Role of Regulatory T Cells in Skeletal Muscle Regeneration: A Systematic Review.

Muscle injuries are frequent in individuals with genetic myopathies and in athletes. Skeletal muscle regeneration depends on the activation and differentiation of satellite cells present in the basal lamina of muscle fibers. The skeletal muscle environment is critical for repair, metabolic and homeostatic function. Regulatory T cells (Treg) residing within skeletal muscle comprise a distinct and special cell population that modifies the inflammatory environment by secreting cytokines and amphiregulin, an epidermal growth factor receptor (EGFR) ligand that acts directly upon satellite cells, promoting tissue regeneration. This systematic review summarizes the current knowledge regarding the role of Treg in muscle repair and discusses their therapeutic potential in skeletal muscle injuries. A bibliographic search was carried out using the terms Treg and muscle regeneration and repair, covering all articles up to April 2021 indexed in the PubMed and EMBASE databases. The search included only published original research in human and experimental animal models, with further data analysis based on the PICO methodology, following PRISMA definitions and Cochrane guidelines.

Persistent mdx diaphragm alterations are accompanied by increased expression and activity of calcium and muscle-specific proteins.

The mdx mouse model of Duchenne Muscular Dystrophy (DMD) presents sarcolemma instability and develops a mild multi-stage dystrophinopathy characterized by intense myonecrosis with inflammatory infiltrate at 4-weeks; muscular regeneration at 12-weeks and persistent fibrosis onwards. Mdx diaphragm muscle has a more severe phenotype with structural and functional deterioration that closely resembles the diaphragm impairment responsible for DMD human patients' morbidity. Herein, we compared calcium deposits, activity of calcium-related proteases, and expression of muscle-specific proteins in mdx diaphragm at 4-weeks and 12-weeks. We found increased calcium deposits mainly at 12-weeks, concomitant with high activity of calpains and matrix metalloprotease-9, but decreased expression of Myh4 (Myhc IIb) and Atp2a1 (SERCA1), and high expression of the myogenic regulatory factors Myod1 and Myog. Our results suggest that increased calcium deposits and persistent activity of calcium dependent proteases throughout the disease are involved in the degeneration and regeneration processes in the mdx diaphragm.

Adjuvant effect of low-carbohydrate diet on outcomes of patients with recurrent glioblastoma under intranasal perillyl alcohol therapy.

BACKGROUND: Standard of care for glioblastoma (GB), consisting of cytotoxic chemotherapy, steroids, and high-dose radiation, induces changes in the tumor microenvironment through its effects on glucose availability, which is a determinant for tumor progression (TP). Low-carbohydrate diet (LCD) reduces the glucose levels needed to drive the Warburg effect. METHODS: To investigate LCD's effect on GB therapy, we have begun a clinical trial using LCD as an addition to intranasal perillyl alcohol (POH) for recurrent GB (rGB) patients. This study involved 29 individuals and evaluated, over a period of 1 year, the adjuvant effect of LCD associated with POH therapy in terms of toxicity, extent of peritumoral edema, reduced corticosteroid use, seizure frequency, and overall survival. POH group (n = 14) received solely intranasal POH without specific diet regimen, whereas POH/LCD group (n = 15) received intranasal POH in combination with nutritional intervention. Patients' assessment was based on clinical reviews and magnetic resonance data. RESULTS: In the 1-year follow-up, the POH/LCD group showed a 4.4-fold decrease in the proportion of patients who needed treatment with corticosteroids, as well as a reduction in tumor size and peritumoral edema, as compared to the POH group. While 75% of patients undergoing POH treatment experienced seizures, this fraction was reduced to 56% in the POH/LCD group. A 2.07-fold increase in the proportion of patients with stable disease, along with a 2.8-fold decrease in the proportion of patients with TP, was seen in the POH/LCD group. CONCLUSION: The results presented in this study show that the LCD associated with intranasal POH therapy may represent a viable option as adjunctive therapy for rGB to improve survival without compromising patients' quality of life. Prospective cohort studies are needed to confirm these findings and validate the efficacy of this novel therapeutic strategy.

The omentum harbors unique conditions in the peritoneal cavity to promote healing and regeneration for diaphragm muscle repair in mdx mice.

Although the primary cause of Duchenne muscular dystrophy (DMD) is a genetic mutation, the inflammatory response contributes directly to severity and exacerbation of the diaphragm muscle pathology. The omentum is a lymphoid organ with unique structural and immune functions serving as a sanctuary of hematopoietic and mesenchymal progenitors that coordinate immune responses in the peritoneal cavity. Upon activation, these progenitors expand and the organ produces large amounts of growth factors orchestrating tissue regeneration. The omentum of mdx mouse, a DMD murine model, is rich in milky spots and produces growth factors that promote diaphragm muscle regeneration. The present review summarizes the current knowledge of the omentum as an important immunologic structure and highlights its contribution to resolution of dystrophic muscle injury by providing an adequate environment for muscle regeneration, thus being a potential site for therapeutic interventions in DMD.

Liver fibrosis improvement in chronic hepatitis C after direct acting-antivirals is accompanied by reduced profibrogenic biomarkers-a role for MMP-9/TIMP-1.

BACKGROUND AND AIMS: Disturbances in matrix metalloproteinases (MMPs) and corresponding tissue inhibitors (TIMPs) contribute to hepatitis C virus (HCV)-induced fibrosis. This study aimed to determine MMP-9/TIMP-1 levels in addition to MMP-2 and -9 activities; correlating with the improvement of liver fibrosis in patients under direct-acting antiviral (DAA) therapy. METHODS: Clinical and laboratory follow-up were performed before treatment and after 12 weeks post-treatment, referred as sustained viral response (SVR). We evaluated liver function including non-invasive fibrosis measurements; MMP activity by zymography; and MMP-9/TIMP-1 complex, inflammatory and pro-fibrogenic mediators by immunoenzymatic assays. RESULTS: Cohort included 33 patients (59.5 ±â€¯9.3 years, 60.6% females) whose reached SVR and 11 control-paired subjects (42.5 ±â€¯15 years, 54.5% females). Before treatment, HCV patients presented higher MMP-9/TIMP-1 levels (P < 0.05) when compared to controls, and the highest values were observed in patients with fibrosis (P < 0.05). In addition, MMP-9/TIMP-1 levels were significantly reduced after DAA therapy (P < 0.0001) and were associated with profibrogenic biomarkers. No differences were observed for MMP-2 and -9 activities; however, these biomarkers were significantly associated with inflammatory mediators. CONCLUSION: Our data suggest that MMP-9/TIMP-1 complex can be a promising biomarker of active fibrogenesis, being able to identify the interruption of fibrosis progression after HCV eradication.

Dihydrofolate Reductase (DHFR) del19bp Polymorphism and Down Syndrome Offspring.

Down syndrome (DS) is the most common form of mental disability of genetic etiology. Nondisjunction of chromosome 21 is the leading cause of the syndrome. In general, free trisomy 21 cases originate from missegregation in maternal meiosis. Several reports have suggested an association between genetic variants in genes encoding folate metabolizing enzymes and the predisposition to chromosome missegregation. We have conducted a case-control study of 109 DS case mothers (MDS) and 248 control mothers (CM) to assess the association between DHFR del19bp polymorphism and an increased risk of bearing a DS child. Genomic DNA was extracted from buccal cells, and molecular analysis of DHFR del19pb polymorphism was performed by polymerase chain reaction (PCR). Both MDS and CM allelic and genotypic distributions were in Hardy-Weinberg equilibrium. The frequency of DHFR del19pb-mutated allele was 0.54 in MDS and 0.46 in CM. Overall analysis showed that the mutant allele was borderline associated with DS risk (OR 1.38; 95% CI 1.00-1.89; P = 0.05) and a weak positive association for del/del and/or wt/del genotypes of DHFR del19pb polymorphism compared to homozygous wt/wt genotype was identified (OR = 1.75; 95% CI 1.01-3.03; P = 0.05). When we have analyzed data stratified by age, there is an increased risk of bearing a DS child associated with the polymorphic allele (OR = 1.49; 95% CI 1.03-2.16; P = 0.03), suggesting that DHFR del 19-bp polymorphism could be an independent risk factor for DS in women aged < 40 years old.

Intranasal perillyl alcohol therapy improves survival of patients with recurrent glioblastoma harboring mutant variant for MTHFR rs1801133 polymorphism.

BACKGROUND: Polymorphisms in MTHFR gene influence risk and overall survival of patients with brain tumor. Global genomic DNA (gDNA) methylation profile from tumor tissues is replicated in peripheral leukocytes. This study aimed to draw a correlation between rs1801133 MTHFR variants, gDNA methylation and overall survival of patients with recurrent glioblastoma (rGBM) under perillyl alcohol (POH) treatment. METHODS: gDNA from whole blood was extracted using a commercially available kit (Axygen) and quantified by spectrophotometry. Global gDNA methylation was determined by ELISA and rs1801133 polymorphism by PCR-RFLP. Statistical analysis of gDNA methylation profile and rs1801133 variants included Mann-Whitney, Kruskal-Wallis, Spearman point-biserial correlation tests (SPSS and Graphpad Prism packages; significant results for effect size higher than 0.4). Prognostic value of gDNA methylation and rs1801133 variants considered survival profiles at 25 weeks of POH treatment, having the date of protocol adhesion as starting count and death as the final event. RESULTS: Most rGBM patients showed global gDNA hypomethylation (median = 31.7%) and a significant, moderate and negative correlation between TT genotype and gDNA hypomethylation (median = 13.35%; rho = - 0.520; p = 0.003) compared to CC variant (median = 32.10%), which was not observed for CT variant (median = 33.34%; rho = - 0.289; p = 0.06). gDNA hypermethylated phenotype (median = 131.90%) exhibited significant, moderate and negative correlations between TT genotype (median = 112.02%) and gDNA hypermethylation levels when compared to CC (median = 132.45%; rho = - 0,450; p = 0.04) or CT (median = 137.80%; rho = - 0.518; p = 0.023) variants. TT variant of rs1801133 significantly decreased gDNA methylation levels for both patient groups, when compared to CC (d values: hypomethylated = 1.189; hypermethylated = 0.979) or CT (d values: hypomethylated = 0.597; hypermethylated = 1.167) variants. Positive prognostic for rGBM patients may be assigned to gDNA hypermethylation for survivors above 25 weeks of treatment (median = 88 weeks); and TT variant of rs1801133 regardless POH treatment length. CONCLUSION: rGBM patients under POH-based therapy harboring hypermethylated phenotype and TT variant for rs1801133 had longer survival. Intranasal POH therapy mitigates detrimental effects of gDNA hypomethylation and improved survival of patients with rGBM harboring TT mutant variant for MTHFR rs1801133 polymorphism. TRIAL REGISTRATION: CONEP -9681- 25,000.009267 / 2004. Registered 12th July, 2004.

Perillyl alcohol and perillic acid exert efficient action upon HSV-1 maturation and release of infective virus.

BACKGROUND: Infection by herpes simplex type-1 virus (HSV-1) causes several pathological processes, including cutaneous, oral and genital infections, fatal encephalitis and cognitive dysfunction due to grey matter loss. Acyclovir is the reference compound used as HSV-1 antiviral therapy. However, with the emergence of HSV-resistant strains to current antiviral drugs, development of new antiviral agents with distinct modes of action is urgently needed. METHODS: In this study, we examined the mechanism of action of monoterpenes perillyl alcohol (POH) and perillic acid (PA) upon in vitro replication of HSV-1 KOS wild-type and the syn-mutant 17+ strain on Vero cells by plaque assay. RESULTS: The cytotoxicity of POH and PA was measured by MTT assay and indicated that both compounds had high anti-HSV-1 activities in a concentration range that was not toxic for Vero cells. In addition, PCR analysis showed that POH and PA did not inhibit viral genome replication, but rather the release of infective virion particles from Vero cells. CONCLUSIONS: Such findings suggest that POH and PA exert action upon late stages of HSV-1 maturation, therefore, indicating a promising perspective to its application in clinical investigation as effective anti-HSV-1 therapy preventing intermittent reactivation and progressive grey matter loss.

Comparative study of calcium and calcium-related enzymes with differentiation markers in different ages and muscle types in mdx mice.

Sarcolemma instability and increased calcium influx in muscle fibers are characteristics of the Duchenne muscular dystrophy. Excessive calcium activates calcium-dependent enzymes, such as calpains (CAPN) and matrix metalloproteases (MMP). Here, we analyzed calcium deposits, the activity of CAPN and MMP and the expression of Myh, SERCA and myogenic regulatory factors in different skeletal muscles during myonecrosis (4-weeks) and regeneration (12-weeks) phases of the mdx muscular pathology. Alizarin red staining was used to assess calcium deposits, casein and gelatin zymography were performed to evaluate CAPN and MMP activity, and qPCR was used to evaluate the expression of Myh, Capn, Atp2a1 and Atp2a2, Myod1 and Myog. We observed the following characteristics in mdx muscles: (i) calcium deposits almost exclusively in mdx muscles, (ii) lower CAPN1 activity in mdx muscles, (iii) higher CAPN2 activity in mdx muscles (only at 12 wks), (iv) autolyzed CAPN activity exclusively in mdx muscles, (v) lower expression of Capn1 and higher expression of Capn2 in mdx muscles; (vi) lower expression of Atp2a1 and Atp2a2 in mdx muscles, (vii) higher MMP (pre pro MMP2, pro MMP2, MMP2 and MMP9) activity in mdx muscles, (viii) MMP2 activity exclusively in mdx muscles at 12 wks, (ix) MMP9 activity exclusively in mdx muscles, (x) higher expression of Myog in mdx muscles at 12 wks, and (xi) lower expression of Myh (Myh7, Myh2, Myh1, Myh4) in mdx muscles, particularly Myh7 and Myh2. The collection of our results provides valuable information for a better characterization of mdx pathology phenotype.

Omentum acts as a regulatory organ controlling skeletal muscle repair of mdx mice diaphragm.

Duchenne muscular dystrophy is a lethal X-linked muscle wasting disease due to mutations of the dystrophin gene leading to distinct susceptibility to degeneration and fibrosis among skeletal muscles. This study aims at verifying whether intense mdx diaphragm remodeling could be attributed to influences from the omentum, a lymphohematopoietic tissue rich in progenitor cells and trophic factors. Mdx omentum produces growth factors HGF and FGF and increased amounts of VEGF with pleiotropic actions upon muscular progenitors and myoblast differentiation. Histology revealed that the absence of the omentum reduced inflammation and collagen deposition in the diaphragm. The diaphragm from omentectomized mdx mice presents impaired repair with a predominance of collagen type I deposition, decreased muscle regeneration and a reduction in collagen type IV and indication of altered basal lamina integrity in the diaphragm. Omentectomy further reduced inflammatory infiltration and NFκ-B activation but a change in the pattern of muscle inflammation with low numbers of the F4/80+CD206+ M-2 macrophage subset. Although omentectomized mice had high levels of Pax7, myogenin and TNF-α, the percentage of myofibers undergoing regeneration was low thus suggesting that a lack of the omentum halts the muscle differentiation program. Such results support that omentum exerts a regulatory function inducing an inflammatory process that favors regeneration and inhibits fibrosis selectively in the diaphragm muscle thus being a potential site for therapeutic interventions in DMD.

Reduced mitochondrial respiration and increased calcium deposits in the EDL muscle, but not in soleus, from 12-week-old dystrophic mdx mice.

Mitochondria play an important role in providing ATP for muscle contraction. Muscle physiology is compromised in Duchenne muscular dystrophy (DMD) and several studies have shown the involvement of bioenergetics. In this work we investigated the mitochondrial physiology in fibers from fast-twitch muscle (EDL) and slow-twitch muscle (soleus) in the mdx mouse model for DMD and in control C57BL/10J mice. In our study, multiple mitochondrial respiratory parameters were investigated in permeabilized muscle fibers from 12-week-old animals, a critical age where muscle regeneration is observed in the mdx mouse. Using substrates of complex I and complex II from the electron transport chain, ADP and mitochondrial inhibitors, we found in the mdx EDL, but not in the mdx soleus, a reduction in coupled respiration suggesting that ATP synthesis is affected. In addition, the oxygen consumption after addition of complex II substrate is reduced in mdx EDL; the maximal consumption rate (measured in the presence of uncoupler) also seems to be reduced. Mitochondria are involved in calcium regulation and we observed, using alizarin stain, calcium deposits in mdx muscles but not in control muscles. Interestingly, more calcium deposits were found in mdx EDL than in mdx soleus. These data provide evidence that in 12-week-old mdx mice, calcium is accumulated and mitochondrial function is disturbed in the fast-twitch muscle EDL, but not in the slow-twitch muscle soleus.

Circulating Cell-Free DNA as a Prognostic and Molecular Marker for Patients with Brain Tumors under Perillyl Alcohol-Based Therapy.

Tumor infiltration into brain tissue usually remains undetected even by high-resolution imaging. Molecular markers are used to increase diagnostic accuracy, but with limited continuous monitoring application. We evaluated the potential of circulating cell-free DNA (cfDNA) as a molecular indicator of the response to therapy by the intranasal administration (ITN) of perillyl alcohol (POH) in brain tumors. The cohort included 130 healthy subjects arranged as control-paired groups and patients at terminal stages with glioblastoma (GBM, n = 122) or brain metastasis (BM, n = 55) from stage IV adenocarcinomas. Serum cfDNA was isolated and quantified by fluorimetry. Compared with the controls (40 ng/mL), patients with brain tumors before ITN-POH treatment had increased (p < 0.0001) cfDNA median levels: GBM (286 ng/mL) and BM (588 ng/mL). ITN-POH treatment was significantly correlated (rho = -0.225; p = 0.024) with survival of >6 months at a concentration of 599 ± 221 ng/mL and of.

Efficacy of a ketogenic diet with concomitant intranasal perillyl alcohol as a novel strategy for the therapy of recurrent glioblastoma.

It has been hypothesized that persistent ketotic hypoglycemia represents a potential therapeutic strategy against high-grade gliomas. Perillyl alcohol (POH) is a non-toxic, naturally-occurring, hydroxylated monoterpene that exhibits cytotoxicity against temozolomide-resistant glioma cells, regardless of O6-methylguanine-methyltransferase promoter methylation status. The present study aimed to evaluate the toxicity and therapeutic efficacy of intranasal POH when administered in combination with a ketogenic diet (KD) program for the treatment of patients with recurrent glioblastoma. The 32 enrolled patients were divided into two groups, KD or standard diet, with intranasal POH treatment (n=17 and n=15, respectively). The nutritional status and anthropometric parameters of the patients were measured. Patients that adhered to the KD maintained a strict dietary regimen, in addition to receiving 55 mg POH four times daily, in an uninterrupted administration schedule for three months. Neurological examination and magnetic resonance imaging analysis were used to monitor disease progression. A total of 9/17 patients in the KD group survived and maintained compliance with the KD. After three months of well-tolerated treatment, a partial response (PR) was observed for 77.8% (7/9) of the patients, stable disease (SD) in 11.1% (1/9) and 11.1% (1/9) presented with progressive disease (PD). Among the patients assigned to the standard diet group, the PR rate was 25% (2/8 patients), SD 25% (2/8) and PD 50% (4/8 patients). The patients assigned to the KD group presented with reduced serum lipid levels and decreased low-density lipoprotein cholesterol levels. These results are encouraging and suggest that KD associated with intranasal POH may represent a viable option as an adjunct therapy for recurrent GBM.

Patient with Recurrent Glioblastoma Responding Favorably to Ketogenic Diet Combined with Intranasal Delivery of Perillyl Alcohol: A Case Report and Literature Review

Introduction Monoterpene perillyl alcohol (POH) is cytotoxic to temozolomideresistant glioma cells, regardless of its O6-methylguanine-methyltransferase (MGMT) promoter methylation status. Moreover, adherence to a ketogenic diet (KD) produced successful outcomes in preclinical and clinical studies in the glioma setting. Case Presentation A 54-year-old Caucasian man had a confirmed diagnosis of refractory glioblastoma multiforme (GBM). The immunohistochemical evaluation was negative for methylation, and failed to detect mutations in the isocitrate dehydrogenase (IDH) 1 and 2 genes. In January 2016, the patient was enrolled in a clinical trial combining daily intranasal delivery of POH in combination with a KD. The KD was administered concomitantly with inhalation of POH (55 mg, 4 times a day) in an uninterrupted administration schedule for 3 months. Results The combination treatment was well-tolerated. The nutritional status and anthropometric measurements of the patient were measured. Adherence to the KD was confirmed by measuring the levels of ketone bodies in the urine. Throughout the treatment, a reduced frequency of seizures was observed. After three months of adherence to the treatment, the patient presented with weight loss, reduced body fat, increased water retention, and a slight increase in bone and muscle mass. A follow-up magnetic resonance imaging (MRI) scan after 3 months of treatment revealed marked reduction of the enhancing lesion. Conclusion Intranasal delivery of POH combined with concomitant adherence to a KD appeared to have a beneficial therapeutic effect in a patient with recurrent GBM. Further studies are needed to evaluate the efficacy of this therapeutic strategy in a larger cohort of treatment-refractory GBM patients.

Introdução O monoterpeno álcool perílico (AP) é citotóxico para linhagens celulares de glioblastoma, independentemente do status do promotor de metilação O6-metilguaninametiltransferase (MGMT). Além disso, a adesão à dieta cetogênica (DC) produziu resultados bem sucedidos em desenho de estudos pré-clínicos e clínicos de glioma. Relato de Caso Homem, 54 anos, caucasiano, com diagnóstico de glioblastoma multiforme (GBM) recidivo. A avaliação imuno-histoquímica foi negativa para metilação e não detectou mutações do gene da isocitrato desidrogenase 1 e 2 (IDH1 IDH2). Em janeiro de 2016, o paciente foi inscrito em um ensaio clínico da administração intranasal diária do AP combinada a DC. A DC foi administrada concomitantemente com inalação de AP (55 mg, 4 vezes ao dia) em um cronograma de administração ininterrupto durante 3 meses. Resultados O tratamento combinado foi bem tolerado. O estado nutricional e as medidas antropométricas do paciente foram avaliadas. Aderência a DC foi confirmada pela presença de corpos cetônicos na urina. Ao longo do tratamento, observou-se redução da frequência de convulsões. Após três meses de adesão ao tratamento, o paciente apresentou perda de peso, redução da gordura corporal, melhor hidratação e um aumento discreto da massa óssea e muscular. O acompanhamento da ressonância magnética após 3 meses de tratamento revelou redução acentuada do volume da lesão. Conclusão A administração intranasal do AP combinada a DC sugere ter um efeito terapêutico benéfico em pacientes com GBM recorrente. São necessários mais estudos para avaliar a eficácia desta estratégia terapêutica em uma coorte maior de pacientes com GBM refratários.

Pattern of cardiotoxin-induced muscle remodeling in distinct TLR-4 deficient mouse strains.

Tissue damage triggers innate immune response mediated by Toll-like receptor 4 (TLR) that recognizes endogenous host danger molecules associated with cell death and tissue inflammation, although the precise role of TLR-4 signaling in muscle tissue repair is still uncertain. Previously, we observed that TLR-4 exerted a protective effect preventing excessive muscular damage induced by Bothrops jararacussu crude venom. This study aimed to evaluate the involvement of TLR-4 at early stages of muscular tissue remodeling in distinct mouse strains after injection of purified snake venom. Muscular injury was induced by injection of 25 µl (0.05 mg/ml) of cardiotoxin (CTX) from Naja mossambica in the gastrocnemius muscle of C3H/HeN (wild-type); C3H/HeJ mice that express a non-functional TLR-4 receptor, C57BL/6 and Tlr4 -/- (B6 background) mice. Comparing to control, Tlr4 -/- mice presented at early stages (3 DPI) of muscle injury mild inflammation with low MMP-9 activity, scarce macrophage infiltration and premature change to anti-inflammatory phenotype, low TNF-α mRNA levels and reduced myogenin expression, with low regeneration and tissue remodeling. The presence of more Ly6Cneg macrophages in Tlr4 -/- mice at 3 DPI indicates that TLR-4 may influence the differentiation into Ly6Cneg or likely affect proliferation of such cells in the muscle. The present study shows that TLR-4 deficiency and genetic background influence the outcome of muscular tissue repair in aseptic lesions and yet still maintaining some level of signaling in the TLR4-mutant mice.

Perillyl alcohol, a pleiotropic natural compound suitable for brain tumor therapy, targets free radicals.

Monoterpenes such as limonene and perillyl alcohol (POH) are promising natural compounds with pro-oxidant properties partly due to endoplasmic reticulum (ER) stress-induced cytotoxicity, and antioxidant activity owing to their activity as free radical scavengers, inhibition of coenzyme Q synthesis, activation of antioxidant-responsive elements (inducing detoxification enzymes) and induction of apoptosis. Activation of ER-stress responses generates reactive oxygen species (ROS), which are highly reactive free radicals mainly produced during mitochondrial electron transfer for adenosine triphosphate (ATP) synthesis. When cells are subjected to oxidative stress conditions, there is an accumulation of ROS that can lead to irreversible cell injury caused primarily by lipid peroxidation, protein aggregation and/or DNA damage. Malignant tumors, such as glioblastoma multiforme, display elevated rates of oxygen consumption, necrosis and abnormal structural microvasculature. Alterations in the tumor microenvironment are tightly linked to tumor progression and occur as a result of activation of complex signaling networks involving inter-clonal cooperation, cell-matrix interactions and an ongoing inflammatory response leading to genetic and epigenetic alterations. This review will focus on the pro- and anti-oxidant activities of POH, which are greatly dependent on the respective ROS levels within the tumor microenvironment and involve the ER stress response system. As well, some critical aspects of tumor-associated metabolic changes and the consequences of endogenous ROS production for tumor progression will be discussed.

Perillyl alcohol: Dynamic interactions with the lipid bilayer and implications for long-term inhalational chemotherapy for gliomas.

BACKGROUND: Gliomas display a high degree of intratumor heterogeneity, including changes in physiological parameters and lipid composition of the plasma membrane, which may contribute to the development of drug resistance. Biophysical interactions between therapeutic agents and the lipid components at the outer plasma membrane interface are critical for effective drug uptake. Amphipathic molecules such as perillyl alcohol (POH) have a high partition coefficient and generally lead to altered lipid acyl tail dynamics near the lipid-water interface, impacting the lipid bilayer structure and transport dynamics. We therefore hypothesized that glioma cells may display enhanced sensitivity to POH-induced apoptosis due to plasma membrane alterations, while in non-transformed cells, POH may be expelled through thermal agitation. METHODS: Interactions between POH and the plasma membrane was studied using molecular dynamics simulations. In this phase I/II trial, we set up to evaluate the clinical effectiveness of long-term (up to 5 years) daily intranasal administration of POH in a cohort of 19 patients with low-grade glioma (LGG). Importantly, in a series of clinical studies previously published by our group, we have successfully established that intranasal delivery of POH to patients with malignant gliomas is a viable and effective therapeutic strategy. RESULTS: POH altered the plasma membrane potential of the lipid bilayer of gliomas and prolonged intranasal administration of POH in a cohort of patients with LGG halted disease progression with virtually no toxicity. CONCLUSION: Altogether, the results suggest that POH-induced alterations of the plasma membrane might be contributing to its therapeutic efficacy in preventing LGG progression.

Característica clínica e topográfica do glioma maligno em adolescente - Influência do tratamento intranasal com álcool perílico / Clinical and topographic characteristics of primary glioma in youth - Influence the response to perillyl alcohol treatment

Objetivo: Analisar a influência da topografia da lesão tumoral na resposta ao tratamento intranasal com álcool perílico (POH) em jovens com glioma maligno recidivo. Método: Tendo como padrão a faixa etária de 0 a 19 anos, foram incluídos pacientes do sexo masculino (#153; #31) e feminino (#178) com glioma maligno em estágio terminal, recebendo terapia de suporte paliativa e administração intranasal diária de 440 mg de POH. Resultados: Cefaleia intensa, tontura, vômito, crise convulsiva, alteração de comportamento, fraqueza muscular, alteração visual e hemiplegia à direita foram os sintomas prevalentes antes da confirmação diagnóstica de glioma. Análise de imagem mostrou lesão tumoral nas regiões troncocerebral (#153), talamomesencefálica esquerda (#178) e frontotemporal e insular direita (#31). Paciente #178 não respondeu ao tratamento, evoluindo a óbito em três semanas, e paciente #31 permaneceu em tratamento com POH por aproximadamente 54 semanas. Apesar de nova recidiva, paciente #153 apresenta doença estável, sem qualquer evidência clínica de recorrência para mais de 200 semanas em tratamento exclusivo com álcool perílico por via intranasal. Conclusão: Pacientes adolescentes com glioma maligno recidivo apresentaram heterogeneidade de sintomas compatível coma região anatômica comprometida, indicando que a topografia da lesão tumoral foi um fator prognóstico de sobrevida, influenciando inclusive na resposta ao tratamento intranasal com o álcool perílico.

Objective: Analyze the influence of tumor topography on response to intranasal perillyl (POH) treatment in youths with high grade glioma. Method: It was included male patients (#153; #31) with 19 years old and female (#178) with 15 years old with recurrent high grade glioma in terminal stage using supportive therapy and 440 mg POH daily intranasal administration. It was established a relation of clinical data and topographic image with therapeutic response to intranasal POH. Results: Intense headache, dizziness, vomiting, seizures, behavior change, muscle weakness, visual changes and right hemiplegia were the symptoms prevalent before the diagnostic confirmation of glioma. Image analysis showed tumoral lesionin the brain-stem (#153), in the left thalamus-mesencephalic region (#178), and right frontal-temporal and insular regions (#31). Patient #178 did not respond to intranasal POH treatment and rapidly progressed to death within 3 weeks; patient #31 remained in treatment with POH for nearly 54 weeks, and despite new recurrence, patient #153 presents stable disease, without any clinical evidence of recurrence for more than 200 weeks and under treatment exclusively with POH by intranasal route. Conclusion: Childhood patients with high grade malignant glioma had heterogeneity of clinical symptoms compatible with anatomical compromised region indicating that topography of the tumoral lesion was a prognostic factor influencing the overall survival and response to intranasal POH.

Implant of polymer containing pentacyclic triterpenes from Eugenia punicifolia inhibits inflammation and activates skeletal muscle remodeling.

Sustained chronic inflammation induces activation of genes involved in cellular proliferation and apoptosis, thereby causing skeletal muscle degeneration. To investigate in vitro effects of isolated pentacyclic triterpenes from Eugenia punicifolia (Ep-CM) upon signaling pathways involved in the regulation of skeletal muscle cell line proliferation, and in vivo muscular tissue remodeling. C2C12 cells were seeded on eight-well plates and [(3)H]-thymidine incorporation, TUNEL assays, mitochondria viability, zymography for matrix metalloproteases (MMPs), Western blot analysis for MAPKinase signaling pathway, NFκB activation and HMGB1 production subsequently determined under basal conditions and after Ep-CM treatment. A polymer containing Ep-CM was implanted on the volar surface of gastrocnemius muscles subjected to acute injury induced by bupivacaine for local slow and gradual release of bioactive compounds, and mice killed 4 days after surgery. Ep-CM inhibited proliferation of C2C12 myoblast cell line in a dose-dependent manner, confirmed by reduction of [(3)H]-thymidine uptake without affecting cell viability or inducing apoptosis. The cytostatic effect of Ep-CM occurred mainly via inhibition of phosphorylated extracellular signal-regulated kinase (pERK) activation and DNA synthesis, possibly inhibiting the G1 phase of the cell cycle, since Ep-CM increased pAkt and p27(kip1) but reduced Cyclin D1. Ep-CM in vitro treatment increased MMP-9 and MMP-2 activities of C2C12 myoblast cells, but reduced in vivo MMP-9 activity and acute muscular inflammation. Besides cytostatic and anti-inflammatory effects, Ep-CM pentacyclic triterpenes also contributed to degradation of basement membrane components by activating mechanisms of skeletal muscle remodeling in response to local injury.

Selective activation of α7 nicotinic acetylcholine receptor (nAChRα7) inhibits muscular degeneration in mdx dystrophic mice.

Amount evidence indicates that α7 nicotinic acetylcholine receptor (nAChRα7) activation reduces production of inflammatory mediators. This work aimed to verify the influence of endogenous nAChRα7 activation on the regulation of full-blown muscular inflammation in mdx mouse with Duchenne muscular dystrophy. We used mdx mice with 3 weeks-old at the height myonecrosis, and C57 nAChRα7(+/+) wild-type and nAChRα7(-/-) knockout mice with muscular injury induced with 60µL 0.5% bupivacaine (bp) in the gastrocnemius muscle. Pharmacological treatment included selective nAChRα7 agonist PNU282987 (0.3mg/kg and 1.0mg/kg) and the antagonist methyllycaconitine (MLA at 1.0mg/kg) injected intraperitoneally for 7 days. Selective nAChRα7 activation of mdx mice with PNU282987 reduced circulating levels of lactate dehydrogenase (LDH, a marker of cell death by necrosis) and the area of perivascular inflammatory infiltrate, and production of inflammatory mediators TNFα and metalloprotease MMP-9 activity. Conversely, PNU282987 treatment increased MMP-2 activity, an indication of muscular tissue remodeling associated with regeneration, in both mdx mice and WTα7 mice with bp-induced muscular lesion. Treatment with PNU282987 had no effect on α7KO, and MLA abolished the nAChRα7 agonist-induced anti-inflammatory effect in both mdx and WT. In conclusion, nAChRα7 activation inhibits muscular inflammation and activates tissue remodeling by increasing muscular regeneration. These effects were not accompanied with fibrosis and/or deposition of non-functional collagen. The nAChRα7 activation may be considered as a potential target for pharmacological strategies to reduce inflammation and activate mechanisms of muscular regeneration.