Journal: Investigative Ophthalmology & Visual Science

Article Title: Dipeptidyl Peptidase 4, a Novel Adipokine, Impairs Retinal Microcirculation in Patients With Type 2 Diabetes Mellitus

doi: 10.1167/iovs.66.14.4

Figure Lengend Snippet: Effect of DPP4 intraluminal incubation on the BK-induced vasodilation of the retinal arterioles ( A ). The dose-dependent effect of DPP4 in response to BK is examined before (control, n = 16), and after intraluminal incubation with 100 ng/mL ( n = 4), 400 ng/mL ( n = 4), or 1 µg/mL ( n = 8) DPP4 for 3 hours ( B ). The time-course effect of DPP4 in response to BK is examined before (control), and after intraluminal incubation with 1 µg/mL DPP4 for 1, 2, and 3 hours ( n = 8). * P < 0.05 versus control.

Article Snippet: Human recombinant DPP4 was purchased from R&D Systems, and DPP4 inhibitor teneligliptin was obtained from Mitsubishi Tanabe Pharma Co., Ltd. (Osaka, Japan).

Techniques: Incubation, Control

Journal: Investigative Ophthalmology & Visual Science

Article Title: Dipeptidyl Peptidase 4, a Novel Adipokine, Impairs Retinal Microcirculation in Patients With Type 2 Diabetes Mellitus

doi: 10.1167/iovs.66.14.4

Figure Lengend Snippet: Effect of coadministration of DPP4 with superoxide scavenger, NADPH oxidase inhibitor, xanthine oxidase inhibitor, or DPP4 inhibitor ( A ). The dilation of the retinal arterioles to BK is examined before (control, n = 14) and after intraluminal incubation with 1 µg/mL DPP4 plus the superoxide anion scavenger TEMPOL (1 mM; n = 5), the NADPH oxidase inhibitor apocynin (100 µM; n = 4), or the xanthine oxidase inhibitor allopurinol (10 µM; n = 5) ( B ). Dilation of the retinal arterioles in response to BK is examined before (control, n = 5) and after intraluminal incubation with 1 µM plus the DPP4 inhibitor teneligliptin (0.5 µM; n = 5). * P < 0.05 versus control. † P < 0.05 versus DPP4 alone.

Article Snippet: Human recombinant DPP4 was purchased from R&D Systems, and DPP4 inhibitor teneligliptin was obtained from Mitsubishi Tanabe Pharma Co., Ltd. (Osaka, Japan).

Techniques: Control, Incubation

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: DPP4 − KMSCs exhibit higher adipogenic potential in vitro. A–D) Keloid tissues were collected, minced, and seeded to isolate and culture keloid‐derived fibroblasts (A). The isolated fibroblasts were then differentiated toward adipogenic (B), osteogenic (C), and chondrogenic fates (D). E) Surface marker expressions were analyzed using flow cytometry. F) Keloid‐derived DPP4 + and DPP4 − fibroblasts were sorted via fluorescence‐activated cell sorting. G) RT‐qPCR was performed to evaluate the mRNA level of OCT4 , MYC , SOX2 , and NANOG . n = 3; *, p < 0.05. H–J) Sorted DPP4 +/− fibroblasts underwent adipogenic induction, followed by Oil Red O staining and quantification analysis (H–I). Ten random fields per sample were analyzed. The mRNA levels of adipogenesis‐related genes were detected using RT‐qPCR (J); n = 3. Scale bars, 100 μm in (A, B, C, D, and H). Data are presented as mean ± SEM; statistical significance was determined by Student's t ‐test.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: In Vitro, Derivative Assay, Isolation, Marker, Flow Cytometry, Fluorescence, FACS, Quantitative RT-PCR, Staining

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: DPP4 − KMSCs demonstrate enhanced adipogenic capacity, whereas DPP4 + KMSCs demonstrate increased fibrotic capacity in vivo. FACS‐sorted DPP4 + and DPP4 − cells were subcutaneously transplanted into Balb/c nude mice. A) The volume of subcutaneously transplanted KMSCs in mice was measured, n = 9. B–D) Adipocyte formation was evaluated by (B) H&E staining (black arrow) and (C) immunofluorescence staining of Perilipin and HLA‐ABC. The black arrow indicates the newly formed adipocytes. (D) The numbers of adipocytes and immature adipocytes were analyzed; n = 6. E,F) Masson's trichrome staining and G,H) immunofluorescence staining of COL1A1 were performed to evaluate collagen deposition. The expression of I,J) PPARγ and K,L) CEBPα was examined by immunofluorescence staining. n = 6. **, p < 0.01. Scale bars, 200 μm in (B), 100 μm in (C), 20 μm in (E, G, I, and K). Data were presented as mean ± SEM. Statistical significance was determined by Student's t ‐test.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: In Vivo, Staining, Immunofluorescence, Expressing

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: Sitagliptin‐mediated adipogenic promotion is dependent on protection of IGF1 from DPP4 cleavage. A) Schematic of DPP4‐driven peptide/protein truncation. B–D) DPP4 directly truncates IGF1 but not BMP4. Recombinant human IGF‐I or BMP4 was incubated with recombinant human DPP4 Fc chimera for the cleaving assay, and the product was analyzed using HPLC‐MS/MS. (B) The peptide starting with “ETLC” (red arrow) represented the truncated product of IGF1 by DPP4 and (C) peptide starting with “KHHS” represented the truncated product of BMP4 by DPP4. (D) Percentages of truncated product from the cleaving assay were calculated. E–I) KMSCs underwent adipogenic induction and treated with sitagliptin (20 μM) or combined with the IGF‐1 signaling pathway inhibitor picropodophyllin (PPP, 50 nM), the mRNA and protein levels of adipogenesis‐related molecules were detected by RT‐qPCR E) and F–I) western blotting and quantification analysis. n = 3; *, p < 0.05, **, p < 0.01. Cont. medium, control medium, diff. medium, differentiation medium. Sitag, sitagliptin. M, marker. Data was presented as mean ± SEM. Statistical significance was determined by one‐way analysis of variance (ANOVA) followed by Tukey's HSD post hoc test.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques: Recombinant, Incubation, Tandem Mass Spectroscopy, Quantitative RT-PCR, Western Blot, Control, Marker

Journal: Small Science

Article Title: Sustained‐Release Sitagliptin Microneedles for Scar Prevention via Fibroblast‐to‐Adipocyte Conversion

doi: 10.1002/smsc.202500140

Figure Lengend Snippet: Illustration of our work. In scar tissues, IGF1 is cleaved by DPP4 enzyme in DPP4 + KMSC. Cleaved IGF1 may induce KMSC differentiation toward myofibroblasts, whereas IGF1 protected by sitagliptin acts as an adipogenic agent.

Article Snippet: To identify the direct truncation of IGF1 by DPP4, recombinant human IGF1 (rhIGF1, 291‐G1, R&D Systems, Minneapolis, MN) was incubated with a recombinant human DPP4 Fc chimera (11141‐SE, R&D Systems). rhDPP4/Fc was diluted to a concentration of 0.2 ng μL −1 in the assay buffer, and 1 μL of the diluted rhDPP4/Fc was added to 15 μL of diluted rhIGF1 (1 μg μL −1 ).

Techniques:

Journal: Heliyon

Article Title: Exploring recent progress of molecular farming for therapeutic and recombinant molecules in plant systems

doi: 10.1016/j.heliyon.2024.e37634

Figure Lengend Snippet: Commercial land scape of PMF products.

Article Snippet: Planet Biotechnology , USA , Plantibodies (CMG2-Fc, DPP4-Fc) , https://www.planetbiotechnology.com/.

Techniques: Vaccines, Expressing, Diagnostic Assay