Association of liver function markers and apolipoprotein E ε4 with pathogenesis and cognitive decline in Alzheimer's disease.

Background: Alzheimer's disease (AD) is a complex neurodegenerative disorder influenced by various factors, including liver function, which may impact the clearance of amyloid-ß (Aß) in the brain. This study aimed to explore how the apolipoprotein E (APOE) ε4 allele affects the relationship of liver function markers with AD pathology and cognition. Methods: We analyzed data from two independent cohorts, including 732 participants from the Hallym University Medical Center and 483 from the Alzheimer's Disease Neuroimaging Initiative, each group consisting of individuals with and without the APOE ε4 allele. Cross-sectional analyses evaluated the associations of liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], alkaline phosphatase, total bilirubin, and albumin) with AD diagnosis, amyloid positron emission tomography (PET) burden, and cerebrospinal fluid biomarkers for AD (Aß42, total tau, and phosphorylated tau181) at baseline. Longitudinally, we investigated the associations between these liver enzymes and changes in cognitive performance over the course of a year. Logistic and linear regression models were used to analyze these associations and mediation analyses were conducted to assess whether age and amyloid PET burden mediated these associations. Results: Only in the APOE ε4 carrier group, a high AST to ALT ratio and low ALT levels were significantly associated with AD diagnosis, increased amyloid PET burden, and faster longitudinal decline in cognitive function in both cohorts. In particular, the AST to ALT ratio was associated with cerebrospinal fluid Aß42 levels exclusively in the APOE ε4 carrier group in the Alzheimer's Disease Neuroimaging Initiative cohort but not with phosphorylated tau181 or total tau levels. Moreover, mediation analyses from both cohorts revealed that in the APOE ε4 carriers group, age did not mediate the associations between liver enzymes and AD diagnosis or amyloid PET burden. However, amyloid PET burden partially mediated the association between liver enzymes and AD diagnosis exclusively in the APOE ε4 carriers group. Conclusion: This study provides valuable insights into the significant association of the APOE ε4 allele with liver enzymes and their potential role in Aß-related pathogenesis and cognition in AD. Further research is required to elucidate the underlying mechanisms and potential therapeutic implications of these findings.

Impact of white matter hyperintensity volumes estimated by automated methods using deep learning on stroke outcomes in small vessel occlusion stroke.

Introduction: Although white matter hyperintensity (WMH) shares similar vascular risk and pathology with small vessel occlusion (SVO) stroke, there were few studies to evaluate the impact of the burden of WMH volume on early and delayed stroke outcomes in SVO stroke. Materials and methods: Using a multicenter registry database, we enrolled SVO stroke patients between August 2013 and November 2022. The WMH volume was estimated by automated methods using deep learning (VUNO Med-DeepBrain, Seoul, South Korea), which was a commercially available segmentation model. After propensity score matching (PSM), we evaluated the impact of WMH volume on early neurological deterioration (END) and poor functional outcomes at 3-month modified Ranking Scale (mRS), defined as mRS score >2 at 3 months, after an SVO stroke. Results: Among 1,718 SVO stroke cases, the prevalence of subjects with severe WMH (Fazekas score ≥ 3) was 68.9%. After PSM, END and poor functional outcomes at 3-month mRS (mRS > 2) were higher in the severe WMH group (END: 6.9 vs. 13.5%, p < 0.001; 3-month mRS > 2: 11.4 vs. 24.7%, p < 0.001). The logistic regression analysis using the PSM cohort showed that total WMH volume increased the risk of END [odd ratio [OR], 95% confidence interval [CI]; 1.01, 1.00-1.02, p = 0.048] and 3-month mRS > 2 (OR, 95% CI; 1.02, 1.01-1.03, p < 0.001). Deep WMH was associated with both END and 3-month mRS > 2, but periventricular WMH was associated with 3-month mRS > 2 only. Conclusion: This study used automated methods using a deep learning segmentation model to assess the impact of WMH burden on outcomes in SVO stroke. Our findings emphasize the significance of WMH burden in SVO stroke prognosis, encouraging tailored interventions for better patient care.

Gelatin methacryloyl granular scaffolds for localized mRNA delivery.

mRNA therapy is the intracellular delivery of messenger RNA (mRNA) to produce desired therapeutic proteins. Developing strategies for local mRNA delivery is still required where direct intra-articular injections are inappropriate for targeting a specific tissue. The mRNA delivery efficiency depends on protecting nucleic acids against nuclease-mediated degradation and safe site-specific intracellular delivery. Herein, we report novel mRNA-releasing matrices based on RGD-moiety-rich gelatin methacryloyl (GelMA) microporous annealed particle (MAP) scaffolds. GelMA concentration in aerogel-based microgels (µgels) produced through a microfluidic process, MAP stiffnesses, and microporosity are crucial parameters for cell adhesion, spreading, and proliferation. After being loaded with mRNA complexes, MAP scaffolds composed of 10 % GelMA µgels display excellent cell viability with increasing cell infiltration, adhesion, proliferation, and gene transfer. The intracellular delivery is achieved by the sustained release of mRNA complexes from MAP scaffolds and cell adhesion on mRNA-releasing scaffolds. These findings highlight that hybrid systems can achieve efficient protein expression by delivering mRNA complexes, making them promising mRNA-releasing biomaterials for tissue engineering.

Twin Prime Editing Mediated Exon Skipping/Reinsertion for Restored Collagen VII Expression in Recessive Dystrophic Epidermolysis Bullosa.

Gene editing nucleases, base editors, and prime editors are potential locus-specific genetic treatment strategies for recessive dystrophic epidermolysis bullosa; however, many recessive dystrophic epidermolysis bullosa COL7A1 pathogenic nucleotide variations (PNVs) are unique, making the development of personalized editing reagents challenging. A total of 270 of the ∼320 COL7A1 epidermolysis bullosa PNVs reside in exons that can be skipped, and antisense oligonucleotides and gene editing nucleases have been used to create in-frame deletions. Antisense oligonucleotides are transient, and nucleases generate deleterious double-stranded DNA breaks and uncontrolled mixtures of allele products. We developed a twin prime editing strategy using the PEmax and recently evolved PE6 prime editors and dual prime editing guide RNAs flanking COL7A1 exon 5. Prime editing-mediated deletion of exon 5 with a homozygous premature stop codon was achieved in recessive dystrophic epidermolysis bullosa fibroblasts, keratinocytes, and induced pluripotent stem cells with minimal double-stranded DNA breaks, and collagen type VII protein was restored. Twin prime editing can replace the target exon with recombinase attachment sequences, and we exploited this to reinsert a normal copy of exon 5 using the Bxb1 recombinase. These findings demonstrate that twin prime editing can facilitate locus-specific, predictable, in-frame deletions and sequence replacement with few double-stranded DNA breaks as a strategy that may enable a single therapeutic agent to treat multiple recessive dystrophic epidermolysis bullosa patient cohorts.

Differences in Neuropathology between Nitroglycerin-Induced Mouse Models of Episodic and Chronic Migraine.

Multiple animal models of migraine have been used to develop new therapies. Understanding the transition from episodic (EM) to chronic migraine (CM) is crucial. We established models mimicking EM and CM pain and assessed neuropathological differences. EM and CM models were induced with single NTG or multiple injections over 9 days. Mechanical hypersensitivity was assessed. Immunofluorescence utilized c-Fos, NeuN, and Iba1. Proinflammatory and anti-inflammatory markers were analyzed. Neuropeptides (CGRP, VIP, PACAP, and substance P) were assessed. Mechanical thresholds were similar. Notable neuropathological distinctions were observed in Sp5C and ACC. ACC showed increased c-Fos and NeuN expression in CM (p < 0.001) and unchanged in EM. Sp5C had higher c-Fos and NeuN expression in EM (p < 0.001). Iba1 was upregulated in Sp5C of EM and ACC of CM (p < 0.001). Proinflammatory markers were strongly expressed in Sp5C of EM and ACC of CM. CGRP expression was elevated in both regions and was higher in CM. VIP exhibited higher levels in the Sp5C of EM and ACC of CM, whereas PACAP and substance P were expressed in the Sp5C in both models. Despite similar thresholds, distinctive neuropathological differences in Sp5C and ACC between EM and CM models suggest a role in the EM to CM transformation.

Effects of Prior Metformin Use on Stroke Outcomes in Diabetes Patients with Acute Ischemic Stroke Receiving Endovascular Treatment.

Diabetes mellitus (DM) predisposes individuals to vascular injury, leading to poor outcomes after ischemic stroke and symptomatic hemorrhagic transformation (SHT) after thrombolytic and endovascular treatment (EVT). Metformin (MET), an oral antidiabetic drug, has shown potential neuroprotective effects, but its impact on stroke prognosis in DM patients undergoing EVT remains unclear. In a multicenter study, 231 patients with DM undergoing EVT for acute ischemic stroke were enrolled. Prior MET use was identified, and patients were stratified into MET+ and MET- groups. Demographics, clinical data, and outcomes were compared between groups. Multivariate analysis was used to assess the effect of MET on stroke prognosis. Of the enrolled patients, 59.3% were previously on MET. MET+ patients had lower initial infarct volumes and NIHSS scores compared to MET-taking patients. Multivariate analysis showed that MET+ was associated with a lower risk of stroke progression and SHT (with stroke progression as follows: odd ratio [OR] 0.24, 95% confidence interval [CI] [0.12-0.48], p < 0.001; SHT: OR 0.33, 95% CI [0.14-0.75], p = 0.01) and was also associated with better 3-month functional outcomes (mRS 0-2) after EVT. Prestroke MET use in DM patients undergoing EVT is associated with improved stroke prognosis, including reduced risk of stroke progression and SHT and better functional outcomes. These findings suggest the potential neuroprotective role of MET in this population and highlight its clinical utility as an adjunctive therapy in the management of ischemic stroke. Further research is warranted to elucidate the underlying mechanisms and to optimize MET therapy in this setting.

Effectiveness of endovascular treatment for in-hospital stroke vs. community-onset stroke: a propensity score-matched analysis.

BACKGROUND: The effectiveness of endovascular treatment for in-hospital stroke remains debatable. We aimed to compare the outcomes between patients with in-hospital stroke and community-onset stroke who received endovascular treatment. METHODS: This prospective registry-based cohort study included consecutive patients who underwent endovascular treatment from January 2013 to December 2022 and were registered in the Selection Criteria in Endovascular Thrombectomy and Thrombolytic Therapy study and Yonsei Stroke Cohort. Functional outcomes at day 90, radiological outcomes, and safety outcomes were compared between the in-hospital and community-onset groups using logistic regression and propensity score-matched analysis. RESULTS: Of 1,219 patients who underwent endovascular treatment, 117 (9.6%) had in-hospital stroke. Patients with in-hospital onset were more likely to have a pre-stroke disability and active cancer than those with community-onset. The interval from the last known well to puncture was shorter in the in-hospital group than in the community-onset group (155 vs. 355 min, p<0.001). No significant differences in successful recanalization or safety outcomes were observed between the groups; however, the in-hospital group exhibited worse functional outcomes and higher mortality at day 90 than the community-onset group (all p<0.05). After propensity score matching including baseline characteristics, functional outcomes after endovascular treatment did not differ between the groups (OR: 1.19, 95% CI 0.78-1.83, p=0.4). Safety outcomes did not significantly differ between the groups. CONCLUSION: Endovascular treatment is a safe and effective treatment for eligible patients with in-hospital stroke. Our results will help physicians in making decisions when planning treatment and counseling caregivers or patients.

miR-129-5p as a biomarker for pathology and cognitive decline in Alzheimer's disease.

BACKGROUND: Alzheimer's dementia (AD) pathogenesis involves complex mechanisms, including microRNA (miRNA) dysregulation. Integrative network and machine learning analysis of miRNA can provide insights into AD pathology and prognostic/diagnostic biomarkers. METHODS: We performed co-expression network analysis to identify network modules associated with AD, its neuropathology markers, and cognition using brain tissue miRNA profiles from the Religious Orders Study and Rush Memory and Aging Project (ROS/MAP) (N = 702) as a discovery dataset. We performed association analysis of hub miRNAs with AD, its neuropathology markers, and cognition. After selecting target genes of the hub miRNAs, we performed association analysis of the hub miRNAs with their target genes and then performed pathway-based enrichment analysis. For replication, we performed a consensus miRNA co-expression network analysis using the ROS/MAP dataset and an independent dataset (N = 16) from the Gene Expression Omnibus (GEO). Furthermore, we performed a machine learning approach to assess the performance of hub miRNAs for AD classification. RESULTS: Network analysis identified a glucose metabolism pathway-enriched module (M3) as significantly associated with AD and cognition. Five hub miRNAs (miR-129-5p, miR-433, miR-1260, miR-200a, and miR-221) of M3 had significant associations with AD clinical and/or pathologic traits, with miR129-5p by far the strongest across all phenotypes. Gene-set enrichment analysis of target genes associated with their corresponding hub miRNAs identified significantly enriched biological pathways including ErbB, AMPK, MAPK, and mTOR signaling pathways. Consensus network analysis identified two AD-associated consensus network modules and two hub miRNAs (miR-129-5p and miR-221). Machine learning analysis showed that the AD classification performance (area under the curve (AUC) = 0.807) of age, sex, and APOE ε4 carrier status was significantly improved by 6.3% with inclusion of five AD-associated hub miRNAs. CONCLUSIONS: Integrative network and machine learning analysis identified miRNA signatures, especially miR-129-5p, as associated with AD, its neuropathology markers, and cognition, enhancing our understanding of AD pathogenesis and leading to better performance of AD classification as potential diagnostic/prognostic biomarkers.

Effect of pre-stroke antiplatelet use on stroke outcomes in acute small vessel occlusion stroke with moderate to severe white matter burden.

BACKGROUND: Cerebral small vessel disease is characterized by white matter hyperintensities (WMH) and acute small vessel occlusion (SVO) stroke. We investigated the effect of prior antiplatelet use (APU) on stroke outcome in 1151 patients with acute SVO stroke patients and moderate to severe WMH. METHODS: Using a multicenter database, this retrospective study used quantitative WMH volume measurements and propensity score matching (PSM) for comparisons between patients with prior APU and without APU. Primary outcomes were stroke progression and poor functional outcome (modified Rankin Scale>2) at 3 months. Logistic regression analyses assessed associations between prior APU, WMH burden, and stroke outcomes. RESULTS: Stroke progression was lower in the prior APU group in both the total cohort (14.8% vs. 6.9%, p < 0.001) and the PSM cohort (16.3% vs. 6.9%, p < 0.001). The proportion of poor functional outcomes at 3 months was not significantly different in the total cohort, but the PSM cohort showed a lower proportion in the prior APU group (30.8% vs. 20.2%, p = 0.002). Logistic regression analysis confirmed that prior APU was associated with a reduced risk of stroke progression (OR, 0.39; 95% CI, 0.22-0.70; p = 0.001) and poor functional outcome at 3 months (OR, 0.37; 95% CI, 0.23-0.59; p < 0.001). CONCLUSION: Prior APU is associated with reduced stroke progression and improved functional outcome at 3 months in acute SVO stroke patients with moderate to severe WMH. Early treatment of WMH and acute SVO stroke may have potential benefits in improving stroke outcomes.

Deep Learning-Based Knee MRI Classification for Common Peroneal Nerve Palsy with Foot Drop.

Foot drop can have a variety of causes, including the common peroneal nerve (CPN) injuries, and is often difficult to diagnose. We aimed to develop a deep learning-based algorithm that can classify foot drop with CPN injury in patients with knee MRI axial images only. In this retrospective study, we included 945 MR image data from foot drop patients confirmed with CPN injury in electrophysiologic tests (n = 42), and 1341 MR image data with non-traumatic knee pain (n = 107). Data were split into training, validation, and test datasets using a 8:1:1 ratio. We used a convolution neural network-based algorithm (EfficientNet-B5, ResNet152, VGG19) for the classification between the CPN injury group and the others. Performance of each classification algorithm used the area under the receiver operating characteristic curve (AUC). In classifying CPN MR images and non-CPN MR images, EfficientNet-B5 had the highest performance (AUC = 0.946), followed by the ResNet152 and the VGG19 algorithms. On comparison of other performance metrics including precision, recall, accuracy, and F1 score, EfficientNet-B5 had the best performance of the three algorithms. In a saliency map, the EfficientNet-B5 algorithm focused on the nerve area to detect CPN injury. In conclusion, deep learning-based analysis of knee MR images can successfully differentiate CPN injury from other etiologies in patients with foot drop.

Association of Serum Liver Enzymes with Brain Amyloidopathy and Cognitive Performance.

Background: Alzheimer's disease (AD) is characterized by amyloid-ß (Aß) plaque accumulation and neurofibrillary tangles in the brain. Emerging evidence has suggested potential interactions between the brain and periphery, particularly the liver, in regulating Aß homeostasis. Objective: This study aimed to investigate the association of serum liver enzymes with brain amyloidopathy and cognitive performance in patients with complaints of cognitive decline. Methods: A total of 1,036 patients (mean age 74 years, 66.2% female) with subjective cognitive decline, mild cognitive impairment, AD dementia, and other neurodegenerative diseases were included using the Smart Clinical Data Warehouse. Amyloid positron emission tomography (PET) imaging, comprehensive neuropsychological evaluations, and measurements of liver enzymes, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, total bilirubin, and albumin, were assessed. After propensity score matching, logistic and linear regression analyses were used to investigate the associations between liver enzymes, amyloid status, and cognitive performance. Additionally, a machine learning approach was used to assess the classification performance of liver enzymes in predicting amyloid PET positivity. Results: Lower ALT levels and higher AST-to-ALT ratios were significantly associated with amyloid PET positivity and AD diagnosis. The AST-to-ALT ratio was also significantly associated with poor memory function. Machine learning analysis revealed that the classification performance of amyloid status (AUC = 0.642) for age, sex, and apolipoprotein E ɛ4 carrier status significantly improved by 6.2% by integrating the AST-to-ALT ratio. Conclusions: These findings highlight the potential association of liver function on AD and its potential as a diagnostic and therapeutic implications.

Experimental model of obtaining tissue adipose, mesenchymal stem cells isolation and distribution in surgery flaps in rats

PURPOSE: To investigate the experimental model for obtaining adipose tissue, isolation, characterization of mesenchymal stem cells and evaluation of their distribution in the tram flap in rats. METHODS: Five rats of Wistar were randomly assigned to two groups. In group I, three animals underwent removal of adipose tissue in the groin procedure to establish the experimental model and obtain a cell lineage. The animals of group II (n = 2) underwent surgical flap procedure, and satisfaction injection of mesenchymal stem cells pretreated with marker fluorescente. RESULTS: obtaining adipose tissue of the inguinal region of the rat proved to be possible. The isolated cells were characterized as mesenchymal stem cells and fluorescence microscopy showed the presence of multiple cells arranged around blood vessels and capillaries. CONCLUSION: It was possible to establish an experimental model for obtaining adipose tissue for isolation of mesenchymal stem cells and their distribution in the TRAM flap in rats. .

Isquemia de membros inferiores: perspectiva atual da terapia celular e terapia gênica / Lower limb ischemia: current outlook for cell therapy and gene therapy

O estágio dos sintomas do paciente com doença isquêmica de membros inferiores determina o tipo detratamento. Apesar das terapias já conhecidas um grupo desses pacientes não é candidato ao tratamento cirúrgicoou continua com dor mesmo após o tratamento, o que afeta a sua qualidade de vida. O entendimento dosmecanismos moleculares envolvidos no desenvolvimento vascular possibilita respeitar e compreender os benefíciose limites das terapias moleculares para o tratamento das doenças isquêmicas de membros inferiores. Neste artigodescreve-se a perspectiva atual da terapia celular e da terapia gênica no tratamento da isquemia crítica demembros inferiores.

Comparação do efeito antiangiogênico do ranibizumab e do bevacizumab in vitro / Comparison of anti-angiogenic effect in vitro between ranibizumab and bevacizumab

Objetivo: Comparar o efeito anti-angiogênico in vitro do Bevacizumab e do Rani bizumab. Métodos: Células endotelias venosas de cordão umbilical (ECV304), cultivadas em meio F12 com adição de 10 por cento de soro fetal bovino, foram plaqueadas e tratadas com concentrações clinicamente relevantes de Bevacizumab e Ranibizumab. As drogas foram administradas logo após risco realizado no meio da cultura (metodologia de scratch). Medidas lineares do espaço livre de proliferação celular foram realizadas 24, 48 e 72 horas após o momento da realização do risco. Todos os experimentos foram realizados em triplicata e a análise estatística foi feita pelo teste T-student. Resultados: O efeito inibitório foi observado em ambas as drogas, apenas nas concentrações 0,5 e 0,7 mg/ml. Na concentração 0,7 mg/ml, o Ranibizumab demonstrou efeito inibitório maior do que o Bevacizumab. Na mesma concentração, o Ranibizumab foi três vezes mais potente que o Bevacizumab. O efeito inibitório foi observado apenas nas primeiras 24 horas para ambas as drogas. Conclusão: O Ranibizumab demonstrou efeito maior quando comparado com o Bevacizumab, porém tal efeito está mais relacionado à diferença na razão molar das drogas do que relacionada com uma diferença real no efeito anti-proliferativo.

Purpose: To evaluate the comparative in-vitro antiangiogenic effect of Bevacizumab and Ranibizumab. Methods: Endothelial venous umbilical cells culture (ECV304) cultivated in F12 media with addition of 10 percent Fetal Bovine Serum, were plaqued and treated with clinically relevant concentrations of Bevacizumab and Ranibizumab just after the scratch done in the middle of the culture (scratch methodology). Measurements of the linear size of the area free of cell proliferation were done 24, 48 and 72 hours after the scratch day point. All the experiments were done in triplicate and statistical analysis were done with T-student test. Results: Inhibitory effect was observed just at the concentrations of 0.5 and 0.7 mg/ml in both drugs. At 0.7 mg/ml, Ranibizumab demonstrated a more potent proliferative inhibitory effect than Bevacizumab. At the same concentration, Ranibizumab was three times more potent than Ranibizumab. Inhibitory effect was observed just in the first 24 hours for both drugs. Conclusion: Ranibizumab demonstrates an increased effect when compared to Bevacizumab and this is related more to the different molar rate of each drug than related to a real better proliferative inhibitory effect.

Terapia gênica para osteoporose / Gene therapy for osteoporosis

A osteoporose é considerada um dos problemas de saúde mais comuns e sérios da população idosa mundial. É uma doença crônica e progressiva, caracterizada pela diminuição da massa óssea e deterioração da microarquitetura do tecido ósseo. A terapia gênica representa uma nova abordagem para o tratamento da osteoporose e tem como princípio devolver a função comprometida pelo metabolismo. Esta revisão visa focar os trabalhos relevantes desenvolvidos nos últimos anos, disponibilizados nas bases de dados médicas, e que utilizaram a terapia gênica para o tratamento da osteoporose em modelos animais, bem como, as perspectivas futuras desta terapia. A maioria dos estudos utiliza os genes BMPs, PTH e OPG na tentativa de restabelecer a massa óssea. Apesar da carência de novas moléculas, todos os genes empregados nos estudos se mostraram eficientes no tratamento da doença. Os benefícios que a terapia gênica proporcionará aos pacientes no futuro devem contribuir substancialmente para o aumento na qualidade de vida dos idosos. Em breve, protocolos clínicos envolvendo humanos irão beneficiar os indivíduos com osteoporose.

Osteoporosis is considered one of the most common and serious problems affecting the elderly population worldwide. It is a chronic and progressive disease, characterized by decreased bone mass and degeneration of the microarchitecture of the bone tissue. Gene therapy represents a new approach in osteoporosis treatment, and its main function is to restore the compromised function in the metabolism. This review aims to elucidate the main studies on gene therapy in recent years, in the medical databases, that use gene therapy for the treatment of osteoporosis in animal models, as well as the future prospects of this therapy. The majority of the studies use the BMP, PTH and OPG genes, in an attempt to reestablish bone mass. Despite the lack of new molecules, all genes employed in these studies have proven to be efficient in the treatment of the disease. The benefits that gene therapy will provide for patients in the future should contribute substantially to increasing the quality of life for the elderly. Soon, clinical trials involving humans will benefit individuals with osteoporosis.

Terapia gênica com VEGF para angiogênese na angina refratária: ensaio clínico fase I/II / VEGF gene therapy for angiogenesis in refractory angina: phase I/II clinical trial

OBJETIVO: Avaliar a segurança, viabilidade e efeitos iniciais, clínicos e sobre a perfusão miocárdica, da administração intramiocárdica, transtorácica, de VEGF 165 plasmidial em pacientes com doença arterial coronariana avançada e angina refratária, não passíveis de revascularização percutânea e cirúrgica. MÉTODOS: Ensaio clínico fase I/II. Treze pacientes cardiopatas isquêmicos com angina refratária apesar de tratamento medicamentoso máximo por no mínimo seis meses, não passíveis de revascularização cirúrgica ou por cateter foram submetidos a injeções intramiocárdicas de 2000µg VEGF 165 plasmidial. Os pacientes foram avaliados por cintilografia miocárdica, teste ergométrico, questionário de qualidade de vida (Minnesota) e determinação das classes de insuficiência cardíaca (NYHA) e angina (CCS). RESULTADOS: Não houve óbitos ou reintervenções. Durante o período de tratamento medicamentoso máximo, não se observou diferenças em cintilografias miocárdicas, testes ergométricos e questionários de qualidade de vida, ainda, houve tendência a piora das classes NYHA (P=0,05) e CCS (P=0,05). Três meses após intervenção, observou-se melhora dos escores cintilográficos SSS (18,38±7,51 vs. 15,31±7,29, P=0,003) e SRS (11,92±7,49 vs. 8,53±6,68, P=0,002), porém não na proporção da extensão da área de miocárdio isquêmico (23,38±13,12 por cento vs. 20,08±13,88 por cento, P=0,1). Houve tendência a melhora dos METs nas ergometrias (7,66±4,47 vs. 10,29±4,36, P=0,08), melhora do escore de qualidade de vida (48,23±18,35 vs. 30,15±20,13; P=0,02) e das classes NYHA (3,15±0,38 vs. 1,77±0,83, P=0,001) e CCS (3,08±0,64 vs. 1,77±0,83, P=0,001), no mesmo período. CONCLUSÕES: A terapia demonstrou-se segura e viável nesta série de pacientes. Os resultados iniciais tendem a demonstrar melhora na gravidade da angina e redução da intensidade da isquemia miocárdica.

OBJECTIVE: Safety, feasibility and early myocardial angiogenic effects evaluation of transthoracic intramyocardial phVEGF165 administration for refractory angina in no option patients. METHODS: Cohort study, in which 13 patients with refractory angina under optimized clinical treatment where included, after cineangiograms had been evaluated and found unfeasible by surgeon and interventional cardiologist. Intramyocardial injections of 5mL solution containing plasmidial VEGF165 where done over the ischemic area of myocardium identified by previous SPECT/Sestamibi scan. Evaluations included a SPECT scan, stress test, Minnesotta QOL questionnaire and NYHA functional class and CCS angina class determinations. RESULTS: There were no deaths or new interventions during the study period. There were no significant variations in SPECT scans, QOL scores and stress tests results during medical treatment in the included patients. After the 3rd post operative month, there was improvement in SPECT segmental scores, SSS (18.38±7.51 vs. 15.31±7.29, P=0.003) and SRS (11.92±7.49 vs. 8.53±6.68, P=0.002). The ischemic area extension, however, had non-significant variation (23.38±13.12 percent vs. 20.08±13.88 percent, P=0.1). Stress tests METs varied from 7.66±4.47 pre to 10.29±4.36 METs post-op (P=0.08). QOL score improved from 48.23±18.35 pre to 30.15±20.13 post-op points (P=0.02). NYHA class was 3.15±0.38 pre vs. 1.77±0.83 post-op (P=0.001) and angina CCS class, 3.08±0.64 vs. 1.77±0.83 (P=0.001). CONCLUSIONS: Intramyocardial VEGF165 therapy for refractory angina, in this small trial of no option patients, resulted feasible and safe. Early clinical and scintilographic data showed improvements in symptoms and myocardial perfusion, with regression of ischemia severity in treated areas.

Células-tronco mesenquinais: células ideais para a regeneração cardíaca? / Mesenchymal stem cell: are they appropriate for cardiac regeneration?

As células-tronco mesenquinais representam uma rara subpopulação das células-tronco da medula óssea (<0,01 por cento das células mononucleares da medula óssea) com capacidade de expansão mitótica in vitro. Em decorrência da facilidade em se dividir e proliferar, concluiu-se que as células-tronco mesenquinais seriam as células responsáveis pela manutenção e renovação dos tecidos mesenquinais adultos, incluindo o músculo cardíaco. Esse tipo celular apresenta como uma de suas virtudes considerável atividade imunosupressora. evitando assim efeitos adversos relacionados a rejeição entre o material infundido e o hospedeiro. As células-tronco mesenquinais vêm sendo cada vez mais estudadas, tanto em ensaios pré-clínicos como clínicos. Acreditamos que, superados alguns desafios em seu isolamento, preparo e modo de infusão, essas células poderão, em futuro próximo, representar o tipo celular ideal para a regeneração cardíaca.

Mesenchymal stem cells represent a rare subpopulation of bone marrow stem cells (< 0.01% of mononuclear cells originated from bone marrow) with capacity for in vitro mitotic expansion. Because they split and proliferate easily, mesenchymal stem cells are believed to be responsible for the maintenance and renovation of adult mesenchymal tissues, including the cardiac muscle. One of the virtues of this type of cell is their immunosuppressive activity, avoiding therefore the adverse events related to graft rejection by the host (graft versus host disease). Mesenchymal stem cells have been extensively studied, both in pre-clinical and clinical trials. We believe that once some challenges regarding their isolation, preparation and mode of delivery are overcome, these cells may, in the near future, represent the ideal cell type for cardiac regeneration.

Terapia gênica em distrofias hereditárias de retina / Gene therapy for inherited retinal dystrophies

As distrofias hereditárias de retina abrangem um amplo número de doenças caracterizadas por lenta e progressiva degeneração da retina. São o resultado de mutações em genes expressos em fotorreceptores e no epitélio pigmentado da retina. A herança pode ser autossômica dominante, autossômica recessiva, ligada ao X recessiva, digênica ou herança mitocondrial. Atualmente não há tratamento para essas doenças e os pacientes convivem com a perda progressiva da visão. O aconselhamento genético e o suporte para reabilitação têm indicação nestes casos. Pesquisas envolvendo a base molecular e genética dessas doenças está continuamente em expansão e ampliam as perspectivas para novas formas de tratamento. Dessa forma, a terapia gênica, que consiste na inserção de material genético exógeno em células de um indivíduo com finalidade terapêutica, tem sido a principal forma de tratamento para as distrofias hereditárias de retina. O olho é um órgão peculiar para a terapia gênica, pois é anatomicamente dividido em compartimentos, imunologicamente privilegiado e com meios transparentes. A maioria das doenças oculares tem defeitos em genes conhecidos. Além disso, há modelo animal bem caracterizado para algumas condições. Propostas para pesquisa clínica em terapia gênica nas degenerações retinianas hereditárias com defeito no gene RPE65, recentemente tiveram aprovação ética e os resultados preliminares obtidos trouxeram grandes expectativas na melhora da qualidade de vida dos pacientes.

The inherited retinal dystrophies comprise a large number of disorders characterized by a slow and progressive retinal degeneration. They are the result of mutations in genes that express in either the photoreceptor cells or the retinal pigment epithelium. The mode of inheritance can be autosomal dominant, autosomal recessive, X linked recessive, digenic or mitochondrial DNA inherited. At the moment, there is no treatment for these conditions and the patients can expect a progressive loss of vision. Accurate genetic counseling and support for rehabilitation are indicated. Research into the molecular and genetic basis of disease is continually expanding and improving the prospects for rational treatments. In this way, gene therapy, defined as the introduction of exogenous genetic material into human cells for therapeutic purposes, may ultimately offer the greatest treatment for the inherited retinal dystrophies. The eye is an attractive target for gene therapy because of its accessibility, immune privilege and translucent media. A number of retinal diseases affecting the eye have known gene defects. Besides, there is a well characterized animal model for many of these conditions. Proposals for clinical trials of gene therapy for inherited retinal degenerations owing to defects in the gene RPE65, have recently received ethical approval and the obtained preliminary results brought large prospects in the improvement on patient's quality of life.

A potencialidade dos lentivetores na terapia gênica / The potentiality of lentivectors in gene therapy

Os lentivírus, bem como os oncovírus e os spumavírus, pertencem à família Retroviridae. Essa família possui genoma composto por duas fitas simples de RNA e enzima transcriptase reversa. Os vírus de imunodeficiência humana (HIV), felina (FIV) e simiana (SIV) são os representantes mais bem conhecidos dos lentivírus, devido aos seus efeitos patológicos. O genoma dos lentivírus apresenta uma organização mais complexa do que dos oncovírus e muitos dos seus processos moleculares já estão descritos OU já são conhecidos. Além disso, são capazes de infectar inclusive células quiescentes, características essa que se opõe ao tropismo dos oncovírus. Essas propriedades levaram ao desenvolvimento de vetores lentivirais para terapia gênica e a perspectiva do emprego terapêutico dos mesmos na clínica – por exemplo, para síndrome da imunodeficiência adquirida (SIDA). Uma série de modificações de engenharia genética no lentivetor baseado em HIV levou ao desenvolvimento do primeiro protocolo clínico de terapia gênica lentiviral contra a SIDA, nos EUA. Atualmente, existem vários protocolos clínicos com lentivetores em andamento, seguindo a tendência de empregá-los também em outras doenças.(AU)

Lentivirus, oncovirus and spumavirus belong to the Retroviridae family. The genome of this family is composed of two single strands of RNA and reverse transcriptase enzyme. The human, feline and simian immunodeficiency virus (HIV, FIV, SIV) are well known lentivirus in our society due to their pathological effects. The Lentiviral genome is more complex than the oncovira and much of its molecular mechanisms are already known. In addition, they are able to infect also quiescent cells, in opposition to oncovirus tropism. These properties lead to the development of gene therapy lentiviral vectors and to their possible therapeutic use at clinical level – acquired immunodeficiency syndrome (AIDS), for example. After intense genetic engineering, a HIV based lentivector was first used in a clinical trial in a gene therapy protocol for AIDS, in USA. Currently, there are several clinical trials in progress using lenviral vectors, following the tendency of evaluating their potential to treat many other diseases.(AU)