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1.
Cell ; 185(10): 1676-1693.e23, 2022 05 12.
Article in English | MEDLINE | ID: mdl-35489334

ABSTRACT

Epidemiological studies reveal that marijuana increases the risk of cardiovascular disease (CVD); however, little is known about the mechanism. Δ9-tetrahydrocannabinol (Δ9-THC), the psychoactive component of marijuana, binds to cannabinoid receptor 1 (CB1/CNR1) in the vasculature and is implicated in CVD. A UK Biobank analysis found that cannabis was an risk factor for CVD. We found that marijuana smoking activated inflammatory cytokines implicated in CVD. In silico virtual screening identified genistein, a soybean isoflavone, as a putative CB1 antagonist. Human-induced pluripotent stem cell-derived endothelial cells were used to model Δ9-THC-induced inflammation and oxidative stress via NF-κB signaling. Knockdown of the CB1 receptor with siRNA, CRISPR interference, and genistein attenuated the effects of Δ9-THC. In mice, genistein blocked Δ9-THC-induced endothelial dysfunction in wire myograph, reduced atherosclerotic plaque, and had minimal penetration of the central nervous system. Genistein is a CB1 antagonist that attenuates Δ9-THC-induced atherosclerosis.


Subject(s)
Cannabis , Cardiovascular Diseases , Hallucinogens , Analgesics , Animals , Cannabinoid Receptor Agonists/pharmacology , Dronabinol/pharmacology , Endothelial Cells , Genistein/pharmacology , Genistein/therapeutic use , Inflammation/drug therapy , Mice , Receptor, Cannabinoid, CB1 , Receptors, Cannabinoid
3.
Circ Res ; 130(12): 1780-1802, 2022 06 10.
Article in English | MEDLINE | ID: mdl-35679369

ABSTRACT

An ensemble of in vitro cardiac tissue models has been developed over the past several decades to aid our understanding of complex cardiovascular disorders using a reductionist approach. These approaches often rely on recapitulating single or multiple clinically relevant end points in a dish indicative of the cardiac pathophysiology. The possibility to generate disease-relevant and patient-specific human induced pluripotent stem cells has further leveraged the utility of the cardiac models as screening tools at a large scale. To elucidate biological mechanisms in the cardiac models, it is critical to integrate physiological cues in form of biochemical, biophysical, and electromechanical stimuli to achieve desired tissue-like maturity for a robust phenotyping. Here, we review the latest advances in the directed stem cell differentiation approaches to derive a wide gamut of cardiovascular cell types, to allow customization in cardiac model systems, and to study diseased states in multiple cell types. We also highlight the recent progress in the development of several cardiovascular models, such as cardiac organoids, microtissues, engineered heart tissues, and microphysiological systems. We further expand our discussion on defining the context of use for the selection of currently available cardiac tissue models. Last, we discuss the limitations and challenges with the current state-of-the-art cardiac models and highlight future directions.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Cell Differentiation , Heart/physiology , Humans , Models, Cardiovascular , Organoids
4.
Neuroophthalmology ; 48(1): 41-45, 2024.
Article in English | MEDLINE | ID: mdl-38357624

ABSTRACT

Anisocoria is a common finding in ophthalmic clinical practice. History taking and examination is critical in appropriately diagnosing and managing anisocoria, as the differential can be extensive ranging from benign to life-threatening entities. This case discusses the presentation of a 22-year-old female with a history of myopia and hyperhidrosis who presented with pharmacologic anisocoria which was presumed to be from inadvertent topical exposure to conventional glycopyrrolate tablets. To our knowledge, pharmacologic mydriasis from exposure to residue from conventional glycopyrrolate tablets has not been reported in the English literature. This case highlights the importance of medication and contact lens handling with anticholinergic agents.

5.
Proc Natl Acad Sci U S A ; 117(32): 19033-19044, 2020 08 11.
Article in English | MEDLINE | ID: mdl-32709748

ABSTRACT

Therapeutic factors secreted by mesenchymal stem cells (MSCs) promote angiogenesis in vivo. However, delivery of MSCs in the absence of a cytoprotective environment offers limited efficacy due to low cell retention, poor graft survival, and the nonmaintenance of a physiologically relevant dose of growth factors at the injury site. The delivery of stem cells on an extracellular matrix (ECM)-based platform alters cell behavior, including migration, proliferation, and paracrine activity, which are essential for angiogenesis. We demonstrate the biophysical and biochemical effects of preconditioning human MSCs (hMSCs) for 96 h on a three-dimensional (3D) ECM-based microgel platform. By altering the macromolecular concentration surrounding cells in the microgels, the proangiogenic phenotype of hMSCs can be tuned in a controlled manner through cell-driven changes in extracellular stiffness and "outside-in" integrin signaling. The softest microgels were tested at a low cell dose (5 × 104 cells) in a preclinical hindlimb ischemia model showing accelerated formation of new blood vessels with a reduced inflammatory response impeding progression of tissue damage. Molecular analysis revealed that several key mediators of angiogenesis were up-regulated in the low-cell-dose microgel group, providing a mechanistic insight of pathways modulated in vivo. Our research adds to current knowledge in cell-encapsulation strategies by highlighting the importance of preconditioning or priming the capacity of biomaterials through cell-material interactions. Obtaining therapeutic efficacy at a low cell dose in the microgel platform is a promising clinical route that would aid faster tissue repair and reperfusion in "no-option" patients suffering from peripheral arterial diseases, such as critical limb ischemia (CLI).


Subject(s)
Mesenchymal Stem Cells/chemistry , Mesenchymal Stem Cells/cytology , Microgels/chemistry , Neovascularization, Physiologic , Animals , Cell Proliferation , Cells, Immobilized/chemistry , Cells, Immobilized/cytology , Cells, Immobilized/metabolism , Extracellular Matrix/genetics , Extracellular Matrix/metabolism , Hindlimb/blood supply , Hindlimb/metabolism , Hindlimb/surgery , Humans , Integrins/genetics , Integrins/metabolism , Ischemia/physiopathology , Ischemia/surgery , Ischemia/therapy , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Mice , Mice, Nude
6.
Ophthalmic Plast Reconstr Surg ; 39(2): 150-155, 2023.
Article in English | MEDLINE | ID: mdl-36095848

ABSTRACT

PURPOSE: In response to the coronavirus (COVID-19) pandemic, teprotumumab production was temporarily halted with resources diverted toward vaccine production. Many patients who initiated treatment with teprotumumab for thyroid eye disease were forced to deviate from the standard protocol. This study investigates the response of teprotumumab when patients receive fewer than the standard 8-dose regimen. METHODS: This observational cross-sectional cohort study included patients from 15 institutions with active or minimal to no clinical activity thyroid eye disease treated with the standard teprotumumab infusion protocol. Patients were included if they had completed at least 1 teprotumumab infusion and had not yet completed all 8 planned infusions. Data were collected before teprotumumab initiation, within 3 weeks of last dose before interruption, and at the visit before teprotumumab reinitiation. The primary outcome measure was reduction in proptosis more than 2 mm. Secondary outcome measures included change in clinical activity score (CAS), extraocular motility restriction, margin reflex distance-1 (MRD1), and reported adverse events. RESULTS: The study included 74 patients. Mean age was 57.8 years, and 77% were female. There were 62 active and 12 minimal to no clinical activity patients. Patients completed an average of 4.2 teprotumumab infusions before interruption. A significant mean reduction in proptosis (-2.9 mm in active and -2.8 mm in minimal to no clinical activity patients, P < 0.01) was noted and maintained during interruption. For active patients, a 3.4-point reduction in CAS ( P < 0.01) and reduction in ocular motility restriction ( P < 0.01) were maintained during interruption. CONCLUSIONS: Patients partially treated with teprotumumab achieve significant reduction in proptosis, CAS, and extraocular muscle restriction and maintain these improvements through the period of interruption.


Subject(s)
COVID-19 , Exophthalmos , Graves Ophthalmopathy , Humans , Female , Middle Aged , Male , Graves Ophthalmopathy/drug therapy , Cross-Sectional Studies
7.
J Mol Cell Cardiol ; 168: 107-114, 2022 07.
Article in English | MEDLINE | ID: mdl-35461823

ABSTRACT

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have advanced our ability to study the basic function of the heart and model cardiac diseases. Due to the complexities in stem cell culture and differentiation protocols, many researchers source their hiPSC-CMs from collaborators or commercial biobanks. Generally, the field has assumed the health of frozen cardiomyocytes is unchanged if the cells adhere to the substrate and commence beating. However, very few have investigated the effects of cryopreservation on hiPSC-CM's functional and transcriptional health at the cellular and molecular level. Here we review methods and challenges associated with cryopreservation, and examine the effects of cryopreservation on the functionality (contractility and calcium handling) and transcriptome of hiPSC-CMs from six healthy stem cell lines. Utilizing protein patterning methods to template physiological cell aspect ratios (7:1, length:width) in conjunction with polyacrylamide (PA) hydrogels, we measured changes in force generation and calcium handling of single hiPSC-CMs. We observed that cryopreservation altered the functionality and transcriptome of hiPSC-CMs towards larger sizes and contractile force as assessed by increased spread area and volume, single cell traction force microscopy and delayed calcium dynamics. hiPSC-CMs are broadly used for basic science research, regenerative medicine, and testing biological therapeutics. This study informs the design of experiments utilizing hiPSC-CMs to avoid confounding functional changes due to cryopreservation with other treatments.


Subject(s)
Induced Pluripotent Stem Cells , Calcium/metabolism , Cell Differentiation , Cells, Cultured , Cryopreservation , Humans , Induced Pluripotent Stem Cells/metabolism , Myocytes, Cardiac/metabolism
8.
BMC Cardiovasc Disord ; 22(1): 122, 2022 03 22.
Article in English | MEDLINE | ID: mdl-35317745

ABSTRACT

Stem-cell derived in vitro cardiac models have provided profound insights into mechanisms in cardiac development and disease. Efficient differentiation of specific cardiac cell types from human pluripotent stem cells using a three-step Wnt signaling modulation has been one of the major discoveries that has enabled personalized cardiovascular disease modeling approaches. Generation of cardiac cell types follow key development stages during embryogenesis, they intuitively are excellent models to study cardiac tissue patterning in primitive cardiac structures. Here, we provide a brief overview of protocols that have laid the foundation for derivation of stem-cell derived three-dimensional cardiac models. Further this article highlights features and utility of the models to distinguish the advantages and trade-offs in modeling embryonic development and disease processes. Finally, we discuss the challenges in improving robustness in the current models and utilizing developmental principles to bring higher physiological relevance. In vitro human cardiac models are complimentary tools that allow mechanistic interrogation in a reductionist way. The unique advantage of utilizing patient specific stem cells and continued improvements in generating reliable organoid mimics of the heart will boost predictive power of these tools in basic and translational research.


Subject(s)
Organoids , Pluripotent Stem Cells , Cell Differentiation , Heart , Humans , Organoids/physiology
9.
Neuroophthalmology ; 44(1): 41-44, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32076449

ABSTRACT

Carotid-jugular fistulae are rare complications of penetrating head and neck trauma. We report an unusual case of an external carotid-internal jugular fistula presenting with diplopia due to sixth nerve paresis. A 38-year-old Caucasian female presented in the setting of acute neurovascular neck trauma and weeks later developed symptomatic diplopia. An acquired carotid-internal jugular fistula affecting the abducens nerve secondarily via compression from a distended inferior petrosal sinus was diagnosed and treated using endovascular coil embolisation, resolving the patient's symptoms. A posteriorly draining external carotid artery-internal jugular venous fistula can be an uncommon cause of a compressive sixth cranial nerve palsy.

13.
Biotechnol Bioeng ; 113(6): 1155-63, 2016 06.
Article in English | MEDLINE | ID: mdl-26498484

ABSTRACT

Self-assembly in tissue engineering refers to the spontaneous chemical or biological association of components to form a distinct functional construct, reminiscent of native tissue. Such self-assembled systems have been widely used to develop platforms for the delivery of therapeutic and/or bioactive molecules and various cell populations. Tissue morphology and functional characteristics have been recapitulated in several self-assembled constructs, designed to incorporate stimuli responsiveness and controlled architecture through spatial confinement or field manipulation. In parallel, owing to substantial functional properties, scaffold-free cell-assembled devices have aided in the development of functional neotissues for various clinical targets. Herein, we discuss recent advancements and future aspirations in scaffold and scaffold-free self-assembled devices for regenerative medicine purposes. Biotechnol. Bioeng. 2016;113: 1155-1163. © 2015 Wiley Periodicals, Inc.


Subject(s)
Biomimetic Materials/chemical synthesis , Extracellular Matrix/chemistry , Guided Tissue Regeneration/instrumentation , Guided Tissue Regeneration/methods , Tissue Engineering/methods , Tissue Scaffolds , Humans , Regenerative Medicine/instrumentation , Regenerative Medicine/methods , Tissue Engineering/instrumentation
14.
Bioconjug Chem ; 26(7): 1297-306, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-25290910

ABSTRACT

Intradiscal injection of growth factors or cells has been shown to attenuate symptoms of intervertebral disc degeneration. However, different approaches are needed to overcome limitations such as short-term efficacy and leakage of the injected solutions. The current study aims at creating a platform for the realization of functional cell factories by using in parallel cell delivery and gene therapy approaches. Superfect, a transfecting agent, was used as nonviral gene vector because of its ability to form complexes with plasmid DNA (polyplexes). Polyplexes were loaded into collagen hollow microsphere reservoirs, and their ability to transfect cells was ascertained in vitro. Adipose-derived stem cells were then embedded in three-dimensional (3D) microgels composed of type II collagen/hyaluronan, which mimics the environmental cues typical of the healthy nucleus pulposus. These were functionalized with polyplex-loaded collagen hollow spheres and the secretion of the target protein was assessed quantitatively. Delivery of polyplexes from a reservoir system lowered their toxicity significantly while maintaining high levels of transfection in a monolayer culture. In 3D microgels, lower levels of transfection were observed, however; increasing levels of luciferase were secreted from the microgels over 7 days of culture. These results indicate that 3D microgels, functionalized with polyplex-loaded reservoirs offer a reliable platform for the production of cell factories that are able to manufacture targeted therapeutic proteins for regenerative therapies that have applications in nucleus pulposus repair.


Subject(s)
Cell Culture Techniques , Collagen Type II/chemistry , Hyaluronic Acid/chemistry , Stem Cells/cytology , Tissue Scaffolds/chemistry , Transfection , Animals , Cattle , Cell Culture Techniques/methods , Cells, Cultured , DNA/administration & dosage , Intervertebral Disc/physiology , Plasmids/administration & dosage , Regeneration , Stem Cells/metabolism , Transfection/methods
15.
Ophthalmic Plast Reconstr Surg ; 31(3): e68-70, 2015.
Article in English | MEDLINE | ID: mdl-24814274

ABSTRACT

Ipilimumab is a monoclonal antibody to cytotoxic T-lymphocyte antigen-4, a negative regulator of T-cell-mediated immune response. Ipilimumab is approved by the US Food and Drug Administration for the treatment of advanced melanoma. However, its use frequently has been associated with immune-related side effects, which can be explained by its mechanism of action. More common adverse effects include dermatitis, colitis, hepatitis, and endocrinopathies, but many less common immune-related adverse effects that involve various tissues and organ systems have been reported with more widespread use of ipilimumab since its approval in 2011. A case of bilateral orbital inflammatory syndrome secondary to ipilimumab, in a patient undergoing adjuvant treatment for metastatic melanoma, is reported.


Subject(s)
Antibodies, Monoclonal/adverse effects , Immunotherapy/adverse effects , Orbital Pseudotumor/chemically induced , CTLA-4 Antigen/immunology , Humans , Ipilimumab , Lymphatic Metastasis , Magnetic Resonance Imaging , Male , Melanoma/drug therapy , Melanoma/secondary , Middle Aged , Orbital Pseudotumor/diagnosis , Skin Neoplasms/drug therapy , Skin Neoplasms/pathology
16.
Int J Radiat Biol ; 100(6): 890-902, 2024.
Article in English | MEDLINE | ID: mdl-38631047

ABSTRACT

Purpose: Continuous exposure to ionizing radiation at a low dose rate poses significant health risks to humans on deep space missions, prompting the need for mechanistic studies to identify countermeasures against its deleterious effects. Mitochondria are a major subcellular locus of radiogenic injury, and may trigger secondary cellular responses through the production of reactive oxygen species (mtROS) with broader biological implications. Methods and Materials: To determine the contribution of mtROS to radiation-induced cellular responses, we investigated the impacts of protracted γ-ray exposures (IR; 1.1 Gy delivered at 0.16 mGy/min continuously over 5 days) on mitochondrial function, gene expression, and the protein secretome of human HCA2-hTERT fibroblasts in the presence and absence of a mitochondria-specific antioxidant mitoTEMPO (MT; 5 µM). Results: IR increased fibroblast mitochondrial oxygen consumption (JO2) and H2O2 release rates (JH2O2) under energized conditions, which corresponded to higher protein expression of NADPH Oxidase (NOX) 1, NOX4, and nuclear DNA-encoded subunits of respiratory chain Complexes I and III, but depleted mtDNA transcripts encoding subunits of the same complexes. This was associated with activation of gene programs related to DNA repair, oxidative stress, and protein ubiquination, all of which were attenuated by MT treatment along with radiation-induced increases in JO2 and JH2O2. IR also increased secreted levels of interleukin-8 and Type I collagens, while decreasing Type VI collagens and enzymes that coordinate assembly and remodeling of the extracellular matrix. MT treatment attenuated many of these effects while augmenting others, revealing complex effects of mtROS in fibroblast responses to IR. Conclusion: These results implicate mtROS production in fibroblast responses to protracted radiation exposure, and suggest potentially protective effects of mitochondrial-targeted antioxidants against radiogenic tissue injury in vivo.


Subject(s)
Fibroblasts , Gamma Rays , Mitochondria , Reactive Oxygen Species , Humans , Fibroblasts/radiation effects , Fibroblasts/metabolism , Reactive Oxygen Species/metabolism , Mitochondria/radiation effects , Mitochondria/metabolism , Gamma Rays/adverse effects , Cell Line , Radiation Exposure/adverse effects , Organophosphorus Compounds , Piperidines
17.
Cureus ; 15(2): e35528, 2023 Feb.
Article in English | MEDLINE | ID: mdl-37007350

ABSTRACT

Suprachoroidal hemorrhage is a rare and potentially devastating clinical entity seen in individuals on anticoagulation presenting with severe unilateral eye pain, sudden vision loss, and elevated intraocular pressures. Herein, we report the first case of aseptic orbital cellulitis caused by recurrent spontaneous suprachoroidal hemorrhage. This case highlights an example of non-infectious orbital cellulitis arising from choroidal pathology in the setting of uncontrolled intraocular pressures and recurrent intraocular bleeding. Surgical intervention with blood drainage should be considered to prevent complications and preserve the globe.

18.
Ophthalmic Plast Reconstr Surg ; 28(2): e32-3, 2012.
Article in English | MEDLINE | ID: mdl-21562440

ABSTRACT

Astigmatic changes have been shown to occur after ptosis repair due to the altered vector forces on the underlying cornea from the repositioned upper eyelid. The astigmatic change is usually transient, but it may affect a patient's vision for at least the first few months after surgery. The authors present a case of a patient who underwent ptosis repair and subsequently developed postoperative decline in best-corrected visual acuity due to previously undiagnosed keratoconus. The patient's irregular astigmatism seems to have been masked by the ptotic upper eyelid, which we postulate to have acted similar to a stenopaic slit. Correction of the upper eyelid ptosis unveiled previously asymptomatic irregular astigmatism including vertical coma, leading to alteration in the optical wavefront and resultant image degradation.


Subject(s)
Blepharoplasty , Blepharoptosis/surgery , Keratoconus/diagnosis , Postoperative Complications , Vision Disorders/etiology , Astigmatism/diagnosis , Corneal Topography , Humans , Male , Middle Aged , Visual Acuity/physiology
19.
Cardiovasc Res ; 118(1): 20-36, 2022 01 07.
Article in English | MEDLINE | ID: mdl-33757124

ABSTRACT

Manifestations of cardiovascular diseases (CVDs) in a patient or a population differ based on inherent biological makeup, lifestyle, and exposure to environmental risk factors. These variables mean that therapeutic interventions may not provide the same benefit to every patient. In the context of CVDs, human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) offer an opportunity to model CVDs in a patient-specific manner. From a pharmacological perspective, iPSC-CM models can serve as go/no-go tests to evaluate drug safety. To develop personalized therapies for early diagnosis and treatment, human-relevant disease models are essential. Hence, to implement and leverage the utility of iPSC-CMs for large-scale treatment or drug discovery, it is critical to (i) carefully evaluate the relevant limitations of iPSC-CM differentiations, (ii) establish quality standards for defining the state of cell maturity, and (iii) employ techniques that allow scalability and throughput with minimal batch-to-batch variability. In this review, we briefly describe progress made with iPSC-CMs in disease modelling and pharmacological testing, as well as current iPSC-CM maturation techniques. Finally, we discuss current platforms for large-scale manufacturing of iPSC-CMs that will enable high-throughput drug screening applications.


Subject(s)
Biomedical Research , Cardiology , Cardiovascular Agents/pharmacology , Cardiovascular Diseases/drug therapy , Cell Differentiation , Cell Proliferation , Drug Discovery , Induced Pluripotent Stem Cells/drug effects , Myocytes, Cardiac/drug effects , Cardiotoxicity , Cardiovascular Agents/toxicity , Cardiovascular Diseases/chemically induced , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/pathology , Cell Culture Techniques, Three Dimensional , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Clinical Decision-Making , Humans , Induced Pluripotent Stem Cells/metabolism , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Phenotype , Risk Assessment , Toxicity Tests
20.
Stem Cell Res ; 65: 102969, 2022 12.
Article in English | MEDLINE | ID: mdl-36427473

ABSTRACT

Hispanics are the fastest-growing minority group in the United States. There has been a burgeoning interest in understanding the reasons underlying health disparities among this population. To facilitate the modeling and investigation of diseases that differentially impact Hispanics, we generated three induced pluripotent stem cell (iPSC) lines from the peripheral blood mononuclear cells (PBMCs) of healthy Hispanic subjects. All three lines exhibited normal morphology and karyotypes, robust expression of pluripotency markers, and the capacity for trilineage differentiation. The derivatives of these lines will serve as valuable ethnic-appropriate cell sources for further mechanistic studies on diseases impacting Hispanics.


Subject(s)
Induced Pluripotent Stem Cells , Humans , Leukocytes, Mononuclear
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