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Redifferentiation therapy with Dabrafenib (a BRAF inhibitor) and Trametinib (a MEK inhibitor) restores radioiodine avidity of radioiodine-refractory papillary thyroid carcinoma (PTC). A 50-year-old man was diagnosed with radioiodine-refractory PTC pulmonary metastasis post prior total thyroidectomy and radioiodine ablation. The patient was treated with Dabrafenib and Trametinib, followed by second radioiodine ablation with I-131 sodium iodine. Diffuse increased radioiodine uptake by pulmonary metastasis was visualized on post ablation whole body scan. Response to second radioiodine ablation was demonstrated by decrease in size of pulmonary nodules seen on chest CT, along with decrease of thyroglobulin level.
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The percent global glomerulosclerosis is a key factor in determining the outcome of renal transfer surgery. At present, the rate is typically computed by pathologists, which is labour intensive and nonstandardized. With the development of Deep Learning (DL), DL-based segmentation models can be used to better identify and segment normal and sclerosed glomeruli. Based on this, we can better quantify percent global glomerulosclerosis to reduce the discard rate of donor kidneys. We used 51 whole slide images (WSIs) from different institutions that are publicly available on the internet. However, the number of sclerosed glomeruli is much smaller than that of normal glomeruli in different WSIs, which can reduce the effectiveness of Deep Learning. For better sclerosed glomerular identification and segmentation performance, we modified and trained a GAN (generative adversarial network)-based image inpainting model to obtain more synthetic sclerosed glomeruli. Our proposed inpainting method achieved an average SSIM (Structural Similarity) of 0.8086 and an average PSNR (Peak Signal-to-Noise Ratio) of 22.8943 dB in the area of generated sclerosed glomeruli. We obtained sclerosed glomerular segmentation performance improvement by adding synthetic sclerosed glomerular images and achieved the best Dice of glomerular segmentation in different test sets based on the modified Unet model.
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Enfermedades Renales , Trabajo de Parto , Embarazo , Femenino , Humanos , Glomérulos Renales/diagnóstico por imagen , Enfermedades Renales/diagnóstico por imagen , Internet , PatólogosAsunto(s)
Plantas , Proteínas , Sistema Libre de Células , Proteínas/metabolismo , Plantas/metabolismoRESUMEN
Osmotic stress imposed by drought and high salinity inhibits plant growth and crop yield. However, our current knowledge on the mechanism by which plants sense osmotic stress is still limited. Here, we identify the transcriptional regulator SEUSS (SEU) as a key player in hyperosmotic stress response in Arabidopsis. SEU rapidly coalesces into liquid-like nuclear condensates when extracellular osmolarity increases. The intrinsically disordered region 1 (IDR1) of SEU is responsible for its condensation. IDR1 undergoes conformational changes to adopt more compact states after an increase in molecular crowding both in vitro and in cells, and two predicted α-helical peptides are required. SEU condensation is indispensable for osmotic stress tolerance, and loss of SEU dramatically compromises the expression of stress tolerance genes. Our work uncovers a critical role of biomolecular condensates in cellular stress perception and response and expands our understanding of the osmotic stress pathway.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Presión Osmótica , Estrés Fisiológico , Plantas Modificadas Genéticamente/metabolismoRESUMEN
Copper is required for cancer cell proliferation and tumor angiogenesis. Radioactive copper-64 chloride (64CuCl2) is a useful radiotracer for cancer imaging with position emission tomography (PET) based on increased cellular uptake of copper mediated by human copper transporter 1 (hCtr1) expressed on cancer cell membrane. Significant progress has been made in research of using 64CuCl2 as a radiotracer for cancer imaging with PET. Radiation dosimetry study in humans demonstrated radiation safety of 64CuCl2. Recently, 64CuCl2 was successfully used for PET imaging of prostate cancer, bladder cancer, glioblastoma multiforme (GBM), and non-small cell lung carcinoma in humans. Based on the findings from the preclinical research studies, 64CuCl2 PET/CT also holds potential for diagnostic imaging of human hepatocellular carcinoma (HCC), malignant melanoma, and detection of intracranial metastasis of copper-avid tumors based on low physiological background of radioactive copper uptake in the brain. Copper-64 radionuclide emits both ß+ and ß- particles, suggesting therapeutic potential of 64CuCl2 for radionuclide cancer therapy of copper-avid tumors. Recent progress in production of therapeutic copper-67 radionuclide invites clinical research in use of theranostic pair of 64CuCl2 and 67CuCl2 for cancer imaging and radionuclide therapy.
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A 29-year-old male with a history of Hodgkin's lymphoma presented for evaluation of response to chemotherapy with positron emission tomography/computed tomography using fluorine-18-fluoro-2-deoxy-d-glucose (18F-FDG PET/CT). Follow-up 18F-FDG PET/CT imaging demonstrated resolution of previously noted FDG avid axillary lymphadenopathy. However, multiple opacities with increased FDG uptake were noted in the lungs bilaterally, which were suspicious for pulmonary infection, including viral pneumonia. The patient tested positive for coronavirus disease 2019 (COVID-19) virus infection by reverse transcription-polymerase chain reaction (RT-PCR). Additional cycles of chemotherapy were delayed until the patient became negative for COVID-19 virus infection on follow-up RT-PCR test 2 weeks later. The patient received two additional cycles of chemotherapy. Follow-up 18F-FDG PET/CT post chemotherapy demonstrated a decrease in the size of the previously seen mediastinal lymphadenopathy, reduction of FDG uptake by the previously seen mediastinal lymphadenopathy, and reduction of FDG uptake by the previously seen pulmonary opacities, at 2 months after COVID-19 diagnosis. The findings of this case report demonstrated the importance of recognition of pulmonary abnormalities caused by COVID-19 pneumonia on 18F-FDG PET/CT imaging for clinical management of patients with lymphoma.
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BACKGROUND/AIM: Knockdown of human copper transporter 1 has been associated with reduction in copper uptake and suppression of prostate cancer cell proliferation and tumor growth. This study evaluated the effects of steroid-based compounds on copper uptake and proliferation of prostate cancer cells based on their anticancer activity and previous docking analysis of steroid-based copper transporter 1 inhibitors. MATERIALS AND METHODS: We synthesized several new steroid-based compounds and used 64Cu uptake assay and copper quantification assay with inductively coupled plasma mass spectrometry to study their effects on the cellular copper uptake by prostate cancer cells. Additionally, we used CCK-8 cell proliferation assay to study their effects on the proliferation of prostate cancer cells. RESULTS: Significant reduction in cellular copper uptake was observed in the prostate cancer cells treated with these new steroid-based compounds. Moreover, proliferation of prostate cancer cells was suppressed by treatment with the steroid-based compound 6, which had the strongest copper uptake inhibition activity. CONCLUSION: Reduction in copper uptake and inhibition of cell proliferation were demonstrated in prostate cancer cells treated with the new steroid-based compounds synthesized in this study. Steroid-based copper transporter 1 inhibitors may become novel anticancer drugs for targeted anti-copper therapy of prostate cancer and other copper hypermetabolic cancers.
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Antineoplásicos/farmacología , Cobre/metabolismo , Esteroides/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Transporte Biológico/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Técnicas de Química Sintética , Cobre/química , Transportador de Cobre 1/metabolismo , Humanos , Masculino , Estructura Molecular , Neoplasias de la Próstata/metabolismo , Análisis Espectral , Esteroides/química , Relación Estructura-ActividadRESUMEN
Background: This study aimed to cluster newly diagnosed patients and patients with long-term diabetes and to explore the clinical characteristics, risk of diabetes complications, and medication treatment related to each cluster. Research Design and Methods: K-means clustering analysis was performed on 1,060 Chinese patients with type 2 diabetes based on five variables (HbA1c, age at diagnosis, BMI, HOMA2-IR, and HOMA2-B). The clinical features, risk of diabetic complications, and the utilization of elven types of medications agents related to each cluster were evaluated with the chi-square test and the Tukey-Kramer method. Results: Four replicable clusters were identified, severe insulin-resistant diabetes (SIRD), severe insulin-deficient diabetes (SIDD), mild obesity-related diabetes (MOD), and mild age-related diabetes (MARD). In terms of clinical characteristics, there were significant differences in blood pressure, renal function, and lipids among clusters. Furthermore, individuals in SIRD had the highest prevalence of stages 2 and 3 chronic kidney disease (CKD) (57%) and diabetic peripheral neuropathy (DPN) (67%), while individuals in SIDD had the highest risk of diabetic retinopathy (32%), albuminuria (31%) and lower extremity arterial disease (LEAD) (13%). Additionally, the difference in medication treatment of clusters were observed in metformin (p = 0.012), α-glucosidase inhibitor (AGI) (p = 0.006), dipeptidyl peptidase 4 inhibitor (DPP-4) (p = 0.017), glucagon-like peptide-1 (GLP-1) (p <0.001), insulin (p <0.001), and statins (p = 0.006). Conclusions: The newly diagnosed patients and patients with long-term diabetes can be consistently clustered into featured clusters. Each cluster had significantly different patient characteristics, risk of diabetic complications, and medication treatment.
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Presión Sanguínea/fisiología , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/fisiopatología , Neuropatías Diabéticas/fisiopatología , Riñón/fisiopatología , Adulto , Anciano , China , Análisis por Conglomerados , Estudios Transversales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Masculino , Metformina/uso terapéutico , Persona de Mediana Edad , Factores de RiesgoRESUMEN
AIMS: Diabetes mellitus is a risk factor for Parkinson's disease. These diseases share similar pathogenic pathways, such as mitochondrial dysfunction, inflammation, and altered metabolism. Despite these similarities, the pathogenic relationship between these two diseases is unclear. [18F]FP-(+)-DTBZ is a promising radiotracer targeting VMAT2, which has been used to measure ß-cell mass and to diagnose Parkinson's disease. The aim of this study was to examine the effect of type 1 diabetes on VMAT2 expression in the striatum using [18F]FP-(+)-DTBZ. MATERIALS AND METHODS: A longitudinal study of type 1 diabetic rats was established by intraperitoneally injecting male Wistar rats with streptozotocin. Rats injected with saline were used as the control group. Glucose level, body weight, and [18F]FP-(+)-DTBZ uptake in the striatum and pancreas were evaluated at 0.5, 1, 4, 6 and 12 months after STZ or saline injection. RESULTS: At one-half month post-STZ injection, the glucose levels in these rats increased and then returned to a normal level at 6 months. Along with increased glucose levels, body weight was also decreased significantly and returned slowly to a normal level. ß-Cell mass and striatal [18F]FP-(+)-DTBZ uptake were impaired significantly at 2 weeks post-STZ injection in type 1 diabetic rats and returned to a normal level at 6 and 4 months post-STZ injection. CONCLUSIONS: Due to increased glucose levels and decreased ß-cell mass, decreased [18F]FP-(+)-DTBZ uptake in the striatum was observed in type 1 diabetic rats. Decreased BCM and increased glucose levels were correlated with VMAT2 expression in the striatum which indicated DM is a risk factor for PD.
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Diabetes Mellitus Tipo 1/diagnóstico por imagen , Diabetes Mellitus Tipo 1/metabolismo , Regulación de la Expresión Génica , Neostriado/diagnóstico por imagen , Neostriado/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones , Proteínas de Transporte Vesicular de Monoaminas/metabolismo , Animales , Glucemia/metabolismo , Peso Corporal , Diabetes Mellitus Tipo 1/sangre , Modelos Animales de Enfermedad , Estudios Longitudinales , Masculino , Ratas , Ratas WistarRESUMEN
A 74-year-old man presented with rapid rising prostate-specific antigen (PSA) 2 years after treatment of prostate cancer with prostatectomy and salvage radiation therapy. PSA increased from 923 to 4349 ng/mL within 2 months. No osseous metastatic lesions of prostate cancer were detected by 18F-sodium fluoride PET/CT imaging at an outside facility. 18F-fluciclovine PET/CT imaging was performed to evaluate local recurrence of prostate cancer at surgical bed of prostatectomy and distant metastasis. One small focus of low-level 18F-fluciclovine radiotracer uptake was noted in the surgical bed of prostatectomy without corresponding soft tissue mass on CT. No fluciclovine-avid lymph nodes or osseous metastatic lesions were detected, but multiple hypodense lesions of variable 18F-fluciclovine radiotracer uptake were noted in the liver, concerning for isolated liver metastasis of prostate cancer. The patient underwent docetaxel chemotherapy for treatment of prostate cancer liver metastasis and showed a favorable response to treatment by significant decreased size of the hypodense lesions in the liver on post treatment abdominal CT, along with dramatic reduction of PSA level and improvement of liver function. The findings from this case highlight the importance of checking hypoattenuating lesions in the liver for the presence of prostate cancer metastatic lesions that might appear similar to other benign hypoattenuating lesions of low fluciclovine uptake relative to physiological 18F-fluciclovine uptake in the normal liver tissues, a potential pitfall at interpretation of 18F-fluociclovine PET/CT imaging.
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OBJECTIVE: To investigate the prognostic value of metabolic tumor volume (MTV) and total lesion glycolysis (TLG), measured by preoperative ¹8F-fluorodeoxyglucose positron emission tomography/computed tomography (¹8F-FDG PET/CT), in risk stratification of patients with endometrial carcinoma (EC). METHODS: The patients with pathological diagnosis of EC who underwent preoperative ¹8F-FDG PET/CT imaging were retrospectively selected for analysis of the prognostic values of PET parameters in risk classification and lymph node metastases (LNMs). Receiver-operating-characteristic analysis was used to analyze the correlation of PET parameters cutoff values with deep myometrial invasion (MI), lymphovascular space involvement and LNM for prognostic values in risk stratification. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for detection of LNM are 83.3%, 99.7%, 90.9%, 99.5% and 99.2%, respectively. The MTV and TLG of primary lesion of EC in the patients with LNM are notably higher than those in patients without LNM, p<0.010. The MTV and TLG of the EC primary lesions in high-risk patients are significantly higher than those in low-risk patients (p<0.010), but the maximum standardized uptake value (SUVmax) is not. The MTV and TLG of primary lesions were superior to SUVmax for predicting of deep MI, LNM and high-risk of EC (p<0.005). CONCLUSION: MTV and TLG of primary lesions are more valuable in predicting risk stratification of EC patients. Preoperative ¹8F-FDG PET/CT imaging is useful in predicting the LNM of EC and may help guide pelvic lymphadenectomy to avoid unnecessary pelvic lymphadenectomy in EC patients with low-risk stratification.
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Neoplasias Endometriales/patología , Fluorodesoxiglucosa F18/metabolismo , Glucólisis , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Medición de Riesgo/métodos , Carga Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/diagnóstico por imagen , Neoplasias Endometriales/metabolismo , Femenino , Humanos , Escisión del Ganglio Linfático/métodos , Metástasis Linfática , Persona de Mediana Edad , Pronóstico , Curva ROC , Radiofármacos/metabolismo , Estudios RetrospectivosRESUMEN
Meta-iodobenzylguanidine (MIBG) is a ligand with high affinity against norepinephrine transporter (NET) that has been used for diagnostic imaging and radionuclide therapy of NET-expressing tumors, such as neuroblastoma. We hypothesize that MIBG can be used as a ligand for development of new anticancer drugs targeting NET-expressing neuroblastoma (NB). To test our hypothesis, we synthesized two MIBG-based anticancer copper complexes [Cu(m-TSBG)2 and Cu(p-TSBG)2] by conjugation of a thiosemicarbazone copper group onto MIBG ligand. Both Cu(m-TSBG)2 and Cu(p-TSBG)2 compounds showed potent anticancer activity against NB cells (BE2C and SK-N-DZ cells). The NB-specific anticancer activity of Cu(m-TSBG)2 and Cu(p-TSBG)2 was further demonstrated by the reduced anticancer activities when nonconjugated MIBG ligand was used to competitively block binding of Cu(m-TSBG)2 or Cu(p-TSBG)2 onto NET-expressing NB cells. Both Cu(m-TSBG)2 or Cu(p-TSBG)2 compounds hold potential as promising new drugs for targeted therapy of neuroblastoma and other NET-expressing tumors.
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3-Yodobencilguanidina/metabolismo , Antineoplásicos/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Neuroblastoma/metabolismo , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/metabolismo , Semicarbacidas/metabolismo , 3-Yodobencilguanidina/química , 3-Yodobencilguanidina/farmacología , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Cobre/química , Cobre/metabolismo , Cobre/farmacología , Guanidinas/química , Guanidinas/metabolismo , Guanidinas/farmacología , Humanos , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/antagonistas & inhibidores , Semicarbacidas/química , Semicarbacidas/farmacologíaAsunto(s)
Adenoma/diagnóstico , Coristoma , Neoplasias Hepáticas/diagnóstico , Tumores Neuroendocrinos/diagnóstico , Enfermedades Pancreáticas/patología , Neoplasias Pancreáticas/diagnóstico , Bazo , Adenoma/patología , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Tumores Neuroendocrinos/patología , Pancreatectomía , Neoplasias Pancreáticas/patologíaRESUMEN
Copper 8-hydroxyquinoline-2-carboxaldehyde-thiosemicarbazide complex (CuHQTS) is a copper complex with strong anticancer activity against cisplatin-resistant neuroblastoma and prostate cancer cells in vitro by cell proliferation assay or fluorescent microscopic imaging. This study aimed to evaluate anti-prostate cancer activity of CuHQTS in vivo by bioluminescence imaging (BLI) and tumor size measurement, using athymic nu/nu mice implanted with prostate cancer cells carrying luciferase reporter gene (Luc-PC3). Growth of Luc-PC3 cells (1 × 105 cells) implanted in athymic nu/nu mice treated with CuHQTS for 2 weeks was suppressed by measurement of luciferase signals (6.18 × 107 to 5.36 × 107 p/s/cm2/sr) with BLI, compared with luciferase signals of Luc-PC3 cells (4.66 × 107 to 1.51 × 108 p/s/cm2/sr, p < 0.05) in the mice treated with normal saline of placebo control. Moreover, the size of PC-3 xenograft tumor (126.5 ± 34.2 mm3) in athymic nu/nu mice treated with CuHQTS was significantly smaller than the size of PC-3 xenograft tumor (218.6 ± 48.0 mm3, p < 0.05) in athymic nu/nu mice treated with normal saline of placebo control, suggesting in vivo tumor growth inhibition activity of CuHQTS on prostate cancer. The findings of this study support further investigation of CuHQTS as a promising new anticancer agent for the treatment of metastatic prostate cancer refractory to anticancer drugs currently available.
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Antineoplásicos/farmacología , Oxiquinolina/química , Semicarbacidas/química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Mediciones Luminiscentes , Masculino , Ratones , Ratones Desnudos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Aim: To synthesize and evaluate the imaging potential of Bom-PEG-[64Cu]CuS nanoparticles (NPs) in orothotopic prostate tumor. Materials & methods: [64Cu]CuS NPs were synthesized in aqueous solution by 64CuCl2 and Na2S reaction. Then PEG linker with or without bombesin peptide were conjugated to the surface of [64Cu]CuS NPs to produce Bom-PEG-[64Cu]CuS and PEG-[64Cu]CuS NPs. These two kinds of NPs were used for testing specific uptake in prostate cancer cells in vitro and imaging of orthotopic prostate tumor in vivo. Results: Bom-PEG-[64Cu]CuS and PEG-[64Cu]CuS NPs were successfully synthesized with core diameter of approximately 5 nm. Radioactive cellular uptake revealed that Bom-PEG-[64Cu]CuS was able to specifically bind to prostate cancer cells, and the microPET-CT imaging indicated clear visualization of orthotopic prostate tumors. Conclusion: Radiolabeled Bom-PEG-[64Cu]CuS NPs have potential as an ideal agent for orthotopic prostate tumor imaging by microPET-CT.
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Brain aging is associated with changes of various metabolic pathways. Copper is required for brain development and function, but little is known about changes in copper metabolism during brain aging. The objective of this study was to investigate alteration of copper fluxes in the aging mouse brain with positron emission tomography/computed tomography using 64CuCl2 as a radiotracer (64CuCl2-PET/CT). A longitudinal study was conducted in C57BL/6 mice (n = 5) to measure age-dependent brain and whole-body changes of 64Cu radioactivity using PET/CT after oral administration of 64CuCl2 as a radiotracer. Cerebral 64Cu uptake at 13 months of age (0.17 ± 0.05 %ID/g) was higher than the cerebral 64Cu uptake at 5 months of age (0.11 ± 0.06 %ID/g, p < 0.001), followed by decrease to (0.14 ± 0.04 %ID/g, p = 0.02) at 26 months of age. In contrast, cerebral 18F-FDG uptake was highest at 5 months of age (7.8 ± 1.2 %ID/g) and decreased to similar values at 12 (5.2 ± 1.1 %ID/g, p < 0.001) and 22 (5.6 ± 1.1 %ID/g, p < 0.001) months of age. The findings demonstrated alteration of copper fluxes associated with brain aging and the time course of brain changes in copper fluxes differed from changes in brain glucose metabolism across time, suggesting independent underlying physiological processes. Hence, age-dependent changes of cerebral copper fluxes might represent a novel metabolic biomarker for assessment of human brain aging process with PET/CT using 64CuCl2 as a radiotracer.
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Copper complexes with strong anticancer activity are promising new drugs for treatment of patients with metastatic cancer. Copper 8-hydroxyquinoline-2-carboxaldehyde-thiosemicarbazide (CuHQTS) and copper 8-hydroxyquinoline-2-carboxaldehyde-4,4-dimethyl-3-thiosemicarbazide (CuHQDMTS) were found to have strong anticancer activity against cisplatin-resistant neuroblastoma cells and prostate cancer cells. This study aimed to synthesize and characterize two new anticancer copper complexes, copper complex of (4R)-(-)-2-Thioxo-4-thiazolidinecarboxylic acid (CuTTDC), and copper complex of 3-Rhodaninepropionic acid-copper complex (CuRDPA). Cell growth inhibition and cytotoxicity of CuTTDC and CuRDPA on prostate and breast cancer cells were evaluated with Cell Counting Kits-8 (CCK8) assay and fluorescent microscopic imaging respectively. Strong anticancer activity of CuTTDC and CuRDPA was demonstrated by growth inhibition and cytotoxicity of prostate and breast cancer cells treated with these two copper complexes, supporting further investigation of potential use of these two new anticancer complexes for treatment of prostate and breast cancer metastasis.
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Antineoplásicos/farmacología , Neoplasias de la Mama/patología , Complejos de Coordinación/farmacología , Cobre/química , Propionatos/química , Neoplasias de la Próstata/patología , Tiazolidinas/química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Complejos de Coordinación/química , Femenino , Humanos , Masculino , Microscopía Fluorescente , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/tratamiento farmacológico , Células Tumorales CultivadasRESUMEN
Background: Brain development and maturation in adolescence is a complex process with active changes of metabolic and neurotransmission pathways. Positron emission tomography (PET) is a useful imaging modality for tracking metabolic and functional changes in adolescent brain. In this study, changes of glucose metabolism, expression of vesicular monoamine transporter 2 and dopamine transporter during adolescent brain development in rats were investigated with PET/CT. Methods: A longitudinal PET/CT study of age-dependent changes of VMAT2, DAT and glucose metabolism in adolescent brain was conducted in a group of Wistar rats (n = 6) post sequential intravenous injection of 18F-PF-(+)-DTBZ, 11C-CFT, and 18F-FDG, respectively. PET acquisition was performed at 2, 4, 9, and 12 months of age. Radiotracer uptake in different brain regions, including the striatum, cerebellum, and hippocampus, were quantified and recorded as Standardized uptake value (SUV) and striatal specific uptake ratio (SUVR: SUV in brain regions/SUV in cerebellum). Results: Variable uptake of 18F-PF-(+)-DTBZ and 11C-CFT were detected, with highest level uptake in the striatum and accumbens. There was significant age-dependent increase of 18F-PF-(+)-DTBZ and 11C-CFT uptake in the striatum from 2 months of age (SUV: 1.36 ± 0.22, 1.37 ± 0.39, respectively), to 4 months (SUV: 2.22 ± 0.29, 2.04 ± 0.33), 9 months (1.98 ± 0.34, 2.09 ± 0.18), 12 months (SUV: 1.93 ± 0.19, 2.00 ± 0.17) of age, SUV of 18F-FDG also increased from 2 months of age to older ages (SUV in the striatum: 3.71 ± 0.78 at 2 month, 5.28 ± 0.81, 5.14 ± 0.73, 4.94 ± 0.50 at 4, 9, 12 month, respectively). Conclusion: Age-dependent increases of striatal of 18F-FDG, 18F-PF-(+)-DTBZ, and 11C-CFT uptake were detected in rats from 2 to 4 month of age, demonstrating striatal development presents over the first 4 months of age. Four months of age can be considered a safe threshold to launch brain disease studies for exclusion of confusion of continuing tissue development. These findings support further investigation of age-dependent changes in expression of DAT, VMAT2, and glucose metabolism for their potential use as a new imaging biomarker for study of brain development and functional maturation.