Relation between microRNA-155 and inflammatory mediators in multiple sclerosis.

Multiple sclerosis (MS) is a complex autoimmune condition affecting the central nervous system characterized by axonal damage, demyelination, and chronic inflammation. Multiple molecular and cellular components mediate neuroinflammation in MS. In human macrophages and microglia, miRNA-155 is an essential proinflammatory noncoding RNA that regulates phenotypic and functional polarization properties. This study was conducted to detect the plasma level of miRNA-155 in RRMS and assess its relationship with inflammatory and anti-inflammatory mediators. The study included 60 MS patients and 30 healthy controls. Real-time quantitative polymerase chain reaction was utilized to detect miRNA-155, iNOS, and SMAD2, whereas ELISA was used to determine TNF-α, IFN-É£, TGF-ß, and IL-10 levels. There was no significant difference in miRNA-155, SMAD2, and iNOS expression in MS patients compared to control subjects. In addition, there was a statistically significant increase in TNF-α, INF-É£, and TGF-ß levels. IL-10 levels did not differ significantly between MS patients and healthy controls. There was a positive correlation between miRNA-155 and TNF-α (p < 0.000, r = 0.922), INF-É£ (p < 0.000, r = 0.81), and iNOS (p < 0.000, r = 0.916) and inverse correlation between miRNA-155 and IL-10 (p < 0.000, r = -0.928), TGF-ß (p < 0.000, r = -0.904) and SMAD2 (p < 0.000, r = -0.848). We conclude that expression of miRNA-155 in MS may modulate macrophage/microglia polarization by increasing the secretion of TNF-α, IFN-É£ & iNOS and decreasing anti-inflammatory mediators IL10 and TGF-ß.

Berberine protects against sepsis-related acute lung injury in rats via PPAR-γ signaling pathway upregulation and improvement at the cellular level: Functional, biochemical, and immunohistochemistry study.

This study aimed to assess the prophylactic effects of Berberine on experimentally induced lung sepsis and examine its effects on selected cytokines, genes, and protein expression besides the histopathological evaluation. Berberine significantly reduced the wet/dry lung ratio, the broncho-alveolar lavage fluid (BALF) protein, cells, neutrophils percentage, and cytokines levels. In addition, pretreatment with Berberine decreased the myeloperoxidase (MPO) and malondialdehyde (MDA) levels and decreased gene expression of nuclear factor kappa B (NF-κB), monocyte chemoattractant protein-1 (MCP-1), and the intracellular adhesion molecule 1 (ICAM-1) by RT-qPCR analysis, revealing Berberine's antioxidant and anti-inflammatory mode of action. Western blot analysis revealed increased peroxisome proliferator-activated receptor gamma (PPAR-γ) expression in the Berberine pretreated group compared to the cecal ligation and puncture (CLP) group, in which the histopathological examination evidenced this improvement. In conclusion, Berberine improved lung sepsis via its PPAR-γ mediated antioxidant and anti-inflammatory effects.

CT volumetry study of microfat graft survival from different donor sites in augmenting the enophthalmic socket.

PURPOSE: To evaluate autologous fat grafts harvested from the abdomen versus the thigh for treating the enophthalmic socket using CT volumetry. METHODS: A randomized prospective interventional study including 20 patients suffering from unilateral enophthalmic socket. Pre-operative clinical assessment included photographs, exophthalmometry reading as well as CT volumetry for volume deficit calculations and the harvesting site was randomly allocated (abdomen or thigh). All patients completed 6 months of follow-up. Exophthalmometry change and percentage of retained fat with the globe included and without it at follow-up were measured. RESULTS: Microfat graft survival showed no statistically significant correlation with sex, age, or donor site. Mean percentage of retained fat with globe and without it were 14.75% and 25.31%, respectively. Difficulty of extraction and degree of volume deficit correlated significantly with percentage of fat retained. Exophthalmometer change correlated significantly with percentage of fat retained. CONCLUSION: Autologous fat grafting is a safe and effective technique for volume augmentation of enophthalmic sockets regardless of its harvesting site. CT volumetry has an important role in accurately measuring the volume deficit as well as the postoperative results.

Long non-coding RNA maternally expressed gene 3, miR-125a-5p, CXCL13, and NF-kB in patients with immune thrombocytopenia.

The main aim of this study was to assess the expression level of circulating long non-coding RNA maternally expressed gene 3 (lncRNA-MEG3), microRNA (miR-125a-5P), the chemokine C-X-C motif ligand13 (CXCL13), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) in immune thrombocytopenia (ITP) cases and to study its relation to the disease severity and treatment response. This case-control study included 45 patients newly diagnosed as ITP and 45 healthy subjects. We assessed complete blood count, antinuclear antibodies, hepatitis B and C virus serology, lncRNA-MEG3, miR-125a-5P, and CXCL13 expression in serum by real-time PCR and NF-kb protein by ELISA. In ITP patients compared to control, lncRNA-MEG3 was significantly increased, and miRNA-125a-5P was decreased, and this was associated with higher CXCL13 and NF-kB levels (P < 0.001, for all).There was a significant negative correlation between platelet count and lncRNA-MEG3, CXCL13, and NF-kb, while a positive correlation with miR-125a-5p in ITP patients. Patients who responded to steroids had significantly higher miR-125a-5p (P = 0.016) and significantly lower lncRNA-MEG3 (P < 0.001), CXCL13 (P = 0.005), and NF-kb (p = 0.002). Based on the ROC curves, lncRNA-MEG3 displayed the highest area under the curve (AUC) in the identification of organ bleeding (AUC = 0.805), the response to steroids (AUC = 0.853), and the need for splenectomy (AUC = 0.75).

Potential impact of mesenchymal stem cells on nephrotoxicity induced by gamma irradiation and antiepileptic drugs cotherapy in rats.

The goal of this study was to assess the influence of bone marrow-derived mesenchymal stem cells (BM-MSCs) on the nephrotoxicity induced by fractionated doses of gamma irradiation (Rad) and the cotherapy of levetiracetam and oxcarbazepine in male rats. Adult rats were randomly divided into four groups. Group I: Control, Group II: antiepileptic drugs (AEDs), Group III: AEDs +Rad and Group IV: AEDs + Rad + MSCs. Rats treated with AEDs and exposed to fractionated doses of γ-irradiation displayed a discernible increase in serum urea, creatinine, kidney injury marker, kidney malondialdehyde, transforming growth factor beta (TGF-ß) and the relative expression of Smad3 along with a decrease in the relative expression of Smad7 and glutathione level. Alternatively, groups treated with BM-MSCs with AEDs and Rad showed a substantial modification in the majority of the evaluated parameters and looked to be successful in reducing the hazards of the combination therapy of AEDs and radiation. The reno-histopathological study supports the biochemical analysis. In conclusion, BM-MSCs exhibited therapeutic potential against nephrotoxicity induced by fractionated doses of γ-irradiation and AEDs. The outcome was brought about by the downregulation of the TGF-ß/Smad pathway. BM-MSCs might be suggested as a valuable therapeutic strategy to overcome kidney injury induced by gamma irradiation during AEDs cotherapy.

Nicorandil mitigates amiodarone-induced pulmonary toxicity and fibrosis in association with the inhibition of lung TGF-ß1/PI3K/Akt1-p/mTOR axis in rats.

The long-term side effect of the antiarrhythmic drug, amiodarone (AMIO), such as lung toxicity, remains a critical clinical issue. The previous knowledge denotes diverse antioxidant, anti-inflammatory, and antifibrotic properties of the anti-anginal drug, nicorandil (NI). Therefore, we aimed to investigate the possible protective effect of NI on pulmonary tissue remodelling following AMIO-induced lung toxicity. The included rats were assigned into four equal groups (n = 8): (1) control, (2) control group that received NI 10 mg kg-1  day-1 , (3) model group that received AMIO in a dose of 60 mg kg-1  day-1 , and (4) treated group (AMIO-NI) that were treated with AMIO plus NI as shown above. Drug administration continued for 10 weeks. AMIO resulted in deteriorated (p < 0.001) pulmonary functions accompanied by respiratory acidosis. AMIO showed an obvious histological injury score with intense collagen deposition, disturbed nitric oxide synthase enzymes (NOS/iNOS), and increased alpha smooth muscle actin expression. Furthermore, AMIO upregulated the transforming growth factor (TGF-ß1)/phosphoinositide-3 kinase (PI3K)-Akt1-p/mammalian target of rapamycin (mTOR) axis, which determined the possible mechanism of AMIO on pulmonary remodelling. NI treatment significantly (p < 0.001) prevented the AMIO-induced lung toxicity, as well as inhibited the TGF-ß1/PI3K/Akt1-p/mTOR axis in the lung tissue of rats. The results were confirmed by an in-vitro study. CONCLUSION: The current results revealed that NI was effective in preserving the lung structure and functions. Amelioration of the oxidative stress and modulation of TGF-ß1/PI3K/Akt1-p/mTOR have been achieved. This study suggests NI administration as a preventive therapy from the serious pulmonary fibrosis side effect of AMIO.

The Effect of Calcium hydroxide, Glass Ionomer and light cured resin modified calcium silicate on viability, proliferation and differentiation of stem cells from human exfoliated deciduous teeth.

BACKGROUND: Vital pulp therapy, based on the use of stem cells, has promising research and therapeutic applications in dentistry. It is essential to understand the direct effect of capping materials on the dental pulp stem cells of primary teeth, which contribute to the healing powers of the tooth. The aim of this study is to evaluate the effect of different capping materials (Calcium Hydroxide (DyCal®) - Glass Ionomer (Fuji IX®) and light-cured resin modified calcium silicate (TheraCal LC®)) on the viability, proliferation, and differentiation of stem cells from human exfoliated deciduous teeth (SHEDs). METHODS: SHEDs were isolated from extracted primary teeth, then divided into four groups and each of the capping materials were applied to the stem cells as follows: group I the controls, group II with Ca(OH)2, group III with the GIC, and group IV with the Theracal LC. For all groups assessment of viability and proliferation rate was done using the MTT cell proliferation assay. Also, Differentiation was evaluated by measuring the gene expression of Alkaline phosphatase enzyme activity (ALP) and Dentin matrix protein-1 (DMP1) through quantitative real-time PCR. Morphological assessment was conducted using Alizarin Red S staining. All evaluations were performed after 7 and 14 days of culture. RESULTS: TheraCal LC showed the highest values of proliferation, which was significant only compared to the control group after 2 weeks (p = 0.012). After one week, TheraCal LC showed the highest significant values of ALP and DMP1 compared to all other groups (p < 0.001). CONCLUSION: The three materials under study are biocompatible, maintain viability, and stimulate the proliferation and differentiation of SHEDs. However, TheraCal LC allows better proliferation of SHEDs than Dycal Ca(OH)2 and Fuji IX GIC.

Thymoquinone Potentiated the Anticancer Effect of Cisplatin on Hepatic Tumorigenesis by Modulating Tissue Oxidative Stress and Endoplasmic GRP78/CHOP Signaling.

Thymoquinone (TQ) combined with Cisplatin may augment its anticancer effect on hepatocellular carcinoma (HCC), through oxidative stress mitigation and endoplasmic reticulum (ER) protein modulation. Fifty adult male Wistar albino rats were assigned into five equal experimental groups (n = 10); 1) Control, 2) diethylnitrosamine/carbon tetrachloride-induced liver tumorigenesis model (HCC), 3) Cisplatin (2 mg.kg-1ip) treated rats, 4) Thymoquinone treated group (20 mg.kg-1oral), and 5) group treated with both drugs as in Groups 3 and 4. Treatment regimens started following model confirmation and continued for 4 weeks. In the HCC model, we detected elevated ER chaperone glucose-regulated protein-78 (GRP78) and reduced C/EBP-homologous protein (CHOP)-mediated apoptosis that was accompanied by the elevated alpha-fetoprotein (AFP) marker and deteriorated liver functions. Our original results indicated that Thymoquinone potentiated the pro-apoptotic effect of cisplatin by modulating GRP78/CHOP signaling. Cisplatin/TQ reduced the elevated GRP78 and induced CHOP-mediated apoptosis in the diseased liver tissues compared to the HCC and Cisplatin treated groups. Cisplatin/TQ combination normalized AFP levels and improved liver functions compared to both HCC and cisplatin groups alone. In conclusion, Thymoquinone enhanced the efficacy of Cisplatin in HCC treatment by modulating the GRP78/CHOP/caspase-3 pathway. Thymoquinone is recommended to achieve greater therapeutic benefits and reduce the cisplatin hepatotoxicity in HCC management.

Necrostatin-1 mitigates renal ischaemia-reperfusion injury - time dependent - via aborting the interacting protein kinase (RIPK-1)-induced inflammatory immune response.

The recently defined necroptosis process participates in the pathophysiology of several tissue injuries. Targeting the necroptosis mediator receptor-interacting protein kinase (RIPK1) by necrostatin-1 in different phases of ischaemia-reperfusion injury (IRI) may provide new insight into the protection against renal IRI. The rat groups included (n = 8 in each group): 1) Sham; 2) Renal IRI; 3) Necrostatin-1 treatment 20 min before ischaemia induction in a dose of 1.65 mg/kg/intravenous; 4) Necrostatin-1 injection just before reperfusion; 5) Necrostatin-1 injection 20 min after reperfusion establishment; and 6) drug injection at both the pre-ischaemia and at reperfusion time in the same dose. Timing dependent, necrostatin-1 diminished RIPK1 (p < 0.001), and aborted the necroptosis-induced renal cell injury. Necrostatin-1 decreased the renal chemokine (CXCL1), interleukin-6, intercellular adhesion molecule (ICAM-1), myeloperoxidase, and the nuclear factor (NFκB), concomitant with reduced inducible nitric oxide synthase (iNOS), inflammatory cell infiltration, and diminished cell death represented by apoptotic cell count and the BAX/Bcl2 protein ratio. In group 6, the cell injury was minimal and the renal functions (creatinine, BUN and creatinine clearance) were almost normalised. The inflammatory markers were diminished (p < 0.001) compared to the IRI group. The results were confirmed by histopathological examination. In conclusion, RIPK1 inhibition ameliorates the inflammatory immune response induced by renal IRI. The use of two doses was more beneficial as the pathophysiology of cell injury is characterised.

Histone deacetylase 1 in patients with alopecia areata and acne vulgaris: An epigenetic alteration.

BACKGROUND: Histone deacetylase 1 (HDAC1) belongs to class I histone deacetylases, which are zinc-dependent enzymes that remove the acetyl group from histones and other proteins providing epigenetic regulation of gene expression. It plays an important role in the hair follicle and epidermal homeostasis in addition to its immunomodulatory roles. Alopecia areata (AA) and acne vulgaris are common skin diseases in which epigenetic factors have been proposed. However, studies of epigenetic modifications in both diseases are quite limited. OBJECTIVE: This study aimed at elucidation of HDAC1 deregulation in AA and acne vulgaris. METHODS: A case-control study was conducted on 76 participants: 25 patients with patchy alopecia areata, 26 patients with acne vulgaris and 25 healthy controls. Blood samples were collected for the measurement of HDAC1 level by ELISA. RESULTS: A significant difference in the serum level of HDAC1 was found between the studied groups being highest in the AA group (P = 0.0001). It was significantly higher in the AA group than the acne vulgaris group (P = 0.0001). CONCLUSION: HDAC1 appears to be deregulated in patients with AA and acne vulgaris. This may suggest a potential therapeutic opportunity for HDAC inhibitors for the treatment of such diseases.

Study of the role of microRNAs 16 and 135a in patients with lifelong premature ejaculation receiving fluoxetine daily for 3 months: A prospective case control study.

We aimed to determine the level of miRNAs 16 and 135a in lifelong premature ejaculation (LPE) patients versus controls. Moreover, we evaluated the potential interplay between the studied miRNAs and fluoxetine in these patients after utilizing fluoxetine daily for 3 months. The study involved 60 consecutive LPE patients and 20 healthy age matched individuals as controls. The median miRNA16 was significantly higher in the controls (1.02) compared to the patients (0.31) (p < 0.001). Moreover, the median miRNA-135a was significantly higher in the controls compared to the patients 1.02 and 0.35, p < 0.001, respectively. In addition, the median pre-treatment miRNA16 in the responders was 0.29 that significantly increased to 0.66 (p < 0.001). The median pre-treatment miRNA-135a in the responders was 0.27 that significantly increased to 0.65 (p < 0.001). Furthermore, considering EXP(ß) for the odds ratio evaluation, with a 95% degree of confidence, a 1 fold increase in pre-treatment miRNA 135a fold change decreases the odds for being responsive to SSRI by 0.028. Meanwhile, there was non-significant association between fluoxetine responsiveness and age, pre-treatment miRNA 16, pre-treatment PEDT and pre-treatment IELT. The current study had shown that a lower pre-treatment miRNA 135a was significantly associated with response to fluoxetine.

Assessment of seminal cystatin C levels in infertile men with varicocele: A preliminary study.

Varicocele has been raised as a contributor to male infertility supported by the improvement of sperm parameters after varicocelectomy. Cystatin C (Cys C) has been linked to several cellular changes that are common in male infertility cases associated with varicocele such as apoptosis and autophagy. This preliminary study aimed to assess the seminal levels of Cys C in infertile oligoasthenoteratozoospermic (OAT) men associated with varicocele that have been shown to have spermatic vein vasodilation and active death pathway. Overall, 60 men were investigated being divided into two equivalent groups-infertile OAT men with varicocele who underwent varicocelectomy and healthy fertile men as a control group. These men were subjected to history taking, clinical examination, semen analysis and assessment of seminal Cys C pre and 6 months post-varicocelectomy. The results showed a significant increase of seminal Cys C in infertile OAT men with varicocele than the fertile control (55.57 ± 25.6 ng/ml versus 10.78 ± 1.88 ng/ml, p = .001). Seminal Cys C was a significantly decreased post-operative than its pre-operative level (34.69 ± 14.02 versus 55.57 ± 25.6 ng/ml, p = .01). These results show a potential role of Cys C in varicocele-induced infertility.

Salivary expression of lncRNA DQ786243 and IL-17 in oral lichen planus: case-control study.

BACKGROUND: A growing number of studies has investigated IL-17 in OLP. However, its exact role and interactions are not fully determined. In addition, the literature investigating its salivary expression is limited. The scarcity in the literature studying lncRNAs was noticed, particularly with regards to correlating them with cytokines in OLP. In the current study, the salivary expression of lncRNA DQ786243 and IL-17 was assessed among different forms of OLP. METHODS: The study included 52 participants in four equal groups: reticular OLP, erythematous OLP, ulcerative OLP, and control group. All eligible OLP patients underwent conventional oral examination, along with basic charting of their demographic data, pain intensity using a visual analogue scale, and clinical evaluation using the Thongprasom et al. scale. The salivary expression of lncRNA DQ786243 and IL-17 was evaluated for all participants using qRT-PCR. Unstimulated whole saliva samples were used. Data were analyzed for statistical significance. RESULTS: No statistically significant difference was observed when comparing the mean age and gender distribution of the studied groups. A statistically significant difference was detected when comparing pain and clinical scores in the three OLP forms. The highest expression of both salivary biomarkers was noticed in ulcerative OLP, followed by erythematous OLP and reticular OLP, then the controls, with a significant difference between the studied groups. Upon comparing the salivary expression of DQ786243 in ulcerative and erythematous OLP, no significant difference was detected. No significant difference was detected when comparing salivary expression of IL-17 in erythematous OLP to the other OLP forms. CONCLUSIONS: The salivary expression of lncRNA DQ786243 and IL-17 was upregulated in OLP compared to healthy individuals. Besides, their expression increased when the severity of OLP was at its highest level in ulcerative OLP. There was a positive correlation between DQ786243 and IL-17. Trial registration The protocol was registered at ClinicalTrials.gov (NCT04503824). The date of registration is 07/08/2020.

IκB kinase inhibition remodeled connexins, pannexin-1, and excitatory amino-acid transporters expressions to promote neuroprotection of galantamine and morphine.

Inflammatory pathway and disruption in glutamate homeostasis join at the level of the glia, resulting in various neurological disorders. In vitro studies have provided evidence that membrane proteins connexions (Cxs) are involved in glutamate release, meanwhile, excitatory amino-acid transporters (EAATs) are crucial for glutamate reuptake (clearance). Moreover, pannexin-1 (Panx-1) activation is more detrimental to neurons. Their expression patterns during inflammation and the impacts of IκB kinase (IKK) inhibition, morphine, and galantamine on the inflammatory-associated glutamate imbalance remain elusive. To investigate this, rats were injected with saline or lipopolysaccharide. Thereafter, vehicles, morphine, galantamine, and BAY-117082 were administered in different groups of animals. Subsequently, electroencephalography, enzyme-linked immunosorbent assay, western blot, and histopathological examinations were carried out and various indicators of inflammation and glutamate level were determined. Parallel analysis of Cxs, Panx-1, and EAAts in the brain was performed. Our findings strengthen the concept that unregulated expressions of Cxs, Panx-1, and EAATs contribute to glutamate accumulation and neuronal cell loss. Nuclear factor-kB (NF-κB) pathway can significantly contribute to glutamate homeostasis via modulating Cxs, Panx-1, and EAATs expressions. BAY-117082, via inhibition of IkK, promoted the anti-inflammatory effects of morphine as well as galantamine. We concluded that NF-κB is an important component of reshaping the expressions of Cxs, panx-1, and EAATs and the development of glutamate-induced neuronal degeneration.

Hydrogen sulfide and mesenchymal stem cells-extracted microvesicles attenuate LPS-induced Alzheimer's disease.

Both hydrogen sulfide (H2 S) and mesenchymal stem cells (MSCs) extracted microvesicles (MVs) are potent anti-inflammatory molecules. They play an essential role in lowering the production of tumor necrosis factor-alpha (TNF-α). The latter could strongly stimulate MiR-155 that contributes to neurodegeneration and Alzheimer's disease (AD). miR-155 could repress the expression of inositol 5-phosphatase-1 (SHIP-1) leading eventually to activation of Akt kinase and neurofibrillary development in AD. The current study was conducted to evaluate the role of miR-155 in a rat model of lipopolysaccharide (LPS)-induced AD and to investigate the effect of using MVs and H2 S that were given either separately or combined in regulating pro-inflammatory signaling. Thirty female Wistar albino rats aged 6 months to 1 year were equally divided into five groups; control group, LPS-induced AD group, LPS + MVs group, LPS + NaHS group, and LPS + MVs and NaHS group. The increased miR-155 level was associated with decreased SHIP-1 level and positively correlated with TNF-α. In addition, treatment with MVs and/or NaHS resulted in attenuation of inflammation, decreasing miR-155, pAkt levels, and downregulation of apoptosis along with improvement of the hippocampal and cortical histopathological alterations. LPS enhanced production of malondialdehyde (MDA) and reduced glutathione (GSH) levels indicating oxidative stress-induced neural damage, whereas MVs and NaHS could mitigate oxidative damage and accelerate antioxidant capacity via increasing catalase enzyme. In conclusion, downregulation of TNF-α, miR-155, and pAkt and increased SHIP-1 could improve the neuro-inflammatory state and cognitive function of LPS-induced Alzheimer's disease.

Investigating Helicobacter pylori-related pyloric hypomotility: functional, histological, and molecular alterations.

Multiple theories have been proposed describing the pathogenic mechanisms of Helicobacter pylori (H. pylori)-associated gastric motility disorders. We assessed ex vivo pyloric activity in H. pylori-infected rats, and tried to explore the associated ghrelin hormone alteration and pyloric fibrogenesis. In addition, miR-1 was assessed in pyloric tissue samples, being recently accused of having a role in smooth muscle dysfunction. Ninety adult male Wistar albino rats were assigned into nine groups: 1) control group, 2) sterile broth (vehicle group), 3) amoxicillin control, 4) omeperazole control, 5) clarithromycin control, 6) triple therapy control, 7) H. pylori- group, 8) H. pylori-clarithromycin group, and 9) H. pylori-triple therapy group. Urease enzyme activity was applied as an indicator of H. pylori infection. Ex vivo pyloric contractility was evaluated. Serum ghrelin was assessed, and histological tissue evaluation was performed. Besides, pyloric muscle miR-1 expression was measured. The immunological epithelial to mesenchymal transition (EMT) markers; transforming growth factor ß (TGFß), α-smooth muscle actin (α-SMA), and E-cadherin-3 were also evaluated. By H. pylori infection, a significant (P < 0.001) reduced pyloric contractility index was recorded. The miR-1 expression was decreased (P < 0.001) in the H. pylori-infected group, associated with reduced serum ghrelin, elevated TGFß, and α-SMA levels and reduced E-cadherin levels. Decreased miR-1 and disturbed molecular pattern were improved by treatment. In conclusion, H. pylori infection was associated with reduced miR-1, epithelial to mesenchymal transition, and pyloric hypomotility. The miR-1 may be a target for further studies to assess its possible involvement in H. pylori-associated pyloric dysfunction, which might help in the management of human H. pylori manifestations and complications.NEW & NOTEWORTHY This work is investigating functional, histopathological, and molecular changes underlying Helicobacter pylori hypomotility and is correlating these with miR-1, whose disturbance is supposed to be involved in smooth muscle dysfunction and cell proliferation according to literature. Epithelial to mesenchymal transition and reduced ghrelin hormone may contribute to H. pylori infection-associated hypomotility. H. pylori infection was associated with reduced pyloric miR-1 expression. Targeting miR-1 could be valuable in the clinical management of pyloric hypofunction.

Metformin impairs homing ability and efficacy of mesenchymal stem cells for cardiac repair in streptozotocin-induced diabetic cardiomyopathy in rats.

Bone marrow-derived mesenchymal stem cells (BM-MSCs) have demonstrated potential in treating diabetic cardiomyopathy. However, patients with diabetes are on multiple drugs and there is a lack of understanding of how transplanted stem cells would respond in presence of such drugs. Metformin is an AMP kinase (AMPK) activator, the widest used antidiabetic drug. In this study, we investigated the effect of metformin on the efficacy of stem cell therapy in a diabetic cardiomyopathy animal model using streptozotocin (STZ) in male Wistar rats. To comprehend the effect of metformin on the efficacy of BM-MSCs, we transplanted BM-MSCs (1 million cells/rat) with or without metformin. Our data demonstrate that transplantation of BM-MSCs prevented cardiac fibrosis and promoted angiogenesis in diabetic hearts. However, metformin supplementation downregulated BM-MSC-mediated cardioprotection. Interestingly, both BM-MSCs and metformin treatment individually improved cardiac function with no synergistic effect of metformin supplementation along with BM-MSCs. Investigating the mechanisms of loss of efficacy of BM-MSCs in the presence of metformin, we found that metformin treatment impairs homing of implanted BM-MSCs in the heart and leads to poor survival of transplanted cells. Furthermore, our data demonstrate that metformin-mediated activation of AMPK is responsible for poor homing and survival of BM-MSCs in the diabetic heart. Hence, the current study confirms that a conflict arises between metformin and BM-MSCs for treating diabetic cardiomyopathy. Approximately 10% of the world population is diabetic to which metformin is prescribed very commonly. Hence, future cell replacement therapies in combination with AMPK inhibitors may be more effective for patients with diabetes.NEW & NOTEWORTHY Metformin treatment reduces the efficacy of mesenchymal stem cell therapy for cardiac repair during diabetic cardiomyopathy. Stem cell therapy in diabetics may be more effective in combination with AMPK inhibitors.

Hypoxia-induced downregulation of cyclooxygenase 2 leads to the loss of immunoprivilege of allogeneic mesenchymal stem cells.

Allogeneic mesenchymal stem cells (MSCs) from young and healthy donors are reported to hold the potential to treat several immunological and degenerative disorders. However, recent data from animal studies and clinical trials demonstrate that immunogenicity and poor survival of transplanted MSCs impaired the efficacy of cells for regenerative applications. It is reported that initially immunoprivileged under in vitro conditions, MSCs are targeted by the host immune system after transplantation in the ischemic tissues in vivo. We performed in vitro (in MSCs) and in vivo (in the rat model of myocardial infarction [MI]) studies to elucidate the mechanisms responsible for the change in the immunophenotype of MSCs from immunoprivileged to immunogenic under ischemic conditions. We have recently reported that a soluble factor prostaglandin E2 (PGE2) preserves the immunoprivilege of allogeneic MSCs. In the current study, we found that PGE2 levels, which were elevated during normoxia, decreased in MSCs following exposure to hypoxia. Further, we found that proteasome-mediated degradation of cyclooxygenase-2 (COX2, rate-limiting enzyme in PGE2 biosynthesis) in hypoxic MSCs is responsible for PGE2 decrease and loss of immunoprivilege of MSCs. While investigating the mechanisms of COX2 degradation in hypoxic MSCs, we found that in normoxic MSCs, COP9 signalosome subunit 5 (CSN5) binds to COX2 and prevents its degradation by the proteasome. However, exposure to hypoxia leads to a decrease in CSN5 levels and its binding to COX2, rendering COX2 protein susceptible to proteasome-mediated degradation. This subsequently causes PGE2 downregulation and loss of immunoprivilege of MSCs. Maintaining COX2 levels in MSCs preserves immunoprivilege in vitro and improves the survival of transplanted MSCs in a rat model of MI. These data provide novel mechanistic evidence that PGE2 is downregulated in hypoxic MSCs which is responsible for the post-transplantation rejection of allogeneic MSCs. Therefore, our data suggest that the new strategies that target CSN5-COX2 signaling may improve survival and utility of transplanted allogeneic MSCs in the ischemic heart.

Hypoxia-induced increase in Sug1 leads to poor post-transplantation survival of allogeneic mesenchymal stem cells.

Allogeneic mesenchymal stem cells (MSCs) from young and healthy donors are immunoprivileged and have the potential to treat numerous degenerative diseases. However, recent reviews of clinical trials report poor long-term survival of transplanted cells in the recipient that turned down the enthusiasm regarding MSC therapies. Increasing evidence now confirm that though initially immunoprivileged, MSCs eventually become immunogenic after transplantation in the ischemic or hypoxic environment of diseased tissues and are rejected by the host immune system. We performed in vitro (in rat and human cells) and in vivo (in a rat model) investigations to understand the mechanisms of the immune switch in the phenotype of MSCs. The immunoprivilege of MSCs is preserved by the absence of cell surface immune antigen, major histocompatibility complex II (MHC-II) molecule. We found that the ATPase subunit of 19S proteasome "Sug1" regulates MHC-II biosynthesis in MSCs. Exposure to hypoxia upregulates Sug1 in MSCs and its binding to class II transactivator (CIITA), a coactivator of MHC-II transcription. Sug1 binding to CIITA in hypoxic MSCs promotes the acetylation and K63 ubiquitination of CIITA leading to its activation and translocation to the nucleus, and ultimately MHC-II upregulation. In both rat and human MSCs, knocking down Sug1 inactivated MHC-II and preserved immunoprivilege even following hypoxia. In a rat model of myocardial infarction, transplantation of Sug1-knockdown MSCs in ischemic heart preserved immunoprivilege and improved the survival of transplanted cells. Therefore, the current study provides novel mechanisms of post-transplantation loss of immunoprivilege of MSCs. This study may help in facilitating better planning for future clinical trials.

Remote liver injury following acute renal ischaemia-reperfusion: involvement of circulating exosomal miR-687 and regulation by thymoquinone.

NEW FINDINGS: What is the central question of this study? What is the role of circulating exosomal miR-687 in remote hepatic injury following renal ischaemia-reperfusion injury (IRI) and does thymoquinone have a modulatory impact? What is the main finding and its importance? Exosomal miR-687 was expressed in renal IRI, entered the circulation and was deposited in the liver. Liver exosomal miR-687 was correlated with liver inflammation and apoptosis. Thymoquinone aborted the renal production of exosomal miR-687 and its further circulation to the liver. ABSTRACT: The pathophysiology of remote hepatic injury following acute renal ischaemia-reperfusion injury (IRI) is of particular clinical interest. Secreted small non-coding microRNA (miRs) are thought to exist in exosome-encapsulated form. Thymoquinone (TQ) is the main bioactive ingredient of Nigella sativa and has several renoprotective actions. We expected exosomal miR-687 to be relevant as it could act as a humoral mediator, with possible modulation by TQ. Thirty adult male Wister albino rats were assigned to three groups (n = 10); (1) sham-operated, (2) renal ischaemia-reperfusion injury (IRI), and (3) renal IRI pre-treated with TQ 10 mg/kg/day i.v. (TQ-IRI) for 10 days in addition to a dose administered at reperfusion onset. Following 24 h of reperfusion, the IRI group showed renal tissue hypoxia-inducible factor upregulation (P < 0.001). Electron microscopy images of exosomes and analysis of miR-687 revealed elevated levels, which appeared in the circulation. Large amounts of exosomal miR-687 were transmitted to the liver tissue. In the IRI group, liver transaminases (alanine aminotransferase, aspartate aminotransferase) were markedly (P < 0.001) elevated. The hepatic tissue inflammatory markers (vascular cell adhesion molecule-1, myeloperoxidase, monocyte chemotactic protein-1 and nuclear factor-κB) were upregulated (P < 0.001) accompanied with elevated caspase-3. TQ suppressed (P < 0.001) the renal expression and release of exosomal miR-687 into the circulation and its further deposition in the liver tissue; consequently, TQ diminished (P < 0.001) liver tissue inflammation and cellular apoptosis. The results were confirmed by histological tissue assessment. In conclusion, exosomal miR-687 liberated from injured renal tissues into the circulation may be an important factor in inducing remote hepatic injury. Exosomal miR-687 inhibition by TQ protected both renal and hepatic tissues from injury.