Preliminary insights into RNA in CSF of pediatric SMA patients after 6 months of nusinersen

BACKGROUND

Spinal muscular atrophy (SMA) is a rare autosomal-recessive neurodegenerative disorder caused by mutations in survival motor neuron 1 (SMN1) gene, and consequent loss of function of SMN protein, which results in progressive loss of lower motor neurons, and muscular wasting. Antisense oligonucleotide (ASO) nusinersen (Spinraza®) modulates the pre-mRNA splicing of the SMN2 gene, allowing rebalance of biologically active SMN. It is administered intrathecally via lumbar puncture after removing an equal amount of cerebrospinal fluid (CSF). Its effect was proven beneficial and approved since 2017 for SMA treatment. Given the direct effect of nusinersen on RNA metabolism, the aim of this project was to evaluate cell-free RNA (cfRNA) in CSF of SMA patients under ASOs treatment for biomarker discovery.

METHODS

By RNA-sequencing approach, RNA obtained from CSF of pediatric SMA type 2 and 3 patients was processed after 6 months of nusinersen treatment, at fifth intrathecal injection (T6), and compared to baseline (T0).

RESULTS

We observed the deregulation of cfRNAs in patients at T6 and we were able to classify these RNAs into disease specific, treatment specific and treatment dependent. Moreover, we subdivided patients into "homogeneous" and "heterogeneous" according to their gene expression pattern. The "heterogeneous" group showed peculiar activation of genes coding for ribosomal components, meaning that in these patients a different molecular effect of nusinersen is observable, even if this specific molecular response was not referable to a clinical pattern.

CONCLUSIONS

This study provides preliminary insights into modulation of gene expression dependent on nusinersen treatment and lays the foundation for biomarkers discovery.

Melatonin for prevention of acute kidney injury in patients treated with intravenous polymyxin B: a double-blind, placebo-controlled randomized clinical trial

OBJECTIVES

To evaluate the effect of melatonin versus placebo on the incidence of acute kidney injury (AKI) in patients treated with polymyxin B.

METHODS

We performed a single-centre, double-blind, randomized clinical trial (NCT03725267) of 30-mg oral melatonin versus placebo for patients treated with intravenous polymyxin B. Patients aged ≥18 years receiving polymyxin B for ≤48 hours were eligible. Melatonin or placebo pills were administered until the end of polymyxin B treatment or for a maximum of 14 days. The main outcome was any level of AKI.

RESULTS

Eighty-eight patients were randomized: 44 in the melatonin group and 44 in the placebo group. The study ended prematurely because of polymyxin B shortage during the COVID-19 pandemic. The patients' mean age was 63.6 ± 17.3 years, and 60.2% of the patients were men. Forty-six (52.3%, 23 in each group) patients developed AKI during the follow-up period. The incidence rate of AKI was 81.9/1000 and 77.4/1000 patients per day in melatonin and placebo groups, respectively (hazard ratio, 1.09; 95% CI, 0.61-1.94; p 0.78). Renal failure and 30-day mortality were similar between the groups. Moreover, the incidence of AKI was not different in pre-specified sub-groups.

DISCUSSION

Melatonin initiated in the first 48 hours of therapy did not reduce the incidence of AKI in patients treated with polymyxin B.

Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow

Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.

Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A

Previous detections of individual astrophysical sources of neutrinos are limited to the Sun and the supernova 1987A, whereas the origins of the diffuse flux of high-energy cosmic neutrinos remain unidentified. On 22 September 2017, we detected a high-energy neutrino, IceCube-170922A, with an energy of ~290 tera–electron volts. Its arrival direction was consistent with the location of a known γ-ray blazar, TXS 0506+056, observed to be in a flaring state. An extensive multiwavelength campaign followed, ranging from radio frequencies to γ-rays. These observations characterize the variability and energetics of the blazar and include the detection of TXS 0506+056 in very-high-energy γ-rays. This observation of a neutrino in spatial coincidence with a γ-ray–emitting blazar during an active phase suggests that blazars may be a source of high-energy neutrinos.

Search for γ-Ray Line Signals from Dark Matter Annihilations in the Inner Galactic Halo from 10 Years of Observations with H.E.S.S

Spectral lines are among the most powerful signatures for dark matter (DM) annihilation searches in very-high-energy γ rays. The central region of the Milky Way halo is one of the most promising targets given its large amount of DM and proximity to Earth. We report on a search for a monoenergetic spectral line from self-annihilations of DM particles in the energy range from 300 GeV to 70 TeV using a two-dimensional maximum likelihood method taking advantage of both the spectral and spatial features of the signal versus background. The analysis makes use of Galactic center observations accumulated over ten years (2004-2014) with the H.E.S.S. array of ground-based Cherenkov telescopes. No significant γ-ray excess above the background is found. We derive upper limits on the annihilation cross section ⟨σv⟩ for monoenergetic DM lines at the level of 4×10^{-28}  cm^{3} s^{-1} at 1 TeV, assuming an Einasto DM profile for the Milky Way halo. For a DM mass of 1 TeV, they improve over the previous ones by a factor of 6. The present constraints are the strongest obtained so far for DM particles in the mass range 300 GeV-70 TeV. Ground-based γ-ray observations have reached sufficient sensitivity to explore relevant velocity-averaged cross sections for DM annihilation into two γ-ray photons at the level expected from the thermal relic density for TeV DM particles.

P2X7 receptor as predictor gene for glioma radiosensitivity and median survival

Glioblastoma multiforme (GBM) is considered the most lethal intracranial tumor and the median survival time is approximately 14 months. Although some glioma cells present radioresistance, radiotherapy has been the mainstay of therapy for patients with malignant glioma. The activation of P2X7 receptor (P2X7R) is responsible for ATP-induced death in various cell types. In this study, we analyzed the importance of ATP-P2X7R pathway in the radiotherapy response P2X7R silenced cell lines, in vivo and human tumor samples. Both glioma cell lines used in this study present a functional P2X7R and the P2X7R silencing reduced P2X7R pore activity by ethidium bromide uptake. Gamma radiation (2Gy) treatment reduced cell number in a P2X7R-dependent way, since both P2X7R antagonist and P2X7R silencing blocked the cell cytotoxicity caused by irradiation after 24h. The activation of P2X7R is time-dependent, as EtBr uptake significantly increased after 24h of irradiation. The radiotherapy plus ATP incubation significantly increased annexin V incorporation, compared with radiotherapy alone, suggesting that ATP acts synergistically with radiotherapy. Of note, GL261 P2X7R silenced-bearing mice failed in respond to radiotherapy (8Gy) and GL261 WT-bearing mice, that constitutively express P2X7R, presented a significant reduction in tumor volume after radiotherapy, showing in vivo that functional P2X7R expression is essential for an efficient radiotherapy response in gliomas. We also showed that a high P2X7R expression is a good prognostic factor for glioma radiosensitivity and survival probability in humans. Our data revealed the relevance of P2X7R expression in glioma cells to a successful radiotherapy response, and shed new light on this receptor as a useful predictor of the sensitivity of cancer patients to radiotherapy and median survival.

23 NEONATAL SUPPORT THERAPY AND BLOOD GAS EVALUATION IN CLONED AND ARTIFICIAL INSEMINATION-DERIVED NEWBORN CALVES

Offspring derived from artificial reproductive techniques are already known to present several postnatal undesirable phenotypes and clinical disorders. Despite its benefits, cloning by somatic cell nuclear transfer (SCNT) is extremely inefficient. The birth rate in cattle is around 5% of the transferred blastocysts, and ~50% of delivered calves die in the first 48 h. Neonatal respiratory distress is reported to be one of the main causes of such deaths. Veterinary intervention is often needed to promote or improve blood oxygenation, avoiding respiratory acidosis and improving carbon dioxide delivery from blood/lungs to the environment. This study aimed to evaluate a neonatal support therapy over the blood gas and acid-base balance on newborn calves derived from SCNT or AI. Four cloned and 3 AI-derived calves delivered by Caesarean section were used for the experiment. Postnatal therapeutic procedures were comprised 4 doses of 400 mg of intratracheal surfactant every 15 min, 25 mg of oral sildenafil every 8 h for 3 days, and 5 L min–1 intranasal oxygen. Blood collections were performed within 30 min (T0), at 12 (T12), 24 (T24) and 48 (T48) hours after delivery. Blood samples were collected from the caudal auricular artery with a butterfly and a blood gas syringe. Oxygen saturation (sO2), arterial pressure of oxygen (PaO2) and carbon dioxide (PaCO2), pH, and bicarbonate (HCO3–) were evaluated with a portable blood gas analyzer (i-STAT, Abbott Point of Care Inc., Princeton, NJ, USA). Data obtained were submitted to ANOVA (Proc MIXED; SAS/STAT, version 9; SAS Institute Inc., Cary, NC, USA). There were significant differences between groups in blood pH (P = 0.0182) and between groups (P = 0.0281) and time of collection (P = 0.0303) in blood bicarbonate (HCO3–). The AI calves were born with normal pH (7.468 ± 0.033) and the cloned calves were born in acidosis (7.216 ± 0.166). These calves were stabilised in T48 (7.427 ± 0.017) using their own HCO3– that increased over time. Although there were no differences in sO2 (P = 0.4525), PaO2 (P = 0.3086), or PaCO2 (P = 0.2514), sO2 and PaO2 were numerically increased at the same time that PaCO2 decreased in both groups. In the cloned calves, the sO2, PaO2, and PaCO2 at T0 were 61.3 ± 28.6%, 39.8 ± 18.5 mmHg, and 65.8 ± 29.3 mmHg, respectively and reached 90.0 ± 3.4%, 57.7 ± 15.8 mmHg, and 42.0 ± 3.7 mmHg. In the AI calves, T0 blood gas analysis were 79.8 ± 19.4%, 56.1 ± 42.1 mmHg, and 39.1 ± 4.8 mmHg, and at T48 were 89.0 ± 2.6%, 82.3 ± 43.5 mmHg, and 43.0 ± 4.9 mmHg for sO2, PaO2, and PaCO2 respectively. The neonate support therapy improved calves' oxygenation and helped to eliminate the carbon dioxide from the blood. In our experience, the neonatal treatment was essential in supporting the lives of the cloned calves.Funding support was received from FAPESP 2011/19543–9.

Maturação in vitro de oócitos bovinos em meios suplementados com quercetina e seu efeito sobre o desenvolvimento embrionário

A quercetina é um flavonoide, amplamente encontrada em frutas, vegetais, grãos, flores, com elevada concentração no vinho tinto, e tem sido caracterizada funcionalmente pela atividade antioxidante. Para avaliação da maturação nuclear e do desenvolvimento embrionário bovino, os oócitos foram maturados por 22h na presença de quercetina (0,4, 2, 10 e 50µM), cisteamina (100µM) e na ausência dos antioxidantes. Os oócitos maturados foram corados com Hoechst para avaliação da maturação in vitro. Para avaliação do desenvolvimento embrionário, os oócitos foram fertilizados e cultivados in vitro, as taxas de desenvolvimento embrionário foram determinadas no sétimo dia de cultivo e o percentual de eclosão e o número de células dos embriões no oitavo dia. Os níveis de glutationa (GSH) dos oócitos foram mensurados por emissão de fluorescência com CMF2HC. A porcentagem de maturação nuclear (±89%) não diferiu entre os grupos. O desenvolvimento embrionário variou entre os tratamentos, o percentual de blastocisto foi superior (P<0,05) nos grupos tratados com 0,4, 2, 10 e 50∝M de quercetina (56,9, 59,5, 53,6 e 49,6%, respectivamente) e com 100∝M de cisteamina (50,4%) em relação ao grupo controle (42,3%). Na comparação entre os dois antioxidantes, a quercetina (0,4 e 2µM) foi superior na produção de embriões (56,9 e 59,5%, respectivamente) em comparação com cisteamina (50,4%). As taxas de embriões eclodidos foram similares (P>0,05) entre os grupos (±63,0%). O número médio de células dos embriões também foi similar entre os grupos (±233). Os níveis intracelulares de GSH foram superiores nos oócitos maturados com cisteamina, mas similares entre os oócitos tratados com quercetina e o controle. A suplementação da maturação in vitro com antioxidantes melhora as taxas de blastocistos. A quercetina foi superior à cisteamina, que, por sua vez, foi superior ao controle. Mas os níveis de GSH foram superiores somente nos oócitos tratados com cisteamina.

Functional and molecular characterization of kinin B1 and B 2 receptors in human bladder cancer: implication of the PI3Kγ pathway

Kinins and their receptors have been recently implicated in cancer. Using functional and molecular approaches, we investigated the relevance of kinin B1 and B2 receptors in bladder cancer. Functional studies were conducted using bladder cancer cell lines, and human biopsies were employed for molecular studies. Both B1 des-Arg(9)-BK and B2 BK receptor agonists stimulated the proliferation of grade 3-derived T24 bladder cancer cells. Furthermore, treatment with B1 and B2 receptor antagonists (SSR240612 and HOE140) markedly inhibited the proliferation of T24 cells. Only higher concentrations of BK increased the proliferation of the grade 1 bladder cancer cell line RT4, while des-Arg(9)-BK completely failed to induce its proliferation. Real-time PCR revealed that the mRNA expression of kinin receptors, particularly B1 receptors, was increased in T24 cells relative to RT4 cells. Data from bladder cancer human biopsies revealed that B1 receptor expression was increased in all tumor samples and under conditions of chronic inflammation. We also show novel evidence demonstrating that the pharmacological inhibition of PI3Kγ (phosphatidylinositol 3-kinase) with AS252424, concentration-dependently reduced T24 cell proliferation induced by BK or des-Arg(9)-BK. Finally, the incubation of T24 cells with kinin agonists led to a marked activation of the PI3K/AKT and ERK 1/2 signaling pathways, whereas p38 MAP kinase remained unaffected. Kinin receptors, especially B1 receptors, appear to be implicated in bladder cancer progression. It is tempting to suggest that selective kinin antagonists might represent potential alternative therapies for bladder cancer.

Previous treatment with ebselen and vitamin E alters adenine nucleotide hydrolysis in platelets from adult rats experimentally demyelinated with ethidium bromide

Many aspects of the relationship between the demyelinating pathology and platelet function need to be elucidated. Thus, the activity of NTPDase and 5'-nucleotidase enzymes was analyzed in platelets from rats demyelinated with ethidium bromide (EB) and previously treated with ebselen (Ebs) and vitamin E (Vit. E). The animals were divided into four groups: for ebselen, the groups were: I-control (saline), II-(saline and Ebs), III-(EB) and IV-(EB and Ebs); and for vitamin E, the groups were: I - control (saline), II-(saline and Vit. E), III-(EB) and IV-(EB and Vit. E). After 3 and 21 days, the blood was collected and the platelets were separated for enzymatic assays. For the treatment with Ebs, the NTPDase activity for ATP substrate was significantly lower in groups II, III and IV (p < 0.05) after 3 days, while after 21 days, a reduction was observed in group III (p < 0.05). ADP hydrolysis was reduced in group II (p < 0.05) and increased in group IV (p < 0.05) after 3 days, while after 21 days there was an increase in group IV (p < 0.05). In the treatment with Vit. E, ATP hydrolysis was lower in groups II, III and IV (p < 0.05) after 3 and 21 days. ADP hydrolysis was increased in group II (p < 0.05) after 3 days, and in group IV (p < 0.05) after 21 days. However, 5'-nucleotidase activity was not altered by the treatments. These findings demonstrate that NTPDase activity in platelets is diminished in demyelinating events and the treatments with Ebs and Vit. E modulated adenine nucleotide hydrolysis.

Activities of enzymes that hydrolyze adenine nucleotides in platelets from rats experimentally demyelinated with ethidium bromide and treated with interferon-beta

The activities of the enzymes NTPDase (EC 3.6.1.5, apyrase, CD39) and 5'-nucleotidase (EC 3.1.3.5, CD73) were analyzed in platelets from rats submitted to demyelination by ethidium bromide (EB) and treated with interferon beta (IFN-beta). The following groups were studied: I - control (saline), II - (saline and IFN-beta), III - (EB) and IV - (EB and IFN-beta). After 7, 15 and 30 days, the animals (n=7) were sacrificed and the platelets were separated by the method of Lunkes et al. [Lunkes, G., Lunkes D., Morsch, V., Mazzanti, C., Morsch, A., Miron, V., Schetinger, M.R.C., 2004. NTPDase and 5'-nucleotidase in rats alloxan- induced diabetes. Diabetes Research and Clinical Practice 65, 1-6]. NTPDase activity for ATP and ADP substrates was significantly lower in groups II and III after seven days, when compared to control (p<0.001). At fifteen days, ATP hydrolysis was significantly lower in group III and IV and higher in group II (p<0.001), while there was an activation of ADP hydrolysis in group II (p<0.001), when compared with the control. 5'-nucleotidase activity was significantly higher in group IV (p<0.001) after seven days, and lower in the groups III and IV (p<0.001) after fifteen days in relation to the control. No significant differences were observed in NTPDase and 5'-nucleotidase activities after thirty days. In conclusion, our study demonstrated that the hydrolysis of adenine nucleotides is modified in platelets of rats demyelinated and treated with IFN-beta.

Variable Very-High-Energy Gamma-Ray Emission from the Microquasar LS I +61 303

Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.

Apyrase and 5'-nucleotidase activities in synaptosomes from the cerebral cortex of rats experimentally demyelinated with ethidium bromide and treated with interferon-beta

Apyrase and 5'-nucleotidase activities were analyzed in an ethidium bromide (EB) demyelinating model associated with interferon-beta (IFN-beta). The animals were divided in groups: I, control (saline); II, saline and IFN-beta; III, EB and IV, EB and IFN-beta. After 7, 15 and 30 days the animals (n = 5) were sacrificed and the cerebral cortex was removed for synaptosome preparation and enzymatic assays. Apyrase activity using ATP as substrate increased in groups II, III and IV (P < 0.001) after 7 days and in groups III and IV (P < 0.001) after 15 days. Using ADP as substrate, an activation of this enzyme was observed in group III (P < 0.05) after seven and 15 days. The 5'-nucleotidase activity increased in group III (P < 0.05) after 7 days and in groups II, III and IV (P < 0.001) after 15 days. After 30 days treatment, no significant alteration was observed in enzyme activities. Results showed that apyrase and 5'-nucleotidase activities are altered in demyelination events and that IFN-beta was able to regulate the adenine nucleotide hydrolysis.

Enzymes that hydrolyze adenine nucleotides in platelets from breast cancer patients

The activities of NTPDase (EC 3.6.1.5, apyrase, CD39) and 5'-nucleotidase (EC 3.1.3.5, CD73) enzymes were analyzed in platelets from breast cancer patients. Initially, patients were compared in terms of length (years) of tamoxifen use. The following groups were studied: breast cancer patients who did not use tamoxifen, patients using tamoxifen for 1-48 months, patients using tamoxifen for 49-84 months, and controls (healthy subjects). Results demonstrated that adenosine triphosphate (ATP) hydrolysis was enhanced (F(3,114)=8.53; P<0.001) and adenosine diphosphate (ADP) hydrolysis was reduced (F(3,106)=5.09, P=0.002) as a function of tamoxifen use, while adenosine monophosphate (AMP) hydrolysis was unchanged. Next, patients were compared statistically according to disease stage, determined by the tumor-node-metastasis (TNM) staging system for classifying breast tumor. ATP hydrolysis was significantly elevated in patients with stage I and II breast cancer (F(4,113)=4.35; P=0.003), but was normal in patients with stage III and IV cancer. ADP hydrolysis was reduced in stages II to IV (F(4,105)=3.88, P=0.006) and AMP hydrolysis was elevated in stage II (F(4,105)=3.45 P=0.01), but was normal in stages III and IV. Platelet aggregation time was similar in all patients regardless of tamoxifen use or disease stage. Prothrombin time (PT) and activated partial thromboplastin time (APTT) were also within the normal range and similar among all groups. Similarly, fibrinogen and fibrin degradation product (FDP) were unchanged in all groups. In conclusion, our study demonstrated for the first time that hydrolysis of adenine nucleotides is modified in platelets from breast cancer patients taking tamoxifen.