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Objective: The objective of this study was to ascertain pegloticase persistence and adverse events associated with concomitant immunomodulatory drug treatment in patients with gout., Methods: We conducted a retrospective analysis of patients with gout using the American College of Rheumatology's Rheumatology Informatics System for Effectiveness registry from January 2016 through June 2020. The first pegloticase infusion defined the index date. Based on concomitant immunomodulatory drug treatment, we identified three exposure groups: (1) immunomodulatory drug initiators (patients initiating an immunomodulatory prescription ±60 days from the index date), (2) prevalent immunomodulatory drug recipients (patients receiving their first immunomodulatory drug prescription >60 days before the index date with at least one prescription within ±60 days of the index date), and (3) immunomodulatory nonrecipients (patients receiving pegloticase without concomitant immunomodulatory drugs). We calculated the proportion of patients who achieved serum urate levels ≤6 mg/dL and who had laboratory abnormalities (white blood cell count <3.4 x 10 9 /L, platelet count <135,000, hematocrit level <30%, alanine aminotransferase or aspartate aminotransferase level ≥1.5 times the upper limit normal value) within 180 days after the index date. Cox regression analyzed time to pegloticase discontinuation, controlling for potential confounders., Results: We identified 700 pegloticase recipients (91 immunomodulatory drug initiators, 33 prevalent immunomodulatory drug recipients, and 576 nonrecipients), with a median follow-up of 14 months. Immunomodulatory drug recipients were less likely to discontinue pegloticase. The adjusted hazard ratios of pegloticase discontinuation associated with concomitant immunomodulatory drug initiation and prevalent treatment were 0.52 (95% confidence interval [CI] 0.37-0.75) and 0.69 (95% CI 0.42-1.16), respectively. Laboratory abnormalities were uncommon (<5%) and were not higher in concomitant immunomodulatory drug treatment., Conclusion: Consistent with clinical trials, results from this large observational registry suggest that concomitant immunomodulatory drug treatment improves pegloticase persistence., (© 2024 The Authors. Arthritis Care & Research published by Wiley Periodicals LLC on behalf of American College of Rheumatology.)

Objective: Thyroid eye disease (TED) is an autoimmune, inflammatory disease resulting in retro-orbital fat and extraocular muscle expansion. TED quiets ("inactivates") as inflammation wanes; however, signs/symptoms often persist. Signs/symptoms of the disease and the impact on quality of life (QoL) were examined in noninflammatory and inflammatory TED., Methods: Data of patients with moderate-to-severe TED were collected from treating physicians. Clinical activity score (CAS, 6/7 measures available) was used to classify TED as inflammatory (CAS ≥ 3) or noninflammatory (CAS = 0 or 1). QoL impact was scored as 1 = "not at all impaired" to 7 = "extremely impaired." Patients with noninflammatory TED were further grouped into longer (>3 years) and shorter (≤3 years) disease courses., Results: Patients with inflammatory (N = 307) and noninflammatory (N = 281) TED had comparable age (50.0 ± 13.3 years vs 48.3 ± 13.8 years), gender (66% men vs 64% women), TED duration (4.0 ± 4.9 years vs 4.6 ± 5.5 years), and proportion of smokers (15% vs 11%). The most common signs/symptoms of noninflammatory TED included ocular dryness/grittiness (77%), proptosis (56%), excessive tearing (43%), soft tissue edema (42%), conjunctival redness (24%) decreased vision (24%), and eye muscle involvement (22%; 14% had diplopia). All signs/symptoms were less frequently reported in these patients than in those with inflammatory TED. QoL was impacted by noninflammatory TED, although to a lesser degree than the inflammatory disease (3.6 ± 1.5 vs 4.7 ± 1.4). However, mental health issues were similarly reported. Patients with noninflammatory TED with a longer disease course (9.0 ± 6.0 years) had similar QoL impact, mental health diagnoses, and TED signs/symptoms as those with a shorter disease course (1.4 ± 1.0 years)., Conclusion: The signs/symptoms of TED often chronically persist long after TED has "quieted," continuing to impact a patient's QoL and mental health. These data suggest that moderate-to-severe TED should be thought of as a robust symptomatic chronic disease, regardless of its inflammatory status., (Copyright © 2022 AACE. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate teprotumumab safety/efficacy in patients with thyroid eye disease (TED) who were nonresponsive or who experienced a disease flare., Design: The Treatment of Graves' Orbitopathy to Reduce Proptosis with Teprotumumab Infusions in an Open-Label Clinical Extension Study (OPTIC-X) is a teprotumumab treatment and re-treatment trial following the placebo-controlled teprotumumab Phase 3 Treatment of Graves' Orbitopathy (Thyroid Eye Disease) to Reduce Proptosis with Teprotumumab Infusions in a Randomized, Placebo-Controlled, Clinical Study (OPTIC) trial., Participants: Patients who previously received placebo (n = 37) or teprotumumab (n = 14) in OPTIC., Methods: OPTIC nonresponders or those who flared (≥2-mm increase in proptosis, ≥2-point increase in clinical activity score [CAS], or both) during follow-up were treated for the first time (previous placebo patients) or re-treated with teprotumumab in OPTIC-X with 8 infusions over 24 weeks., Main Outcome Measures: Proptosis response and safety. Secondary outcomes included proptosis, CAS, subjective diplopia, and quality-of-life., Results: Thirty-three of 37 placebo-treated OPTIC patients (89.2%) became proptosis responders (mean ± standard deviation, -3.5 ± 1.7 mm) when treated with teprotumumab in OPTIC-X. The responses were equivalent to the OPTIC study. In these responders, proptosis, CAS of 0 or 1, and diplopia responses were maintained in 29 of 32 patients (90.6%), 20 of 21 patients (95.2%), and 12 of 14 patients (85.7%), respectively, at follow-up week 48. The median TED duration was 12.9 months versus 6.3 months in those treated with teprotumumab in the OPTIC study. Of the 5 OPTIC teprotumumab nonresponders re-treated in OPTIC-X, 2 responded, 1 showed a proptosis reduction of 1.5 mm from OPTIC baseline, and 2 discontinued treatment early. Of the OPTIC teprotumumab responders who experienced flare, 5 of 8 patients (62.5%) responded when re-treated (mean proptosis reduction, 1.9 ± 1.2 mm from OPTIC-X baseline and 3.3 ± 0.7 mm from OPTIC baseline). Compared with published double-masked trials and their integrated follow-up, no new safety signals were identified. Mild hearing impairment was reported; 4 events occurred during the first course of treatment, and 2 events reoccurred after re-treatment., Conclusions: Patients with TED of longer disease duration responded similarly to those treated earlier in the disease course. Patients with an insufficient initial response or flare may benefit from additional teprotumumab therapy. No new safety risk was identified; however additional postmarketing pharmacovigilance is ongoing., (Copyright © 2021 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Objective: Thyroid eye disease (TED) is a debilitating autoimmune disease characterized by ocular and periorbital tissue inflammation, proptosis, and visual impairment. The known risk factors for TED include radioactive iodine therapy, female sex, and smoking. The risk factors for severe TED include hyperthyroidism, male sex, smoking, and diabetes; however, little is known about how diabetes mellitus (DM) influences TED. This claims-based analysis examined TED characteristics in patients with and without diabetes., Methods: Symphony database (2010-2015 U.S. claims) was mined for patients with ≥1 Graves' disease diagnosis code and ≥1 TED-associated eye code, including proptosis, strabismus, diplopia, lid retraction, exposure keratoconjunctivitis, and optic neuropathy (ON). DM status was determined based on type 1 or type 2 diabetes coding. Sight-threatening TED was defined as ≥1 ON or exposure keratoconjunctivitis code., Results: A total of 51 220 patients were identified. Of them, 2618 (5.1%) and 12 846 (25.1%) had type 1 and type 2 DM, respectively. Patients with and without DM had similar characteristics, but patients with DM were more often men (type 1: 30.3%, type 2: 28.7% vs no DM: 20.5%; both P < .001) and older at the first TED code. In patients with DM, strabismus (25.4%, 22.6% vs 19.9%) and diplopia (38.6%, 37.9% vs 29.9%) occurred more often but proptosis occurred less often (42.3%, 46.3% vs 58.5%; all P < .001). Sight-threatening TED occurred more often in patients with DM because of higher ON rates., Conclusion: Patients with TED and DM may have more extraocular muscle involvement. Furthermore, the higher prevalence of severe TED stemmed from higher ON rates, possibly associated with diabetes-related vasculopathies. These hypothesis-generating data warrant further exploration., (Copyright © 2021 AACE. Published by Elsevier Inc. All rights reserved.)

Introduction: Thyroid eye disease (TED) is an autoimmune condition producing ocular pain, dysmotility, and ocular structure and function changes. As disease activity changes, redness, swelling, and pain can improve, but eye comfort, appearance, and motility alterations often persist. There are limited data on chronic TED patient-reported outcomes. This study examined chronic US TED patient-reported symptoms and quality of life (QOL)., Methods: Existing data from an online survey regarding chronic TED signs/symptoms and patient QOL were retrospectively examined. The Graves' Ophthalmopathy QOL instrument (GO-QOL; 0-100, 100 = highest QOL) evaluated overall, appearance, and vision-related QOL. Influencing factors were examined by stratifying patients into low (overall QOL ≤ 50), moderate (> 50 and < 75), and high (≥ 75) QOL categories., Results: One hundred patients (47 women, 81 Caucasian, 45.2 ± 7.6 years) were included. The duration of inactive TED was 3.0 ± 4.6 years and total duration of TED was 5.8 ± 5.9 years. Patients reported an average of 20 doctor visits/year and high prevalence of anxiety (34%) and depression (28%). Prior TED treatments for the polled population included systemic corticosteroids during active TED (25%), orbital radiation (5%), and surgery (25%). The overall GO-QOL score was 60.5 ± 21.8 (vision-related: 58.6 ± 24.0, appearance-related: 62.3 ± 25.1). Patients with low QOL more frequently reported hypothyroidism, anxiety, and a larger number of chronic TED signs/symptoms (average: 4.2). Compared to high QOL patients, low QOL patients had more pain (39% vs. 13%), blurry vision (30% vs. 17%), and diplopia (27% vs. 3%, all p ≤ 0.025). Additionally, the low QOL group more often had TED-specific surgical history (45% vs. 10%, p = 0.002), more often reported disability/unemployment (21% vs. 3%, p = 0.055), and had a higher number of doctor visits (40 vs. 5 visits/person/year, p < 0.001)., Conclusion: TED severely impacts patient QOL, despite becoming stable and chronic. Patients reported vision and appearance impairment and psychosocial impact long after acute TED had subsided., (© 2021. The Author(s).)

Introduction: Gout is a common, progressive, systemic inflammatory arthritis caused by hyperuricemia. Current guidelines recommend that serum uric acid (sUA) levels be maintained below 6.0 mg/dl to minimize acute gout attacks, tophi development, and long-term joint and organ damage. This study examined the influence of uncontrolled gout on post-diagnosis comorbidities and medication use., Methods: The Humana Research Database (2007-2016, commercial insurance and Medicare) was searched (PearlDiver tool) for patients who had a gout diagnosis code, claims data for at least 6 months before and after diagnosis, and at least 90 days of continuous urate-lowering therapy within 1 year of diagnosis. Patients with controlled (all sUA measurements < 6.0 mg/dl) and uncontrolled (all sUA measurements ≥ 8.0 mg/dl) gout were further examined and compared to better understand the influence of uncontrolled gout on post-diagnosis comorbidities, medication use, and reasons for seeking medical care., Results: A total of 5473 and 1358 patients met inclusion and classification criteria for the controlled and uncontrolled groups, respectively. Identified comorbidities in both groups included hypertension, hyperlipidemia, diabetes, cardiovascular disease, and chronic kidney disease (CKD). However, the uncontrolled group was more likely to have diabetes, CKD, and cardiovascular disease (including heart failure and atrial fibrillation). Additionally, CKD tended to be more advanced in the uncontrolled gout population (Stage 4-5: 34.6 vs. 22.2%). Overall opioid use was higher in uncontrolled patients., Conclusions: The current study identified differences between controlled and uncontrolled gout patients, including usage of medication, severity of CKD, and prevalence of CKD, diabetes, and heart disease.

Introduction: Thyroid eye disease (TED) is an autoimmune disease that causes retro-orbital inflammation and subsequent proptosis, corneal exposure, strabismus, and variable vision changes. European studies have shown that TED can severely impact quality of life (QOL), but little is known about the QOL of patients with TED in the USA. Given that patient QOL influences TED severity classifications and subsequent treatment, understanding physician-perceived patient QOL is extremely important., Methods: This retrospective chart review (conducted in 2018) examined QOL in US patients with moderate-to-severe TED, as reported by treating physicians who regularly manage patients with TED (≥ 5 patients in prior 12 months). The physicians graded patients' overall QOL (7-point Likert scale; 1 = "not at all impaired", 7 = "extremely impaired"), assessing mental health, vision changes, and ocular structural signs/symptoms. Patient demographics and clinical findings were examined to understand the impact of disease presentation on physician-perceived QOL., Results: Medical record data of 714 US patients with moderate-to-severe TED were provided by 181 physicians (73 endocrinologists, 108 ophthalmologists). Patients had a mean age of 49.4 (standard deviation [SD] 13.6) years, and 102 cases (14%) were severe. Anxiety and/or depression was reported in 36% of patients (an increase from the 18.9% prevalence reported for the USA in 2017 by the US National Institute of Mental Health; P < 0.001). The mean physician-reported QOL impact score was 4.1 (SD 1.5). Furthermore, 62 and 89% of patients with moderate and severe TED, respectively, had a high physician-perceived QOL impact (≥ 4). The higher QOL impact group had significantly higher rates of pain symptoms, visual disturbances (including diplopia), and orbito-facial structural changes. Higher disease activity and severity were associated with lower physician-perceived QOL., Conclusion: Patients' QOL, as evaluated by US physicians, is highly impacted by the activity and severity of TED. Additionally, mental health issues were more frequently reported by patients with TED than in the general US population. Ocular pain, strabismus, and diplopia appear to be main drivers of physician-perceived QOL impairment in this sample of US patients with TED.

Background: The causal relationship between gout and renal transplant outcomes is difficult to assess due to multiple interacting covariates. This study sought to estimate the independent effect of new-onset gout on renal transplant outcomes using a methodology that accounted for these interactions., Methods: This study analyzed data on patients in the US Renal Data System (USRDS) who received a primary kidney transplant between 2008 and 2015. The exposure was new-onset gout, and the primary endpoint was returning to dialysis >12 months postindex date (transplant date). A marginal structural model (MSM) was fitted to determine the relative risk of new-onset gout on return to dialysis., Results: 18 525 kidney transplant recipients in the USRDS met study eligibility. One thousand three hundred ninety-nine (7.6%) patients developed new-onset gout, and 1420 (7.7%) returned to dialysis >12 months postindex. Adjusting for baseline and time-varying confounders via the MSM showed new-onset gout was associated with a 51% increased risk of return to (RR, 1.51; 95% CI, 1.03-2.20)., Conclusions: This finding suggests that new onset gout after kidney transplantation could be a harbinger for poor renal outcomes, and to our knowledge is the first study of kidney transplant outcomes using a technique that accounted for the dynamic relationship between renal dysfunction and gout., (Copyright © 2020 The Author(s). Transplantation Direct. Published by Wolters Kluwer Health, Inc.)

Introduction: Limited data exist on US referral/management patterns for moderate-to-severe thyroid eye disease (TED), a disabling condition., Methods: US ophthalmologists and endocrinologists experienced in treating TED provided medical record data of moderate-to-severe TED patients and information on referral/treatment practices. Data on signs/symptoms, medical/surgical treatments, treatment response, and referral history were collected. Moderate and severe cases were stratified to interrogate treatment/practice differences., Results: A total of 181 physicians provided data on 714 patients (49.4 ± 13.6 years old, 65% women, 14% severe disease). Reporting physicians diagnosed 55% of patients themselves and solely managed 37% of cases, with similar referral/comanagement patterns between moderate and severe cases. Topical therapies included lubricating (79%) and glucocorticoid (39%) eye drops. Systemic therapies included oral glucocorticoids (36%), IV glucocorticoids (15%), and rituximab and/or tocilizumab (12%). Few patients underwent orbital radiation (4%) or surgical intervention (4%). IV glucocorticoids (33% vs. 12%), biologics (26% vs. 10%), orbital radiation (11% vs. 3%), and ocular surgery (12% vs. 3%) were used more often in severe versus moderate cases (all P  < 0.001). However, severe disease was less responsive to therapy (very responsive to therapy: 28% vs. 49%, P  < 0.001)., Conclusions: Participating physicians were primarily responsible for just over one-half of TED diagnoses, but solely treated <40% of patients. Severe TED was treated more often with surgery and systemic immunologic therapies than moderate disease, but was less likely to respond to treatment. These results reinforce that moderate-to-severe TED is difficult to treat with an unmet medical need in the United States., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society.)

Background/aims: Urea cycle disorders (UCDs) are rare inborn errors of urea synthesis. US and European consensus statements on the diagnosis and treatment of UCDs were last published in 2001 and 2019, respectively. Recommendations are based primarily on case reports and expert opinion and there is limited agreement or consistency related to long-term management approaches. A clinician survey was conducted to assess current real-world practices and perspectives on challenges and unmet needs., Methods: A 14-item multiple-choice survey was administered to physicians in 2017. Clinicians who reported actively managing at least 1 patient with UCD were eligible to participate. Descriptive statistics were calculated for each survey item (frequencies for categorical variables; means, standard deviations, medians, and ranges for continuous variables)., Results: Sixty-six US clinicians completed the survey (65 geneticists; 1 pediatric neurologist). Over 90% of responders agreed or strongly agreed that even modest elevations in ammonia could cause physiological and functional brain damage; >80% of respondents agreed that asymptomatic UCD patients are at risk of brain damage over time due to mild/subclinical elevations in ammonia. Eighty-six percent of clinicians agreed or strongly agreed with recommending genetic testing for female relatives when a patient is diagnosed with ornithine transcarbamylase deficiency. Ninety-four percent of respondents agreed that patients have better disease control when they are more adherent to their UCD therapy. Nearly 90% indicated that clinicians and patients would benefit from updated UCD management guidance. More than half (53%) of respondents rated the symptoms of UCDs as extremely or very burdensome to the everyday lives of patients and their families; only 8% rated UCD symptoms as slightly or not at all burdensome. The majority of clinicians agreed (48%) or strongly agreed (32%) that caring for a child or family member with a UCD has a negative impact on the quality of life and/or health of family members/guardians (e.g. stress, relationships, ability to work)., Conclusions: This self-reported survey suggests a need for updated and expanded clinical guidance on the long-term treatment and management of UCD patients., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Juvenile idiopathic arthritis (JIA) is an inflammatory arthritis of unknown etiology, which lasts for greater than 6 weeks with onset before 16 years of age. JIA is the most common chronic rheumatic disease in children. NSAIDs have been the mainstay of initial management with naproxen (NAP) being commonly used, but they may cause serious side effects such as gastric ulcers which can be reduced by concomitant administration of proton pump inhibitors, such as esomeprazole (ESO)., Methods: Primary objective was to evaluate the safety and tolerability of 3 fixed doses of NAP/ESO in JIA patients aged 12 to 16 years. Forty-six children and adolescents with JIA by International League of Associations for Rheumatology criteria, mean age of 13.6 years, from 18 US sites were prospectively enrolled over 2 years and followed for up to 6 months. Doses of the NAP/ESO fixed combination were based on baseline weight. The exploratory efficacy outcome was assessed with the ACR Pediatric-30, - 50, - 70, - 90 Response and the Childhood Health Assessment Questionnaire (CHAQ) discomfort and functional scores at months 1, 3, and 6 as change from baseline. Occurrence and causality were assessed for treatment emergent AEs (TEAEs) and discontinuations were monitored monthly., Results: Forty-six patients received at least 1 dose of naproxen/esomeprazole and 36 completed the trial. Thirty-seven (80.4%) had at least 1 treatment emergent adverse event (TEAE) and, with the exception of 2 events in one patient, all of the TEAEs were mild or moderate. Frequent TEAEs (≥5% of patients) were upper respiratory tract and gastrointestinal related. Eleven (23.9%) had at least 1 TEAE considered to be related to study drug. Four patients (8.7%) discontinued due to a TEAE with one of these being the only serious AE reported, acute hepatitis. Mean number of active joints at baseline was 3.1. Improvement in JIA signs and symptoms occurred at most assessments and by month 6, the percentage of patients with an ACR Pediatric-30, - 50, - 70, and - 90 Response was 47.1, 38.2, 32.4, and 17.6%, respectively. The percent of patients achieving ACR Pediatric response increased over time. CHAQ discomfort improved at each assessment and functional scores improved at all assessments for 'Arising, Walking, and Activities' with several improved for 'Dressing and Grooming, Eating, Hygiene, and Grip'. There was no indication of a dose-related efficacy effect., Conclusion: NAP/ESO was well tolerated in JIA patients aged 12 to 16 years with high levels of response to ACR criteria. No new safety signals were identified for the well-characterized components of this fixed dosed JIA treatment, which was developed to reduce the risk of gastric ulcers., Trial Registration: Clinicaltrials.gov, NCT01544114 . Registered February 21, 2012.

Introduction: Rheumatoid arthritis (RA) produces debilitating morning stiffness. Exogenous glucocorticoids can help with these symptoms when timed appropriately. Bedtime dosing of delayed-release prednisone (DR-prednisone) matches the rise of inflammatory cytokines before awakening and can improve stiffness and other RA symptoms. A prospective open-label study was conducted in patients currently on stable doses of immediate-release prednisone (IR-prednisone) who were switched to DR-prednisone to analyze the incremental benefit of better timed and lower dose glucocorticoid therapy., Methods: Twelve US sites enrolled patients with moderate-severe RA into a 12-week prospective study. Patients were switched from IR- to DR-prednisone while maintaining other existing background therapies. Change from baseline in morning stiffness severity, morning stiffness duration, swollen and tender joint counts (S-TJC), 28 joint disease activity score (DAS28), and patient/physician global assessment (PGA/PhGA), among others, were measured. Post-hoc analyses were performed on those completing 10 weeks of treatment and those with >60 min of morning stiffness at baseline., Results: Fifty-six patients had at least one follow-up visit and were similar in demographics to previous controlled trials with DR-prednisone with regard to baseline age and DAS28-CRP but had lower morning stiffness and RA duration. DR-prednisone produced a trend toward lower morning stiffness severity and duration with a reduction in daily prednisone dose of almost 1 mg. Patients treated with DR-prednisone for ≥10 weeks demonstrated significant reductions in morning stiffness duration, SJC, TJC, DAS28-CRP, and PhGA (all p ≤ 0.04). Patients treated for ≥10 weeks with >60 min of baseline morning stiffness produced similar results in these measures as well as a 21% reduction in morning stiffness severity (p = 0.02)., Conclusion: Patients switched to DR-prednisone from IR-prednisone in this practice-based study maintained or improved their outcomes across a variety of domains, and results were comparable to previous controlled trials in which patients completed at least 10 weeks of treatment., Funding: Horizon Pharma USA, Inc., Trial Registration: ClinicalTrials.gov identifier, NCT02287610.

Microvascular network formation is required for the success of many therapies in regenerative medicine. The process of vessel assembly is fundamentally altered, however, in many people within the potential patient population, including the elderly and people with diabetes. Significant research has been performed to determine how cellular dysfunction contributes to this inadequate neovascularization, but alterations in the extracellular matrix (ECM) may also influence this process. Glycation of ECM proteins, specifically type I collagen, increases as people age and is accelerated due to uncontrolled diabetes. This glycation results in increased ECM stiffness and resistance to degradation. The goal of this research is to determine whether collagen glycation consistent with changes in aged (defined as people older than 80 years old) and diabetic individuals influences neovascularization. Collagen gels that were incubated in glucose-6-phopshate (G6P) for varying times exhibited cross-linking (26.2+/-8.1% and 31.3+/-5.6% for incubation in 375 mM G6P for 5 and 8 days, respectively), autofluorescence, and advanced glycation end product levels (666+/-481 and 2122+/-501 pmol/mg protein for 5 and 8 days of 375 mM G6P, respectively) consistent with aged and diabetic populations. Three-dimensional culture models showed that sprouting angiogenesis was delayed in collagen gels with high levels of glycation. When implanted in vivo, glycated gels were degraded (44.4+/-4.2% and 49.5+/-11.7% nondegraded gel remaining for gels incubated for 5 and 8 days in 375 mM G6P, respectively) and vascularized (75.5+/-32.0 and 73.7+/-23.6 vessels/mm(2)) more slowly than controls (22.3+/-9.9% gel remaining and 133.3+/-31.0 vessels/mm(2)). These results suggest that glycation of collagen can alter neovascularization and may contribute to alterations in vessel assembly observed as people age and due to diabetes., (Published by Elsevier Inc.)

Engineered vascularized adipose tissue could serve as an alternative to traditional tissue reconstruction procedures. Adipose formation occurs in a coordinated fashion with neovascularization. Previous studies have shown that extracellular matrix-based materials supplemented with factors that stimulate neovascularization promote adipogenesis in a number of animal models. The present study examines the ability of fibroblast growth factor (FGF-1) delivered from alginate microbeads to induce neovascularization and adipogenesis in type I collagen gels in a vascular pedicle model of adipose tissue engineering. FGF-1 loaded microbeads stimulated greater vascular network formation in an in vitro 3D co-culture model than a single bolus of FGF-1. In in vivo studies, FGF-1 loaded beads suspended in collagen and implanted in a chamber surrounding the exposed femoral pedicle of a rat resulted in a significant increase in vascular density at 1 and 6 weeks in comparison to bolus administration of FGF-1. Staining for smooth muscle actin showed that over 48% of vessels had associated mural cells. While an increase in neovascularization was achieved, there was less than 3% adipose under any condition. These results show that delivery of FGF-1 from alginate beads stimulated a more persistent neovascularization response than bolus FGF-1 both in vitro and in vivo. However, unlike previous studies, this increased neovascularization did not result in adipogenesis. Future studies need to provide a better understanding of the relationship between neovascularization and adipogenesis in order to design advanced tissue engineering therapies., (2009 Elsevier Ltd. All rights reserved.)

Biomaterials that support adipogenesis could contribute to tissue engineering therapies to be used as alternatives to traditional methods of tissue reconstruction and regeneration. We have recently shown that hydrogels comprised of urea soluble proteins and polysaccharides extracted from adipose tissue promote preadipocyte differentiation in vitro and adipogenesis in vivo. However, it is not clear if these findings result from the adipose tissue source of the extracts or if the technique isolates adipogenic factors from other tissues. The present study investigates whether the application of this technique to dermis samples would provide adipogenic hydrogels. Extracts from dermis assembled into hydrogels by either temperature or pH mechanisms. Both formulations supported preadipocyte differentiation in vitro and vascularized adipose formation in vivo. The temperature formulation of the gels induced more rapid adipose formation than the pH formulation in vivo. Interestingly, in comparison to our previous studies the dermis derived hydrogels had comparable adipogenic properties to adipose gels in vivo but not in vitro. Further study of these materials could lead to insight of the role of specific matrix properties on adipogenesis., ((c) 2009 Wiley Periodicals, Inc.)

Interactions with the extracellular matrix (ECM) play an important role in regulating cell function. Cells cultured in, or on, three-dimensional ECM recapitulate similar features to those found in vivo that are not present in traditional two-dimensional culture. In addition, both natural and synthetic materials containing ECM components have shown promise in a number of tissue engineering applications. Current materials available for cell culture and tissue engineering do not adequately reflect the diversity of ECM composition between tissues. In this paper, a method is presented for extracting solutions of proteins and glycoproteins from soft tissues and inducing assembly of these proteins into gels. The extracts contain ECM proteins specific to the tissue source with low levels of intracellular molecules. Gels formed from the tissue-derived extracts have nanostructure similar to ECM in vivo and can be used to culture cells as both a thin substrate coating and a thick gel. This technique could be used to assemble hydrogels with varying composition depending upon the tissue source, hydrogels for three-dimensional culture, as scaffolds for tissue engineering therapies, and to study cell-matrix interactions.

The use of growth factors for the therapeutic stimulation of neovascularization in regenerative medicine has been extensively investigated, but the inability to control their temporal delivery may limit clinical success. A strategy that delivers continuous therapeutic concentrations of growth factors may increase the protein's efficacy. The present study investigates the ability of sustained delivery of fibroblast growth factor-1 (FGF-1), to induce neovascularization in vivo. Alginate microbeads were synthesized to release active FGF-1 for three weeks. Microbeads loaded with FGF-1 (total amount 150 ng) were implanted into a surgically created omentum pouch in rats and were compared to control empty microbead implants and a single bolus injection of 150 ng of FGF-1 with empty microbead implant. Animals were sacrificed at either 3 or 6 weeks post implantation and omenta were analyzed for vascular density and mural cell interactions. Vascular area for bolus FGF-1 and FGF-1 loaded microbeads was higher than control at 3 weeks. At 6 weeks, vascular density in the group with FGF-1 loaded microbeads was significantly higher than the group with bolus administration of FGF-1, primarily due to an increase in the number of vessels less than 20 microm in diameter. Vascular density in omenta of the group receiving the bolus FGF-1 returned to control levels by 6 weeks. Staining for smooth muscle actin showed that 50% of vessels had associated mural cells. There was a trend of increased mural cell staining at 6 weeks for the FGF-1 loaded beads compared to bolus FGF-1 and control levels. Results in these studies suggest that sustained release of FGF-1 increases the duration of the vascular response in contrast to a bolus injection of FGF-1.

Chronic exposure to reducing sugars due to diabetes, aging, and diet can permanently modify extracellular matrix (ECM) proteins. This non-enzymatic glycosylation, or glycation, can lead to the formation of advanced glycation end products (AGE) and crosslinking of the ECM. This study investigates the effects of glycation on the properties of type I collagen gels. Incubation with glucose-6-phopshate (G6P), a reducing sugar that exhibits similar but more rapid glycation than glucose, modified the biological and mechanical properties of collagen gels. Measures of AGE formation that correlate with increased complications in people with diabetes, including collagen autofluorescence, crosslinking, and resistance to proteolytic degradation, increased with G6P concentration. Rheology studies showed that AGE crosslinking increased the shear storage and loss moduli of type I collagen gels. Fibroblasts cultured on glycated collagen gels proliferated more rapidly than on unmodified gels, but glycated collagen decreased fibroblast invasion. These results show that incubation of type I collagen gels with G6P increases clinically relevant measures of AGE formation and that these changes altered cellular interactions. These gels could be used as in vitro models to study ECM changes that occur in diabetes and aging.