In vitro comparison of whey protein isolate and hydrolysate for their effect on glucose homeostasis markers.

Research on new strategies to regulate glucose homeostasis to prevent or manage type 2 diabetes is a critical challenge. Several studies have shown that protein-rich diets could improve glucose homeostasis. Whey protein hydrolysis allows the release of amino acids and bioactive peptides, which exert numerous well-documented bioactivities. This study evaluates and compares the hypoglycemic potential of a whey protein hydrolysate and a whey protein isolate after static in vitro simulated gastrointestinal digestion (SGID) using the INFOGEST protocol. The peptide molecular mass distributions of the digested samples were evaluated by size exclusion chromatography and show that after digestion, the whey hydrolysate is significantly more hydrolyzed. After SGID, the whey protein hydrolysate induces a significative greater secretion of GLP-1 after two hours of contact with the enteroendocrine STC-1 cell line than the whey protein after isolation. In addition, the digested whey hydrolysate increases preproglucagon (GCG) and pro-convertase-1 (PCSK1) expression. The digested hydrolysate also inhibits the DPP-IV activity after an intestinal barrier passage challenge using a Caco-2/HT29-MTX mixed-cell model. Our results highlight that the prehydrolysis of whey proteins modify the intestinal peptidome, leading to a potentially greater hypoglycemic effect. This study confirms the previously observed in vitro hypoglycemic effect of this hydrolysate and evidences the beneficial impact of the industrial hydrolysis process.

Genotype-Phenotype Relationship in Patients and Relatives with SHOX Region Anomalies in the French Population.

BACKGROUND: The aim of our study was to describe a large population with anomalies involving the SHOX region, responsible for idiopathic short stature and Léri-Weill dyschondrosteosis (LWD), and to identify a possible genotype/phenotype correlation. METHODS: We performed a retrospective multicenter study on French subjects with a SHOX region anomaly diagnosed by multiplex ligation-dependent probe amplification or Sanger sequencing. Phenotypes were collected in each of the 7 genetic laboratories practicing this technique for SHOX analysis. RESULTS: Among 205 index cases and 100 related cases, 91.3% had LWD. For index cases, median age at evaluation was 11.7 (9.0; 15.9) years and mean height standard deviation score was -2.3 ± 1.1. A deletion of either SHOX or PAR1 or both was found in 74% of patients. Duplications and point mutations/indels affected 8 and 18% of the population, respectively. Genotype-phenotype correlation showed that deletions were more frequently associated with Madelung deformity and mesomelic shortening in girls, as well as with presence of radiologic anomalies, than duplications. CONCLUSIONS: Our results highlight genotype-phenotype relationships in the French population with a SHOX defect and provide new information showing that clinical expression is milder in cases of duplication compared to deletions.

CTLA-4 regulates the requirement for cytokine-induced signals in T(H)2 lineage commitment.

The relative importance of the cytokine milieu versus cytolytic T lymphocyte-associated antigen 4 (CTLA-4) and T cell receptor signal strength on T cell differentiation remains unclear. Here we have generated mice deficient for signal transducer and activator of transcription 6 (STAT6) and CTLA-4 to determine the role of CTLA-4 in cytokine-driven T cell differentiation. CTLA-4-deficient T cells bypass the need for STAT6 in the differentiation of T helper type 2 (T(H)2) cells. T(H)2 differentiation of cells deficient for both STAT6 and CTLA-4 is accompanied by induction of GATA-3 and the migration of T(H)2 cells to peripheral tissues. CTLA-4 deficiency also affects the balance of the nuclear factors NFATc1 and NFATc2, and enhances activation of NF-kappaB. These results suggest that CTLA-4 has a critical role in T cell differentiation and that STAT6-dependent T(H)2 lineage commitment and stabilization can be bypassed by increasing the strength of signaling through the T cell receptor.

Modified anti-CD3 therapy in psoriatic arthritis: a phase I/II clinical trial.

OBJECTIVE: Treatment of autoimmune diseases with therapies that tolerize pathogenic lymphocytes may obviate the need for longterm global immunosuppression. In vitro, non-Fc receptor binding derivatives of anti-murine CD3 monoclonal antibodies tolerize type 1 T cells and stimulate type 2 T cells. Recently, a humanized non-FcR binding derivative of the anti-human CD3 Mab OKT3, huOKT3gamma1(ala-ala), has been described. We hypothesized that this Mab may be safe and efficacious in the treatment of type 1 T lymphocyte mediated chronic autoimmune diseases such as psoriatic arthritis (PsA). METHODS: In a Phase I/II trial, 7 patients with PsA were treated with escalating daily doses of huOKT3gamma1(ala-ala) for 12 to 14 days. Number of tender and swollen joints and a visual analog pain scale were used to rate disease activity at entry and Day 30 and Day 90 after treatment. RESULTS: At Day 30, 6 of 7 patients had > or = 75% improvement in the number of inflamed joints and an average 63% improvement on the patient pain scale. Two of 6 responders had sustained improvement at Day 90. No patient treated with an initial dose < or = 1 mg had significant side effects, nor did they have detectable increases in serum cytokines. One patient treated with 4 mg without escalation developed mild cytokine release symptoms associated with elevation of interleukin 10. Transient T cell depletion occurred following treatment with the maximum dose of 4 mg, which resolved by Day 30. Antiidiotypic antibodies developed in 2 patients; however, there was no concurrent decrease in efficacy. CONCLUSION: These data indicate that huOKT3gamma1(ala-ala) may be useful in treating PsA.