The positive benefit of Lactobacillus paracasei NCC2461 ST11 in healthy volunteers with moderate to severe dandruff

Dandruff is a common persistent, relapsing inflammatory condition affecting the scalp. An imbalanced proportion of the major bacterial and fungal populations colonising the scalp, a skin barrier dysfunction, and hyperseborrhoea are three main etiological factors of dandruff. The efficacy of Lactobacillus paracasei NCC 2461 ST11 (ST11) to manage dandruff and to restore a balanced scalp microbiome was assessed. Sixty healthy male volunteers aged 18 to 60 years with moderate to severe dandruff consumed on a daily basis a sachet containing ST11 (1×109 cfu) or a placebo for 56 days. Clinical efficacy (free and adherent dandruff, erythema, scalp seborrhoea, global clinical score), subject self-assessments, safety reporting as well as scalp microbiota assessments were performed every two weeks (day 1, 15, 29, 43, 57 and 64/follow-up). Free and adherent dandruff, erythema and the global clinical score improved significantly (all P<0.05) over time in the ST11 group and as compared to the placebo when day 57 was compared to day 1. Self-assessments paralleled these findings. ST11 enhanced restoring the scalp microbiota after 56 days of supplementation when compared to the placebo. No adverse events were reported. Regular intake of ST11 over 56 days is safe and reduces significantly the severity of signs and symptoms of moderate to severe dandruff. Its efficacy is potentially due to its positive impact on the skin barrier and skin immune system.

Randomised double-blind placebo-controlled study of the effect of Lactobacillus paracasei NCC 2461 on skin reactivity

In recent decades, the prevalence of subjects with reactive skin has considerably increased in industrialised countries. 50% of women and 30% of men report cutaneous discomfort classified under reactive/sensitive skin. Several topical approaches have been proposed, in particular through improvement of galenic forms or protection of epidermal surface. We propose to act differently, deeply from inside the body via an innovative nutritional approach. To this purpose, Lactobacillus paracasei NCC 2461 (ST11) was selected because of its specific beneficial skin properties discovered in in vitro studies, i.e. diminution of neurogenic inflammation and promotion of the recovery of skin barrier function. We designed a randomised double-blind placebo-controlled clinical study with a two-month supplementation in two female treatment groups (n=32 per group). A capsaicin test was performed to monitor the time course of skin sensitivity. Moreover, transepidermal water loss was assessed to analyse the rate of skin barrier function recovery; dryness of the leg and roughness of the cheeks was investigated by a dermatologist as well as by self-assessment. The results of the present clinical trial show that oral supplementation with the probiotic decreases skin sensitivity and increases the rate of barrier function recovery. Thus, the data provide evidence that daily intake of ST11 could improve reactive skin condition.

Immune modulation property of Lactobacillus paracasei NCC2461 (ST11) strain and impact on skin defences

The gut intestinal tract harbours a complex microbiota. Disturbances in the microbiota composition have been associated with several immune dysfunctions such as inflammatory diseases. Specific strains of probiotics have shown to beneficially influence the composition and/or metabolic activity of the endogenous microbiota. Taking advantage of the plasticity of the immune system, the probiotic strain NCC2461 (i.e. ST11 or CNCM I-2116) supports and/or restores homeostasis in reaction to different physiopathological conditions. The potential of NCC2461 to modulate both mucosal and systemic immune functions led us to test its impact on skin physiology. Even though clear mechanisms explaining gut-skin interaction are still lacking, a set of experimental and clinical data reviewed herein have shown that NCC2461 exerts its effects beyond the gut and confers benefits at the skin level. It contributes to the reinforcement of skin barrier function, decreases skin sensitivity and modulates the skin immune system leading to the preservation of skin homeostasis.

Anti-inflammatory effects of Lacto-Wolfberry in a mouse model of experimental colitis

AIM: To investigate the anti-inflammatory properties of Lacto-Wolfberry (LWB), both in vitro and using a mouse model of experimental colitis.

METHODS: The effects of LWB on lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) and interleukin (IL)-6 secretion were assessed in a murine macrophage cell line. in vitro assessment also included characterizing the effects of LWB on the activation of NF-E2 related 2 pathway and inhibition of tumor necrosis factor-α (TNF-α)-induced nuclear factor-κB (NF-κB) activation, utilizing reporter cell lines. Following the in vitro assessment, the anti-inflammatory efficacy of an oral intervention with LWB was tested in vivo using a preclinical model of intestinal inflammation. Multiple outcomes including body weight, intestinal histology, colonic cytokine levels and anti-oxidative measures were investigated.

RESULTS: LWB reduced the LPS-mediated induction of ROS production [+LPS vs 1% LWB + LPS, 1590 ± 188.5 relative luminescence units (RLU) vs 389 ± 5.9 RLU, P < 0.001]. LWB was more effective than wolfberry alone in reducing LPS-induced IL-6 secretion in vitro (wolfberry vs 0.5% LWB, 15% ± 7.8% vs 64% ± 5%, P < 0.001). In addition, LWB increased reporter gene expression via the anti-oxidant response element activation (wolfberry vs LWB, 73% ± 6.9% vs 148% ± 28.3%, P < 0.001) and inhibited the TNF-α-induced activation of the NF-κB pathway (milk vs LWB, 10% ± 6.7% vs 35% ± 3.3%, P < 0.05). Furthermore, oral supplementation with LWB resulted in a reduction of macroscopic (-LWB vs +LWB, 5.39 ± 0.61 vs 3.66 ± 0.59, P = 0.0445) and histological scores (-LWB vs +LWB, 5.44 ± 0.32 vs 3.66 ± 0.59, P = 0.0087) in colitic mice. These effects were associated with a significant decrease in levels of inflammatory cytokines such as IL-1β (-LWB vs +LWB, 570 ± 245 μg/L vs 89 ± 38 μg/L, P = 0.0106), keratinocyte-derived chemokine/growth regulated protein-α (-LWB vs +LWB, 184 ± 49 μg/L vs 75 ± 20 μg/L, P = 0.0244), IL-6 (-LWB vs +LWB, 318 ± 99 μg/L vs 117 ± 18 μg/L, P = 0.0315) and other pro-inflammatory proteins such as cyclooxygenase-2 (-LWB vs +LWB, 0.95 ± 0.12 AU vs 0.36 ± 0.11 AU, P = 0.0036) and phosphorylated signal transducer and activator of transcription-3 (-LWB vs +LWB, 0.51 ± 0.15 AU vs 0.1 ± 0.04 AU, P = 0.057). Moreover, antioxidant biomarkers, including expression of gene encoding for the glutathione peroxidase, in the colon and the plasma anti-oxidant capacity were significantly increased by supplementation with LWB (-LWB vs +LWB, 1.2 ± 0.21 mmol/L vs 2.1 ± 0.19 mmol/L, P = 0.0095).

CONCLUSION: These results demonstrate the anti-inflammatory properties of LWB and suggest that the underlying mechanism is at least in part due to NF-κB inhibition and improved anti-oxidative capacity.

Nigella sativa (black cumin) seed extract alleviates symptoms of allergic diarrhea in mice, involving opioid receptors

The incidence of food hypersensitivity and food allergies is on the rise and new treatment approaches are needed. We investigated whether N. sativa, one of its components, thymoquinone, or synthetic opioid receptor (OR)-agonists can alleviate food allergy. Hence, ovalbumin (OVA)-sensitized BALB/c-mice were pre-treated either with a hexanic N. sativa seed extract, thymoquinone, kappa-(U50'4889) or mu-OR-agonists (DAMGO) and subsequently challenged intra-gastrically with OVA. All 4 treatments significantly decreased clinical scores of OVA-induced diarrhea. N. sativa seed extract, thymoquinone, and U50'488 also decreased intestinal mast cell numbers and plasma mouse mast cell protease-1 (MMCP-1). DAMGO, in contrast, had no effect on mast cell parameters but decreased IFNγ, IL-4, IL-5, and IL-10 concentration after ex vivo re-stimulation of mesenteric lymphocytes. The effects on allergy symptoms were reversible by OR-antagonist pre-treatment, whereas most of the effects on immunological parameter were not. We demonstrate that N. sativa seed extract significantly improves symptoms and immune parameters in murine OVA-induced allergic diarrhea; this effect is at least partially mediated by thymoquinone. ORs may also be involved and could be a new target for intestinal allergy symptom alleviation. N. sativa seed extract seems to be a promising candidate for nutritional interventions in humans with food allergy.

Probiotics for photoprotection

Specific strains of probiotic, have been identified as beneficial to influence the composition and/or metabolic activity of the endogenous microbiota and some of these strains have been also shown to inhibit the growth of a wide range of enteropathogens. The first aim of using probiotics has been to improve the composition of the intestinal microbiota from a potentially harmful composition towards a composition that would be beneficial to the host.Beyond their capacity to influence positively the composition of the intestinal microbiota, several lines of evidence suggest that some probiotic bacteria can modulate the immune system both at the local and systemic levels thereby improving immune defense mechanisms and/or downregulate immune disorders such as allergies or intestinal inflammation.Skin reflects the general health status and aging. Different human trials widely suggest that probiotic supplementation might be useful in the management of atopic dermatitis. Based on these properties it appears that, beyond the gut, probiotics might exert their benefits at the skin level.In a randomized double blind placebo-controlled clinical trial, we investigated whether the probiotic bacteria Lactobacillus johnsonii NCC 533 (La1) could modulate the cutaneous immune homeostasis altered by solar-simulated UV exposure in humans. After, UV exposure to twice 1.5 MED, we demonstrated that La1 intake facilitated an earlier recovery of Epidermal cells allostimulatory function. Thus, this clinical data strengthen the assumption that certain probiotics can contribute to modulate skin immune system leading to the preservation of the skin homeostasis. Altogether the data affords the possibility of designing new strategies based on a nutritional approach for the prevention of UV-induced damaging effects.

Bifidobacterium lactis attenuates onset of inflammation in a murine model of colitis

AIM

To assess the anti-inflammatory effect of the probiotic Bifidobacterium lactis (B. lactis) in an adoptive transfer model of colitis.

METHODS

Donor and recipient mice received either B. lactis or bacterial culture medium as control (deMan Rogosa Sharpe) in drinking water for one week prior to transfer of a mix of naive and regulatory T cells until sacrifice.

RESULTS

All recipient mice developed signs of colonic inflammation, but a significant reduction of weight loss was observed in B. lactis-fed recipient mice compared to control mice. Moreover, a trend toward a diminution of mucosal thickness and attenuated epithelial damage was revealed. Colonic expression of pro-inflammatory and T cell markers was significantly reduced in B. lactis-fed recipient mice compared to controls. Concomitantly, forkhead box protein 3, a marker of regulatory T cells, was significantly up-regulated by B. lactis.

CONCLUSION

Daily oral administration of B. lactis was able to reduce inflammatory and T cells mediators and to promote regulatory T cells specific markers in a mouse model of colitis.

Treatment with Bifidobacterium bifidum 17 partially protects mice from Th1-driven inflammation in a chemically induced model of colitis

Probiotics have been suggested as an alternative therapeutical approach in the intervention of inflammatory disorders of the gastrointestinal tract (GIT). Application of single strains or probiotic mixtures has shown promising results in animal models and patients of inflammatory bowel disease (IBD). We recently demonstrated potent inhibitory capacity of a Bifidobacterium bifidum S17 on LPS-induced inflammatory events in cell culture models using intestinal epithelial cells and verified these anti-inflammatory effects in two mouse models of colitis. In the present study we analyze the anti-inflammatory effect of this potential probiotic strain in a chemically-induced model of colitis in C57BL/6 mice. This model is characterized by a strong type 1T helper (Th1) response resembling Crohn's disease, one of the two most prevalent forms of IBD. We performed macroscopic analysis and determined the effect of B. bifidum S17 on the cytokine balance in biopsies of the colonic mucosa. While treatment with B. bifidum S17 only had a marginal effect on weight loss, no difference was observed in the macroscopic parameters. However, a significant reduction in histology scores and the levels of pro-inflammatory cytokines interleukin 1β (IL-1β), interleukin 6 (IL-6), keratinocyte-derived chemokine (KC) and the inflammatory markers cyclooxigenase 2 (Cox-2) and myeloperoxidase (MPO) was observed. These results indicate that treatment with B. bifidum S17 is able to partially inhibit the strong Th1-driven intestinal inflammation induced in our model of colitis.

Opioid receptors are targets for alleviation of allergen-induced diarrhea and modification of immune parameters in mice (97.3)

So far, allergen avoidance is the most efficient treatment for individuals suffering from food-allergies. Since this almost always results in impairment of quality of life, new therapeutic concepts are needed. As opioid receptor (OR) expression has been demonstrated on various immune cells and as they have been shown to influence intestinal inflammation and motility, we were interested to study if OR are also involved in allergen-induced diarrhea. Ovalbumin-sensitized (OVA) Balb/c-mice were orally challenged with OVA, resulting in transient diarrhea and changes of plasma total IgE, OVA-specific IgE and mouse-mast-cell-protease-1(MMCP-1). Animals were pre-treated with kappa- or mu-OR-agonists (U50’488, DAMGO) and/or OR-antagonist and results were compared to controls. U50’488 and DAMGO significantly delayed the onset and decreased the severity of OVA-induced diarrhea. Animals receiving U50’488 showed lower total IgE and MMCP-1 concentration compared to controls, whereas DAMGO only showed a minimal influence on MMCP-1 release. The positive effect on diarrhea severity was partially reversed by pre-treatment with OR-antagonists. To our knowledge this is the first time that ORs are implicated as targets in modulation of food allergy. The changes in immune parameters with one of the OR-agonist suggest mechanisms extending beyond local intestinal motility and secretory regulation. Targeting of kappa- and/or mu-OR might prove valuable in alleviation of food allergies in the future.

Metabolic assessment of gradual development of moderate experimental colitis in IL-10 deficient mice

Evidence has linked genetic predisposition and environmental exposures to the worldwide pandemic of inflammatory bowel diseases (IBD), but underlying biochemical events remain largely undefined. Here, we studied the gradual development of colitis in Interleukin 10 deficient mice using a combination of (i) histopathological analysis of intestinal sections, (ii) metabolic profiling of blood plasma, and (iii) measurement of plasma inflammatory biomarkers. Data integration using chemometric tools, including Independent Component Analysis, provided a new strategy for measuring and mapping the metabolic effects associated with the development of intestinal inflammation at the age of 1, 8, 16, and 24 weeks. Chronic inflammation appeared at 8 weeks and onward, and was associated with altered cecum and colon morphologies and increased inflammatory cell infiltration into the mucosa and the submucosa. Blood plasma profiles provided additional evidence of loss of energy homeostasis, impaired metabolism of lipoproteins and glycosylated proteins. In particular, IL-10-/-mice were characterized by decreased levels of VLDL and increased concentrations of LDL and polyunsaturated fatty acids, which are related to the etiology of IBD. Moreover, higher levels of lactate, pyruvate, citrate and lowered glucose suggested increased fatty acid oxidation and glycolysis, while higher levels of free amino acids reflected muscle atrophy, breakdown of proteins and interconversions of amino acids to produce energy. These integrated system investigations demonstrate the potential of metabonomics for investigating the mechanistic basis of IBD, and it will provide novel avenues for management of IBD.

Interleukin-18 protein level is upregulated in adipose tissue of obese mice

In this study, we investigated the regulation of Interleukin-18 (IL-18) and caspase-1 mRNA and protein levels in adipose and liver tissue of obese (ob/ob) mice compared with ob/+ mice. In ob/ob mice, which have a twofold higher IL-18 plasma level as compared with lean mice, IL-18 mRNA expression was significantly reduced by 1.6-fold in adipose tissue, whereas protein level was enhanced fourfold as compared with ob/+ mice. However, caspase-1 mRNA expression and activity were significantly enhanced in adipose tissue of ob/ob mice. Conversely, both IL-18 mRNA and protein levels were slightly enhanced, but caspase-1 activity was reduced in liver of ob/ob mice as compared with lean mice. In conclusion, we show that adipose and hepatic IL-18 protein expressions are increased in obese mice. However, in contrast to liver, the adipose IL-18 protein level appears to be upregulated through a post-transcriptional mechanism probably involving caspase-1.

micro-Opioid receptor activation prevents acute hepatic inflammation and cell death

BACKGROUND AND AIMS

The detrimental impact of opioid agonist on the clinical management of inflammatory diseases remains elusive. Given the anti-inflammatory properties of the mu-opioid receptor (MOR) agonists at the intestinal barrier, we hypothesised that MOR activation might also dampen acute hepatic inflammation and cell death-major determinants in the pathogenesis of liver diseases.

PATIENTS AND METHODS

The expression of MOR in liver biopsy specimens and peripheral blood mononuclear cells of untreated patients with chronic hepatitis C virus infection and controls, primary hepatocytes and cell lines was determined by quantitative PCR, immunoblotting and/or immunohistochemistry. The effects of peripheral MOR agonist (d-Ala2,NMe-Phe4,Gly5-ol (DAMGO)) and/or antagonist (naloxone methiodide) were explored in two models of acute hepatitis in mice. MOR-deficient mice were used to evaluate the essential regulatory role of MOR during carbon tetrachloride (CCl(4))-induced hepatitis. The role of DAMGO in cell death was investigated using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) analysis and quantification of lactate dehydrogenase release.

RESULTS

The key role of MOR in the prevention of acute hepatic inflammation and cell death in vivo and in vitro is reported. Whereas MOR gene expression increased transiently in the model of acute liver injury and TNFalpha-treated HepG2 cells, an impaired expression of MOR mRNA in human chronic hepatitis C samples was found. Furthermore, preventive administration of the selective MOR agonist DAMGO enhanced hepatoprotective-signalling pathways in vivo that were blocked by using naloxone methiodide. Consistently, genetic and pharmacological inhibition of MOR enhanced the severity associated with experimental hepatotoxin-induced hepatitis. Finally, treatment with DAMGO was shown to prevent cell death in vitro in HepG2 cells in a MOR-dependent manner and to prevent concanavalin A- and CCl(4)-induced cell death in vivo, providing a possible explanation for the anti-inflammatory role of MOR activation in the liver.

CONCLUSIONS

The results indicate that MOR agonists may prevent acute hepatitis and hold promising therapeutic use to maintain remission in both chronic inflammatory bowel and liver diseases.

CD8+ cytotoxic T cells induce relapsing colitis in normal mice

BACKGROUND & AIMS

Most mouse models of IBD have emphasized an effector role of type-1 CD4+ T cells in colitis. The aim of this study was to develop a model of antigen-specific relapsing colitis to investigate the relative contribution of CD4+ and CD8+ effectors.

METHODS

Balb/C mice were sensitized and challenged with a suboptimal dose of 2.4 dinitrobenzene sulfonic acid to generate a colonic delayed-type hypersensitivity response. The respective role of CD4+ and CD8+ T cells in the initiation of colitis was analyzed by in vivo monoclonal antibody depletion and cell-transfer experiments. Dynamic and function of the colitogenic effectors were studied by immunohistochemistry, fluorescence-activated cell sorter analysis, enzyme-linked immunospot assay, quantitative polymerase chain reaction, and in vivo CTL assays.

RESULTS

Relapsing colitis rapidly occurred only after challenge of previously sensitized mice. Interferon-gamma-producing cytotoxic CD8+ T cells (Tc1) specific for hapten-modified self-proteins were generated in colon-draining lymph nodes on day 5 after sensitization, before the onset of disease. These CD8+ T cells were rapidly recruited upon challenge into colon lamina propria as granzyme B-expressing effectors exerting ex vivo cytotoxicity against syngeneic hapten-modified colonic epithelial cells. Colitis was prevented by in vivo antibody depletion of CD8+, but not of CD4+, T cells and could be induced in naive recipients within 48 hours after transfer of CD8+, but not CD4+, T cells purified from sensitized mice.

CONCLUSIONS

Our data show that antigen-specific CD8+ T cells can induce relapsing colitis in normal mice and suggest that the cytolytic function of CD8 Tc1 against epithelial cells may initiate the intestinal inflammatory process.

Anti-inflammatory effects of bifidobacteria by inhibition of LPS-induced NF-κB activation

AIM: Different strains of bifidobacteria were analysed for their effects on HT-29 intestinal epithelial cells (IECs) in in vitro models both of the non-inflamed and inflamed intestinal epithelium.

METHODS: A reporter gene system in HT-29 cells was used to measure levels of NF-κB activation after challenge with bifidobacteria or after bacterial pre-treatment following LPS challenge. IL-8 protein and pro-inflammatory gene expression was investigated using normal HT-29 cells.

RESULTS: None of the bifidobacteria tested induced activation of nuclear factor κB (NF-κB) indicating that bifidobacteria themselves do not induce inflammatory events in IECs. However, six out of eight bifidobacteria tested inhibited lipopolysaccharide- (LPS-) induced NF-κB activation in a dose- and strain-dependent manner. In contrast, NF-κB activation in response to challenge with tumor necrosis factor-α (TNF-α) was affected by none of the tested bifidobacteria, indicating that the inhibitory effect of bifidobacteria is specific for LPS-induced inflammation in IECs. As shown with two of the six inhibition-positive bifidobacteria, LPS-induced inhibition of NF-κB activation was accompanied by a dose-dependent decrease of interleukin 8 (IL-8) secretion and by lower mRNA levels for IL-8, TNF-α, cyclooxygenase 2 (Cox-2), and intercellular adhesion molecule 1 (ICAM-1).

CONCLUSION: Some strains of bifidobacteria are effective in inhibiting LPS-induced inflammation and thus might be appropriate candidates for probiotic intervention in chronic intestinal inflammation.

Mu opioid receptor expression is increased in inflammatory bowel diseases: implications for homeostatic intestinal inflammation

BACKGROUND AND AIMS

Recent studies with mu opioid receptor (MOR) deficient mice support a physiological anti-inflammatory effect of MOR at the colon interface. To better understand the potential pharmacological effect of certain opiates in inflammatory bowel diseases (IBD), we (1) evaluated the regulation in vivo and in vitro of human MOR expression by inflammation; and (2) tested the potential anti-inflammatory function of a specific opiate (DALDA) in inflamed and resting human mucosa.

PATIENTS AND METHODS

Expression of MOR mRNA and protein was evaluated in healthy and inflamed small bowel and colonic tissues, isolated peripheral blood mononuclear cells and purified monocytes, and CD4+ and CD8+ T cells from healthy donors and IBD patients. The effect of cytokines and nuclear factor kappaB (NFkappaB) activation on MOR expression in lymphocyte T and monocytic human cell lines was assessed. Finally, DALDA induced anti-inflammatory effect was investigated in mucosal explants from controls and IBD patients.

RESULTS

MOR was expressed in ileal and colonic enteric neurones as well as in immunocytes such as myeloid cells and CD4+ and CD8+ T cells. Overexpressed in active IBD mucosa, MOR was significantly enhanced by cytokines and repressed by NFkappaB inhibitor in myeloid and lymphocytic cell lines. Furthermore, ex vivo DALDA treatment dampened tumour necrosis factor alpha mRNA expression in the colon of active IBD patients.

CONCLUSIONS

Given the increased expression of MOR and the ex vivo beneficial effect of DALDA in active IBD, natural and/or synthetic opioid agonists could help to prevent overt pathological intestinal inflammation.

Changes in enteric neurone phenotype and intestinal functions in a transgenic mouse model of enteric glia disruption

AIMS

The influence of enteric glia on the regulation of intestinal functions is unknown. Our aim was to determine the phenotype of enteric neurones in a model of glia alterations and the putative changes in intestinal motility and permeability.

METHODS

Transgenic mice expressing haemagglutinin (HA) in glia were used. Glia disruption was induced by injection of activated HA specific CD8+ T cells. Control mice consisted of non-transgenic littermates injected with activated HA specific CD8+ T cells. Immunohistochemical staining for choline acetyltransferase (ChAT), substance P (SP), vasoactive intestinal peptide (VIP), and nitric oxide synthase (NOS) was performed on jejunal submucosal plexus (SMP) and myenteric plexus (MP). Neurally induced jejunal muscle activity was characterised in vitro. Gastrointestinal transit and paracellular permeability were measured using fluorescein isothiocyanate-dextran markers.

RESULTS

CD3 positive T cells infiltrates were observed in the MP of transgenic mice. In the SMP, the proportions of VIP and SP positive neurones decreased in transgenic mice compared with control mice. ChAT remained unchanged. In the MP, the proportions of ChAT and NOS positive neurones increased and decreased, respectively, in transgenic mice. In contrast, VIP and SP remained unchanged. Neurally mediated jejunal relaxation was lower in transgenic mice than in controls. This relaxation was reduced by NG-nitro-L-arginine methyl ester in control mice but not in transgenic mice. Gastrointestinal transit was delayed and intestinal permeability increased in transgenic mice compared with control mice.

CONCLUSION

Glia disruption induces changes in the neurochemical coding of enteric neurones, which may partly be responsible for dysfunctions in intestinal motility and permeability.

Impaired expression of the peroxisome proliferator-activated receptor alpha during hepatitis C virus infection

BACKGROUND AND AIMS

Liver inflammation, fibrosis, and dyslipidemia are common features in patients with chronic hepatitis C virus (HCV) infection. Because peroxisome proliferator-activated receptor alpha (PPARalpha) is highly expressed in the liver and is involved in the regulation of lipid metabolism and inflammation, we sought to determine whether HCV infection may locally impair PPARalpha expression and activity.

METHODS

PPARalpha expression was investigated in liver biopsy specimens of 86 untreated patients with HCV infection and controls, by using real-time polymerase chain reaction (PCR), Western blot analysis, and immunohistochemistry. PPARalpha activity was assessed by quantification of the key gene target carnitine palmitoyl acyl-CoA transferase 1 (CPT1A) messenger RNA (mRNA). The influence of HCV core protein on PPARalpha mRNA expression was analyzed in vitro by real-time PCR in HCV core-expressing HepG2 cells activated with the PPARalpha ligand fenofibric acid.

RESULTS

Hepatic concentrations of PPARalpha and CPT1A expressed by hepatocytes were impaired profoundly in the livers of untreated patients with HCV infection compared with controls. A mean decrease of 85% in PPARalpha mRNA expression paralleled with a lack of CPT1A mRNA induction also were observed in HCV core-expressing HepG2 cells compared with controls.

CONCLUSIONS

HCV infection is related to altered expression and function of the anti-inflammatory nuclear receptor PPARalpha. These results identify hepatic PPARalpha as one mechanism underlying the pathogenesis of HCV infection, and as a new therapeutic target in traditional treatment of HCV-induced liver injury.

Anti-inflammatory properties of the mu opioid receptor support its use in the treatment of colon inflammation

The physiologic role of the mu opioid receptor (MOR) in gut nociception, motility, and secretion is well established. To evaluate whether MOR may also be involved in controlling gut inflammation, we first showed that subcutaneous administration of selective peripheral MOR agonists, named DALDA and DAMGO, significantly reduces inflammation in two experimental models of colitis induced by administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) or peripheral expansion of CD4(+) T cells in mice. This therapeutic effect was almost completely abolished by concomitant administration of the opioid antagonist naloxone. Evidence of a genetic role for MOR in the control of gut inflammation was provided by showing that MOR-deficient mice were highly susceptible to colon inflammation, with a 50% mortality rate occurring 3 days after TNBS administration. The mechanistic basis of these observations suggests that the anti-inflammatory effects of MOR in the colon are mediated through the regulation of cytokine production and T cell proliferation, two important immunologic events required for the development of colon inflammation in mice and patients with inflammatory bowel disease (IBD). These data provide evidence that MOR plays a role in the control of gut inflammation and suggest that MOR agonists might be new therapeutic molecules in IBD.

Anti-inflammatory properties of the mu opioid receptor support its use in the treatment of colon inflammation

The physiologic role of the mu opioid receptor (MOR) in gut nociception, motility, and secretion is well established. To evaluate whether MOR may also be involved in controlling gut inflammation, we first showed that subcutaneous administration of selective peripheral MOR agonists, named DALDA and DAMGO, significantly reduces inflammation in two experimental models of colitis induced by administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) or peripheral expansion of CD4(+) T cells in mice. This therapeutic effect was almost completely abolished by concomitant administration of the opioid antagonist naloxone. Evidence of a genetic role for MOR in the control of gut inflammation was provided by showing that MOR-deficient mice were highly susceptible to colon inflammation, with a 50% mortality rate occurring 3 days after TNBS administration. The mechanistic basis of these observations suggests that the anti-inflammatory effects of MOR in the colon are mediated through the regulation of cytokine production and T cell proliferation, two important immunologic events required for the development of colon inflammation in mice and patients with inflammatory bowel disease (IBD). These data provide evidence that MOR plays a role in the control of gut inflammation and suggest that MOR agonists might be new therapeutic molecules in IBD.

Acute pure spontaneous subdural haematoma from ruptured intracranial aneurysms

SUMMARY

Acute subdural haematoma (ASDH) is rarely caused by an aneurysmal rupture. We report four cases of pure acute subdural haematomas caused by ruptured intracranial aneurysms. Aneurysms were localized in the posterior communicating artery in two cases, in the anterior communicating artery in one case and in the middle cerebral artery in one other case. Possible mechanisms for this type of aneurysmal bleeding are discussed. A good prognosis for these patients can be expected with rapid evacuation of the haematoma (in case of high intracranial pressure and midline structure shift), and treatment of the aneurysm (surgical clipping or endovascular treatment). Our report demonstrates the utility of angiography in the evaluation of nontraumatic acute subdural haematomas. Angiography has to be performed before haematoma evacuation or just after if the patient requires urgent surgery in case of intracranial hypertension. Aneurysms may require surgical clipping or endovascular treatment.