Late-Stage Functionalization with Cysteine Staples Generates Potent and Selective Melanocortin Receptor-1 Agonists.

In this work, cysteine staples were used as a late-stage functionalization strategy to diversify peptides and build conjugates targeting the melanocortin G-protein-coupled receptors [melanocortin receptor-1 (MC1R) and MC3R-MC5R]. Monocyclic and bicyclic agonists based on sunflower trypsin inhibitor-1 were used to generate a selection of stapled peptides that were evaluated for binding (pKi) and functional activation (pEC50) of the melanocortin receptor subtypes. Stapled peptides generally had improved activity, with aromatic stapled peptides yielding selective MC1R agonists, including a xylene-stapled peptide (2) with an EC50 of 1.9 nM for MC1R and >150-fold selectivity for MC3R and MC4R. Selected stapled peptides were further functionalized with linkers and payloads, generating a series of conjugated peptides with potent MC1R activity, including one pyridazine-functionalized peptide (21) with picomolar activity at MC1R (Ki 58 pM; EC50 < 9 pM). This work demonstrates that staples can be used as modular synthetic tools to tune potency and selectivity in peptide-based drug design.

The effect of Lactiplantibacillus plantarum 299v together with a low dose of iron on iron status in healthy pregnant women: A randomized clinical trial.

INTRODUCTION: Iron deficiency during pregnancy is a global health problem and is associated with adverse pregnancy outcomes. The aim of this randomized, double-blind, placebo-controlled study was to evaluate the effect of Lactiplantibacillus plantarum 299v (Lp299v, 1010 colony forming units), 4.2 mg iron, 12 mg ascorbic acid and 30 µg folic acid (Lp) on iron status in healthy, non-anemic, pregnant Swedish women. MATERIAL AND METHODS: A total of 326 women were randomized to receive Lp (n = 161) or placebo (n = 165) twice daily from gestational week 10-12 until end of pregnancy or until the potential start of iron therapy. The primary endpoint was serum ferritin at week 28. RESULTS: Intake of Lp attenuated the decrease in serum ferritin from baseline to week 28 (p = 0.003) and week 35 (p Ë‚ 0.001) and resulted in reduced prevalence of iron deficiency (59% vs 78%, p = 0.017) and iron deficiency anemia (7.4% vs 21%, p = 0.023) at week 35. Intake of Lp also resulted in beneficial effects on the soluble transferrin receptor (p = 0.011) and total body iron (p Ë‚ 0.001) at week 35. Gestational length and birthweight were comparable between groups. The proportion of women reporting adverse events during the study was comparable between groups. CONCLUSIONS: Intake of Lp from early pregnancy was safe, attenuated the loss of iron stores and improved iron status in healthy pregnant women.

Ex vivo anti-inflammatory effects of probiotics for periodontal health.

Background: Probiotic bacteria with anti-inflammatory properties have the potential to be of therapeutic benefit in gingivitis. Objective: To evaluate the effects of potential probiotic strains on inflammatory mediators involved in early gingivitis using an ex vivo inflammation model. Methods: Strains were screened in viable and attenuated forms for effects on bacterial lipopolysaccharide (LPS)-stimulated release of interleukins (IL)-1ß, -6 and -8, tumor necrosis factor-α, prostaglandin E2 and 8-isoprostane from human primary monocytes, and then, if anti-inflammatory effects were shown, on IL-1ß-stimulated release of inflammatory mediators from primary gingival fibroblasts. Lead strains were evaluated for optimal dosing, batch-to-batch variation and functional consistency in toothpaste. Results: Twenty-one of 73 strains showed anti-inflammatory effects in monocytes; of which, seven showed effects in both viable and attenuated forms. Seven of 14 strains showed effects in fibroblasts. Strains Lactobacillus paracasei LPc-G110(SYBIO-15) and Lactobacillus plantarum GOS42(SYBIO-41) induced statistically significant dose-dependent reductions in the release of multiple inflammatory mediators from monocytes, which were consistent across batches. Viable L. paracasei LPc-G110 tooth paste significantly reduced IL-6, IL-8 and prostaglandin E2 release from monocytes versus placebo. Conclusion: Strains L. paracasei LPc-G110 and L. plantarum GOS42 have potential for use as probiotics in oral care products to reduce gingival inflammation.

Partial agonist activity of R3(BΔ23-27)R/I5 at RXFP3--investigation of in vivo and in vitro pharmacology.

Relaxin family peptide receptor 3 (RXFP3) is a G-protein coupled receptor mainly expressed in the brain and involved in appetite regulation. Previous studies in lean Wistar rats during the light phase have shown that the chimeric peptide R3(BΔ23-27)R/I5 suppresses food intake stimulated by an RXFP3 agonist, but has no effect on food intake when administered alone. We wanted to further investigate if R3(BΔ23-27)R/I5 on its own is able to antagonize the basal tone of the relaxin-3/RXFP3 system and therefore characterized the pharmacology of R3(BΔ23-27)R/I5 in vivo and in vitro. R3(BΔ23-27)R/I5 was intracerebroventricularly (ICV) injected in diet induced obese (DIO) Wistar rats and food intake was automatically measured during the dark phase when feeding drive is high. In our hands, R3(BΔ23-27)R/I5 alone did not have a significant effect on food intake during 24h following administration. Consistent with previous results, relaxin-3 stimulated food intake in satiated lean rats. R3(BΔ23-27)R/I5 was characterized in vitro using [(35)S]-GTPγS binding and cAMP assays, both assessing Gαi-protein mediated signalling, and dynamic mass redistribution (DMR) assays capturing the integrated cell response. R3(BΔ23-27)R/I5 showed partial agonist activity in all three functional assays. Thus, since R3(BΔ23-27)R/I5 displays partial RXFP3 agonist properties in vitro, further in vivo studies including additional tool compounds are needed to address if antagonizing relaxin-3/RXFP3 basal tone is a therapeutically relevant mechanism to regulate food intake and body weight.