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In this study, extracts from non-psychoactive Cannabis sativa L. varieties were characterized by means of ultra high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS) and their antiproliferative activity was assessed in vitro. The human chronic myelogenous leukaemia cell line K562 was chosen to investigate the mechanism of cell death. The effect on the cell cycle and cell death was analysed by flow cytometry. Proteins related to apoptosis were studied by western blotting. Mechanical properties of cells were assessed using the Micropipette Aspiration Technique (MAT). The results indicated that the cannabidiol (CBD)-rich extract inhibited cell proliferation of K562 cell line in a dose-dependent manner and induced apoptosis via caspase 3 and 7 activation. A significant decrease in the mitochondrial membrane potential was detected, together with the release of cytochrome c into the cytosol. The main apoptotic markers were not involved in the mechanism of cell death. The extract was also able to modify the mechanical properties of cells. Thus, this hemp extract and its pure component CBD deserve further investigation for a possible application against myeloproliferative diseases, also in association with other anticancer drugs.

Mechanobiology has nowadays acquired the status of a topic of fundamental importance in a degree in Biological Sciences. It is inherently a multidisciplinary topic where biology, physics and engineering competences are required. A course in mechanobiology should include lab experiences where students can appreciate how mechanical stimuli from outside affect living cell behaviour. Here we describe all the steps to build a cell stretcher inside an on-stage cell incubator. This device allows exposing living cells to a periodic mechanical stimulus similar to what happens in physiological conditions such as, for example, in the vascular system or in the lungs. The reaction of the cells to the periodic mechanical stretching represents a prototype of a mechanobiological signal integrated by living cells. We also provide the theoretical and experimental aspects related to the calibration of the stretcher apparatus at a level accessible to researchers not used to dealing with topics like continuum mechanics and analysis of deformations. We tested our device by stretching cells of two different lines, U87-MG and Balb-3T3 cells, and we analysed and discussed the effect of the periodic stimulus on both cell reorientation and migration. We also discuss the basic aspects related to the quantitative analysis of the reorientation process and of cell migration. We think that the device we propose can be easily reproduced at low-cost within a project-oriented course in the fields of biology, biotechnology and medical engineering.

In the last few years, several efforts have been made to identify original strategies against glioblastoma multiforme (GBM): this requires a more detailed investigation of the molecular mechanism of GBM so that novel targets can be identified for new possible therapeutic agents. Here, using a combined biochemical and proteomic approach, we evaluated the ability of a blood–brain barrier-permeable 2,3-benzodiazepin-4-one, called 1g, to interfere with the activity and the expression of brain glycogen phosphorylase (PYGB) on U87MG cell line in parallel with the capability of this compound to inhibit the cell growth and cycle. Thus, our results highlighted PYGB as a potential therapeutic target in GBM prompting 1g as a capable anticancer drug thanks to its ability to negatively modulate the uptake and metabolism of glucose, the so-called “Warburg effect”, whose increase is considered a common feature of cancer cells in respect of their normal counterparts.

The edible insect food chain represents a relatively novel food-producing system; hence, associated biological risks still need to be exhaustively evaluated. In the present study, the dynamics of Escherichia coli during the whole living period of Tenebrio molitor larvae (from eggs to pupae) were studied. To this end, a rearing substrate consisting of organic wheat middlings was spiked with E. coli cells at two initial contamination levels: 1 log cfu g

The present research reports the results of a long-term study (70 days) of the dynamics of Staphylococcus aureus artificially inoculated in a Tenebrio molitor rearing chain for human consumption. To this end, a rearing substrate consisting of organic wheat middlings was spiked with S. aureus to obtain three initial contamination levels, namely 1 (low level), 5 (medium level) and 7 (high level) Log colony forming unit per gram. Microbial viable counting coupled with metataxonomic analysis were performed to evaluate: i) the persistence and growth of S. aureus in the rearing substrate; ii) the colonization and growth of S. aureus in the insect larvae; iii) the occurrence and load of S. aureus in the frass (excrement from larvae mixed with substrate residues); iv) the presence of S. aureus enterotoxins in the rearing substrate, frass, and larvae. The results of the present study highlighted that wheat middlings contaminated with S. aureus do not represent a suitable environment for the multiplication of the pathogen, irrespective of the initial contamination level. Of note, frass originated from the larvae reared on contaminated wheat middlings might potentially represent a source of S. aureus, with cell loads depending on the initial contamination level. A complex resident microbiota was revealed by metataxonomic analysis. Interestingly, co-occurrence/co-exclusions analysis did not reveal associations between the target microorganism and the microbiota of wheat middlings, larvae, or frass. Considering safety aspects of larvae, the results overall collected suggested that, under the applied conditions, T. molitor represents an inhospitable or even hostile environment for S. aureus, with this latter showing counts below the detection limit in the larvae at the end of the 70-day rearing trial, irrespective of the initial contamination level. The results also suggested that a combination of bactericidal factors, including unfavorable environmental conditions (such as low a

In recent years, the more widespread availability of biological drugs with specific mechanisms of action has led to significant breakthroughs in the management of severe asthma. Over time, numerous randomised clinical trials have been conducted to evaluate the efficacy and safety of these biologics and define the eligibility criteria of patients suitable for various therapeutic options. These studies were conducted under controlled conditions not always applicable to real life. For this and other reasons, real-world evidence and pragmatic studies are required to provide useful information on the effectiveness of biological drugs and their safety, even in the long term. Because differences in outcomes have sometimes emerged between clinical trials and real-life studies, it is important to clarify the causes of these discrepancies and define the significance of the results of studies conducted in the course of daily clinical practice. Thus, a scientific debate is ongoing, and no consensus has been reached. The purpose of this narrative review is to analyse the differences between randomised trials and real-world evidence studies, focusing on their roles in guiding clinicians among different therapeutic options and understanding the reasons for the large discrepancies often found in the results obtained.

Coronavirus Disease 2019 (COVID-19) is upsetting the world and innovative therapeutic solutions are needed in an attempt to counter this new pandemic. Great hope lies in vaccines, but drugs to cure the infected patient are just as necessary. In the most severe forms of the disease, a cytokine storm with neuroinflammation occurs, putting the patient's life at serious risk, with sometimes long-lasting sequelae. Palmitoylethanolamide (PEA) is known to possess anti-inflammatory and neuroprotective properties, which make it an ideal candidate to be assumed in the earliest stage of the disease. Here, we provide a mini-review on the topic, pointing out phospholipids consumption in COVID-19, the possible development of an antiphospholipid syndrome secondary to SARS-CoV-2 infection, and reporting our preliminary single-case experience concerning to a 45-year-old COVID-19 female patient recently treated with success by micronized / ultramicronized PEA.

On March 11, 2020, the World Health Organization declared coronavirus disease 2019 (COVID-19) a pandemic; from that date, the vaccine race has begun, and many technology platforms to develop a specific and effective COVID-19 vaccine have been launched in several clinical trials (protein subunit, RNA-based, DNA-based, replicating viral vector, nonreplicating viral vector, inactivated virus, live attenuated virus, and virus-like particle). Among the next-generation strategies, nucleoside-modified messenger RNA vaccines appear the most attractive, not only to counteract emerging pathogens but also for the possible applications in regenerative medicine and cancer therapy. However, exactly as all innovative drugs, they deserve careful pharmacovigilance in the short and long term.

Background Coronavirus disease 2019 (COVID-19) is a complex disease with many clinicopathological aspects, including abnormal immunothrombosis, and the full comprehension of its pathogenetic mechanisms is urgently required. Methods/Results By means of a multidisciplinary approach, we here report a catastrophic COVID-19 in a 44-year-old Philippine male patient, discovered lupus anticoagulant (LAC)-positive shortly before death, occurred 8 days after hospitalization in a clinical scenario refractory to standard high acuity care recalling Asherson’s syndrome (catastrophic antiphospholipid syndrome). Conclusion A parallelism between this severe form of COVID-19 and Asherson’s syndrome can be so drawn. Both the diseases in fact exhibit hypercytokinemia, thrombotic microangiopathy, disseminated intravascular coagulation and multiple organ failure, they show a relationship with viral infections, and they are burdened by a high mortality rate. A genetic predisposition to develop these two overlapping conditions may be supposed.

International audience; A novel 2,3-benzodiazepine-4 derivative, named 1g, has recently been shown to function as an anti-proliferative compound. We now show that it perturbs the formation of a functional mitotic spindle, inducing a spindle assembly checkpoint (SAC)-dependent arrest in human cells. Live analysis of individual microtubules indicates that 1g promotes a rapid and reversible reduction in microtubule growth. Unlike most anti-mitotic compounds, we found that 1g does not interfere directly with tubulin or perturb microtubule assembly in vitro The observation that 1g also triggers a SAC-dependent mitotic delay associated with chromosome segregation in Drosophila neural stem cells, suggests that it targets a conserved microtubule regulation module in humans and flies. Altogether, our results indicate that 1g is a novel promising anti-mitotic drug with the unique properties of altering microtubule growth and mitotic spindle organization.

Hermetia illucens larvae are among the most promising insects for use as food or feed ingredients due to their ability to convert organic waste into biomass with high-quality proteins. In this novel food or feed source, the absence of antibiotic-resistant bacteria and their antibiotic resistance (AR) genes, which could be horizontally transferred to animal or human pathogens through the food chain, must be guaranteed. This study was conducted to enhance the extremely scarce knowledge on the occurrence of AR genes conferring resistance to the main classes of antibiotics in a rearing chain of H. illucens larvae and how they were affected by rearing substrates based on coffee silverskin supplemented with increasing percentages of Schizochytrium limacinum or Isochrysis galbana microalgae. Overall, the PCR and nested PCR assays showed a high prevalence of tetracycline resistance genes. No significant effect of rearing substrates on the distribution of the AR genes in the H. illucens larvae was observed. In contrast, the frass samples were characterized by a significant accumulation of AR genes, and this phenomenon was particularly evident for the samples collected after rearing H. illucens larvae on substrates supplemented with high percentages (&gt, 20%) of I. galbana. The latter finding indicates potential safety concerns in reusing frass in agriculture.

Glioblastoma multiforme (GBM) is the most aggressive malignant tumor of the central nervous system, with poor survival in both treated and untreated patients. Recent studies began to explain the molecular pathway, comprising the dynamic structural and mechanical changes involved in GBM. In this context, some studies showed that the human glioblastoma cells release high levels of glutamate, which regulates the proliferation and survival of neuronal progenitor cells. Considering that cancer cells possess properties in common with neural progenitor cells, it is likely that the functions of glutamate receptors may affect the growth of cancer cells and, therefore, open the road to new and more targeted therapies.

Benzodiazepines of natural origin (NBZDs) have been found in human blood and brains as well as in medicinal plants and foods. In plasma and brain tissue there are i.e. diazepam and nordiazepam equal to commercial drugs but there are also other benzodiazepine-like compounds termed "endozepines", which act as agonists at the benzodiazepine receptors of central type (CBR). A synthetic pathway for the production of NBZDs has not yet been found, but it has been suggested that micro-organisms may synthesize molecules with benzodiazepine-like structures. Hence NBZDs could be of both endogenous and exogenous source and be considered as natural anxyolitic and sedative. Interestingly there are also natural compounds, such as the polypeptide Diazepam Binding Inhibitor (DBI) acting as an "inversive agonist" implicated in fair and panic disorders. It has been suggested that NBZDs may play a role in the pathogenesis of hepatic encephalopathy (HE). Multidirectional studies evaluated NBZDs levels (1) in the blood of normal subjects, of cirrhotic with or without HE and in commercial benzodiazepine consumers; (2) in the blood of cirrhotic treated or not with a non-absorbable antibiotic; (3) in several constituents of our diet. In conclusion, NBZDs increase sometime in cirrhotics with or without HE but they reach concentrations not higher than those found in commercial benzodiazepines consumers. Hence NBZDs must be considered as occasional precipitating factor of HE and benzodiazepine antagonists only symptomatic drugs. The finding that NBZDs may be in part synthesized by intestinal bacterial flora and in part constituent of our diet underlines the importance to feed cirrhotic patients with selected food.

PBR is involved in numerous biological functions, including steroid biosynthesis, mitochondrial oxidative phosphorylation and cell proliferation. The presence of PBR at the perinuclear/nuclear subcellular level has been demonstrated in aggressive breast cancer cell lines and human glioma cells where it seems to be involved in cell proliferation. In our study we investigated the presence of perinuclear/nuclear PBR in different hepatic tumor cell lines with regard to binding to [3H] PK 11195 and protein analysis. The results obtained by saturation binding experiments and scatchard analysis of perinuclear/nuclear PBR density in parallel with the results on the growth curves of the cell lines tested, indicate that the perinuclear/nuclear PBR density correlates inversely with cell doubling time. Moreover, the cell line with high perinuclear/nuclear PBR proliferated in response to PBR ligand, whereas that with low perinuclear/nuclear PBR did not. Our results reinforce the idea that the subcellular localisation of PBR defines its function and that this receptor could be a possible target for new strategies against cancer.

Cholesterol is used by cells for biosynthetic processes and for steroid synthesis. Although the role of cholesterol in tumorigenesis is not clear it is known that steroids are important factors in human carcinogenesis. A polypeptide, diazepam binding inhibitor (DBI), which is an endogenous ligand for peripheral benzodiazepine receptors enhances steroidigenesis by promoting cholesterol delivery to the inner mitochondrial membrane which represents the rate-limiting step of steroid biosynthesis. We have assayed the total cholesterol (TC) and the DBI plasma concentrations in patients with liver cirrhosis complicated by hepatocellular carcinoma (HCC) in comparison with those of uncomplicated liver cirrhosis. TC and DBI levels have been studied in 73 cirrhotic patients and in 23 patients with HCC. Both TC and DBI levels were higher in HCC patients when compared with age, sex and Child-Pugh class matched cirrhotic controls. The values (mean+/-S.D.) in patients in Child-Pugh class B and C with and without HCC were respectively 128+/-30 mg/dl vs. 106+/-27 mg/dl (P < 0.01) and 2.05+/-0.78 pmol/ml vs. 0.78+/-0.84 pmol/ml (P < 0.0001). The data may be the result of the metabolic influence of tumors that enhances steroid biosynthesis during tumor proliferation.

Aims The aim of this study is to investigate the effect of hemin in colonic epithelial cells (Caco-2) cell proliferation and if this effect was due to a direct modulation of 18-kDa translocator protein (TSPO) and/or heme oxygenase type 1 (HO-1). Main methods The main methods are as follow: cell proliferation and cell cytotoxic assays on Caco-2 cell lines treated with hemin in the presence or not of 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide (PK 11195) and Sn-protoporphyrin IX (Sn-PPIX), and immunoblotting for TSPO and HO-1 protein analysis, siRNA directed against TSPO. Key findings Hemin was shown to be toxic for the Caco-2 cell line in a concentration and time dependent manner. Although hemin was able to induce HO-1 in a dose dependent manner, a specific HO-1 inhibitor, Sn-PPIX, was unable to interfere with the effect of hemin on Caco-2 cells. Instead, PK 11195, a specific TSPO ligand, was able to counteract the effect of hemin, suggesting an important role of TSPO in the hemin activity. Cell viability assay further confirms the high cytotoxic effects exerted by hemin on Caco-2 cells expressing TSPO compared to the siRNA-TSPO targeted cells. In addition, hemin was able to decrease significantly the TSPO protein density in a dose dependent manner after 24 h of incubation. Significance The interaction and the consecutive down regulation of TSPO by hemin played an important role in the control of Caco-2 cell viability. The presented data suggest that TSPO might contribute to protect cells from potential toxic compounds such as free tetrapyrroles, candidating this receptor as a survival receptor protein.

The bis (1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)-decandioate called IAC, is a new non-peptidyl low molecular weight radical scavenger able to give a fast reaction with the majority of radical species involved in the oxidative stress. This intrinsic property might be of particular interest in all the processes where it presents an over production of reactive oxygen/nitrogen species (ROS/RNS) such as inflammation. Indeed, it is well known that systemic inflammatory response is associated with the production of ROS, nitric oxide (NO), which in turn deplete the endogenous GSH, mediating cytotoxicity. It has been shown that IAC through its antioxidant activity, exerted a protective effect in vitro in islets isolated from type-2 diabetic patients, and in vivo in a non-obese diabetic mouse model and in DNBS-induced colitis in rats. The ability of IAC to protect brain from ischemia, suggests a possible use of the compound in broad range of inflammatory-related diseases. It is well known that the use of non steroidal anti-inflammatory drugs (NSAIDs) is associated with a broad spectrum of untoward side-effects such as gastrointestinal ulceration. The major pathogenetic element in the development of these effects is the depletion of prostaglandins (PGs) through inhibition of cyclooxygenase. The evidence that IAC protects gastric mucosa in an animal model of indomethacin-induced ulcer, through local increase of PGE 2 levels and antioxidant activity, candidates this compound as a novel, promising, anti-inflammatory compound avoiding the major common untoward side-effects elicited by NSAID's.

The peripheral benzodiazepine receptor (PBR), is an 18 kDa protein of the mammalian mitochondrial membrane and is a highly conserved protein among the mammalian. PBR is involved in numerous biological functions, including steroid biosynthesis, mitochondrial oxidative phosporylation and cell proliferation. The presence of PBR at the nuclear subcellular level has been demonstrated in aggressive breast cancer cell line and human glioma cells, where it seems to be involved in cell proliferation. In our previous studies we investigated the presence of nuclear PBR in different hepatic tumour cell lines with regard to binding to [3H] PK 11,195 and protein analysis. The results obtained by saturation binding experiments and Scatchard analysis of nuclear PBR density in parallel with the results on the growth curves of the cell lines tested, indicate that the nuclear PBR density correlates inversely with cell doubling time. Moreover, the cell line with high nuclear PBR proliferates in response to PBR ligands, whereas that with low nuclear PBR does not. All these findings support the idea that PBR could play a pivotal role in cell proliferation and this receptor protein could be potentially important either in early diagnosis or chemopreventive strategies against degenerative disease.

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome, which develops in patients with acute or chronic liver failure. It is widely accepted to be due to impairment of hepatic clearance of toxic products from the gut such as ammonia. Accumulation of ammonia induces a glutamate neurotoxicity leading to an increased tone of the γ-aminobutyric acid A (GABA-A) receptor system in the brain which results in HE. Factors either increasing the ammonia levels (protein load, constipation, sepsis, or gastrointestinal bleeding) or potentiating the functional activity of the GABAergic system [natural benzodiazepine-like compounds (NBZDs) or exogenous benzodiazepines] may act as precipitating factors of HE. NBZDs are present in trace amounts in the blood of normal subjects and have been found to be increased in the blood of patients with liver cirrhosis, with or without HE. These compounds may derive either from the diet since they have been found in plants, vegetables and animals or from gut bacteria. The observation that intestinal bacterial flora is involved in the production of both primary agent of HE (ammonia) and precipitating factors (NBZDs) suggests that the use of nonabsorbable antibiotics such as rifaximin may be useful in preventing episodes of HE in patients with liver cirrhosis.

Summary Stupor is a condition from which the subject can be aroused only by vigorous stimuli. Most patients with stupor have a diffuse organic cerebral dysfunction. Rarely stupor is recurrent and no specific causes can be found. Patients with idiopathic recurrent stupor were awakened by i.v. administration of an antagonist (flumazenil) of the benzodiazepine recognition site located in the GABA A receptor. Since no exogenous benzodiazepines were detected in plasma and cerebrospinal fluid by high performance liquid chromatography, an excess of endogenous benzodiazepine-like compounds (endozepines) was proposed as the cause of stupor. The existence of endozepines, their widespread distribution in the CNS and their involvement in hepatic encephalopathy are established. However, the origin of these compounds, how biosynthesis occurs and the mechanisms and causes through which they alter brain functions are poorly understood. The fact that a number of synthetic benzodiazepines are difficult to detect using conventional techniques and the discovery that some cases of recurrent stupor were caused by fraudulent administration of lorazepam question whether the concept of endozepine recurrent stupor can be sustained. This review summarizes the state of endozepine physiology and pharmacology and the clinical syndromes attributed to their involvement. A diagnostic work-up to define endozepine-induced recurrent stupor is suggested.

As an approach to understanding the role of the alpha1 subunit of the GABA(A) receptor, ribozymes were designed to reduce expression of this subunit protein by hydrolysis of alpha1 subunit message and antisense inactivation. The ribozyme cleavage sites were selected through homology comparison of all known murine GABA(A) receptor subunits at the amino acid and nucleotide sequence level. Two ribozymes were designed and synthesized: one against the extracellular domain and the other against the cytoplasmic domain. These ribozymes were cloned in a mammalian expression plasmid, pZeoSV2 (+). Cleavage of both extracellular and cytoplasmic domain transcripts by the respective ribozymes was observed when each ribozyme was tested against in vitro transcribed mRNA. The stable cell line, 122, expressing recombinant human GABA(A) alpha1, beta2 and gamma2S subunits of receptor was stably transfected with the cytoplasmic domain ribozyme (cy) alone and with both the cytoplasmic (cy) and extracellular domain (ex) ribozyme expression plasmids. Northern analysis showed a 55-60% reduction of alpha1 mRNA in clones of cells transfected with either the single ribozyme (Cy) or with both ribozymes (EC). The alpha1 protein level was reduced 75% in a stable Cy clone and more than 90% in a stable EC clone when compared with alpha1 expression in 122 cells and the vector transfected (Zeo) cells. Electrophysiological analysis revealed that the GABA(A) receptor properties were very similar in 122 cells and in stable clones in which the subunit protein expression had been greatly reduced. No significant difference was detected in the potentiation of the receptor response by either bretazenil or zolpidem. These data demonstrate the efficacy of the ribozyme approach in dramatically reducing GABA(A) subunit protein levels in transfected cells and identify those elements that will be important to the application of similar ribozymes to knock-down transmitter receptor subunit proteins under inducible promoters in transgenic mice.

Ammonia and endogenous benzodiazepines (BDZs) are two of the most important agents among those taken into consideration in the pathogenesis of hepatic encephalopathy (HE).Venous ammonia and endogenous BDZs sera levels were assayed in 58 liver cirrhosis patients (34 male, 24 female) free of commercial BDZs. Endogenous BDZs were measured by binding assay after high-performance liquid chromatography purification. Ammonia was assessed by colorimetric test.Endogenous BDZs and ammonia were significantly higher in Child-Pugh class C than in class B and class A (P0.05), correlating to the severity of the liver dysfunction but not with the degree of HE. A significant difference, in fact, was noted between degree 0 (no HE) versus III-IV of HE (P0.05), but not between degrees I-II versus III-IV. Regression analysis performed to find a correlation between the ammonia and BDZ levels in HE resulted negative.Clinical evidence is provided in cirrhotic patients that ammonia and endogenous BDZ levels do not correlate with each other in the outcome of HE.

The peripheral benzodiazepine receptor system triggers intracellular metabolic events and has been associated with cell proliferation. Its endogenous ligand, the diazepam binding inhibitor, contributes to steroidogenesis by promoting cholesterol delivery to the inner mitochondrial membrane. The present study was undertaken to verify whether this system is altered in tumors sited in the liver. Peripheral benzodiazepine receptors and diazepam binding inhibitor were studied using immunocytochemistry and in situ hybridization in 9 human tumors sited in the liver, in liver hyperplasia, cirrhotic nodular regeneration, intestinal adenocarcinoma and in surrounding non-tumoral tissue. Immunocytochemical staining and in situ hybridization demonstrated that peripheral benzodiazepine receptors and diazepam binding inhibitor were more prominently expressed in neoplastic cells than in non-tumoral tissue. They were present in the same cells, suggesting that diazepam binding inhibitor may act in an intracrine manner in these cells. Higher peripheral benzodiazepine receptors and diazepam binding inhibitor expression in tumor cells suggest an implication of this system in the metabolism of neoplastic cells. Furthermore the evaluation of peripheral benzodiazepine receptor and diazepam binding inhibitor expression might be useful in evaluating malignancy and in diagnostic approaches of tumors in liver tissue.

Increased number of peripheral benzodiazepine receptors (PBRs) have been found in some tumors outside the liver. The present study was to verify whether the PBR system is altered in hepatocellular carcinoma (HCC). The levels of endogenous benzodiazepine-like compounds (BZDs). measured by radioreceptor binding technique after HPLC purification and the endogenous ligand for PBRs. termed diazepam binding inhibitor (DBI). measured by radioimmunoassay utilizing a specific antibody for human DBI, were studied in the blood of 15 normal subjects, 12 liver cirrhosis and 10 patients with HCC. The levels of BZDs in serum were increased hundred fold in liver cirrhosis patients and slightly elevated in HCC patients. DBI was found to be increased in HCC patients. The binding recognition sites for PBRs (Bmax) were increased 4 to 7 fold in HCC tissue in comparison with that found in non-tumoral liver tissue (NTLT). On the contrary the concentrations of DBI were found to be significantly decreased in HCC tissue in comparison with the respective NTLT. These results seem to suggest an implication of PBRs and of their putative endogenous ligands in the metabolism of these neoplastic cells and possibly in their proliferation. The up-regulation of PBRs found in HCC tissue seems to indicate an increased functional activity of these receptors and opens up the possibility of new pharmacological and diagnostic approaches while the changes in the circulating endogenous ligands for the above receptors might be envisaged as early markers of tumorigenesis in liver cirrhosis.

1. We investigated La3+ effects on recombinant and native gamma-aminobutyric acid A (GABAA) receptors using rapid agonist applications and on inhibitory synaptic currents (IPSCs) in granule and stellate neurons of rat cerebellar slices. 2. Rapid desensitization of currents elicited by 200 ms pulses of 1 mM GABA to small lifted cells transfected with alpha1beta3gamma2 cDNAs was greatly decreased by the coapplication of 100 microM LaCl3. 3. GABA responses were unaffected when coapplication lasted only 2 ms. In contrast, with LaCl3 pre-perfusion, a significant slowing of deactivation in response to 2 ms applications was observed. LaCl3 pre-perfusion also prolonged the duration of responses to 20 mM taurine. 4. Outside-out patches excised from cells transfected with alpha1beta3gamma2 subunit cDNAs were briefly exposed to a saturating concentration of GABA, eliciting a transient activation of single channel currents with a main conductance of 30 pS. Opening and burst durations increased by pre-equilibration of patches with LaCl3. 5. LaCl3 depressed the peak amplitude without affecting the slow deactivation and desensitization of GABA responses in cells transfected with alpha6beta3gamma2 and alpha6beta3delta cDNAs. No significant difference in La3+ modulation of GABA-gated currents was observed between alpha1beta3gamma2 and alpha1beta3delta receptors. 6. The effects of LaCl3 on deactivation and desensitization of GABA responses observed in nucleated patches excised from rat cerebellar granule and stellate neurons were comparable to those in the cells transfected with alpha1beta3gamma2 cDNAs. In addition, La3+ clearly prolonged the spontaneous IPSC time course without changing the amplitude. 7. Our results indicate that La3+ has a dual action on GABA-gated currents: it decreases desensitization and increases channel opening duration. These actions depend on receptor subunit composition and contribute to the prolongation of IPSCs.

Benzodiazepine-like compounds have been implicated in the pathogenesis of encephalopathy after fulminant hepatic failure.The levels and the nature of benzodiazepine-like compounds were determined in six cases of fulminant hepatic failure during the course of the disease. Blood samples were collected on admission and a few days later, when the neurologic status had improved in five cases and immediately before death in one case. The compounds were measured in sera with a binding technique after high-performance liquid chromatography purification and analyzed with mass spectrometry.Their levels were highly variable in those with severe encephalopathy and were still increased on awakening in some cases. Diazepam and N-desmethyldiazepam were inconsistently present.The inconsistent presence of benzodiazepine-like compounds in encephalopathy after fulminant hepatic failure and their persistence, in some cases, at high levels on awakening from coma seem to indicate that the encephalopathy is not strictly dependent on the levels of these compounds.