Stimulation of PGC-1α to attenuate Duchenne muscular dystrophy disease pathology and activate autophagy

Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by the absence of functional dystrophin protein. Dystrophin-deficiency results in numerous cellular dysfunctions and increased muscle injury leading to progressive muscle weakness and ultimately death due to cardiomyopathy or respiratory insufficiency. Overexpression of the transcriptional coactivator, PGC-1α, has been shown to provide therapeutic benefits for dystrophic muscle. In a preliminary experiment, quercetin, a nutraceutical that can drive PGC-1α through SIRT1, protected dystrophin-deficient skeletal muscle following 6 months of treatment. Therapies for DMD must demonstrate long-term efficacy, therefore in the first research chapter we evaluated the effect of 12 months of quercetin treatment on dystrophin-deficient skeletal muscle. To improve the lasting efficacy of quercetin, in the second and third research chapters we fed dystrophic mice quercetin in combination with several agents intended to potentiate or augment the effects of quercetin. We found that these quercetin-based cocktails failed to protect muscle from injury or preserve respiratory or muscle function. Collectively, these studies suggest that quercetin and these quercetin-based cocktails do not attenuate disease pathology long-term. Stemming from our biochemical experiments from the first research chapter, we began to investigate the role of autophagy in dystrophic muscle. During autophagy a membrane is formed around protein aggregates or dysfunctional organelles, which then fuses with a lysosome for degradation. To better understand autophagy in the context of DMD and identify new therapeutic targets, in the fourth research chapter we evaluated autophagy at 7 weeks and 17 months of age in healthy and dystrophic mice. We discovered that autophagy was impaired in dystrophic muscle. Additionally, we discovered that lysosome abundance was decreased with advanced disease and Transcription Factor EB (TFEB), a transcription factor that drives lysosome biogenesis, was partially excluded from dystrophic myonuclei. In the fifth research chapter we used an adeno-associated virus (AAV) vector to drive PGC-1α expression, which is known to increase TFEB protein abundance in healthy tissue. The data suggest that PGC-1α overexpression increased TFEB nuclear localization and subsequently lysosome abundance and autophagosome degradation

Attention Shaping: a Reward-Based Learning Method to Enhance Skills Training Outcomes in Schizophrenia

Disturbances in sustained attention commonly interfere with the ability of persons with schizophrenia to benefit from evidence-based psychosocial treatments. Cognitive remediation interventions have thus far demonstrated minimal effects on attention, as have medications. There is thus a gap between the existence of effective psychosocial treatments and patients’ ability to effectively engage in and benefit from them. We report on the results of a multisite study of attention shaping (AS), a behavioral intervention for improving attentiveness and learning of social skills among highly distractible schizophrenia patients. Patients with chronic schizophrenia who were refractory to skills training were assigned to receive either the UCLA Basic Conversation Skills Module (BCSM) augmented with AS (n = 47) or in the standard format (n = 35). AS, a reward-based learning procedure, was employed to facilitate patients’ meeting clearly defined and individualized attentiveness and participation goals during each session of a social skills training group. Primary outcome measures were observational ratings of attentiveness in each session and pre- and post-BCSM ratings of social skill and symptoms. Patients receiving social skills training augmented with AS demonstrated significantly more attentiveness in group sessions and higher levels of skill acquisition; moreover, significant relationships were found between changes in attentiveness and amount of skills acquired. Changes in attentiveness were unrelated to level or change in antipsychotic medication dose. AS is an effective example of supported cognition, in that cognitive abilities are improved within the environmental context where the patient is experiencing difficulty, leading to gains in both attention and functional outcome

Attention Shaping: a Reward-Based Learning Method to Enhance Skills Training Outcomes in Schizophrenia

Disturbances in sustained attention commonly interfere with the ability of persons with schizophrenia to benefit from evidence-based psychosocial treatments. Cognitive remediation interventions have thus far demonstrated minimal effects on attention, as have medications. There is thus a gap between the existence of effective psychosocial treatments and patients’ ability to effectively engage in and benefit from them. We report on the results of a multisite study of attention shaping (AS), a behavioral intervention for improving attentiveness and learning of social skills among highly distractible schizophrenia patients. Patients with chronic schizophrenia who were refractory to skills training were assigned to receive either the UCLA Basic Conversation Skills Module (BCSM) augmented with AS (n = 47) or in the standard format (n = 35). AS, a reward-based learning procedure, was employed to facilitate patients’ meeting clearly defined and individualized attentiveness and participation goals during each session of a social skills training group. Primary outcome measures were observational ratings of attentiveness in each session and pre- and post-BCSM ratings of social skill and symptoms. Patients receiving social skills training augmented with AS demonstrated significantly more attentiveness in group sessions and higher levels of skill acquisition; moreover, significant relationships were found between changes in attentiveness and amount of skills acquired. Changes in attentiveness were unrelated to level or change in antipsychotic medication dose. AS is an effective example of supported cognition, in that cognitive abilities are improved within the environmental context where the patient is experiencing difficulty, leading to gains in both attention and functional outcome

PGC-1α overexpression increases transcription factor EB nuclear localization and lysosome abundance in dystrophin-deficient skeletal muscle

Duchenne muscular dystrophy (DMD) is caused by the absence of functional dystrophin protein and results in progressive muscle wasting. Dystrophin deficiency leads to a host of dysfunctional cellular processes including impaired autophagy. Autophagic dysfunction appears to be due, at least in part, to decreased lysosomal abundance mediated by decreased nuclear localization of transcription factor EB (TFEB), a transcription factor responsible for lysosomal biogenesis. PGC‐1α overexpression decreased disease severity in dystrophin‐deficient skeletal muscle and increased PGC‐1α has been linked to TFEB activation in healthy muscle. The purpose of this study was to determine the extent to which PGC‐1α overexpression increased nuclear TFEB localization, increased lysosome abundance, and increased autophagosome degradation. We hypothesized that overexpression of PGC‐1α would drive TFEB nuclear translocation, increase lysosome biogenesis, and improve autophagosome degradation. To address this hypothesis, we delivered PGC‐1α via adeno‐associated virus (AAV) vector injected into the right limb of 3‐week‐old mdx mice and the contralateral limbs received a sham injection. At 6 weeks of age, this approach increased PGC‐1α transcript by 60‐fold and increased TFEB nuclear localization in gastrocnemii from PGC‐1α treated limbs by twofold compared to contralateral controls. Furthermore, lamp2, a marker of lysosome abundance, was significantly elevated in muscles from limbs overexpressing PGC‐1α. Lastly, increased LC3II and similar p62 in PGC‐1α overexpressing‐limbs compared to contralateral limbs are supportive of increased degradation of autophagosomes. These data provide mechanistic insight into PGC‐1α‐mediated benefits to dystrophin‐deficient muscle, such that increased TFEB nuclear localization in dystrophin‐deficient muscle leads to increased lysosome biogenesis and autophagy

Nutraceutical and pharmaceutical cocktails did not improve muscle function or reduce histological damage in D2-mdx mice

Progressive muscle injury and weakness are hallmarks of Duchenne muscular dystrophy. We showed previously that quercetin (Q) partially protected dystrophic limb muscles from disease-related injury. As quercetin activates PGC-1α through Sirtuin-1, an NAD+-dependent deacetylase, the depleted NAD+ in dystrophic skeletal muscle may limit quercetin efficacy, hence, supplementation with the NAD+ donor, nicotinamide riboside (NR), may facilitate quercetin efficacy. Lisinopril (Lis) protects skeletal muscle and improves cardiac function in dystrophin-deficient mice, therefore it was included in this study to evaluate the effects of lisinopril used with quercetin and NR. Our purpose was to determine the extent to which Q, NR, and Lis decreased dystrophic injury. We hypothesized that Q, NR or Lis alone would improve muscle function and decrease histological injury and when used in combination would have additive effects. Muscle function of 11-month-old DBA (healthy), D2-mdx (dystrophin-deficient), and D2-mdx mice was assessed following treatment with Q, NR, and/or Lis for 7-months. To mimic typical pharmacology of DMD patients a group was treated with prednisolone (Pred) in combination with Q, NR and Lis. At 11-months of age, dystrophin deficiency decreased specific tension and tetanic force in the soleus and extensor digitorum longus muscles and was not corrected by any treatment. Dystrophic muscle was more sensitive to contraction-induced injury, which was partially offset in the QNRLisPred group, while fatigue was similar between all groups. Treatments did not decrease histological damage. These data suggest treatment with Q, NR, Lis and Pred failed to adequately maintain dystrophic limb muscle function or decrease histological 46 damage

Mitochondria-localized AMPK responds to local energetics and contributes to exercise and energetic stress-induced mitophagy

Mitochondria form a complex, interconnected reticulum that is maintained through coordination among biogenesis, dynamic fission, and fusion and mitophagy, which are initiated in response to various cues to maintain energetic homeostasis. These cellular events, which make up mitochondrial quality control, act with remarkable spatial precision, but what governs such spatial specificity is poorly understood. Herein, we demonstrate that specific isoforms of the cellular bioenergetic sensor, 5′ AMP-activated protein kinase (AMPKα1/α2/β2/γ1), are localized on the outer mitochondrial membrane, referred to as mitoAMPK, in various tissues in mice and humans. Activation of mitoAMPK varies across the reticulum in response to energetic stress, and inhibition of mitoAMPK activity attenuates exercise-induced mitophagy in skeletal muscle in vivo. Discovery of a mitochondrial pool of AMPK and its local importance for mitochondrial quality control underscores the complexity of sensing cellular energetics in vivo that has implications for targeting mitochondrial energetics for disease treatment

Corrigendum: Identification of novel anti-amoebic pharmacophores from kinase inhibitor chemotypes

Acanthamoeba species, Naegleria fowleri, and Balamuthia mandrillaris are opportunistic pathogens that cause a range of brain, skin, eye, and disseminated diseases in humans and animals. These pathogenic free-living amoebae (pFLA) are commonly misdiagnosed and have sub-optimal treatment regimens which contribute to the extremely high mortality rates (>90%) when they infect the central nervous system. To address the unmet medical need for effective therapeutics, we screened kinase inhibitor chemotypes against three pFLA using phenotypic drug assays involving CellTiter-Glo 2.0. Herein, we report the activity of the compounds against the trophozoite stage of each of the three amoebae, ranging from nanomolar to low micromolar potency. The most potent compounds that were identified from this screening effort were: 2d (A. castellanii EC50: 0.92 ± 0.3 μM; and N. fowleri EC50: 0.43 ± 0.13 μM), 1c and 2b (N. fowleri EC50s: <0.63 μM, and 0.3 ± 0.21 μM), and 4b and 7b (B. mandrillaris EC50s: 1.0 ± 0.12 μM, and 1.4 ± 0.17 μM, respectively). With several of these pharmacophores already possessing blood–brain barrier (BBB) permeability properties, or are predicted to penetrate the BBB, these hits present novel starting points for optimization as future treatments for pFLA-caused diseases

Breastfeeding and depression: a systematic review of the literature

Background: Research has separately indicated associations between pregnancy depression and breastfeeding, breastfeeding and postpartum depression, and pregnancy and postpartum depression. This paper aimed to provide a systematic literature review on breastfeeding and depression, considering both pregnancy and postpartum depression. Methods: An electronic search in three databases was performed using the keywords: “breast feeding”, “bottle feeding”, “depression”, “pregnancy”, and “postpartum”. Two investigators independently evaluated the titles and abstracts in a first stage and the full-text in a second stage review. Papers not addressing the association among breastfeeding and pregnancy or postpartum depression, non-original research and research focused on the effect of antidepressants were excluded. 48 studies were selected and included. Data were independently extracted. Results: Pregnancy depression predicts a shorter breastfeeding duration, but not breastfeeding intention or initiation. Breastfeeding duration is associated with postpartum depression in almost all studies. Postpartum depression predicts and is predicted by breastfeeding cessation in several studies. Pregnancy and postpartum depression are associated with shorter breastfeeding duration. Breastfeeding may mediate the association between pregnancy and postpartum depression. Pregnancy depression predicts shorter breastfeeding duration and that may increase depressive symptoms during postpartum. Limitations: The selected keywords may have led to the exclusion of relevant references. Conclusions: Although strong empirical evidence regarding the associations among breastfeeding and pregnancy or postpartum depression was separately provided, further research, such as prospective studies, is needed to clarify the association among these three variables. Help for depressed pregnant women should be delivered to enhance both breastfeeding and postpartum psychological adjustment.This research was supported by FEDER Funds through the Programa Operacional Factores de Competitividade – COMPETE and by National Funds through FCT – Fundaçãopara a Ciência e a Tecnologiaunder the project: PTDC/SAU/SAP/116738/2010. The sponsors had no further role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication

Amamentação e depressão pós-parto: revisão do estado de arte

Objective: To review the literature on the association between breastfeeding and postpartum depression. Sources: A review of literature found on MEDLINE/ PubMed database. Summary of findings: The literature consistently shows that breastfeeding provides a wide range of benefits for both the child and the mother. The psychological benefits for the mother are still in need of further research. Some studies point out that pregnancy depression is one of the factors that may contribute to breastfeeding failure. Others studies also suggest an association between breastfeeding and postpartum depression; the direction of this association is still unclear. Breastfeeding can promote hormonal processes that protect mothers against postpartum depression by attenuating cortisol response to stress. It can also reduce the risk of postpartum depression, by helping the regulation of sleep and wake patterns for mother and child, improving mother’s self efficacy and her emotional involvement with the child, reducing the child’s temperamental difficulties, and promoting a better interaction between mother and child. Conclusions: Studies demonstrate that breastfeeding can protect mothers from postpartum depression, and are starting to clarify which biological and psychological processes may explain this protection. However, there are still equivocal results in the literature that may be explained by the methodological limitations presented by some studies.Objetivo: Revisar a literatura sobre a associação entre a amamentação e a depressão pós-parto. Fontes: Uma revisão da literatura encontrada na base de dados MEDLINE/Pub-Med. Resumo dos achados: A literatura mostra, de forma consistente, que a amamentação fornece uma ampla quantidade de benefícios tanto para a criança quanto para a mãe. Ainda são necessárias mais pesquisas sobre os benefícios psicológicos para a mãe. Alguns estudos apontam que a depressão na gravidez é um dos fatores que pode contribuir para a não amamentação. Outros estudos sugerem, também, uma associação entre amamentação e depressão pós-parto, não estando clara ainda a direção dessa associação. A amamentação pode promover processos hormonais que protegem as mães contra a depressão pós-parto por atenuar a resposta do cortisol ao estresse. E isso também pode reduzir o seu risco, por auxiliar na regulação dos padrões do sono e vigília da mãe e do filho, melhorando a autoeficácia e o envolvimento emocional da mãe com a criança, reduzindo as dificuldades de temperamento e promovendo uma melhor interação entre eles. Conclusões: A pesquisa aponta que a amamentação pode proteger as mães da depressão pós-parto e começa a esclarecer que processos biológicos e psicológicos podem explicar essa proteção. Contudo, ainda existem resultados ambíguos na literatura que poderão ser explicados pelas limitações metodológicas apresentadas por alguns estudos.Este trabalho foi financiado por fundos nacionais através do FCT/MCTES (PIDDAC) e da Comunidade Europeia (FEDER COMPETE): Breastfeeding and Postpartum Depression (PTDC/SAU-SAP/116738/2010)