Gastroprotective Effect of Microencapsulated Myrtus communis Essential Oil against Ethanol/HCl-Induced Acute Gastric Lesions

Myrtus communis L. essential oil (EO), mainly composed of myrtenyl acetate (30.6%), linalool (14.9%), α-pinene (11.10%) and 1,8-cineole or eucalyptol (9.9%), was microencapsulated with maltodextrin by emulsification and spray-drying, reaching a yield and efficiency of 43.7 and 48.7%, respectively. The microencapsulated myrtle EO (MMEO) was then evaluated regarding its gastroprotective activity in a model of ethanol/HCl-induced acute gastric ulcer in Wistar rats. Pretreatment with MMEO induced a remarkable inhibition of gastric lesions and acidity, correlated to high healing and protection percentages. Moreover, it exerted a potent anti-inflammatory effect on the gastric mucosa, counteracting EtOH-induced gastric lipoperoxidation and preventing the depletion of the antioxidant enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Taken together, the gastroprotective action of encapsulated MMEO may be multi-factorial, and ascribable, at least in parts, to its anti-inflammatory and antioxidant properties.

[Takayasu's arteritis and atherosclerosis]

INTRODUCTION

Chronic inflammatory diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), are accompanied by high cardiovascular morbidity and mortality secondary to accelerated and premature atherosclerosis. Atherosclerosis is correlated with chronic systemic inflammation independently of the factors for cardiovascular risk. Vasculitis of large arteries such as Takayasu's disease, are characterized both by chronic systemic inflammation and local parietal vascular inflammation.

METHODS

We prospectively analyzed in a case-control study, a group of 64 carriers of Takayasu's arteritis patients with a mean age of 41 years [±11.94], a group of 50 RA female patients aged 45 years [±10.27], and a control group with an average age of 44 years [±12.63]. We recorded classic cardiovascular risk factors and used the Framingham equation to calculate the risk. We measured the intima-media thickness (IMT) in the carotids and noted the presence of carotid, aortic and femoral atheroma.

RESULTS

The mean calculated cardiovascular risk was 3.5 % in the Takayasu's group. It was 4.4 % in the RA group, and 4.5 % in controls with no significant difference between the three groups (P=0.153). Subclinical atherosclerosis defined by IMT> 0.70mm and/or the presence of atheroma plaque was found in 87 % of Takayasu's patients versus 76 % of RA patients, (P=0.088) and 48 % of controls (P<0.001). Most atherosclerotic plaques were found in the Takayasu group. Compared to the control group the carotid intima-media thickness was significantly higher in the Takayasu group. The average IMT in the Takayasu group was 0.91mm [±0.368], 0.76mm [±0.151] for the PR group, and 0.71mm [±0.141] for controls.

DISCUSSION

Atherosclerosis observed in Takayasu's disease was accelerated and premature, occurring in young patients with a low overall cardiovascular risk. Recent data support the central role of inflammation in all stages of atherogenesis from endothelial dysfunction to plaque rupture. Systemic inflammation associated with local parietal inflammation observed in Takayasu's arteritis, appears to be responsible for accelerated and premature atherosclerosis. The results of our study and the literature review favor an active strategy for cardiovascular prevention in Takayasu's disease.

Neuroprotective effect of grape seed extract on brain ischemia: a proteomic approach

Stroke is one of the leading causes of long-lasting disability in human and oxidative stress an important underlying cause. Molecular insights into pathophysiology of ischemic stroke are still obscure, and the present study investigated the protective effect of high dosage Grape Seed Extract (GSE 2.5 g/kg) on brain ischemia-reperfusion (I/R) injury using a proteomic approach. Ischemia was realized by occlusion of the common carotid arteries for 30 min followed by 1 h reperfusion on control or GSE pre-treated rats, and a label-free quantification followed by mass spectrometry analysis used to evaluate I/R induced alterations in protein abundance and metabolic pathways as well as the protection afforded by GSE. I/R-induced whole brain ionogram dyshomeostasis, ultrastructural alterations, as well as inflammation into hippocampal dentate gyrus area, which were evaluated using ICP-OES, transmission electron microscopy and immuno-histochemistry respectively. I/R altered the whole brain proteome abundance among which 108 proteins were significantly modified (35 up and 73 down-regulated proteins). Eighty-four proteins were protected upon GSE treatment among which 27 were up and 57 down-regulated proteins, suggesting a potent protective effect of GSE close to 78%of the disturbed proteome. Furthermore, GSE efficiently prevented the brain from I/R-induced ion dyshomeostasis, ultrastructural alterations, inflammatory biomarkers as CD56 or CD68 and calcium burst within the hippocampus. To conclude, a potent protective effect of GSE on brain ischemia is evidenced and clinical trials using high dosage GSE should be envisaged on people at high risk for stroke.

Antioxidant and Anti-Apoptotic Activity of Octadecaneuropeptide Against 6-OHDA Toxicity in Cultured Rat Astrocytes

Oxidative stress, associated with various neurodegenerative diseases, promotes ROS generation, impairs cellular antioxidant defenses, and finally, triggers both neurons and astroglial cell death by apoptosis. Astrocytes specifically synthesize and release endozepines, a family of regulatory peptides, including the octadecaneuropeptide (ODN). We have previously reported that ODN acts as a potent neuroprotective agent that prevents 6-OHDA-induced apoptotic neuronal death. The purpose of the present study was to investigate the potential glioprotective effect of ODN on 6-OHDA-induced oxidative stress and cell death in cultured rat astrocytes. Incubation of astrocytes with graded concentrations of ODN (10^-14 to 10^-8 M) inhibited 6-OHDA-evoked cell death in a concentration- and time-dependent manner. In addition, ODN prevented the decrease of mitochondrial activity and caspase-3 activation induced by 6-OHDA. 6-OHDA-treated cells also exhibited enhanced levels of ROS associated with a generation of H₂O₂ and O₂^°-, and a reduction of both superoxide dismutase (SOD) and catalase (CAT) activities. Co-treatment of astrocytes with low concentrations of ODN dose-dependently blocked 6-OHDA-evoked production of ROS and inhibition of antioxidant enzyme activities. Concomitantly, ODN stimulated Mn-SOD, CAT, glutathione peroxidase-1, and sulfiredoxin-1 gene transcription and rescued 6-OHDA-associated reduced expression of endogenous antioxidant enzymes. Taken together, these data indicate that, in rat astrocytes, ODN exerts anti-apoptotic and anti-oxidative activities, and hence prevents 6-OHDA-induced oxidative assault and cell death. ODN is thus a potential candidate to delay neuronal damages in various pathological conditions involving oxidative neurodegeneration.

Endogenous Expression of ODN-Related Peptides in Astrocytes Contributes to Cell Protection Against Oxidative Stress: Astrocyte-Neuron Crosstalk Relevance for Neuronal Survival

Astroglial cells are important actors in the defense of brain against oxidative stress injuries. Glial cells synthesize and release the octadecaneuropeptide ODN, a diazepam-binding inhibitor (DBI)-related peptide, which acts through its metabotropic receptor to protect neurons and astrocytes from oxidative stress-induced apoptosis. The purpose of the present study is to examine the contribution of the endogenous ODN in the protection of astrocytes and neurons from moderate oxidative stress. The administration of H₂O₂ (50 μM, 6 h) induced a moderate oxidative stress in cultured astrocytes, i.e., an increase in reactive oxygen species, malondialdehyde, and carbonyl group levels, but it had no effect on astrocyte death. Mass spectrometry and QPCR analysis revealed that 50 μM H₂O₂ increased ODN release and DBI mRNA levels. The inhibition of ODN release or pharmacological blockage of the effects of ODN revealed that in these conditions, 50 μM H₂O₂ induced the death of astrocytes. The transfection of astrocytes with DBI siRNA increased the vulnerability of cells to moderate stress. Finally, the addition of 1 nM ODN to culture media reversed cell death observed in DBI-deficient astrocytes. The treatment of neurons with media from 50 μM H₂O₂-stressed astrocytes significantly reduced the neuronal death induced by H₂O₂; this effect is greatly attenuated by the administration of an ODN metabotropic receptor antagonist. Overall, these results indicate that astrocytes produce authentic ODN, notably in a moderate oxidative stress situation, and this glio- and neuro-protective agent may form part of the brain defense mechanisms against oxidative stress injury.

[Hypertension during Takayasu's disease: An Algerian single center experience of 279 patients]

INTRODUCTION

Takayasu arteritis (TA) is an uncommon large vessel arteritis. Lesions produced by the inflammatory process can be stenotic, occlusive, or aneurysmal. Vascular changes lead to the main complications, including hypertension, most often due to renal artery stenosis or, more rarely, stenosis of the suprarenal aorta.

AIM OF STUDY

Our study will assess the prevalence of hypertension during TA and describe its clinical profile.

MATERIAL AND METHODS

Among 279 patients with TA resulting from single center study over a period of 35 years, we collected 128 hypertensive patients. All have benefited from a vascular exploration. Renal angiography was performed in 85 patients. The classification of Lupi Herrera allowed us to distribute our patients according to the topography of their lesions. Patients are classified according to the degree of severity of their hypertension. Results are statistically analyzed with SPSS 10.0 database.

RESULTS

The prevalence of hypertension is 45.8%, mainly affecting young women (87%). It is indicative of arteritis in 24.7%. Its diagnosis is difficult and delayed when arterial stenosis exist: inter-arm blood pressure difference (53.8%), inverse coarctation (30.4%) or unmeasurable blood pressure at the 4 limbs (6.8%). In 54% of cases, hypertension was due to a renal artery stenosis. The presence of arterial hypertension was associated to a poor prognosis: it was severe in 54% of patients and was linked to 70% of deaths observed.

CONCLUSION

Arterial hypertension is common during TA. It remains a factor of bad prognosis specially when renovascular hypertension is present.

Effect of White Kidney Beans (Phaseolus vulgaris L. var. Beldia) on Small Intestine Morphology and Function in Wistar Rats

The chronic ingestion of raw or undercooked kidney beans (Phaseolus vulgaris L.) causes functional and morphological derangement in various tissues. The major objectives of this study were to investigate the gavage effects of a raw Beldia bean variety that is widely consumed in Tunisia, on the small intestine morphology and jejunal absorption of water, electrolytes, and glucose in Wistar rats. Twenty young male rats were randomly divided into two groups of 10 rats. The first group served as the control and was gavaged with 300 mg of a rodent pellet flour suspension (RPFS), whereas the second experimental group was challenged with 300 mg of a Beldia bean flour suspension (BBFS) for 10 days. Histological studies were performed using light and electron microcopy. The intestinal transport of water, sodium, potassium, and glucose was studied by perfusing the jejunal loops of the small bowels in vivo. The feeding experiments indicated that BBFS did not affect weight gain. Histomorphometric analyses showed that the villus heights, crypt depths, and crypt/villus ratios in the jejunum and ileum were greater in the BBFS-fed rats than controls. Electron microscopy studies demonstrated that the rats exposed to RPFS exhibited intact intestinal tracts; however, the BBFS-treated rats demonstrated intestinal alterations characterized by abnormal microvillus architectures, with short and dense or long and slender features, in addition to the sparse presence of vesicles near the brush border membrane. BBFS administration did not significantly affect glucose absorption. However, significant decreases were observed in water and electrolyte absorption compared with the uptake of the controls. In conclusion, raw Beldia beans distorted jejunum morphology and disturbed hydroelectrolytic flux.

[Kindler syndrome: three cases reports in three siblings]

INTRODUCTION

Kindler syndrome is a rare type of genetic skin condition belonging to the class of bullous poikilodermia. We report three new cases of this rare syndrome.

CASE REPORTS

This condition was seen in two brothers aged 4 and 14 years and in their sister aged 6 years, born of a first-degree consanguineous marriage in a family with Kindler syndrome of varying degrees of severity. The three patients presented spontaneously regressive bullous eruptions, poikilodermia of gradual onset, major cutaneous atrophy on the back of the hands and the feet, pseudo-syndactyly and photosensitivity. The older brother presented a severe form complicated by chronic terminal renal failure with hydronephrosis secondary to urethral stenosis and hypertension as well as oesophageal stenosis requiring dilatation sessions. Electron microscopy examination of poikilodermic skin showed normal anchoring filaments and proliferation of the basal layer. Electron microscopy examination of rubbed poikilodermic skin from the other two siblings showed cleavage at both the superficial and deep intra-epidermal levels.

DISCUSSION

Diagnosis of Kindler syndrome is based upon clinical evidence. Electron microscopic examination is used in particular to rule out congenital bullous epidermolysis. Detachment of layers at two or three different levels in relation to the dermal-epidermal junction described in the literature forms a specific but inconsistent feature of Kindler syndrome.

Michelin tire syndrome: a report of two siblings

Michelin tire syndrome is a rare syndrome characterized by excessive folding of the skin. The diagnosis is mainly clinical. It has been found to be associated with noncutaneous anomalies, and probably reflects multiple underlying disorders. We report two siblings with Michelin tire syndrome, a 5-year-old boy and his sister both of whom had marked skin folds and facial anomalies. Histologic study found an increase in smooth muscle fibers of the dermis. Electron microscopy showed details of smooth muscle cells. We also review reported cases in the literature to contribute to a better understanding of this syndrome.

Chronic iodine overload and apoptosis in cold nodules from endemic multinodular goiters

As apoptosis and necrosis are known to exist during experimental goiter development and involution, we studied them in ten Tunisian multinodular endemic goiters, five of them having received a chronic excess of iodine during six months. Apoptotic thyrocyte nuclei have been counted on hematoxylin-eosin stained semi-thin sections. Using immunoperoxidase on paraffin sections, bcl-2 and bax immunoreactivities have been evidenced, and CD34 positive microvessels counted; ultra-thin sections have also been observed. After six months of iodine overload, apoptotic thyrocytes were ten times more numerous; CD34 positive endothelial cells were diminished by one half bcl-2 immunoreactivity disappeared in thyrocytes and a bax one appeared in thyroid follicular and endothelial cells. Presence of numerous apoptotic follicular and endothelial cells was confirmed using electron microscopy. Chronic iodine excess induces apoptosis and necrosis of thyroid follicular and endothelial cells, leading to thyroglobulin accumulation in connective tissue.

[Vitamin A effects on morphometric adaptation after extensive small bowel resection in the rat]

This work was conceived to study, in the rat short bowel syndrome, the effect of precocious administration of retinoic acid on morphometric adaptation in the remnant intestine. Mitotic index, villous height, crypt depth and mucosal aspect were determined in 2 groups of rats (n=12) after 60% small bowel resection. 100 microg of retinoic acid were perfused immediately after resection in the first group. Control group rats received placebo. Two similar groups (n=12) underwent intestinal transection with or without retinoic acid perfusion. Our results show that retinoic acid induced precocious and significant enhancement of all morphometric parameters when compared to placebo.

IL-18 mRNA expression and IFN-gamma induction in bronchoalveolar lavage from Behçet's disease

OBJECTIVE

IL-18 expression and functional activity has been identified in several autoimmune and infectious diseases. To clarify the potential role of IL-18 during pulmonary Behçet's disease (BD), we have explored the capacity of IL-18 to induce the expression of IFN-gamma.

METHODS

We studied bronchoalveolar lavage (BAL) from 12 patients with BD, 10 patients with silicosis as the control disease and 10 BAL from healthy subjects. BAL fluid, and BAL fluid cell cultures were investigated for IL-18 estimation by ELISA. Analysis of IL-18 and IFN-gamma gene expression was carried out before and after LPS stimulation.

RESULTS

BD patients had significantly elevated levels of IL-18 in BAL fluid compared with control disease and healthy subjects. Induction of IFN-gamma and IL-18 were observed from BD-BAL fluid cells both spontaneously and after LPS stimulation, at higher levels compared to silicosis patients and healthy subjects (HC). Spontaneously only BD BAL cells expressed IL-18 mRNA and IFN-gamma mRNA. Forty-eight hours after LPS stimulation IL-18 mRNA and IFN-gamma mRNA were observed in BD, silicosis and HC cells. Recombinant IL-18 induced IFN-gamma production in BD- BAL fluid cells.

CONCLUSION

Administration of IL-18 induced greater IFN-gamma production in BD-BAL fluid cells, than in normal BAL fluid cells. Our data indicate that IL-18 up-regulation is a feature of BD and suggest that IL-18 and IFN-gamma may contribute to the local inflammatory response in BD.

[Histology of the larynx]

The mucous membrane lining the interior of the larynx was studied in autopsy specimens taken from 21 infant larynxes, with ages ranging from 1 to 15 years. Only those larynxes in which the epithelial mucosal structures were preserved were set aside for study. A standard histological technique was applied. Paraffin sections were stained with haematoxylin-eosin, PAS, Masson's triple stain and orcine. The epithelium of the ventricles, ventricular bands and subglottis was found to be of respiratory type. On the vocal folds, the lining was non-keratinising squamous epithelium. These findings are consistent with those found in the literature. Findings that differed were as follows: the laryngeal surface of the epiglottis is classically described as having a respiratory type of epithelium, whereas we found it to be of non-keratinising stratified squamous type. The literature describes the epithelium of the ventricular bands as respiratory. While in our series we found stratified squamous in 56% and respiratory in 44%. Other findings are imprecise in the literature, and need definition; the finding of taste papillae in six cases without age correlation; and the richness of follicles in the lymphoid tissue at the epiglottis and ventricles of children aged more than 3 months.

Characterization of the Sinorhizobium meliloti genes encoding a functional dihydrodipicolinate synthase (dapA) and dihydrodipicolinate reductase (dapB)

In bacteria, the known pathways for diaminopimelate (DAP) and lysine biosynthesis share two key enzymes, dihydrodipicolinate synthase and dihydrodipicolinate reductase, encoded by the dapA and dapB genes, respectively. In rhizobia, these genes have not yet been genetically characterized. In this work, by sequence analysis, we identified two divergent open reading frames on the 140-MDa plasmid pRmeGR4b of Sinorhizobium meliloti strain GR4. Termed dapA and dapB, these encode products which show significant sequence similarities to DapA and DapB proteins, respectively. Escherichia coli DAP auxotrophs (dapA and dapB mutants) could be complemented with the pRmeGR4b dapA and dapB genes, indicating that these genes code for functional dihydrodipicolinate synthase and dihydrodipicolinate reductase, respectively. Reverse-transcriptase PCR analyses and beta-galactosidase assays using transcriptional dapA-lacZ and dapB-lacZ fusions suggest that these genes are constitutively expressed in S. meliloti. The dapA and dapB genes are not widely distributed in S. meliloti and appear to be specific for strains carrying pRmeGR4b-type plasmids.

The Sinorhizobium meliloti insertion sequence (IS) elements ISRm102F34-1/ISRm7 and ISRm220-13-5 belong to a new family of insertion sequence elements

The Sinorhizobium meliloti insertion sequence (IS) elements ISRm102F34-1 and ISRm220-13-5 are 1481 and 1550 base pairs (bp) in size, respectively. ISRm102F34-1 is bordered by 15 bp imperfect terminal inverted repeat sequences (two mismatches), whereas the terminal inverted repeat of ISRm220-13-5 has a length of 16 bp (two mismatches). Both insertion sequence elements generate a 6-bp target duplication upon transposition. The putative transposase enzymes of ISRm102F34-1 and ISRm220-13-5 consist of 449 or 448 amino acid residues with predicted molecular weights of 50.7 or 51.3 kDa and theoretical isoelectric points of 10.8 or 11.1, respectively. ISRm102F34-1 is identical in 98.9% of its nucleotide sequence to an apparently inactive copy of an insertion sequence element, designated ISRm7, which flanks the left-end of the nodule formation efficiency (nfe) region of plasmid pRmeGR4b of S. meliloti strain GR4. ISRm102F34-1 and ISRm220-13-5 are closely related since they show an overall identity of 57.0% at the nucleotide sequence level and of 47.3% at the deduced amino acid level of their putative transposases. Both insertion sequence elements displayed significant similarity to the Xanthomonas campestris ISXc6 and its homolog IS1478a. Since none of these insertion sequence elements could be allocated to existing families of insertion sequence elements, a new family is proposed. Analysis of the distribution of ISRm102F34-1/ISRm7 in various local S. meliloti populations sampled from Medicago sativa, Medicago sphaerocarpa and Melilotus alba host plants at different locations in Spain revealed its presence in 35% of the isolates with a copy number ranging from 1 to 5. Furthermore, ISRm102F34-1/ISRm7 homologs were identified in other rhizobial species.

Characterization and splicing in vivo of a Sinorhizobium meliloti group II intron associated with particular insertion sequences of the IS630-Tc1/IS3 retroposon superfamily

By sequence analysis of Sinorhizobium meliloti strain GR4 plasmid pRmeGR4b, we have identified a group II intron named RmInt1 inserted within the insertion sequence ISRm2011-2 of the IS630-Tc1/IS3 retroposon superfamily. Like some other group II introns, RmInt1 possesses, in addition to the structurally conserved ribozyme core, an open reading frame (ORF) with homology to reverse transcriptases. Using a T7 expression system in Escherichia coli, we show that the intron is active in splicing in vivo and that splicing efficiency requires the intron-encoded ORF, which suggests that the putative intron encoded protein has a maturase function. DNA hybridization studies indicate that intron RmInt1 is widespread within S. meliloti native populations and appears to be mostly located within this IS element. Nevertheless, some S. meliloti strains harbour one copy of RmInt1 at a different location. DNA sequence analysis of the 5' exon of one of these heterologous intron insertion sites revealed the presence of a putative IS element closely related to insertion sequence ISRm2011-2. The intron-binding sites (IBS1 and IBS2 motifs) are conserved, although a transition of a G-->A in the IBS1 has occurred. Our results demonstrate an association of intron RmInt1 with particular insertion sequences of the IS630-Tc1/IS3 retroposon superfamily that may have ensured the spread and maintenance of this group II intron in S. meliloti.

ISRm4-1 and ISRm9, two novel insertion sequences from Sinorhizobium meliloti

Two novel insertion sequences, ISRm4-1 and ISRm9 have been identified in Sinorhizobium meliloti. ISRm4-1 is 936-bp in length, flanked by 17-bp putative terminal inverted repeats and a putative target duplication of 3-bp. ISRm4-1 is a member of the IS5 family of insertion sequences, closely related to ISRm4. ISRm9 is 2797-bp in length and carries 25-bp inverted repeats with target duplication of 7-bp: ISRm9 belongs to the IS21 family of insertion elements. On the non-pSym plasmid pRmeGR4b from S. meliloti strain GR4, a copy of ISRm4-1 is interrupted at nucleotide 150 from its 5'-end by a copy of ISRm9. Whereas ISRm4-like elements are widespread in S. meliloti, the distribution of ISRm9 appears to be correlated to that of pRmeGR4b-type plasmids.

A new insertion sequence from Sinorhizobium meliloti with homology to IS1357 from Methylobacterium sp. and IS1452 from Acetobacter pasteurianus

The insertion sequence ISRm8 was identified by sequence analysis of the cryptic plasmid pRmeGR4b of Sinorhizobium meliloti GR4. ISRm8 is 1451 bp in length and carries 22/24-bp terminal imperfect inverted repeats with seven mismatches and a direct target site duplication of 3 bp. ISRm8 carries a unique open reading frame whose putative protein showed significant similarity to the insertion sequences IS1357 and IS1452, isolated from Methylobacterium sp. and Acetobacter pasteurianus, respectively. Two copies of this IS element were found in strain GR4; one of them is linked to plasmid pRmeGR4b, whereas the other is localized out of the non-pSym plasmids. In S. meliloti field populations ISRm8 shows a limited distribution (50% of the strains tested carry the IS element), with a copy number ranging from 1 to 6.

[Sequential and ultrastructural study of lactotroph response to stress in rats as a function of age]

In adult rats, ether inhalation stress stimulated basal serum prolactin (PRL) significantly, within a maximum delay of one minute. The same pattern was seen with immature animals of 15-20 and 30 days of age. In contrast, in 2 or 6 days old neonates, serum PRL concentrations remained unaffected by stress. This lack of responsiveness suggests the existence of a transient impairment of lactotroph hormones to stressful stimuli during postnatal life. This hypothesis has been controlled by ultrastructural exploration of lactotrophs. The distribution of organites and secretion grains in lactotrophs was similar in unstressed neonates and adult rats, but after ether stress, the distribution of secretion grains became different with age. Adult lactotrophs showed a peripheral secretion grains aspects indicating cells discharge. In the very young rats, the grains were distributed in the totality of the cytoplasm. These results confirm the existence, in the lactotrophs, of a refractory period to stress in the neonate rats.