Incretins and microRNAs: Interactions and physiological relevance

MicroRNAs (miRNA) are one class of the small regulatory RNAs that can impact the expression of numerous genes including incretin hormones and their G protein-coupled receptors. Incretin peptides, including GLP-1, GLP-2, and GIP, are released from the gastrointestinal tract and have an crucial role in the glucose hemostasis and pancreatic beta-cell function. These hormones and their analogs with a longer half-life, glucagon like peptide-1 receptor agonists (GLP1RA), modify the expression of miRNAs. Dipeptidyl peptidase IV (DPP-4) is an enzyme that degrades the incretin hormones and is inactivated by DPP-4 inhibitors, which are a class of compounds used in the management of type 2 diabetes. DPP-4 inhibitors may also increase or reduce the expression of miRNAs. In this review, we describe the possible interactions between miRNAs and incretin hormones and the relevance of such interactions to physiological processes and diseases

Evaluation of antibacterial activity of peptide fractions derived from Iranian scorpion Hemiscorpius lepturus

Background and aim: Continuous appearance of antibiotic resistance bacteria can cause significant complications and mortality. In this regard, tracing for new antimicrobial agents is of great significance. During the past decades, many studies have documented isolation of Antimicrobial Peptides (AMPs) from different sources. These peptides which are responsible for hinnate immunity were purified from human, vertebrates, invertebrates, insects, venomous animals, and plants. This study aimed to extract antibacterial peptides from Iranian scorpion Hemiscorpius lepturus. Material and Methods: Venom was obtained by electric stimulation and its quality examined by protein electrophoresis. The venom peptides were purified using Gel filtration chromatography and subsequently with Reverse Phase- High Performance Liquid Chromatography (RP-HPLC). The peptide fractions were evaluated for antibacterial activity against Pseudomonas aeruginosa ATCC 27853. Inhibitory activity was determined by disk diffusion method. Result: Seven protein fractions were obtained from Sephadex-G50, among them only two fractions had peptides with less than 10 kDa. One FPLC purified fraction had anti-pseudomonas activity by disk diffusion method and was selected for further purification. Four major fractions were obtained by RP-HPLC ranging from 4 to 7 kDa. Subsequent tests showed that two fractions had bactericidal activity against pseudomonas. Conclusion: Natural compounds like antimicrobial peptides derived from venomous animals could be an effective solution to deal with multidrug-resistant pathogens. The results demonstrated that two peptide fractions of the scorpion venom had bactericidal activity against pseudomonas. This is the first report for isolation of antibacterial peptides from the Iranian scorpion Hemiscorpius lepturus

The effects of curcumin on brain-derived neurotrophic factor expression in neurodegenerative disorders

Brain-Derived Neurotrophic Factor (BDNF) is a crucial molecule implicated in plastic modifications related to learning and memory. The expression of BDNF is highly regulated, which can lead to significant variability in BDNF levels in healthy subjects. Changes in BDNF expression might be associated with neuropsychiatric diseases, particularly in structures important for memory processes, including the hippocampus and parahippocampal areas. Curcumin is a natural polyphenolic compound that has great potential for the prevention and treatment of age-related disorders by regulating and activating the expression of neural protective proteins such as BDNF. This review discusses and analyzes the available scientific literature on the effects of curcumin on BDNF production and function in both in vitro and in vivo models of disease.</p

Antioxidant Effects of Statins by Modulating Nrf2 and Nrf2/HO-1 Signaling in Different Diseases

Statins are competitive inhibitors of hydroxymethylglutaryl-CoA (HMG-CoA) reductase and have been used to treat elevated low-density lipoprotein cholesterol (LDL-C) for almost four decades. Antioxidant and anti-inflammatory properties which are independent of the lipid-lowering effects of statins, i.e., their pleiotropic effects, might be beneficial in the prevention or treatment of many diseases. This review discusses the antioxidant effects of statins achieved by modulating the nuclear factor erythroid 2 related factor 2/ heme oxygenase-1 (Nrf2/HO-1) pathway in different organs and diseases. Nrf2 and other proteins involved in the Nrf2/HO-1 signaling pathway have a crucial role in cellular responses to oxidative stress, which is a risk factor for ASCVD. Statins can significantly increase the DNA-binding activity of Nrf2 and induce the expression of its target genes, such as HO-1 and glutathione peroxidase) GPx, (thus protecting the cells against oxidative stress. Antioxidant and anti-inflammatory properties of statins, which are independent of their lipid-lowering effects, could be partly explained by the modulation of the Nrf2/HO-1 pathway

Impact of Intravenous Trehalose Administration in Patients with Niemann–Pick Disease Types A and B

Background and aims: Niemann-Pick disease (NPD) types A (NPA) and B (NPB) are caused by deficiency of the acid sphingomyelinase enzyme, which is encoded by the SMPD1 gene, resulting in progressive pathogenic accumulation of lipids in tissues. Trehalose has been suggested as an autophagy inducer with therapeutic neuroprotective effects. We performed a single-arm, open-label pilot study to assess the potential efficacy of trehalose treatment in patients with NPA and NPB patients. ------ Methods: Five patients with NPD type A and B were enrolled in an open-label, single-arm clinical trial. Trehalose was administrated intravenously (IV) (15 g/week) for three months. The efficacy of trehalose in the management of clinical symptoms was evaluated in patients by assessing the quality of life, serum biomarkers, and high-resolution computed tomography (HRCT) of the lungs at the baseline and end of the interventional trial (day 0 and week 12). ----- Results: The mean of TNO-AZL Preschool children Quality of Life (TAPQOL) scores increased in all patients after intervention at W12 compared to the baseline W0, although the difference was not statistically significant. The serum levels of lyso-SM-509 and lyso-SM were decreased in three and four patients out of five, respectively, compared with baseline. Elevated ALT and AST levels were decreased in all patients after 12 weeks of treatment; however, changes were not statistically significant. Pro-oxidant antioxidant balance (PAB) was also decreased and glutathione peroxidase (GPX) activity was increased in serum of patients at the end of the study. Imaging studies of spleen and lung HRCT showed improvement of symptoms in two patients. ----- Conclusions: Positive trends in health-related quality of life (HRQoL), serum biomarkers, and organomegaly were observed after 3 months of treatment with trehalose in patients with NPA and NPB. Although not statistically significant, due to the small number of patients enrolled, these results are encouraging and should be further explored

Effects of Trehalose Administration in Patients with Mucopolysaccharidosis Type III.

Mucopolysaccharidosis type III (MPS III) is a rare autosomal recessive lysosomal storage disease (LSD) caused by a deficiency of lysosomal enzymes required for the catabolism of glycosaminoglycans (GAGs), mainly in the central nervous system. Trehalose has been proposed as a potential therapeutic agent to attenuate neuropathology in MPS III. We conducted a single-arm, open-label study to evaluate the efficacy of trehalose treatment in patients with MPS IIIA and MPS IIIB. Five patients with MPS III were enrolled. Trehalose was administrated intravenously (15 g/week) for 12 weeks. Health-related quality of life and cognitive function, serum biomarkers, liver, spleen, and lung imaging were assessed to evaluate trehalose efficacy at baseline and trial end (week 12). TNO-AZL Preschool children Quality of Life (TAPQOL) scores increased in all patients, and the mean scores for quality of life were increased after the intervention. Serum GAG levels were reduced in all treated patients (however, the differences were not statistically significant). Alanine aminotransferase (ALT) levels were reduced in all patients post-treatment (p=0.0039). The mean levels of aspartate transaminase (AST) were also decreased after 12 weeks of treatment with Trehalose. Decreased serum pro-oxidant-antioxidant balance and increased GPX activity were observed at the end of the study. Decreases in mean splenic length were observed, whereas the liver volume did not change. Improvements in health-related quality of life and serum biomarkers (GAGs, liver aminotransferase levels, antioxidant status), as well as liver and spleen size, were found following 3 months of trehalose administration in patients with MPS IIIA and MPS IIIB

The effects of oral trehalose on glycaemia, inflammation, and quality of life in patients with type 2 diabetes: a pilot randomized controlled trial

Introduction: Trehalose is a naturally occurring disaccharide of 2 glucose molecules, which has been suggested as a potential therapeutic agent to reduce blood glucose and ameliorate diabetes-related complications in type 2 diabetes (T2D). This study aimed to determine the efficacy of medium-term trehalose treatment in patients with T2D. Material and methods: A double-blind, randomized, placebo-controlled trial in 40 patients with T2D was undertaken; 20 ingested trehalose 3.3 g/day and 20 placebo (sucrose), for 3 months. Parameters of glycaemic indices, high-sensitivity C-reactive protein (CRP), mood status, and quality of life were measured. Results: CRP was significantly lower with trehalose treatment (-0.62 ±0.3 mg/l, p = 0.02); however, no differences in glycaemic indices of fasting blood glucose (FBG) (-7.1 ±10.7 mg/dl, p = 0.15), glycated hemoglobin (HbA1c) (-0.1 ±0.4%, p = 0.73), insulin (0.73 ±0.8 μU/ml, p = 0.39), or insulin resistance (HOMA-IR) (0.19 ±0.33, p = 0.56) were seen between groups after 12 weeks. Depression and stress scores were lower with trehalose compared to the placebo group (p = 0.02 and p = 0.05, respectively), whilst the quality-of-life score was higher with trehalose compared to placebo (p = 0.03) at the end of study. Between-group differences in these indices did not reach statistical significance (-2.36 ±1.20, -2.21 ±1.39 and 3.00 ±1.76 for depression, stress, and quality-of-life score, respectively) (p > 0.05). The pro-oxidant antioxidant balance (PAB) did not differ between groups (-4.6 ±12.8, p = 0.72). Conclusions: 12 weeks of treatment with 3.3 g/day of oral trehalose significantly improves CRP as a marker of inflammation, with potential favourable effects on quality of life, depression, and stress levels, but overall glycaemic control and pro-oxidant-antioxidant balance were unaltered during this time frame.</p

The effects of oral trehalose on glycaemia, inflammation, and quality of life in patients with type 2 diabetes: a pilot randomized controlled trial

Introduction: Trehalose is a naturally occurring disaccharide of 2 glucose molecules, which has been suggested as a potential therapeutic agent to reduce blood glucose and ameliorate diabetes-related complications in type 2 diabetes (T2D). This study aimed to determine the efficacy of medium-term trehalose treatment in patients with T2D. Material and methods: A double-blind, randomized, placebo-controlled trial in 40 patients with T2D was undertaken; 20 ingested trehalose 3.3 g/day and 20 placebo (sucrose), for 3 months. Parameters of glycaemic indices, high-sensitivity C-reactive protein (CRP), mood status, and quality of life were measured. Results: CRP was significantly lower with trehalose treatment (-0.62 ±0.3 mg/l, p = 0.02); however, no differences in glycaemic indices of fasting blood glucose (FBG) (-7.1 ±10.7 mg/dl, p = 0.15), glycated hemoglobin (HbA1c) (-0.1 ±0.4%, p = 0.73), insulin (0.73 ±0.8 μU/ml, p = 0.39), or insulin resistance (HOMA-IR) (0.19 ±0.33, p = 0.56) were seen between groups after 12 weeks. Depression and stress scores were lower with trehalose compared to the placebo group (p = 0.02 and p = 0.05, respectively), whilst the quality-of-life score was higher with trehalose compared to placebo (p = 0.03) at the end of study. Between-group differences in these indices did not reach statistical significance (-2.36 ±1.20, -2.21 ±1.39 and 3.00 ±1.76 for depression, stress, and quality-of-life score, respectively) (p > 0.05). The pro-oxidant antioxidant balance (PAB) did not differ between groups (-4.6 ±12.8, p = 0.72). Conclusions: 12 weeks of treatment with 3.3 g/day of oral trehalose significantly improves CRP as a marker of inflammation, with potential favourable effects on quality of life, depression, and stress levels, but overall glycaemic control and pro-oxidant-antioxidant balance were unaltered during this time frame.</p