RESUMEN

Mild cognitive impairment (MCI) is a prodromal stage of Alzheimer's disease (AD) that causes a significant burden in caregiving and medical costs. Clinically, the diagnosis of MCI is determined by the impairment statuses of five cognitive domains. If one of these cognitive domains is impaired, the patient is diagnosed with MCI, and if two out of the five domains are impaired, the patient is diagnosed with AD. In medical records, most of the time, the diagnosis of MCI/AD is given, but not the statuses of the five domains. We may treat the domain statuses as missing variables. This diagnostic procedure relates MCI/AD status modeling to multiple-instance learning, where each domain resembles an instance. However, traditional multiple-instance learning assumes common predictors among instances, but in our case, each domain is associated with different predictors. In this article, we generalized the multiple-instance logistic regression to accommodate the heterogeneity in predictors among different instances. The proposed model is dubbed heterogeneous-instance logistic regression and is estimated via the expectation-maximization algorithm because of the presence of the missing variables. We also derived two variants of the proposed model for the MCI and AD diagnoses. The proposed model is validated in terms of its estimation accuracy, latent status prediction, and robustness via extensive simulation studies. Finally, we analyzed the National Alzheimer's Coordinating Center-Uniform Data Set using the proposed model and demonstrated its potential.

RESUMEN

Background: Alzheimer's disease (AD) is a multifactorial disorder characterized by cognitive decline. Current available therapeutics for AD have limited clinical benefit. Therefore, preventive therapies for interrupting the development of AD are critically needed. Molecules targeting multifunction to interact with various pathlogical components have been considered to improve the therapeutic efficiency of AD. In particular, herbal medicines with multiplicity of actions produce cognitive benefits on AD. Bugu-M is a multi-herbal extract composed of Ganoderma lucidum (Antler form), Nelumbo nucifera Gaertn., Ziziphus jujuba Mill., and Dimocarpus longan, with the ability of its various components to confer resilience to cognitive deficits. Objective: To evaluate the potential of Bugu-M on amyloid-ß (Aß) toxicity and its in vitro mechanisms and on in vivo cognitive function. Methods: We illustrated the effect of Bugu-M on Aß25-35-evoked toxicity as well as its possible mechanisms to diminish the pathogenesis of AD in rat cortical neurons. For cognitive function studies, 2-month-old female 3×Tg-AD mice were administered 400 mg/kg Bugu-M for 30 days. Behavioral tests were performed to assess the efficacy of Bugu-M on cognitive impairment. Results: In primary cortical neuronal cultures, Bugu-M mitigated Aß-evoked toxicity by reducing cytoskeletal aberrations and axonal disruption, restoring presynaptic and postsynaptic protein expression, suppressing mitochondrial damage and apoptotic signaling, and reserving neurogenic and neurotrophic factors. Importantly, 30-day administration of Bugu-M effectively prevented development of cognitive impairment in 3-month-old female 3×Tg-AD mice. Conclusion: Bugu-M might be beneficial in delaying the progression of AD, and thus warrants consideration for its preventive potential for AD.

RESUMEN

Cisplatin chemotherapy causes myelosuppression and often limits treatment duration and dose escalation in patients. Novel approaches to circumvent or lessen myelotoxicity may improve clinical outcome and quality of life in these patients. Chlorella sorokiniana (CS) is a freshwater unicellular green alga and exhibits encouraging efficacy in immunomodulation and anticancer in preclinical studies. However, the efficacy of CS on chemoprotection remains unclear. We report here, for the first time, that CS extract (CSE) could protect normal myeloid cells and PBMCs from cisplatin toxicity. Also, cisplatin-induced apoptosis in HL-60 cells was rescued through reservation of mitochondrial function, inhibition of cytochrome c release to cytosol, and suppression of caspase and PARP activation. Intriguingly, cotreatment of CSE attenuated cisplatin-evoked hypocellularity of bone marrow in mice. Furthermore, we observed the enhancement of CSF-GM activity in bone marrow and spleen in mice administered CSE and cisplatin, along with increased CD11b levels in spleen. In conclusion, we uncovered a novel mechanism of CSE on myeloprotection, whereby potentially supports the use of CSE as a chemoprotector against cisplatin-induced bone marrow toxicity. Further clinical investigation of CSE in combination with cisplatin is warranted.

Asunto(s)

Antineoplásicos/efectos adversos , Células de la Médula Ósea/efectos de los fármacos , Cisplatino/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/tratamiento farmacológico , Mitocondrias/metabolismo , Células Mieloides/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Células de la Médula Ósea/patología , Antígeno CD11b/metabolismo , Chlorella , Cisplatino/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Células HL-60 , Humanos , Inmunomodulación , Terapia de Inmunosupresión , Células Mieloides/patología

RESUMEN

Neuroinflammation plays a central role in the pathophysiology of Alzheimer's disease (AD). Compounds that suppress neuroinflammation have been identified as potential therapeutic targets for AD. Rhinacanthin C (RC), a naphthoquinone ester found in Rhinacanthus nasutus Kurz (Acanthaceae), is currently proposed as an effective molecule against inflammation. However, the exact role of RC on neuroinflammation remains to be elucidated. In the present study, we investigated RC effect on modulating lipopolysaccharides (LPS), amyloid-ß peptide (Aß), or interferon-γ- (IFN-γ-) evoked pathological events in neurons and glia. Our findings demonstrated that RC prevented Aß-induced toxicity in rat hippocampal neurons and attenuated LPS-activated nitric oxide (NO) production, inducible nitric oxide synthase (iNOS) expression, and NF-κB signaling in rat glia. Likewise, RC suppressed LPS-induced neuroinflammation by reducing NO production and iNOS, IL-1ß, CCL-2, and CCL-5 mRNA levels in rat microglia. Further studies using BV-2 microglia revealed that RC inhibited LPS-, Aß-, and IFN-γ-stimulated IL-6 and TNF-α secretion. Of note, NF-κB and ERK activation was abrogated by RC in BV-2 cell response to Aß or IFN-γ. Moreover, RC protected neurons from Aß-stimulated microglial conditioned media-dependent toxicity. Collectively, these data highlight the beneficial effects of RC on neuroprotection and support the therapeutic implications of RC to neuroinflammation-mediated conditions.

Asunto(s)

Péptidos beta-Amiloides/metabolismo , Inflamación/tratamiento farmacológico , Lipopolisacáridos/metabolismo , Naftoquinonas/uso terapéutico , Neuronas/metabolismo , Animales , Interferón gamma/metabolismo , Ratones , Naftoquinonas/farmacología , Neuroglía/metabolismo , Ratas , Ratas Sprague-Dawley

RESUMEN

Antrodia cinnamomea (A. cinnamomea) is a Chinese medicinal herb that possesses a broad range of bioactivities, including anti-inflammation. Given that the proinflammatory cytokine IL-17 plays a critical role in the pathogenesis of autoimmune diseases, we investigated whether A. cinnamomea could inhibit the development of Th17 cells, the main producer of IL-17, and exhibit therapeutic effects on an animal model of psoriasis. We found that A. cinnamomea extract (AC) inhibited the differentiation of Th17 cells as well as the production of IL-17A, IL-21, and IL-22 from these cells. This effect was associated with the inhibition of STAT3 phosphorylation and RORγt expression. Notably, the oral administration of AC reduced psoriasis-like inflammation in imiquimod-mediated dermal damage, repressed the expression of IL-17A, IL-22, and TNF-α in skin lesions, and decreased the infiltration of CD4⁺ T cells, CD8⁺ T cells, and neutrophils into the dermis. Finally, serum levels of IL-17A were decreased in AC-treated mice with psoriasis-like skin inflammation. Taken together, these findings indicate that AC inhibits Th17 cell differentiation, suggesting a role for A. cinnamomea in the treatment of psoriasis and other Th17 cell-mediated inflammatory diseases.

Asunto(s)

Antrodia/química , Diferenciación Celular/efectos de los fármacos , Fitoterapia , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Células Th17/efectos de los fármacos , Administración Oral , Aminoquinolinas/farmacología , Animales , Antiinflamatorios/farmacología , Autoinmunidad , Células Cultivadas , Depresión Química , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Imiquimod , Interleucina-17/inmunología , Interleucina-17/metabolismo , Masculino , Ratones Endogámicos C57BL , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Fosforilación/efectos de los fármacos , Psoriasis/inmunología , Psoriasis/metabolismo , Factor de Transcripción STAT3/metabolismo , Piel/inmunología , Piel/metabolismo , Células Th17/metabolismo

RESUMEN

The glial fibrillary acidic protein (GFAP) gene is alternatively spliced to give GFAP-alpha, the most abundant isoform, and seven other differentially expressed transcripts including GFAP-delta. GFAP-delta has an altered C-terminal domain that renders it incapable of self-assembly in vitro. When titrated with GFAP-alpha, assembly was restored providing GFAP-delta levels were kept low (approximately 10%). In a range of immortalized and transformed astrocyte derived cell lines and human spinal cord, we show that GFAP-delta is naturally part of the endogenous intermediate filaments, although levels were low (approximately 10%). This suggests that GFAP filaments can naturally accommodate a small proportion of assembly-compromised partners. Indeed, two other assembly-compromised GFAP constructs, namely enhanced green fluorescent protein (eGFP)-tagged GFAP and the Alexander disease-causing GFAP mutant, R416W GFAP both showed similar in vitro assembly characteristics to GFAP-delta and could also be incorporated into endogenous filament networks in transfected cells, providing expression levels were kept low. Another common feature was the increased association of alphaB-crystallin with the intermediate filament fraction of transfected cells. These studies suggest that the major physiological role of the assembly-compromised GFAP-delta splice variant is as a modulator of the GFAP filament surface, effecting changes in both protein- and filament-filament associations as well as Jnk phosphorylation.

Asunto(s)

Enfermedad de Alexander/genética , Proteína Ácida Fibrilar de la Glía/química , Cadena B de alfa-Cristalina/química , Enfermedad de Alexander/metabolismo , Astrocitos/metabolismo , Línea Celular , Línea Celular Tumoral , Humanos , MAP Quinasa Quinasa 4/metabolismo , Modelos Biológicos , Mutación , Fosforilación , Unión Proteica , Isoformas de Proteínas , Médula Espinal/metabolismo , Transfección

RESUMEN

Here, we describe the early events in the disease pathogenesis of Alexander disease. This is a rare and usually fatal neurodegenerative disorder whose pathological hallmark is the abundance of protein aggregates in astrocytes. These aggregates, termed "Rosenthal fibers," contain the protein chaperones alpha B-crystallin and HSP27 as well as glial fibrillary acidic protein (GFAP), an intermediate filament (IF) protein found almost exclusively in astrocytes. Heterozygous, missense GFAP mutations that usually arise spontaneously during spermatogenesis have recently been found in the majority of patients with Alexander disease. In this study, we show that one of the more frequently observed mutations, R416W, significantly perturbs in vitro filament assembly. The filamentous structures formed resemble assembly intermediates but aggregate more strongly. Consistent with the heterozygosity of the mutation, this effect is dominant over wild-type GFAP in coassembly experiments. Transient transfection studies demonstrate that R416W GFAP induces the formation of GFAP-containing cytoplasmic aggregates in a wide range of different cell types, including astrocytes. The aggregates have several important features in common with Rosenthal fibers, including the association of alpha B-crystallin and HSP27. This association occurs simultaneously with the formation of protein aggregates containing R416W GFAP and is also specific, since HSP70 does not partition with them. Monoclonal antibodies specific for R416W GFAP reveal, for the first time for any IF-based disease, the presence of the mutant protein in the characteristic histopathological feature of the disease, namely Rosenthal fibers. Collectively, these data confirm that the effects of the R416W GFAP are dominant, changing the assembly process in a way that encourages aberrant filament-filament interactions that then lead to protein aggregation and chaperone sequestration as early events in Alexander disease.

Asunto(s)

Enfermedad de Alexander/genética , Enfermedad de Alexander/metabolismo , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Neoplasias/metabolismo , Transducción de Señal/genética , Cadena B de alfa-Cristalina/metabolismo , Enfermedad de Alexander/patología , Sustitución de Aminoácidos/genética , Animales , Arginina/genética , Línea Celular Tumoral , Genes Dominantes , Proteína Ácida Fibrilar de la Glía/deficiencia , Proteínas de Choque Térmico HSP27 , Humanos , Ratones , Chaperonas Moleculares , Mutación Missense , Triptófano/genética

RESUMEN

The R120G mutation in alphaB-crystallin causes desmin-related myopathy. There have been a number of mechanisms proposed to explain the disease process, from altered protein processing to loss of chaperone function. Here, we show that the mutation alters the in vitro binding characteristics of alphaB-crystallin for desmin filaments. The apparent dissociation constant of R120G alphaB-crystallin was decreased while the binding capacity was increased significantly and as a result, desmin filaments aggregated. These data suggest that the characteristic desmin aggregates seen as part of the disease histopathology can be caused by a direct, but altered interaction of R120G alphaB-crystallin with desmin filaments. Transfection studies show that desmin networks in different cell backgrounds are not equally affected. Desmin networks are most vulnerable when they are being made de novo and not when they are already established. Our data also clearly demonstrate the beneficial role of wild-type alphaB-crystallin in the formation of desmin filament networks. Collectively, our data suggest that R120G alphaB-crystallin directly promotes desmin filament aggregation, although this gain of a function can be repressed by some cell situations. Such circumstances in muscle could explain the late onset characteristic of the myopathies caused by mutations in alphaB-crystallin.

Asunto(s)

Desmina/metabolismo , Mutación Puntual/genética , Cadena B de alfa-Cristalina/genética , Cadena B de alfa-Cristalina/metabolismo , Línea Celular , Demecolcina/farmacología , Desmina/ultraestructura , Humanos , Filamentos Intermedios/metabolismo , Filamentos Intermedios/ultraestructura , Enfermedades Musculares/genética , Unión Proteica , Transfección , Vimentina/metabolismo , Cadena B de alfa-Cristalina/ultraestructura