Active immunotherapy against pathogenic Cis pT231-tau suppresses neurodegeneration in traumatic brain injury mouse models

Traumatic brain injury (TBI), characterized by acute neurological impairment, is associated with a higher incidence of neurodegenerative diseases, particularly chronic traumatic encephalopathy (CTE), Alzheimer's disease (AD), and Parkinson's disease (PD), whose hallmarks include hyperphosphorylated tau protein. Recently, phosphorylated tau at Thr231 has been shown to exist in two distinct cis and trans conformations. Moreover, targeted elimination of cis P-tau by passive immunotherapy with an appropriate mAb that efficiently suppresses tau-mediated neurodegeneration in severe TBI mouse models has proven to be a useful tool to characterize the neurotoxic role of cis P-tau as an early driver of the tauopathy process after TBI. Here, we investigated whether active immunotherapy can develop sufficient neutralizing antibodies to specifically target and eliminate cis P-tau in the brain of TBI mouse models. First, we explored the therapeutic efficacy of two different vaccines. C57BL/6 J mice were immunized with either cis or trans P-tau conformational peptides plus adjuvant. After rmTBI in mice, we found that cis peptide administration developed a specific Ab that precisely targeted and neutralized cis P-tau, inhibited the development of neuropathology and brain dysfunction, and restored various structural and functional sequelae associated with TBI in chronic phases. In contrast, trans P-tau peptide application not only lacked neuroprotective properties, but also contributed to a number of neuropathological features, including progressive TBI-induced neuroinflammation, widespread tau-mediated neurodegeneration, worsening functional deficits, and brain atrophy. Taken together, our results suggest that active immunotherapy strategies against pathogenic cis P-tau can halt the process of tauopathy and would have profound clinical implications.

Stem cell therapy in Alzheimer's disease: possible benefits and limiting drawbacks

Alzheimer's disease (AD) is the sixth leading cause of death globally and the main reason for dementia in elderly people. AD is a long-term and progressive neurodegenerative disorder that steadily worsens memory and communicating skills eventually leads to a disabled person of performing simple daily tasks. Unfortunately, numerous clinical trials exploring new therapeutic drugs have encountered disappointing outcomes in terms of improved cognitive performance since they are not capable of halting or stimulating the regeneration of already-damaged neural cells, and merely provide symptomatic relief. Therefore, a deeper understanding of the mechanism of action of stem cell may contribute to the development of novel and effective therapies. The revolutionary discovery of stem cells has cast a new hope for the development of disease-modifying treatments for AD, in terms of their potency in the replenishment of lost cells via differentiating towards specific lineages, stimulating in situ neurogenesis, and delivering the therapeutic agents to the brain. Herein, firstly, we explore the pathophysiology of AD. Next, we summarize the most recent preclinical stem cell reports designed for AD treatment, their benefits and outcomes according to cell type. We briefly review relevant clinical trials and their potential clinical applications in order to find a unique solution to effectively relieve the patients' pain.

Essentialism and Islamic Theology of Homosexuality: A Critical Reflection on an Essentialist Epistemology toward Same-Sex Desires and Acts in Islam

Although most traditional Muslim scholars condemn same-sex desires and acts, revisionist Muslim scholars have offered a more tolerant approach on this issue over the last two decades. Building on an essentialist approach to same-sex desires and acts, these scholars have argued that Islam accepts difference and diversity, including sexual diversity, as part of God's creation. Homosexuality, which in their view is an innate disposition to the same sex, is an alternative sexuality and, thus, accepted by the Qur'an and Islam. This article argues that an essentialist approach is not suitable to defend all manifestations of same-sex desires and acts, not only because it is narrow (as it excludes both bisexual Muslims and homosexual Muslims who believe that their sexual orientation is socially constructed), but also because it cannot even argue the case for the view of homosexuality as inborn. This article proposes to open up the debate beyond essentialism and constructivism, which both have their limitations, to accommodate a more inclusive and tolerant Islamic approach to same-sex desires and acts.

Effect of sub-chronic intraperitoneal administration of aminoguanidine on the memory and hippocampal apoptosis-related genes in diabetic rats

Memory impairment is a common disorder in diabetes mellitus which is associated with hippocampal neuronal apoptosis. The present study was conducted to examine the effect of one-week intraperitoneal (ip), administration of aminoguanidine (AG) on passive avoidance learning (PAL) and Bcl-2 family gene expression in the hippocampus of rats. Sixty male rats were divided into ten groups: non-diabetic/diabetic animals with/without AG (50, 100, 200 and 400 mg/kg, ip) treatment for one week. PAL and Bcl-2 family genes were examined. AG (100 and 200 mg/kg) improved both memory and Bax, Bak, Bcl-2 and Bcl-xl deficiency significantly in diabetic rats. AG treatment also ameliorated the diabetes-induced changes in (Bcl-2+Bcl-xl)/(Bak+Bax) ratios considerably. These results propose that one-week ip administration of AG may recover the deficit cognition in diabetic rats via enhancing (Bcl-2+Bcl-xl)/(Bak+Bax) proportions (Tab. 2, Fig. 4, Ref. 55).

EFFECTS OF EXERCISE ON MIR-29 AND IGF-1 EXPRESSION AND LIPID PROFILE IN THE HEART OF OVARIECTOMIZED RAT

Introduction

Menopause increases the risk of cardiovascular disease in women. The aims of the present study were to evaluate the effects of swimming training on cardiac histology and expression of miR-29 and IGF-1 in the ovariectomized rats.

Materials and methods

Thirty female Wistar rats were divided into sham and ovariectomized groups: sedentary control (OVX) and trained with 8 weeks exercise (OVX.E). On 57^th day, blood was collected and used for lipid profile measurement. In addition, heart tissue was analyzed by reverse transcription-polymerase chain reaction for IGF-1 mRNA and miR-29, and studied for histopathological changes.

Results

Ovariectomy significantly decreased miR-29 and IGF-1 expression in the heart compared to sham animals group (p<0.05). Exercise training increased miR-29 and IGF-1 expression in the trained rats and improved histology and lipid profile compared with OVX group (p<0.05).

Conclusion

Estrogen deficiency could lead to cardiac fibrosis through deregulation miR-29 and IGF-1 expression. The findings of the current study suggests a protective effect of exercise on heart against fibrotic changes in ovariectomized rats and support a potential preventive value of exercise in improving cardiac function after menopause.

Protective effects of Iranian Achillea wilhelmsii essential oil on acetaminophen-induced oxidative stress in rat liver

CONTEXT

Achillea wilhelmsii C. Koch (Asteraceae) is widely used in Iranian traditional medicine.

OBJECTIVE

This in vivo study evaluates the hepatoprotective role of Iranian A. wilhelmsii oils against acetaminophen-induced oxidative damages in rats.

MATERIALS AND METHODS

The animals were divided into five groups: in negative control and control groups, the DMSO and 500 mg/kg acetaminophen were i.p. injected, respectively. In treatment groups, 100 and 200 mg/kg oils and 10 mg/kg BHT were given i.p. immediately after acetaminophen administration. Then, the hepatic oxidative/antioxidant parameters such as lipid peroxidation (LP), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and ferric reducing ability of plasma (FRAP) were measured in time intervals (2, 4, 8, 16, and 24 h) after administrations confirmed by histophatological consideration at 24 h.

RESULTS

The results indicated that acetaminophen caused a significant elevation in SOD activity (8-24 h) and LP and FRAP levels (4 h) paralleled with significant decline in GSH level (4 and 8 h). The apparent oxidative injury was associated with evident hepatic necrosis confirmed in histological examination. The presences of A. wilhelmsii oils (100 and 200 mg/kg) with acetaminophen mitigated significantly the rise in SOD, LP, and FRAP levels and restored the GSH compared with the group treated with acetaminophen. These were confirmed by histological examination indicating the hepatic necrosis reversal by the oils.

DISCUSSION AND CONCLUSION

It can be concluded that concomitant administration of A. wilhelmsii oils with acetaminophen may be useful in reversing the drug hepatotoxicity.

Co-encapsulation of gallium with gentamicin in liposomes enhances antimicrobial activity of gentamicin against Pseudomonas aeruginosa

OBJECTIVES

The aim of this study was to enhance the antimicrobial efficacy of a liposomal gentamicin formulation with gallium metal (Lipo-Ga-GEN) against clinical isolates of Pseudomonas aeruginosa.

METHODS

Sputum isolates of P. aeruginosa from cystic fibrosis patients were used to determine the MIC and MBC of Lipo-Ga-GEN. P. aeruginosa biofilms were formed and used to compare the minimum biofilm eradication concentration of the conventional drugs with that of Lipo-Ga-GEN. Quorum sensing (QS) molecule reduction of P. aeruginosa was determined by monitoring N-acyl homoserine lactone production using Agrobacterium tumefaciens reporter strain (A136). Viability of the cultured human lung epithelial cells (A549) was determined by Trypan Blue assay in order to assess Ga toxicity.

RESULTS

MIC and MBC values indicated that gentamicin was more effective against a highly resistant strain of P. aeruginosa (PA-48913) when delivered as a Lipo-Ga-GEN formulation (256 mg/L free gentamicin versus 2 mg/L Lipo-Ga-GEN). Lipo-Ga-GEN was the only formulation that completely eradicated biofilms and blocked QS molecules at a very low concentration (0.94 mg/L gentamicin). The decrease in cell viability was less in A549 cells exposed to Lipo-Ga, suggesting that encapsulated Ga is safer.

CONCLUSIONS

The results clearly indicate that the Lipo-Ga-GEN formulation is more effective than gentamicin alone in eradicating antibiotic-resistant P. aeruginosa isolates growing in a planktonic or biofilm community.

The effects of insulin on glucose and fluid transport in the isolated small intestine of normal rats

Chronically administered insulin returns enhanced maximal glucose transport capacity induced by diabetes to its normal state. In this study, the direct and acute effects of insulin on glucose transport in different parts of isolated small intestine were investigated. Mucosal Fluid Transport (MFT), Mucosal Glucose Transport (MGT) and Serosal Glucose Transport (SGT) were measured in the presence and absence of insulin in averted sacs, prepared from female Wistar rats. This study shows that the presence of insulin in vitro (40 and 80 microU/mL) can reduce MGT and SGT in different segments of the small intestine (duodenum, jejunum and ileum) after 30 min whereas it had no effect on MFT. Mucosal glucose transfer rates in the duodenum, jejunum and ileum of the controls were 6.07+/-0.4, 6.34+/-0.62 and 6.43+/-0.47 mg/g tissue respectively which were significantly reduced to 3.82+/-0.93, 3.60+/-0.50 and 1.17+/-0.45 in the presence of 80 microU/mL of insulin. Serosal glucose transfer too was decreased significantly from 0.3+/-0.05, 0.57+/-0.07 and 0.43+/-.07 in the duodenum, jejunum and ileum to 0.16+/-0.03, 0.16+/-0.04 and .07+/-.02 respectively. Mucosal fluid transfer was not affected by insulin. Insulin was as effective whether it was added on the mucosal or the serosal side. The results of this study show that insulin can directly affect glucose transport in the small intestine; its physiological role must be examined. Direct effect of insulin deficiency on glucose absorption in diabetic patients may play a role in the pathophysiology of the disease.

A comparative study on the cortico-hypoglossal connections in primates, using biotin dextranamine

The anterograde projections of the motorcortical tongue area to the hypoglossal nucleus and neighbouring structures were studied in the rhesus monkey, squirrel monkey, saddle-back tamarin and tree shrew. Biotin dextranamine served as tracer. Direct projections into the hypoglossal nucleus were only found in the rhesus monkey and squirrel monkey. All four species, however, showed a direct projection into the dorsal and parvocellular reticular formation which in turn projects into the hypoglossal nucleus. The findings suggest a phylogenetic trend in the projections of the motorcortical tongue area from non-primate mammals via non-human primates to man in the sense that the cortico-motoneuronal connection is strengthened towards man. This might be one reason for the superior role the tongue plays in human vocal behaviour in contrast to non-human vocalization.

Anterograde projections of the cortical tongue area of the tree shrew (Tupaia belangeri)

In altogether seven tree shrews, Tupaia belangeri, the anterograde projections of the motorcortical tongue area were investigated as part of a larger comparative study. Identification of the tongue area was carried out by electrical brain stimulation. Three different tracers were used: biotin-conjugated dextranamine (BDA), Phaseolus vulgaris leucoagglutinin (PHA-L) and 3H-leucine. Intracortical projections were found to the motor cortex around the injection site, the premotor cortex, supplementary motor area, the homologues of the primate frontoparietal operculum and insula, the anterior cingulate and agrannular retrosplenial cortex, the somatosensory and bordering inferior parietal cortex as well as to the perirhinal cortex. Except the very weak projections into the retrosplenial, posterior parietal and perirhinal region which were ipsilateral, all other projections were bilateral. Subcortically, there was a projection into the ventral putamen, rostrodorsal claustrum and, very sparsely, into the caudate nucleus. In the thalamus, terminal labeling was found in the nuclei reticularis, anteroventralis, anteromedialis, ventralis lateralis, ventralis posterior medialis, ventralis posterior inferior, medialis dorsalis, in the intralaminar nuclei paracentralis, centralis lateralis, centrum medianum and parafascicularis, in the midline thalamus and in the nuclei posterior and pulvinaris. Further diencephalic projections, however all of them wak, could be traced into the zona incerta, dorsolateral subthalamus, dorsomedial, lateral and supraoptic hypothalamus. In the midbrain, labeling was found in the deep layers of the lateral superior colliculus, in the bordering reticular formation and, very sparsely, in the periaqueductal grey. In the lower brain-stem, fibres ended in the griseum pontis, dorsolateral reticular formation, principal and spinal trigeminal nucleus and, sparsely, in the lateral parabrachial region, solitary tract nucleus, inferior olive and magnocellular reticular formation. No terminals were found in the hypoglossal nucleus. The projection system revealed with PHA-L was less extensive than that demonstrated with BDA and 3H-leucine, both of which were similar.

Human bioassays to assess environmental genotoxicity: development of a DNA break bioassay in HepG2 cells

OBJECTIVES

Increasing interest in environmental health issues has created a demand for improved methods for the assessment of pollutant effects on humans. Our laboratory has developed an in vitro assay for the quantification of genotoxicity, monitored as DNA single strand breaks (SSB), in the HepG2 human hepatoma cell line.

DESIGN AND METHODS

This assay procedure, which is based upon alkaline unwinding and hydroxylapatite DNA chromatography, is both rapid and simple to perform.

RESULTS

HepG2 cells responded to the standard mutagen, 4-nitroquinoline N-oxide, demonstrating SSB formation at concentrations above 0.1 mumol/L. Phenanthrene-9,10-quinone, a component of diesel exhaust, mediated SSB formation at concentrations above 250 nmol/L. Finally, an extract of contaminated sediment from the Great Lakes Basin mediated SSB formation in a dose-dependent manner.

CONCLUSIONS

These results illustrate the utility of this human genotoxicity assay for future use in screening of environmental pollutants.

Right ventricular endomyocardial fibrosis simulating Ebstein's anomaly

A case of right ventricular endomyocardial fibrosis simulating Ebstein's anomaly is described. The clinical features, chest x-ray, electrocardiogram, echocardiogram, intracardiac electrogram, and the angiogram were all compatible with Ebstein's malformation. A correct diagnosis was subsequently made in the operating room. Reasons for the difficulties in the differential diagnoses of these two entities are discussed.