Artificial intelligence-driven drug repositioning uncovers efavirenz as a modulator of α-synuclein propagation: Implications in Parkinson's disease.

Parkinson's disease (PD) is a complex neurodegenerative disorder with an unclear etiology. Despite significant research efforts, developing disease-modifying treatments for PD remains a major unmet medical need. Notably, drug repositioning is becoming an increasingly attractive direction in drug discovery, and computational approaches offer a relatively quick and resource-saving method for identifying testable hypotheses that promote drug repositioning. We used an artificial intelligence (AI)-based drug repositioning strategy to screen an extensive compound library and identify potential therapeutic agents for PD. Our AI-driven analysis revealed that efavirenz and nevirapine, approved for treating human immunodeficiency virus infection, had distinct profiles, suggesting their potential effects on PD pathophysiology. Among these, efavirenz attenuated α-synuclein (α-syn) propagation and associated neuroinflammation in the brain of preformed α-syn fibrils-injected A53T α-syn Tg mice and α-syn propagation and associated behavioral changes in the C. elegans BiFC model. Through in-depth molecular investigations, we found that efavirenz can modulate cholesterol metabolism and mitigate α-syn propagation, a key pathological feature implicated in PD progression by regulating CYP46A1. This study opens new avenues for further investigation into the mechanisms underlying PD pathology and the exploration of additional drug candidates using advanced computational methodologies.

Integration of National Health Insurance claims data and animal models reveals fexofenadine as a promising repurposed drug for Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is a common and costly progressive neurodegenerative disease of unclear etiology. A disease-modifying approach that can directly stop or slow its progression remains a major unmet need in the treatment of PD. A clinical pharmacology-based drug repositioning strategy is a useful approach for identifying new drugs for PD. METHODS: We analyzed claims data obtained from the National Health Insurance Service (NHIS), which covers a significant portion of the South Korean population, to investigate the association between antihistamines, a class of drugs commonly used to treat allergic symptoms by blocking H1 receptor, and PD in a real-world setting. Additionally, we validated this model using various animal models of PD such as the 6-hydroxydopmaine (6-OHDA), α-synuclein preformed fibrils (PFF) injection, and Caenorhabditis elegans (C. elegans) models. Finally, whole transcriptome data and Ingenuity Pathway Analysis (IPA) were used to elucidate drug mechanism pathways. RESULTS: We identified fexofenadine as the most promising candidate using National Health Insurance claims data in the real world. In several animal models, including the 6-OHDA, PFF injection, and C. elegans models, fexofenadine ameliorated PD-related pathologies. RNA-seq analysis and the subsequent experiments suggested that fexofenadine is effective in PD via inhibition of peripheral immune cell infiltration into the brain. CONCLUSION: Fexofenadine shows promise for the treatment of PD, identified through clinical data and validated in diverse animal models. This combined clinical and preclinical approach offers valuable insights for developing novel PD therapeutics.

Critical roles of parkin and PINK1 in coxsackievirus B3-induced viral myocarditis.

Viral myocarditis is an inflammatory disease of the myocardium, often leads to cardiac dysfunction and death. PARKIN (PRKN) and PINK1, well known as Parkinson's disease-associated genes, have been reported to be involved in innate immunity and mitochondrial damage control. Therefore, we investigated the role of parkin and PINK1 in coxsackievirus B3 (CVB3)-induced viral myocarditis because the etiology of myocarditis is related to abnormal immune response to viral infection and mitochondrial damage. After viral infection, the survival was significantly lower and myocardial damage was more severe in parkin knockout (KO) and PINK1 KO mice compared to wild-type (WT) mice. Parkin KO and PINK1 KO showed defective immune cell recruitment and impaired production of antiviral cytokines such as interferon-gamma, allowing increased viral replication. In addition, parkin KO and PINK1 KO mice were more susceptible to CVB3-induced mitochondrial damage than WT mice, resulting in susceptibility to viral-induced cardiac damage. Finally, using publicly available RNA-seq data, we found that pathogenic mutants of the PRKN gene are more common in patients with dilated cardiomyopathy and myocarditis than in controls or the general population. This study will help elucidate the molecular mechanism of CVB3-induced viral myocarditis.

Neuronal ApoE Regulates the Cell-to-Cell Transmission of α-Synuclein.

The presence of protein inclusions, called Lewy bodies (LBs) and Lewy neurites (LNs), in the brain is the main feature of Parkinson's disease (PD). Recent evidence that the prion-like propagation of α-synuclein (α-syn), as a major component of LBs and LNs, plays an important role in the progression of PD has gained much attention, although the molecular mechanism remains unclear. In this study, we evaluated whether neuronal ApoE regulates the cell-to-cell transmission of α-syn and explored its molecular mechanism using in vitro and in vivo model systems. We demonstrate that neuronal ApoE deficiency attenuates both α-syn uptake and release by downregulating LRP-1 and LDLR expression and enhancing chaperone-mediated autophagy activity, respectively, thereby contributing to α-syn propagation. In addition, we observed that α-syn propagation was attenuated in ApoE knockout mice injected with pre-formed mouse α-syn fibrils. This study will help our understanding of the molecular mechanisms underlying α-syn propagation.

Age-related increase in caveolin-1 expression facilitates cell-to-cell transmission of α-synuclein in neurons.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease, with aging being considered the greatest risk factor for developing PD. Caveolin-1 (Cav-1) is known to participate in the aging process. Recent evidence indicates that prion-like propagation of misfolded α-synuclein (α-syn) released from neurons to neighboring neurons plays an important role in PD progression. In the present study, we demonstrated that cav-1 expression in the brain increased with age, and considerably increased in the brain of A53T α-syn transgenic mice. Cav-1 overexpression facilitated the uptake of α-syn into neurons and formation of additional Lewy body-like inclusion bodies, phosphorylation of cav-1 at tyrosine 14 was found to be crucial for this process. This study demonstrates the relationship between age and α-syn spread and will facilitate our understanding of the molecular mechanism of the cell-to-cell transmission of α-syn.

The dual role of c-src in cell-to-cell transmission of α-synuclein.

Parkinson's disease (PD) is characterized by the loss of dopaminergic neurons located in the substantia nigra pars compacta and the presence of proteinaceous inclusions called Lewy bodies and Lewy neurites in numerous brain regions. Increasing evidence indicates that Lewy pathology progressively involves additional regions of the nervous system as the disease advances, and the prion-like propagation of α-synuclein (α-syn) pathology promotes PD progression. Accordingly, the modulation of α-syn transmission may be important for the development of disease-modifying therapies in patients with PD. Here, we demonstrate that α-syn fibrils induce c-src activation in neurons, which depends on the FcγRIIb-SHP-1/-2-c-src pathway and enhances signals for the uptake of α-syn into neurons. Blockade of c-src activation inhibits the uptake of α-syn and the formation of Lewy body-like inclusions. Furthermore, the blockade of c-src activation also inhibits the release of α-syn via activation of autophagy. The brain-permeable c-src inhibitor, saracatinib, efficiently reduces α-syn propagation into neighboring regions in an in vivo model system. These results suggest a new therapeutic target against progressive PD.

Utility of Two Surgical Techniques Using a Lateral Intercostal Artery Perforator Flap after Breast-Conserving Surgery: A Single-Center Retrospective Study.

BACKGROUND: Immediate partial breast reconstruction after breast-conserving surgery has become a new paradigm in treating breast cancer. Among the volume replacement techniques used for small to moderate-sized breasts, the perforator flap method has many advantages. The authors present anatomical studies and two surgical techniques using lateral intercostal artery perforator flaps. METHODS: Data from 40 patients who underwent breast reconstruction using the lateral intercostal artery perforator flap between January of 2011 and June of 2016 were included. The authors conducted comparative analyses of the propeller flap and the turnover flap. They used three-dimensional computed tomography in lateral intercostal artery perforator flap anatomical studies, analyzing the distribution probability of the dominant perforator, the vertical distance from the axillary fold, and the horizontal distance from the anterior border of the latissimus dorsi. RESULTS: The most dominant perforator used for lateral intercostal artery perforator flaps was the sixth lateral intercostal artery perforator (43.6 percent of cases), followed by the seventh lateral intercostal artery perforator (39.1 percent of cases); their mean distances from the latissimus dorsi and the axillary folds were determined and reported. Complications included three cases requiring additional treatment for fat necrosis (propeller method, two cases; turnover method, one case) and venous congestion in only two cases that used the propeller method. Cosmetic satisfaction was 90 percent or greater for both techniques, indicating that results were rated as either excellent or good. CONCLUSION: The authors believe that their study results can broaden the application of partial breast reconstruction by using the lateral intercostal artery perforator flap after breast-conserving surgery, with three-dimensional computed tomography for anatomical studies, and using one of the authors' two described surgical techniques. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Effects of Stromal Vascular Fraction on Breast Cancer Growth and Fat Engraftment in NOD/SCID Mice.

BACKGROUND: To overcome unpredictable fat graft resorption, cell-assisted lipotransfer using stromal vascular fraction (SVF) has been introduced. However, its effect on cancer growth stimulation and its oncological safety are debatable. We investigated the effect of SVF on adjacent breast cancer and transplanted fat in a mouse model. METHODS: A breast cancer xenograft model was constructed by injecting 2 × 106 MDA-MB-231-luc breast cancer cells into the right lower back of 40 NOD/SCID mice. Two weeks later, cancer size was sorted according to signal density using an in vivo optical imaging system, and 36 mice were included. Human fat was extracted from the abdomen, and SVFs were isolated using a component isolator. The mice were divided into four groups: A, controls; B, injected with 30 µl SVF; C, injected with 0.5 ml fat and 30 µl saline; group D, injected with 0.5 ml fat and 30 µl SVF. Magnetic resonance imaging and three-dimensional micro-computed tomography volumetric analysis were performed at 4 and 8 weeks. RESULTS: Tumor volume was 43.6, 42.3, 48.7, and 42.4 mm3 at the initial time point and 6780, 5940, 6080, and 5570 mm3 at 8 weeks in groups A, B, C, and D, respectively. Fat graft survival volume after 8 weeks was 49.32% and 62.03% in groups C and D, respectively. At 2-month follow-up after fat grafting in the xenograft model, SVF injection showed an increased fat survival rate and did not increase the adjacent tumor growth significantly. CONCLUSION: Fat grafting with SVF yields satisfactory outcome in patients who undergo breast reconstruction surgery. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A murine model of radiation-induced capsule-tissue reactions around smooth silicone implants.

As the availability of breast reconstruction using implants is becoming widespread and many implant recipients undergo radiation therapy, there is an increasing interest in understanding the potential complications associated with capsule-tissue interactions in response to irradiation. Accordingly, our medical institution designed an animal experiment to investigate the effects of irradiation on capsular contracture. A total of 40 mice (C57BL6) were divided into four groups according to whether or not they received irradiation and the time from implantation to irradiation. After each mouse received a specially-fabricated, 1.5 cm semi-spherical silicone implant inserted into the area below the panniculus carnosus, half of the mice were irradiated using singe administration of a 10 Gy dose of radiation (6 MeV). Subsequently, data from gross inspection, histological analysis and immunohistochemical analysis were obtained at one and three months postoperatively and analyzed. Changes that occurred near the capsule led to the phenomenon of contracture subsequent to encapsulation. Our findings suggest that the inflammation reaction occurring near the implant becomes aggravated by 'radiation toxicity' and creates an environment conducive to capsular contracture. The present study demonstrated the process by which the complication of capsular contracture may occur during the treatment of human breast cancer via radiotherapy. These findings may serve as the basis for research and development of future treatments of capsular contracture.

Prion-like Propagation of α-Synuclein Is Regulated by the FcγRIIB-SHP-1/2 Signaling Pathway in Neurons.

Recent evidence of prion-like propagation of α-synuclein (α-syn) into neighboring neurons set up a paradigm to elucidate the mechanism of progression of Parkinson's disease (PD) and to develop therapeutic strategies. Here, we show that FcγRIIB expressed in neurons functions as a receptor for α-syn fibrils and mediates cell-to-cell transmission of α-syn. SHP-1 and 2 are activated downstream by α-syn fibrils through FcγRIIB and play an important role in cell-to-cell transmission of α-syn. Also, taking advantage of a co-culture system, we show that cell-to-cell transmission of α-syn induces intracellular Lewy body-like inclusion body formation and that the FcγRIIB/SHP-1/2 signaling pathway is involved in it. Therefore, the FcγRIIB-SHP-1/-2 signaling pathway may be a therapeutic target for the progression of PD. The in vitro system is an efficient tool for further high-throughput screening that can be used for developing a therapeutic intervention in PD.

The usefulness of pedicled perforator flap in partial breast reconstruction after breast conserving surgery in Korean women.

BACKGROUND: The emergence of breast-conserving surgery combined with radiotherapy as the treatment of choice for early stage breast cancer has resulted in greater focus on oncoplastic breast surgery. The use of perforator flaps has particularly gained in reputation for its effectiveness in the reconstruction of partial breast defects in Korean women. Herein, we present our experience with the use of thoracodorsal artery perforator (TDAP) and lateral intercostal artery perforator (LICAP) flaps. METHODS: This study included 33 patients who underwent breast reconstruction using TDAP or LICAP flaps at our hospital from January 2011 to December 2014. Data from patient medical records, and patient satisfaction surveys, which were conducted 12 months postoperatively, were retrospectively evaluated. RESULTS: TDAP and LICAP flap-based reconstructions were performed in 14 and 19 patients, respectively. Five patients developed complications that required additional intervention. Overall patient satisfaction was observed to be excellent in 15 (46%) patients, and good in 12 (36%). CONCLUSIONS: Based on our experience, oncoplastic breast surgery using TDAP or LICAP flap is an effective remodeling technique for small-to-moderate breast defects in Korean women with smaller breasts.

Clinical Characteristics of Arteriovenous Malformations of the Head and Neck.

BACKGROUND: Arteriovenous malformation (AVM) of the head and neck regions show low incidence; hence, studies regarding the causative factors of onset, diagnostic criteria, clinical aspects, treatment methods, and outcomes remain lacking. OBJECTIVE: To share the diagnostic and treatment experiences at the center and to understand the treatments' effect through a retrospective analysis of cases in the past 15 years. MATERIALS AND METHODS: The authors included 60 patients with AVM in the head and neck area between January 1999 and September 2014 to investigate diagnostic methods, distributions and locations of lesions, clinical stage, and treatment methods by retrospective evaluation. RESULTS: In all, 3.7% were diagnosed with AVMs of the head and neck. No sex-related differences were observed, and the mean age at diagnosis was 27.6 ± 14.24 years. The left (26 patients, 43%) and V2 sections (33 patients, 55%) of the head and neck were the most frequent locations. Stage II (28 patients, 47%) had the largest distribution. Forty-four patients (73%) showed improvement after sclerotherapy, embolization, and surgical resection. CONCLUSION: The diagnosis and treatment of AVMs should be approached on a case-by-case basis by gathering opinions from specialists in each department using medical history, physical examination, and imaging results.

Cervicofacial Lymphatic Malformations: A Retrospective Review of 40 Cases.

BACKGROUND: Lymphatic malformation (LM) is a form of congenital vascular malformation with a low incidence. Although LM has been studied, no consensus has emerged regarding its cause or treatment. METHODS: In this study, we retrospectively evaluated 40 patients who visited our vascular anomalies center for the treatment of cervicofacial LM, which is a common manifestation of LM. The medical records of patients over a period of 12 years were reviewed and analyzed for commonalities regarding the diagnosis and the results of treatment. RESULTS: Suspected cervicofacial LM was confirmed through imaging studies. No difference in incidence was observed according to sex, and 73% of patients first presented with symptoms before the age of two years. The left side and the V2-V3 area were most commonly affected. No significant differences in incidence were observed among the macrocystic, microcystic, and combined types of LM. A total of 28 out of 36 patients received sclerotherapy as the first choice of treatment, regardless of the type of lesion. Complete resolution was achieved in only 25% of patients. CONCLUSIONS: LM is important to confirm the diagnosis early and to choose an appropriate treatment strategy according to the stage of the disease and each individual patient's symptoms. When treatment is delayed or an incorrect treatment is administered, patient discomfort increases as the lesion gradually spreads. Therefore, more so than is the case for most other diseases, a team approach on a case-by-case basis is important for the accurate and appropriate treatment of LM.

Factors prognostic for phonetic development after cleft palate repair.

BACKGROUND: Palatoplasty is aimed to achieve normal speech, improve food intake, and ensure successful maxillary growth. However, the velopharyngeal function is harder to control than other functions. Therefore, many studies on the prognostic factor of velopharyngeal insufficiency have been conducted. This study aimed to evaluate the relationships between speech outcomes and multimodality based on intraoral and preoperative three-dimensional computerized tomographic (CT) findings. METHODS: Among 73 children with cleft palate who underwent palatoplasty between April 2011 and August 2014 at Kyungpook National University Hospital (KNUH), 27 were retrospectively evaluated. The 27 cases were non-syndromic, for which successful speech evaluation was conducted by a single speech-language pathologist (Table 1). Successful speech evaluation was defined as performing the test three times in 6-month intervals. Three intraoral parameters were measured before and immediately after operation (Fig. 1). On axial- and coronal-view preoperative facial CT, 5 and 2 different parameters were analyzed, respectively (Figs. 2 and 3). Regression analysis (SPSS IBM 22.0) was used in the statistical analysis. RESULTS: Two-flap palatoplasty and Furlow's double opposing Z-plasty were performed in 15 and 12 patients, respectively. The operation was performed 11 months after birth on average. Children with a higher palatal arch and wider maxillary tuberosity distance showed hypernasality (p < 0.05; Table 2). CONCLUSIONS: The useful prognostic factors of velopharyngeal function after palatoplasty were palate width and height, rather than initial diagnosis, treatment method, or palate length. Therefore, a more active intervention is needed, such as orthopedic appliance, posterior pharyngeal wall augmentation, or early speech training.

p190RhoGAP and Rap-dependent RhoGAP (ARAP3) inactivate RhoA in response to nerve growth factor leading to neurite outgrowth from PC12 cells.

Rat pheochromocytoma (PC12) cells have been used to investigate neurite outgrowth. Nerve growth factor (NGF) has been well known to induce neurite outgrowth from PC12 cells. RhoA belongs to Ras-related small GTP-binding proteins, which regulate a variety of cellular processes, including cell morphology alteration, actin dynamics, and cell migration. NGF suppressed GTP-RhoA levels after 12 h in PC12 cells and was consistently required for a long time to induce neurite outgrowth. Constitutively active (CA)-RhoA suppressed neurite outgrowth from PC12 cells in response to NGF, whereas dominant-negative (DN)-RhoA stimulated it, suggesting that RhoA inactivation is essential for neurite outgrowth. Here, we investigated the mechanism of RhoA inactivation. DN-p190RhoGAP abrogated neurite outgrowth, whereas wild-type (WT)-p190RhoGAP and WT-Src synergistically stimulated it along with accelerating RhoA inactivation, suggesting that p190RhoGAP, which can be activated by Src, is a major component in inhibiting RhoA in response to NGF in PC12 cells. Contrary to RhoA, Rap1 was activated by NGF, and DN-Rap1 suppressed neurite outgrowth, suggesting that Rap1 is also essential for neurite outgrowth. RhoA was co-immunoprecipitated with Rap1, suggesting that Rap1 interacts with RhoA. Furthermore, a DN-Rap-dependent RhoGAP (ARAP3) prevented RhoA inactivation, abolishing neurite formation from PC12 cells in response to NGF. These results suggest that NGF activates Rap1, which, in turn, up-regulates ARAP3 leading to RhoA inactivation and neurite outgrowth from PC12 cells. Taken together, p190RhoGAP and ARAP3 seem to be two main factors inhibiting RhoA activity during neurite outgrowth in PC12 cells in response to NGF.

Hedgehog signaling regulates proliferation of prostate cancer cells via stathmin1.

Hedgehog (Hh) signaling is an essential pathway in embryonic development of prostate. Hh also plays roles in the proliferation of progenitor cells and cancer cells of adult prostate. However, how Hh signaling contributes to carcinogenesis of prostate is poorly understood. Stathmin1 is a microtubule-regulating protein that plays an important role in the assembly and disassembly of the mitotic spindle. Stathmin1 is expressed in normal developing mouse prostate and in prostate cancer. The expression pattern of stathmin1 is similar to that of Shh in prostate development and cancer, suggesting a connection between these two proteins. In this study, we examined the relationship between stathmin1 and Hh signaling. Here, we show that stathmin1 expression is regulated by Hh signaling in prostate cancer cells. Cyclopamine, a specific inhibitor of Hh signaling, reduced the expression of stathmin1 in prostate cancer cells. However, the Shh peptide induced stathmin1 expression. Overexpression of Gli1 further confirmed the relationship. Co-expression of stathmin1 and Patched 1, a receptor for Hh signaling was observed in prostate cancer tissues. Cyclopamine and stathmin1 siRNA both decreased proliferation of prostate cancer cells but did not produce an additive effect, suggesting a common pathway. These results suggest that Hh signaling regulates proliferation of prostate cancer cells by controlling stathmin1 expression.

Regulation of cerebrospinal fluid production by caffeine consumption.

BACKGROUND: Caffeine is the most commonly consumed psycho-stimulant in the world. The effects of caffeine on the body have been extensively studied; however, its effect on the structure of the brain has not been investigated to date. RESULTS: In the present study we found that the long-term consumption of caffeine can induce ventriculomegaly; this was observed in 40% of the study rats. In the caffeine-treated rats with ventriculomegaly, there was increased production of CSF, associated with the increased expression of Na(+), K(+)-ATPase and increased cerebral blood flow (CBF). In contrast to the chronic effects, acute treatment with caffeine decreased the production of CSF, suggesting 'effect inversion' associated with caffeine, which was mediated by increased expression of the A1 adenosine receptor, in the choroid plexus of rats chronically treated with caffeine. The involvement of the A1 adenosine receptor in the effect inversion of caffeine was further supported by the induction of ventriculomegaly and Na+, K+-ATPase, in A1 agonist-treated rats. CONCLUSION: The results of this study show that long-term consumption of caffeine can induce ventriculomegaly, which is mediated in part by increased production of CSF. Moreover, we also showed that adenosine receptor signaling can regulate the production of CSF by controlling the expression of Na(+), K(+)-ATPase and CBF.

Hedgehog signaling regulates the survival of gastric cancer cells by regulating the expression of Bcl-2.

Gastric cancer is the second most common cause of cancer deaths worldwide. The underlying molecular mechanisms of its carcinogenesis are relatively poorly characterized. Hedgehog (Hh) signaling, which is critical for development of various organs including the gastrointestinal tract, has been associated with gastric cancer. The present study was undertaken to reveal the underlying mechanism by which Hh signaling controls gastric cancer cell proliferation. Treatment of gastric cancer cells with cyclopamine, a specific inhibitor of Hh signaling pathway, reduced proliferation and induced apoptosis of gastric cancer cells. Cyclopamine treatment induced cytochrome c release from mitochondria and cleavage of caspase 9. Moreover, Bcl-2 expression was significantly reduced by cyclopamine treatment. These results suggest that Hh signaling regulates the survival of gastric cancer cells by regulating the expression of Bcl-2.