis: A systematic review / Papel da via de sinalização do HIF-1α; na osteoartrite: revisão sistemática

Abstract Osteoarthritis (OA) is the most common form of arthritis and is frequently diagnosed and managed in primary care; it is characterized by loss of articular hyaline cartilage, which is a unique connective tissue that physiologically lacks blood vessels. Articular cartilage survives in a microenvironment devoid of oxygen, which is regulated by hypoxia inducible factor (HIF-1α). HIF-1α is considered the main transcriptional regulator of cellular and developmental response to hypoxia. To date, the relevance of HIF-1α in the assessment of cartilage has increased since its participation is essential in the homeostasis of this tissue. Taking into account the new emerging insights of HIF-1α in the scientific literature in the last years, we focused the present review on the potential role of HIF-1α signaling pathway in OA development, especially in how some genetic factors may influence the maintenance or breakdown of articular cartilage.

Resumo A osteoartrite (OA) é a forma mais comum de artrite e frequentemente é diagnosticada e gerenciada na atenção primária; é caracterizada por perda da cartilagem articular hialina, um tecido conjuntivo único que fisiologicamente carece de vasos sanguíneos. A cartilagem articular sobrevive em um microambiente desprovido de oxigênio, que é regulado pelo fator induzível por hipóxia-1α (HIF-1α). O HIF-1α é considerado o principal regulador transcricional da resposta celular e de desenvolvimento à hipóxia. Na atualidade, a relevância do HIF-1α na avaliação da cartilagem tem aumentado, já que a sua participação é essencial na homeostase desse tecido. Considerando as novas perspectivas emergentes do HIF-1α na literatura científica nos últimos anos, foca-se a presente revisão no potencial papel da via de sinalização do HIF-1α no desenvolvimento da OA, especialmente no modo como alguns fatores genéticos podem influenciar na manutenção ou ruptura da cartilagem articular.

Role of HIF-1α signaling pathway in osteoarthritis: a systematic review.

Osteoarthritis (OA) is the most common form of arthritis and is frequently diagnosed and managed in primary care; it is characterized by loss of articular hyaline cartilage, which is a unique connective tissue that physiologically lacks blood vessels. Articular cartilage survives in a microenvironment devoid of oxygen, which is regulated by hypoxia inducible factor (HIF-1α). HIF-1α is considered the main transcriptional regulator of cellular and developmental response to hypoxia. To date, the relevance of HIF-1α in the assessment of cartilage has increased since its participation is essential in the homeostasis of this tissue. Taking into account the new emerging insights of HIF-1α in the scientific literature in the last years, we focused the present review on the potential role of HIF-1α signaling pathway in OA development, especially in how some genetic factors may influence the maintenance or breakdown of articular cartilage.

Ultrasound in the interstitial pulmonary fibrosis. Can it facilitate a best routine assessment in rheumatic disorders?

Ultrasound (US) is increasing its potential in the assessment of several rheumatic disorders. Recently, different applications of this imaging technique have emerged. Interesting data supporting its utility and validity in the assessment of the lung to detect and quantify interstitial pulmonary fibrosis in rheumatic diseases, even in subclinical phases, have been reported. The main purpose of this review is to provide an overview of the role of US in the assessment of interstitial pulmonary fibrosis in rheumatic disorders and to discuss the current evidence supporting its clinical relevance in daily clinical practice.

Hepatocyte Growth Factor Reduces Free Cholesterol-Mediated Lipotoxicity in Primary Hepatocytes by Countering Oxidative Stress.

Cholesterol overload in the liver has shown toxic effects by inducing the aggravation of nonalcoholic fatty liver disease to steatohepatitis and sensitizing to damage. Although the mechanism of damage is complex, it has been demonstrated that oxidative stress plays a prominent role in the process. In addition, we have proved that hepatocyte growth factor induces an antioxidant response in hepatic cells; in the present work we aimed to figure out the protective effect of this growth factor in hepatocytes overloaded with free cholesterol. Hepatocytes from mice fed with a high-cholesterol diet were treated or not with HGF, reactive oxygen species present in cholesterol overloaded hepatocytes significantly decreased, and this effect was particularly associated with the increase in glutathione and related enzymes, such as γ-gamma glutamyl cysteine synthetase, GSH peroxidase, and GSH-S-transferase. Our data clearly indicate that HGF displays an antioxidant response by inducing the glutathione-related protection system.

Cholesterol Enhances the Toxic Effect of Ethanol and Acetaldehyde in Primary Mouse Hepatocytes.

Obesity and alcohol consumption are risk factors for hepatic steatosis, and both commonly coexist. Our objective was to evaluate the effect of ethanol and acetaldehyde on primary hepatocytes obtained from mice fed for two days with a high cholesterol (HC) diet. HC hepatocytes increased lipid and cholesterol content. HC diet sensitized hepatocytes to the toxic effect of ethanol and acetaldehyde. Cyp2E1 content increased with HC diet, as well as in those treated with ethanol or acetaldehyde, while the activity of this enzyme determined in microsomes increased in the HC and in all ethanol treated hepatocytes, HC and CW. Oxidized proteins were increased in the HC cultures treated or not with the toxins. Transmission electron microscopy showed endoplasmic reticulum (ER) stress and megamitochondria in hepatocytes treated with ethanol as in HC and the ethanol HC treated hepatocytes. ER stress determined by PERK content was increased in ethanol treated hepatocytes from HC mice and CW. Nuclear translocation of ATF6 was observed in HC hepatocytes treated with ethanol, results that indicate that lipids overload and ethanol treatment favor ER stress. Oxidative stress, ER stress, and mitochondrial damage underlie potential mechanisms for increased damage in steatotic hepatocyte treated with ethanol.

[Cholesterol overload in hepatocytes affects nicotinamide adenine dinucleotide phosphate oxidase (NADPH) activity abrogating hepatocyte growth factor (HGF) induced cellular protection]. / La acumulación de colesterol en hepatocitos sobreactiva el fosfato de dinucleótido de adenina y nicotinamida (NADPH) oxidasa pero abroga la respuesta de protección del factor de crecimiento de hepatocitos (HGF).

The increment in the prevalence of obesity incidence in Mexico is leading to the increase in many chronic maladies, including liver diseases. It is well known that lipid-induced liver sensitization is related to the kind of lipid rather than the amount of them in the organ. Cholesterol overload in the liver aggravates the toxic effects of canonical liver insults. However, the status on the repair and survival response elicited by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and the hepatocyte growth factor (HGF) is not completely understood. In the present, work we aimed to figure out the HGF/NADPH oxidase-induced cellular protection in the hepatocyte with a cholesterol overload. Our results show that a hypercholesterolemic diet induced liver damage and steatosis in mice. The hepatocytes isolated from these animals exhibited an increase in basal NADPH oxidase activity, although transcriptional levels of some of its components were decreased. No effect on the oxidase activity was observed in HGF treatments. The protective effect of HGF was abrogated as a result of cholesterol cellular overload, calculated by a survival assay. In conclusion, the cholesterol overload in hepatocytes impairs the HGF/NADPH oxidase-induced cellular protection.

[Characterization of hemodynamic ex vivo model to study endothelial activation by TNF-α in prefunded human veins]. / Caracterización de un modelo hemodinámico ex vivo para el estudio de la activación endotelial por el factor de necrosis tumoral α (TNF-α) en venas humanas perfundidas.

Inflammation is recognized as part of the etiology of numerous diseases. The interaction among cells of the immunological system with local cells and molecules, such as cytokines and chemokines, allows cellular activation and response amplification. The importance of several physicochemical factors like frictional force, vascular flow, shear stress, and pressure is now recognized because they are known to modulate genetic expression and endothelial activation; however, there are very few studies that recreate such cellular microenvironments. Hence, it is of paramount importance to develop new models that will mimic physiological conditions. Our aim was to improve a human vein ex vivo model that would allow endothelial activation in flow conditions, to study the molecular components during adhesion, taking into consideration physicochemical parameters such as flow and shear stress. Endothelial umbilical human vein was used and activated with TNF-a in order to determine U937 monocytic cells adhesion, as well as cytokines secretion and ICAM-1 expression. This model will allow leukocyte adhesion studies, using different inflammatory stimulus, along with the signaling pathways involved in several pathologies.

Acetylcholinesterase is associated with a decrease in cell proliferation of hepatocellular carcinoma cells.

Acetylcholinesterase (AChE), the enzyme that rapidly splits acetylcholine into acetate and choline, presents non-cholinergic functions through which may participate in the control of cell proliferation and apoptosis. These two features are relevant in cancer, particularly in hepatocellular carcinoma (HCC), a very aggressive liver tumor with high incidence and poor prognosis in advanced stages. Here we explored the relation between acetylcholinesterase and HCC growth by testing the influence of AChE on proliferation of Huh-7 and HepG2 cell lines, addressed in monolayer cultures, spheroid formation and human liver tumor samples. Results showed a clear relation in AChE expression and cell cycle progression, an effect which depended on cell confluence. Inhibition of AChE activity led to an increase in cell proliferation, which was associated with downregulation of p27 and cyclins. The fact that Huh-7 and HepG2 cell lines provided similar results lent weight to the relationship of AChE expression with cell cycle progression in hepatoma cell lines at least. Human liver tumor samples exhibited a decrease in AChE activity as compared with normal tissue. The evidence presented herein provides additional support for the proposed tumor suppressor role of AChE, which makes it a potential therapeutic target in therapies against hepatocellular carcinoma.

Free fatty acids enhance the oxidative damage induced by ethanol metabolism in an in vitro model.

In recent years, there has been a growing interest to explore the responsiveness to injury in steatotic hepatocyte. VL-17A cells, which express ADH and Cyp2E1 overloaded with free fatty acids (1 mM of oleic and palmitic acid 2:1) showed an increased oxidative damaged after 24 h free fatty acids treatment when exposed to ethanol (100 mM) for 48 h as a second injury. An increment in reactive oxygen species, determined by DCFH-DA, protein oxidation, and apoptosis were observed although an increase in main antioxidant proteins such as superoxide dismutase 1 and glutathione peroxidase were observed, but failed in gamma-glutamylcysteine synthetase, suggesting a decreased capacity of synthesis of glutathione compared with cells treated only with free fatty acids or ethanol. The increased oxidative stress and toxicity in lipid overloaded VL-17A cells subjected to ethanol exposure were accompanied by increases in Cyp2E1 protein expression. Our data show that lipid loaded in an in vitro model, VL-17A cells, is more susceptible to cell damage and oxidative stress when treated with ethanol.

Cadmio: efectos sobre la salud. Respuesta celular y molecular / Cadmium: effects on health. Cellular and molecular response

El cadmio (Cd) es un metal que se encuentra principalmente en la corteza terrestre y siempre se presenta en combinación con el zinc. Es ampliamente utilizado en la industria. Se considera un contaminante y es liberado al ambiente como subproducto de la extracción de cobre, hierro y zinc. La exposición al Cd puede producir una variedad de efectos adversos tanto en el humano como en los animales. Una vez absorbido se acumula en el organismo por tiempos largos. Dependiendo de la dosis, fuente y tipo de exposición puede dañar varios órganos como el hígado, riñón, pulmón, hueso, testículos y placenta. Los seres humanos están expuestos al Cd principalmente a través de la ingesta de alimentos, del humo del cigarro, así como del agua y aire contaminados con el metal. La entrada de Cd a las células no es uniforme en todos los sistemas y puede ser mediada por transporte pasivo o activo, o por canales de calcio. Se considera que uno de los mecanismos de toxicidad de este metal es debido, en parte, a las especies reactivas de oxígeno, las cuales pueden actuar como segundos mensajeros y por tanto alterar diferentes vías de señalización. Por todo lo expuesto el objetivo de esta revisión es analizar los efectos del Cd sobre la salud, así como sobre la respuesta celular y molecular.

Cadmium (Cd) is a metal found in the earth´s crust, always as part of several, mainly zinc-rich, ores. Cd is considered as an environmental pollutant, it is widely used in the industry. It coexists with other metals and its release into the environment is carried out in parallel with the release of copper, iron and zinc. Cd is known to have numerous undesirable effects on health in both humans and animals. Once absorbed, it is effciently retained in the body, where it accumulates throughout life. Depending on the dose, source and type of exposure it could damage several organs as the liver, kidney, lung, bones, testes and placenta. Impor-tant sources of human intoxication are food, cigarette smoke as well as contaminated water and air. Cd cell uptake is not uniform across all systems. This could be mediated by passive or active transport, or via calcium channels. It is known that the toxicity produced by this metal is due, in part to reactive oxygen species, which could act as second messengers that may alter different signaling cascades. The aim of this review is to analyze the effects of Cd on health, as well as on cellular and molecular response.