Automated Food-Procuring Movement-Related Neuronal Activity in the Basolateral Amygdala of the Rat

We studied the impulse activity of neurons of the basal and lateral amygdalar nuclei generated when experimental animals (rats) performed fast stereotyped food-procuring movements by the forelimb. Within the basolateral amygdala, there are neurons whose activity is related to different stages of getting off the food, and according to the characteristics of their spiking these neurons should be divided into a number of subpopulations. Activation forestalling the movement initiation by 0.5-1.0 sec was observed in most neurons of the basolateral amygdala; this is considered a manifestation of excitation related to a motivation component of the food-procuring behavior. Activation of amygdalar neurons following movement initiation can result from generation in this structure of additional excitation necessary for successful performance of a complete food-procuring motor cycle.     

Small Molecular Inhibitors Block TRPM4 Currents in Prostate Cancer Cells,with Limited Impact on Cancer Hallmark Functions

Transient receptor potential melastatin 4 (TRPM4) is a broadly expressed Ca²⁺ activated monovalent cation channel that contributes to the pathophysiology of several diseases.For this study, we generated stable CRISPR/Cas9 TRPM4 knockout (K.O.) cells from the human prostate cancer cell line DU145 and analyzed the cells for changes in cancer hallmark functions. Both TRPM4-K.O. clones demonstrated lower proliferation and viability compared to the parental cells. Migration was also impaired in the TRPM4-K.O. cells. Additionally, analysis of 210 prostate cancer patient tissues demonstrates a positive association between TRPM4 protein expression and local/metastatic progression. Moreover, a decreased adhesion rate was detected in the two K.O. clones compared to DU145 cells.Next, we tested three novel TRPM4 inhibitors with whole-cell patch clamp technique for their potential to block TRPM4 currents. CBA, NBA and LBA partially inhibited TRPM4 currents in DU145 cells. However, none of these inhibitors demonstrated any TRPM4-specific effect in the cellular assays.To evaluate if the observed effect of TRPM4 K.O. on migration, viability, and cell cycle is linked to TRPM4 ion conductivity, we transfected TRPM4-K.O. cells with either TRPM4 wild-type or a dominant-negative mutant, non-permeable to Na⁺. Our data showed a partial rescue of the viability of cells expressing functional TRPM4, while the pore mutant was not able to rescue this phenotype. For cell cycle distribution, TRPM4 ion conductivity was not essential since TRPM4 wild-type and the pore mutant rescued the phenotype.In conclusion, TRPM4 contributes to viability, migration, cell cycle shift, and adhesion; however, blocking TRPM4 ion conductivity is insufficient to prevent its role in cancer hallmark functions in prostate cancer cells.     

EXO5-DNA structure and BLM interactions direct DNA resection critical for ATR-dependent replication restart

1. Download : Download high-res image (222KB)
2. Download : Download full-size image

     

M(en)TORship lessons on life and death by the integrated stress response

Cells employ pro-survival and pro-adaptive pathways to cope with different forms of environmental stress. When stress is excessive, and the damage caused by it is unsustainable, cells engage pro-death pathways, which are in place to protect the host from the deleterious effects of harmed cells. Two important pathways that determine the balance between survival and death of stressed cells are the integrated stress response (ISR) and the mammalian target of rapamycin (mTOR), both of which converge at the level of mRNA translation. The two pathways have established avenues of communication to control their activity and determine the fate of stressed cells in a context-dependent manner. The functional interplay between the ISR and mTOR may have significant ramifications in the development and treatment of human diseases such as diabetes, neurodegeneration and cancer.     

Probing disorders of the nervous system using reprogramming approaches

The groundbreaking technologies of induced pluripotency and lineage conversion have generated a genuine opportunity to address fundamental aspects of the diseases that affect the nervous system. These approaches have granted us unrestricted access to the brain and spinal cord of patients and have allowed for the study of disease in the context of human cells, expressing physiological levels of proteins and under each patient's unique genetic constellation. Along with this unprecedented opportunity have come significant challenges, particularly in relation to patient variability, experimental design and data interpretation. Nevertheless, significant progress has been achieved over the past few years both in our ability to create the various neural subtypes that comprise the nervous system and in our efforts to develop cellular models of disease that recapitulate clinical findings identified in patients. In this Review, we present tables listing the various human neural cell types that can be generated and the neurological disease modeling studies that have been reported, describe the current state of the field, highlight important breakthroughs and discuss the next steps and future challenges.     

Effect of natural exogenous antioxidants on aging and on neurodegenerative diseases

Abstract

Aging and neurodegenerative diseases share oxidative stress cell damage and depletion of endogenous antioxidants as mechanisms of injury, phenomena that are occurring at different rates in each process. Nevertheless, as the central nervous system (CNS) consists largely of lipids and has a poor catalase activity, a low amount of superoxide dismutase and is rich in iron, its cellular components are damaged easily by overproduction of free radicals in any of these physiological or pathological conditions. Thus, antioxidants are needed to prevent the formation and to oppose the free radicals damage to DNA, lipids, proteins, and other biomolecules. Due to endogenous antioxidant defenses are inadequate to prevent damage completely, different efforts have been undertaken in order to increase the use of natural antioxidants and to develop antioxidants that might ameliorate neural injury by oxidative stress. In this context, natural antioxidants like flavonoids (quercetin, curcumin, luteolin and catechins), magnolol and honokiol are showing to be the efficient inhibitors of the oxidative process and seem to be a better therapeutic option than the traditional ones (vitamins C and E, and β-carotene) in various models of aging and injury in vitro and in vivo conditions. Thus, the goal of the present review is to discuss the molecular basis, mechanisms of action, functions, and targets of flavonoids, magnolol, honokiol and traditional antioxidants with the aim of obtaining better results when they are prescribed on aging and neurodegenerative diseases.     

Multifunctional liposomes for nasal delivery of the anti-Alzheimer drug tacrine hydrochloride

The purpose of this study was the development of multifunctional liposomes for nasal administration of tacrine hydrochloride. Liposomes were prepared using traditional excipients (cholesterol and phosphatidylcholine), partly enriched with α-tocopherol and/or Omega3 fatty acids. This approach was chosen in order to obtain at the same time two positive results: an enhanced drug permeation through nasal mucosa and a concomitant neuroprotective effect. Several liposome formulations were prepared using the Reverse Phase Evaporation technique followed by membrane filter extrusion. In particular, liposome capacity to enhance drug permeation was evaluated by means of membrane permeation and cellular uptake studies. Furthermore, liposome effect on neuronal viability and intracellular ROS production was evaluated as well as their cytoprotective effect against oxidative stress. All liposome formulations showed a mean diameter in the range of 175?nm to 219?nm with polydispersity index lower than 0.22, a lightly negative zeta potential and excellent encapsulation efficiency. Moreover, along with good mucoadhesive properties, multifunctional liposomes showed a markedly increase in tacrine permeability, which can be related to liposome fusion with cellular membrane, a hypothesis, which was also supported by cellular uptake studies. Finally, the addition of α-tocopherol without Omega3 fatty acids, was found to increase the neuroprotective activity and antioxidant properties of liposomes.     

Response of muscle-based biochemical condition indices to short-term variations in food availability in post-flexion reared sea bass Dicentrarchus labrax (L.) larvae

Six condition indices based on RNA, total soluble protein and two metabolic enzymes [lactate dehydrogenase (LDH) and citrate synthase (CS)] were analysed in muscle tissue of individual larvae, post-flexion reared sea bass Dicentrarchus labrax using DNA and total soluble protein as standards for size. In addition, the effect of 2 days of food deprivation on the cell proliferation rates was assessed. The RNA:DNA best reflected short-term changes in feeding conditions. If standardized by DNA content, LDH activity was a better indicator of condition than any other index but RNA:DNA. Further, the analysis of cell proliferation rates in muscle from 26 day-old larvae proved useful in distinguishing continuously fed larvae from individuals subjected to 2 days of fast.     

Anti-phospholipase C antibodies inhibit the lectin-induced proliferation of human lymphocytes

A novel approach was used to assess the role of phosphoinositide hydrolysis in the mitogenic action of phytohemagglutinin (PHA) or concanavalin A (ConA). The treatment of human peripheral blood leukocytes (PBL) with monospecific antibodies against phospholipase C (PLC) produced a dose-dependent inhibition (up to 100%) of PHA (10 g/ml) or ConA (25 g/ml) proliferative effects. Thus, the activation of membrane-bound PLC is asine-qua-non condition for lectin-induced proliferation of T lymphocytes. The key-role of PLC versus protein kinase C (PKC) is stressed by the fact that the inhibition of PKC with Hidaka's compound H-7 (40 M) produced only a partial blockade (about 25%) of lectin mitogenic effect.To whom correspondence should be addressed.     

Viral p21 Ki-RAS protein: a potent intracellular mitogen that stimulates adenylate cyclase activity in early G1 phase of cultured rat cells

Rat kidney (NRK) cells infected with a temperature-sensitive mutant of the Kirsten sarcoma virus were arrested in the G0/G1 phase of their cell cycle by incubation in serum-deficient medium at a p21-inactivating temperature of 41 degrees C. These quiescent ts K-NRK cells were then stimulated to transit G1 and initiate DNA replication by lowering the temperature to 36 degrees C, which rapidly reactivated p21. Reactivating the viral Ki-RAS protein by temperature shift led to an increase in adenylate cyclase activity in early G1 phase. The Ki-RAS protein increased the sensitivity of adenylate cyclase to guanyl nucleotides by a mechanism that seemed to involve inactivation of the enzyme's inhibitory G1 regulatory protein.