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1.
Cells ; 11(3)2022 01 31.
Article de Anglais | MEDLINE | ID: mdl-35159299

RÉSUMÉ

Cancer is one of the leading diseases, causing deaths worldwide. Nearly 10 million deaths were reported in 2020 due to cancer alone. Several factors are involved in cancer progressions, such as lifestyle and genetic characteristics. According to a recent report, extracellular vesicles (EVs) are involved in cancer initiation, progression, and therapy failure. EVs can play a major role in intracellular communication, the maintenance of tissue homeostasis, and pathogenesis in several types of diseases. In a healthy person, EVs carry different cargoes, such as miRNA, lncRNA etc., to help other body functions. On the other hand, the same EV in a tumor microenvironment carries cargoes such as miRNA, lncRNA, etc., to initiate or help cancer progression at various stages. These stages may include the proliferation of cells and escape from apoptosis, angiogenesis, cell invasion, and metastasis, reprogramming energy metabolism, evasion of the immune response, and transfer of mutations. Tumor-derived EVs manipulate by altering normal functions of the body and affect the epigenetics of normal cells by limiting the genetic makeup through transferring mutations, histone modifications, etc. Tumor-derived EVs also pose therapy resistance through transferring drug efflux pumps and posing multiple drug resistances. Such EVs can also help as biomarkers for different cancer types and stages, which ultimately help with cancer diagnosis at early stages. In this review, we will shed light on EVs' role in performing normal functions of the body and their position in different hallmarks of cancer, in altering the genetics of a normal cell in a tumor microenvironment, and their role in therapy resistance, as well as the importance of EVs as diagnostic tools.


Sujet(s)
Vésicules extracellulaires , microARN , Tumeurs , ARN long non codant , Vaccins , Vésicules extracellulaires/métabolisme , Humains , microARN/génétique , Tumeurs/traitement médicamenteux , Tumeurs/thérapie , ARN long non codant/métabolisme , Microenvironnement tumoral
2.
Chem Biol Interact ; 329: 109112, 2020 Sep 25.
Article de Anglais | MEDLINE | ID: mdl-32360284

RÉSUMÉ

Till now monocrotophos (MCP) has been addressed as a neurotoxic stressor. Limited studies investigate its aftermath on bone pathologies. Given the fact that MCP is a propensely used insecticide in developing countries, this study investigates its potential to mirror osteoporotic features and bone loss incurred in a rodent model. Briefly, Swiss albino mice were orally gavaged daily with varying doses of MCP for 8 weeks. Musculoskeletal changes were analyzed through micro-computed tomography and histology. A series of in vitro and ex vivo cell culture experiments were performed on MC3T3E-1 and primary osteoclast cultures. Results highlight that oral gavaging with MCP causes bone loss from the cortico-trabecular interface by decreasing the osteoblast and increasing the osteoclast number. Results from in vitro studies establish that MCP treatment increases the TRAP-positive multinucleated cell number during osteoclast differentiation. Ex-vivo experiments with MCP-treated animal sera further substantiate the in vivo claims with significant decreases seen in cell viability, proliferation, mineralization and differentiation studies. In conclusion MCP induces osteoclastogenesis (bone loss) on direct stimulation and alters the circulating factors in MCP-treated serum. Holistically, this work would be of potential significance to patients suffering from pesticide induced osteoporosis.


Sujet(s)
Os spongieux/effets des médicaments et des substances chimiques , Différenciation cellulaire/effets des médicaments et des substances chimiques , Os cortical/effets des médicaments et des substances chimiques , Insecticides/toxicité , Monocrotophos/toxicité , Ostéogenèse/effets des médicaments et des substances chimiques , Animaux , Os spongieux/imagerie diagnostique , Os spongieux/physiologie , Lignée cellulaire , Prolifération cellulaire/effets des médicaments et des substances chimiques , Os cortical/imagerie diagnostique , Os cortical/physiologie , Mâle , Souris , Ostéoblastes/cytologie , Ostéoblastes/métabolisme , Microtomographie aux rayons X
3.
Neurotox Res ; 36(4): 700-711, 2019 Nov.
Article de Anglais | MEDLINE | ID: mdl-31367921

RÉSUMÉ

Prenatal and early life exposure of chlorpyrifos (CPF), a widely used pesticide, is known to cause neuronal deficits and Parkinson's disease (PD). However, data about the effect of its exposure at adult stages on PD-like symptoms and associated bone loss is scanty. In the present study, we investigated the impact of CPF on the behavioral alterations seen in PD using adult Swiss albino mice. PD is often associated with bone loss. Hence, skeletal changes were also evaluated using micro-computed tomography and histology. MPTP was used as a positive control. Cell culture studies using MC3T3E-1, SHSY5Y, and primary osteoclast cultures were done to understand the cellular mechanism for the behavioral and skeletal changes. Our results showed that CPF treatment leads to PD-like symptoms due to the loss of dopaminergic neurons. Moreover, CPF has a deleterious effect on the trabecular bone through both indirect changes in circulating factors and direct stimulation of multinucleate osteoclast cell formation. The impact on the bone mass was even stronger than MPTP. In conclusion, this is the first report demonstrating that CPF induces parkinsonian features in adult Swiss albino mice and it is accompanied by loss of trabecular bone.


Sujet(s)
Chlorpyriphos/toxicité , Insecticides/toxicité , Ostéoporose/induit chimiquement , Ostéoporose/anatomopathologie , Syndromes parkinsoniens/induit chimiquement , Syndromes parkinsoniens/anatomopathologie , Acetylcholinesterase/métabolisme , Animaux , Comportement animal/effets des médicaments et des substances chimiques , Résorption osseuse/métabolisme , Différenciation cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Corps strié/effets des médicaments et des substances chimiques , Corps strié/métabolisme , Dopamine/métabolisme , Neurones dopaminergiques/effets des médicaments et des substances chimiques , Humains , Vertèbres lombales/effets des médicaments et des substances chimiques , Vertèbres lombales/anatomopathologie , Mâle , Souris , Ostéoblastes/effets des médicaments et des substances chimiques , Ostéoporose/métabolisme , Syndromes parkinsoniens/métabolisme
4.
Toxicol Appl Pharmacol ; 363: 154-163, 2019 01 15.
Article de Anglais | MEDLINE | ID: mdl-30529163

RÉSUMÉ

Bone loss is a non-motor symptom of Parkinson's disease (PD). It is unclear whether a patient's immobility or the endocrine changes in the body causes bone deterioration. To address this issue, we used an animal model of the disease where Swiss albino mice were injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on day 1 and were left untreated for eight weeks. Behavioral phenotypes of PD, and striatal acetylcholinesterase and dopamine levels were measured. Cortical and trabecular bones were assessed by µ-CT and histology. Gene expression studies were done through quantitative real-time PCR. Effect of MPP+ and MPTP-treated mice serum on MC3T3E-1, SH-SY5Y, and primary osteoclast cells were also studied. Our results demonstrated that MPTP treatment leads to PD like symptoms. It shows a loss of trabecular bone mass and quality by decreasing osteoblast and increased osteoclast number and activity. This effect was accompanied by reduced osteogenic and elevated osteoclastogenic genes expression. While MPP+ had a cytotoxic effect on dopaminergic neurons, it did not affect bone cells. However, ex-vivo treatment of the serum from MPTP-treated mice decreased osteoblastogenesis and increased osteoclastogenesis in cell culture. In conclusion, our study suggests that MPTP-induced parkinsonian features in mice leads to trabecular bone loss by decreased bone formation and increased bone resorption due to changes in the serum circulating factors. This study characterizes the microarchitectural and cellular changes in the skeleton of a mouse model of PD that can be further utilized to investigate therapeutic avenues to treat bone loss in PD patients.


Sujet(s)
Résorption osseuse/anatomopathologie , Os spongieux/anatomopathologie , Intoxication au MPTP/complications , Ostéogenèse , Ostéoporose/anatomopathologie , 1-Méthyl-4-phényl-1,2,3,6-tétrahydropyridine/administration et posologie , Animaux , Résorption osseuse/étiologie , Lignée cellulaire tumorale , Modèles animaux de maladie humaine , Humains , Intoxication au MPTP/étiologie , Mâle , Souris , Souris de lignée C57BL , Ostéoblastes/physiologie , Ostéoclastes/physiologie , Ostéoporose/étiologie , Culture de cellules primaires
5.
Pract Radiat Oncol ; 9(2): 115-122, 2019 Mar.
Article de Anglais | MEDLINE | ID: mdl-30447405

RÉSUMÉ

PURPOSE: Many authors suggest that extremity soft tissue sarcomas (ESTS) do not change significantly in size during preoperative radiation therapy (RT). This cone beam computed tomography study investigates the justification to deliver the entire course with 1 initial RT plan by observing anatomic changes during RT. METHODS AND MATERIALS: Between 2015 and 2017, 99 patients with ESTS were treated with either curative (n = 80) or palliative intent (n = 19) with a regimen of at least 6 fractions. The clinical target volume to planning target volume margin was 1 cm. Action levels were assigned by radiation technicians. An extremity contour change of >1 cm and/or tumor size change >0.5 cm required a physician's action before the next fraction. RESULTS: A total of 982 cone beam computed tomography logfiles were studied. In 41 of 99 patients, the dose coverage of the initial treatment plan was fully satisfactory throughout the RT course. However, action levels were observed in 58 patients (59%). In 41 of these 58 patients, a contour increase of 5 to 23 mm was noted (29 tumor size increase only, 3 extremity contour increase, and 9 both). In 21 of 58 patients, a decrease of 5 to 33 mm was observed (20 tumor size decrease only and 1 tumor size decrease and extremity contour decrease). In 4 cases, contours initially increased and subsequently decreased. In 33 of 41 patients with increasing contours, the dose distribution adequately covered gross tumor volume because of the 1 cm planning target volume margin applied. For the remaining 8 patients (8%), the plan needed to be adapted. CONCLUSIONS: ESTS volumes may change substantially during RT in 59% of all patients, leading to plan adaptations resulting from increased volumes in 8%. Daily critical observation of these patients is mandatory to avoid geographic misses because of increases in size and overdosing of normal tissues when masses shrink.


Sujet(s)
Planification de radiothérapie assistée par ordinateur/méthodes , Sarcomes/radiothérapie , Tumeurs des tissus mous/radiothérapie , Charge tumorale/effets des radiations , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Tomodensitométrie à faisceau conique , Membres/imagerie diagnostique , Membres/chirurgie , Femelle , Humains , Imagerie par résonance magnétique , Mâle , Adulte d'âge moyen , Traitement néoadjuvant/méthodes , Stadification tumorale , Organes à risque/imagerie diagnostique , Organes à risque/effets des radiations , Études rétrospectives , Sarcomes/imagerie diagnostique , Sarcomes/anatomopathologie , Tumeurs des tissus mous/imagerie diagnostique , Tumeurs des tissus mous/anatomopathologie
6.
Toxicol Ind Health ; 32(7): 1153-65, 2016 Jul.
Article de Anglais | MEDLINE | ID: mdl-25227224

RÉSUMÉ

Our earlier study had shown that low concentrations of monocrotophos (MCP) elicited dopaminergic features of Parkinson's disease (PD) in the nematode Caenorhabditis elegans In the present study, the effect of low doses of MCP on the striatal dopaminergic neurons was investigated using the mouse model system. MCP was initially screened for its ability to cause any neurobehavioral deficits and alterations in the dopaminergic system in Swiss albino mice, aged 8 weeks and weighing 25-30 g, with repeated doses at 0.3 and 0.6 mg/kg body weight (b.w.)/day for 7 days and 30 days. Mice were treated with four intraperitoneal injections for every 2 h with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) at the dosage of 14 mg/kg b.w. MCP was administered to these mice at the above-mentioned doses for 7 days. Mice administered with MCP alone revealed a significant (p < 0.05) reduction in the dopamine (DA) content at both 7 and 30 days and showed a significant (p < 0.05) increase in neurobehavioral deficits. Interestingly, when MCP was administered for 7 days to MPTP-treated mice, further significant decrease in both DA content and increase in neurobehavioral deficits were apparent. The extent of reactive oxygen species and lipid peroxidation were markedly increased, while the ratio of reduced to oxidized glutathione levels were significantly decreased (p < 0.05) in the treated mice as compared to the control. Significant histopathological alterations and a marked reduction in the number of tyrosine hydroxylase positive cells were evident in striatum of mice treated with higher doses of MCP. These changes were comparable to that seen in mice treated with MPTP and post-administered lower doses of MCP. Our findings suggest that MCP per se has the propensity to induce pathological changes in the dopaminergic neurons as well as augment the degeneration in a compromised nigrostriatal system such as that in PD.


Sujet(s)
Corps strié/effets des médicaments et des substances chimiques , Insecticides/toxicité , Monocrotophos/toxicité , Maladie de Parkinson/anatomopathologie , 1-Méthyl-4-phényl-1,2,3,6-tétrahydropyridine/administration et posologie , Animaux , Comportement animal/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Dopamine/métabolisme , Relation dose-effet des médicaments , Disulfure de glutathion/métabolisme , Injections péritoneales , Peroxydation lipidique/effets des médicaments et des substances chimiques , Mâle , Souris , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Neurotoxines/toxicité , Maladie de Parkinson/étiologie , Espèces réactives de l'oxygène/métabolisme , Tyrosine 3-monooxygenase/métabolisme
7.
CNS Neurol Disord Drug Targets ; 11(8): 993-1000, 2012 Dec.
Article de Anglais | MEDLINE | ID: mdl-23244418

RÉSUMÉ

Positive correlations have been suggested between usage of pesticides and the incidence of Parkinson's disease (PD) through epidemiological as well as few experimental evidences. Organophosphorus insecticides (OPI), which are extensively used in agricultural and household insect control, have been the subject of increasing concern in the past decades due to their neurotoxic potential. However, very few studies have demonstrated the potentials of OPI to induce features of PD in model organisms. In the present study, Caenorhabditis elegans was selected as the model organism to evaluate the potential of monocrotophos (MCP), an OPI, to elicit dopaminergic features of Parkinson's disease in terms of dopamine content, basic movement and integrity of dopaminergic neurons along with its effect on acetylcholinesterase (AChE) activity and life span. All the responses elicited by MCP were compared with that elicited by 1-methyl-4-phenyl- 1, 2, 3, 6-tetrahydropyridine (MPTP) in both N2 and BZ555 worms. N2 worms were exposed to varying concentrations of MCP (50, 100 and 200 µM) or MPTP (200, 300 and 400 µM) for 48 hours and locomotory rate, as measured by the number of body bends made in 20 seconds, was enumerated. Worms subjected to the same dose paradigms were also analyzed for the dopamine content by HPLC. The results indicated a significant reduction in the dopamine levels in the worms that were treated with MCP/MPTP and this correlated with the changes in locomotion compared to untreated worms. Worms treated with MCP also exhibited significant reduction in AChE activity. Both MPTP and MCP caused a marked reduction in life span in the worms. Transgenic worms (BZ555, which has GFP tagged to its 8 dopaminergic neurons) exposed to MCP and MPTP at the above concentrations showed a dose-dependent reduction in the number of green pixels in CEP and ADE neurons which also correlated with the neurodegeneration as visualized by decreased fluorescence in photomicrographs. Taken together, our data demonstrate that low levels of MCP elicits dopaminergic features of PD in C. elegans.


Sujet(s)
Caenorhabditis elegans/métabolisme , Dopamine/métabolisme , Neurones dopaminergiques/métabolisme , Insecticides/toxicité , Monocrotophos/toxicité , Syndrome parkinsonien secondaire/métabolisme , Animaux , Caenorhabditis elegans/effets des médicaments et des substances chimiques , Neurones dopaminergiques/effets des médicaments et des substances chimiques , Neurones dopaminergiques/anatomopathologie , Activité motrice/effets des médicaments et des substances chimiques , Activité motrice/physiologie , Composés organiques du phosphore/toxicité , Syndrome parkinsonien secondaire/induit chimiquement , Syndrome parkinsonien secondaire/anatomopathologie
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