Inhibition of dipeptidyl peptidase IV (DPP IV) is one of the mechanisms explaining the hypoglycemic effect of berberine

Almasri, Ihab M.; Mohammad, Mohammad K.; Taha, Mutasem O.

doi:10.1080/14756360802610761

Cited by 127 publications

(64 citation statements)

References 44 publications

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“…The reaction was initiated by the addition of DPP-4 (1 U/ml, Calbiochem; Merck Millipore, Nottingham, UK), and plates were incubated at 37°C with gentle agitation for 1 h, after which 100 μl of 3 mM acetic acid was added to terminate reactions. Berberine (13 mM; Sigma-Aldrich Co.), a previously reported plant compound with DPP-4 inhibitory activity (Al-Masri et al 2009), was used in each experiment as a positive control. Data were expressed as percentages (mean ± SEM) and compared with controls by means of one-way ANOVA using the Dunnett post hoc test.…”

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confidence: 99%

Lactobacilli possess inhibitory activity against dipeptidyl peptidase-4 (DPP-4)

et al. 2015

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Dipeptidyl peptidase-4 (DPP-4) plays an important role in the enzymatic inactivation of incretin hormones. In this context, drugs that inhibit DPP-4 have been developed and clinically approved as therapies for type 2 diabetes. As the primary substrates of DPP-4 are produced in the intestinal lining, we investigated whether lactobacilli colonizing the gut could inhibit this enzyme. Fifteen Lactobacillus strains (Lb 1-15) from human infant faecal samples were isolated, identified, extracted and screened for inhibitory activity against DPP-4. Activity was compared against Lactobacillus reference strains (Ref 1-7), a Gram-positive control (Ctrl 1) and two Gram-negative controls (Ctrl 2-3). A range of DPP-4 inhibitory activity was observed (10-32 %; p<0.05-0.001). Strains of L. plantarum (12-25 %) and L. fermentum (14 %) had significant inhibitory activity. However, we noted that Escherichia coli (Ctrl 2) and Salmonella Typhimurium (Ctrl 3) had the greatest inhibitory activity (30-32 %). Contrastingly, some isolates (Lb 12-15) and reference cultures (Ref 1-4), instead of inhibiting DPP-4, actually enhanced it, perhaps indicating the presence of X-prolyldipeptidyl-amino-peptidase (PepX). This provides a future rationale for using probiotic bacteria or their components for management of type 2 diabetes via DPP-4 inhibition.

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confidence: 99%

Lactobacilli possess inhibitory activity against dipeptidyl peptidase-4 (DPP-4)

et al. 2015

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“…The DPP-IV inhibitory activity of seaweed extract was determined according to the modified method of Al-Masri et al (2009). Standard diprotin A (Sigma, St Louis, MO, USA) was diluted to various concentrations (0.2, 0.4, 0.8, 1.6, 3.2 and 6.4 μg/ml) using Tris-HCl buffer (50 mM, pH 7.5), the final volume was made up to 35 μl, and 15 μl of DPP-IV enzyme (Sigma, St Louis, MO, USA) was added to the mixture.…”

Section: Dpph Free Radical Scavenging Activitymentioning

confidence: 99%

“…These, in turn, have a direct effect on pancreatic cells by the secretion of insulin from the β-cells and the suppression of glucagon release from the α-cells. GLP-1 can also act at peripheral tissues to improve insulin utilization and GIP is also involved in glucose metabolism via insulin secretion (Al-Masri et al 2009). Both of these incretin hormones have very short half-lives because of their rapid degradation by DPP-IV.…”

Section: Introductionmentioning

confidence: 99%

Antidiabetic potential of marine algae by inhibiting key metabolic enzymes

Unnikrishnan

Suthindhiran

Jayasri

2015

Frontiers in Life Science

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Two edible seaweeds, Sargassum polycystum and Sargassum wightii, were investigated for their antidiabetic potential using in vitro enzyme inhibitory assays. Among the various extracts, petroleum ether and ethyl acetate extracts of S. wightii showed significant inhibitory effects against α-amylase (IC 50 378.3 μg/ml) and α-glucosidase (IC 50 314.8 μg/ml). Methanol extract of S. wightii showed the highest inhibition against dipeptidyl peptidase-IV (DPP-IV) (IC 50 38.27 μg/ml) and moderate antioxidant activity was observed in acetone extract of S. wightii (44%). Similarly, ethyl acetate extract of S. polycystum showed the highest inhibition against α-amylase (IC 50 438.5 μg/ml) and methanol extract of S. polycystum showed maximum inhibition against α-glucosidase (IC 50 289.7 μg/ml) and DPP-IV (36.94 μg/ml). The antioxidant activity was poor (22%). The extracts were investigated for in vitro cytotoxicity, DNA fragmentation in macrophages and haemolytic activity against erythrocytes, but no notable toxicity was observed with any of the tested extracts. Gas chromatography-mass spectrometry revealed the presence of the antidiabetic compound fucosterol and other major bioactive compounds, giving an insight into the antidiabetic and antioxidant properties of these algae. This study reveals the possible mechanisms of antidiabetic action in vitro, and these two seaweeds may also have an antidiabetic action in vivo.

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“…The mechanisms of action include inhibition of aldose reductase inducing glycolysis, preventing insulin resistance through increasing insulin receptor expression and acting like incretins. A new study suggested berberine may overcome insulin resistance via modulating key molecules in insulin signaling pathway, leading to increased glucose uptake in insulin-resistant cells [10,11]. Berberine seems to inhibit human DPP-4 as well as the prodiabetic target human protein tyrosine phosphatase 1B (h-PTP 1B), which explain at least some of its antihyperglycemic activities.…”

Section: Berberinementioning

confidence: 98%