Alteration of colonic excitatory tachykininergic motility and enteric inflammation following dopaminergic nigrostriatal neurodegeneration

Background: Parkinson's disease (PD) is frequently associated with gastrointestinal (GI) symptoms, including constipation and defecatory dysfunctions. The mechanisms underlying such disorders are still largely unknown, although the occurrence of a bowel inflammatory condition has been hypothesized. This study examined the impact of central dopaminergic degeneration, induced by intranigral injection of 6-hydroxydopamine (6-OHDA), on distal colonic excitatory tachykininergic motility in rats. Methods: Animals were euthanized 4 and 8 weeks after 6-OHDA injection. Tachykininergic contractions, elicited by electrical stimulation or exogenous substance P (SP), were recorded in vitro from longitudinal muscle colonic preparations. SP, tachykininergic NK1 receptor, and glial fibrillary acidic protein (GFAP) expression, as well as the density of eosinophils and mast cells in the colonic wall, were examined by immunohistochemical analysis. Malondialdehyde (MDA, colorimetric assay), TNF, and IL-1 beta (ELISA assay) levels were also examined. The polarization of peritoneal macrophages was evaluated by real-time PCR. Results: In colonic preparations, electrically and SP-evoked tachykininergic contractions were increased in 6-OHDA rats. Immunohistochemistry displayed an increase in SP and GFAP levels in the myenteric plexus, as well as NK1 receptor expression in the colonic muscle layer of 6-OHDA rats. MDA, TNF, and IL-1 beta levels were increased also in colonic tissues from 6-OHDA rats. In 6-OHDA rats, the number of eosinophils and mast cells was increased as compared with control animals, and peritoneal macrophages polarized towards a pro-inflammatory phenotype. Conclusions: The results indicate that the induction of central nigrostriatal dopaminergic degeneration is followed by bowel inflammation associated with increased oxidative stress, increase in pro-inflammatory cytokine levels, activation of enteric glia and inflammatory cells, and enhancement of colonic excitatory tachykininergic motility

Immunohistochemical localization of histidine-rich glycoprotein in human skeletal muscle: preferential distribution of the protein at the sarcomeric I-band

Histidine-rich glycoprotein (HRG) is a relatively abundant plasma protein that is synthesized by parenchymal liver cells. Using Western blot analysis and immunoperoxidase techniques, we have previously shown the presence of HRG in human skeletal muscle. This paper reports the results of immunofluorescence experiments carried out on sections of human normal skeletal muscle biopsies to investigate the subcellular localization of HRG. The HRG localization was also compared with that of skeletal muscle AMP deaminase (AMPD1), since we have previously described an association of the enzyme with the protein. The obtained results give evidence for a preferential localization of HRG at the I-band level, where it shows the same distribution of actin and where AMPD1 is present in major concentration

Enteric dysfunctions in experimental Parkinson's disease: alterations of excitatory cholinergic neurotransmission regulating colonic motility in rats

Parkinson's disease (PD) is frequently associated with gastrointestinal symptoms, mostly represented by constipation and defecatory dysfunctions. This study examined the impact of central dopaminergic denervation, induced by injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle, on distal colonic excitatory cholinergic neuromotor activity in rats. Animals were euthanized 4 and 8 weeks after 6-OHDA injection. In vivo colonic transit was evaluated by radiological assay. Electrically and carbachol-induced cholinergic contractions were recorded in vitro from longitudinal and circular muscle colonic preparations, while acetylcholine levels were assayed in their incubation media. Choline acetyltransferase (ChAT), HuC/D (pan-neuronal marker), muscarinic M2 and M3 receptors. As compared with control rats, at week 4 6-OHDA-treated animals displayed the following changes: decreased in vivo colonic transit rate; impaired electrically evoked neurogenic cholinergic contractions; enhanced carbachol-induced contractions; decreased basal and electrically stimulated acetylcholine release from colonic tissues; decreased ChAT immunopositivity in the neuromuscular layer; unchanged density of HuC/D immunoreactive myenteric neurons; increased expression of colonic muscarinic M2 and M3 receptors. The majority of such alterations were detected also at week 8 post-6-OHDA injection. These findings indicate that central nigrostriatal dopaminergic denervation is associated with an impaired excitatory neurotransmission characterized by a loss of myenteric neuronal ChAT positivity and decrease in acetylcholine release, resulting in a dysregulated smooth muscle motor activity, which likely contributes to the concomitant decrease in colonic transit rate

Fibrotic and Vascular Remodelling of Colonic Wall in Patients with Active Ulcerative Colitis

open16noIntestinal fibrosis is a complication of inflammatory bowel disease [IBD]. Although fibrostenosis is a rare event in ulcerative colitis [UC], there is evidence that a fibrotic rearrangement of the colon occurs in the later stages. This is a retrospective study aimed at examining the histopathological features of the colonic wall in both short-lasting [SL] and long-lasting [LL] UC. Surgical samples of left colon from non-stenotic SL [a parts per thousand currency sign 3 years, n = 9] and LL [a parts per thousand yen 10 years, n = 10] UC patients with active disease were compared with control colonic tissues from cancer patients without UC [n = 12] to assess: collagen and elastic fibres by histochemistry; vascular networks [CD31/CD105/nestin] by immunofluorescence; parameters of fibrosis [types I and III collagen, fibronectin, RhoA, alpha-smooth muscle actin [alpha-SMA], desmin, vimentin], and proliferation [proliferating nuclear antigen [PCNA]] by western blot and/or immunolabelling. Colonic tissue from both SL-UC and LL-UC showed tunica muscularis thickening and transmural activated neovessels [displaying both proliferating CD105-positive endothelial cells and activated nestin-positive pericytes], as compared with controls. In LL-UC, the increased collagen deposition was associated with an up-regulation of tissue fibrotic markers [collagen I and III, fibronectin, vimentin, RhoA], an enhancement of proliferation [PCNA] and, along with a loss of elastic fibres, a rearrangement of the tunica muscularis towards a fibrotic phenotype. A significant transmural fibrotic thickening occurs in colonic tissue from LL-UC, together with a cellular fibrotic switch in the tunica muscularis. A full-thickness angiogenesis is also evident in both SL- and LL-UC with active disease, as compared with controls.openIppolito, Chiara; Colucci, Rocchina; Segnani, Cristina; Errede, Mariella; Girolamo, Francesco; Virgintino, Daniela; Dolfi, Amelio; Tirotta, Erika; Buccianti, Piero; Di Candio, Giulio; Campani, Daniela; Castagna, Maura; Bassotti, Gabrio; Villanacci, Vincenzo; Blandizzi, Corrado; Bernardini, NunziaIppolito, Chiara; Colucci, ROCCHINA LUCIA; Segnani, Cristina; Errede, Mariella; Girolamo, Francesco; Virgintino, Daniela; Dolfi, Amelio; Tirotta, Erika; Buccianti, Piero; Di Candio, Giulio; Campani, Daniela; Castagna, Maura; Bassotti, Gabrio; Villanacci, Vincenzo; Blandizzi, Corrado; Bernardini, Nunzi

Tau Modulates VGluT1 Expression

Abstract Tau displacement from microtubules is the first step in the onset of tauopathies and is followed by toxic protein aggregation. However, other non-canonical functions of Tau might have a role in these pathologies. Here, we demonstrate that a small amount of Tau localizes in the nuclear compartment and accumulates in both the soluble and chromatin-bound fractions. We show that favoring Tau nuclear translocation and accumulation, by Tau overexpression or detachment from MTs, increases the expression of VGluT1, a disease-relevant gene directly involved in glutamatergic synaptic transmission. Remarkably, the P301L mutation, related to frontotemporal dementia FTDP-17, impairs this mechanism leading to a loss of function. Altogether, our results provide the demonstration of a direct physiological role of Tau on gene expression. Alterations of this mechanism may be at the basis of the onset of neurodegeneration

Hyaluronic acid alone versus hyaluronic acid associated with adelmidrol for intra-articular treatment of knee osteoarthritis: a long-term follow-up

Background: Hyaluronic acid (HA) has been used for many years for intra-articular treatment of knee osteoarthritis with satisfactory results. HA associated with Adelmidrol – an anti-neuroinflammatory compound – have been only recently introduced in orthopedic clinical practice with good preliminary results. Objective: To investigate whether HA associated with Adelmidrol provides better results than HA alone. Methods: Two cohorts of patients with moderate knee osteoarthritis were treated. Cohort 1 received 5 weekly intra-articular injections of HA during 2017 while Cohort 2, 4 weekly intra-articular injections of HA associated with Adelmidrol during 2018. The patients of the two Cohorts were assessed by WOMAC scale, SF-12 questionnaire and PGIC scale at 1 week (T0), 6 months (T1), 1 year (T2), and 2 years (T3) after the end of treatment. All the data were statistically analyzed. A p-value of <0.05 was considered statistically significant. Results: According to the WOMAC Scale Cohort 1 had higher mean scores than Cohort 2 at each follow-up time, with a statistically significant difference between the two cohorts at T3 (p<0.03) for all the WOMAC components, except for Stiffness. WOMAC Total mean score worsened statistically significantly only in Cohort 1, from T1 to T3 (T2 vs T1: p=0.0033; T3 vs T2: p=0.0007). The same happened for WOMAC Physical Function (T2 vs T1: p=0.0146; T3 vs T2: p=0.0046) and WOMAC Pain (T2 vs T1: p=0.0004; T3 vs T2: p=0.0002). WOMAC Stiffness worsened statistically significantly in Cohort 1 from T2 to T3 (T3 vs T2: p=0.0041), while in Cohort 2 no change on WOMAC scale was statistically significant at any time-point, for any components. The mean scores of the SF-12 questionnaire were better in Cohort 2 than in Cohort 1 at each follow-up time for both the Physical and the Mental components, with a statistically significant difference between the two groups for the latter, at T0 (p=0.0001). In both cohorts the mean score of the Physical component decreased from T0 to T3, but the difference was not statistically significant between the two groups (p=0.25). The mean score of the Mental component slightly increased in Cohort 1 and decreased in Cohort 2, without statistically significant differences between the two groups at any time-point. PGIC showed that Cohort 2 scored significantly better than Cohort 1 at T3 (p=0.0336). Conclusions: Overall, HA associated with Adelmidrol gave better long-term results than HA alone

Vascular Dysfunction in a Mouse Model of Rett Syndrome and Effects of Curcumin Treatment

Mutations in the coding sequence of the X-linked gene MeCP2 (Methyl CpG–binding protein) are present in around 80% of patients with Rett Syndrome, a common cause of intellectual disability in female and to date without any effective pharmacological treatment. A relevant, and so far unexplored feature of RTT patients, is a marked reduction in peripheral circulation. To investigate the relationship between loss of MeCP2 and this clinical aspect, we used the MeCP2 null mouse model B6.129SF1-MeCP2tm1Jae for functional and pharmacological studies. Functional experiments were performed on isolated resistance mesenteric vessels, mounted on a pressurized myograph. Vessels from female MeCP2(+/−) mice show a reduced endothelium-dependent relaxation, due to a reduced Nitric Oxide (NO) availability secondary to an increased Reactive Oxygen Species (ROS) generation. Such functional aspects are associated with an intravascular increase in superoxide anion production, and a decreased vascular eNOS expression. These alterations are reversed by curcumin administration (5% (w/w) dietary curcumin for 21 days), which restores endothelial NO availability, decreases intravascular ROS production and normalizes vascular eNOS gene expression. In conclusion our findings highlight alterations in the vascular/endothelial system in the absence of a correct function of MeCP2, and uncover related cellular/molecular mechanisms that are rescued by an anti-oxidant treatment