In vitro and in vivo expression of Galalpha-(1,3)Gal on porcine islet cells is age dependent

The expression of Galalpha-(1,3)Gal (alphaGal) on porcine islet cells remains controversial. Several groups have reported that porcine islet endocrine cells do not express alphaGal while we have shown in neonatal porcine islets (NPI) that beta cells do express this antigen. We hypothesize that endocrine cells expressing alphaGal on NPI are less mature cells that may have originated from ductal cells and that expression of this antigen disappears as they develop into fully mature beta cells. Thus, we further examined alphaGal expression on various porcine islet cell preparations and correlated this with the proportion of cytokeratin 7 (CK7)-positive ductal cells. In vitro and in vivo expression of alphaGal and CK7 was significantly (P<0.05) higher in less mature NPI cells compared with matured NPI and adult porcine islet cells while the reverse was observed in the proportion of beta cells. Moreover, a significantly higher proportion of CK7-positive cells was detected in the Gal-expressing population compared with non-expressing cells. In contrast, a higher proportion of beta cells was observed in the Gal-negative population compared with the Gal-positive population. These data showed a reduced expression of alphaGal and CK7 as porcine islet cells mature into beta cells suggesting a possible role for alphaGal in the maturation of pancreatic endocrine beta cells.

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Nicorandil improves diabetes and rat islet beta-cell damage induced by streptozotocin in vivo and in vitro

Acta Endocrinologica ◽

10.1530/eje.0.1510277 ◽

2004 ◽

pp. 277-285 ◽

Cited By ~ 13

Author(s):

K Kasono ◽

T Yasu ◽

A Kakehashi ◽

N Kinoshita ◽

H Tamemoto ◽

...

Keyword(s):

Beta Cell ◽

Beta Cells ◽

Islet Cells ◽

Cell Damage ◽

Neonatal Rat ◽

Islet Beta Cells ◽

Islet Beta Cell ◽

Beta Cell Damage

OBJECTIVE: N-(2-hydroxyethyl)-nicotinamide nitrate (nicorandil) is a unique anti-anginal agent, reported to act as both an ATP-sensitive K(+) channel opener (PCO) and a nitric oxide donor. It also has an anti-oxidant action. We examined the effects of nicorandil on streptozotocin (STZ)-induced islet beta-cell damage both in vivo and in vitro. DESIGN AND METHODS: STZ-induced diabetic Brown Norway rats (STZ-DM) were fed with nicorandil-containing chow from day 2 (STZ-DM-N48), 3 (STZ-DM-N72), and 4 (STZ-DM-N96) to day 30. Body weight, blood glucose, and plasma insulin were measured every week. For the in vitro assay, neonatal rat islet-rich cultures were performed and cells were treated with nicorandil from 1 h before to 2 h after exposure to STZ for 30 min. Insulin secretion from islet cells was assayed after an additional 24 h of culture. We also observed the effect of nicorandil on the generation of reactive oxygen species (ROS) from rat inslinoma cells (RINm5F). RESULTS: Body weight loss and blood glucose levels of STZ-DM-N48 rats were significantly lower than those of STZ-DM rats. Immunohistochemical staining of insulin showed preservation of insulin-secreting islet beta-cells in STZ-DM-N48 rats. Nicorandil also dose-dependently recovered the insulin release from neonatal rat islet cells treated with STZ in in vitro experiments. Nicorandil did not act as a PCO on neonatal rat islet beta-cells or RINm5F cells, and did not show an inhibitory effect on poly(ADP-ribose) polymerase-1. However, the drug inhibited the production of ROS stimulated by high glucose (22.0 mmol/l) in RINm5F cells. CONCLUSIONS: These results suggested that nicorandil improves diabetes and rat islet beta-cell damage induced by STZ in vivo and in vitro. It protects islet beta-cells, at least partly, via a radical scavenging effect.

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Prolonged Survival of Microencapsulated Neonatal Porcine Islet Xenografts in Immune-Competent Mice without Antirejection Therapy

Cell Transplantation ◽

10.3727/096368908787236602 ◽

2008 ◽

Vol 17 (10-11) ◽

pp. 1243-1256 ◽

Cited By ~ 14

Author(s):

Tsunehiro Kobayashi ◽

Hossein Arefanian ◽

George Harb ◽

Eric B. Tredget ◽

Ray V. Rajotte ◽

...

Keyword(s):

Islet Graft ◽

Term Survival ◽

Long Term Survival ◽

Porcine Islet ◽

In Vivo Culture ◽

Neonatal Porcine Islets ◽

Deficient Mice

Several studies have demonstrated that in vitro culture of islets prolonged islet graft survival in immune-competent mice without administration of antirejection drugs. However, we recently showed that in vitro cultured microencapsulated neonatal porcine islets (NPI) were rejected in immune-competent mice not receiving antirejection therapy. The aim of this study was to determine whether culture of microencapsulated NPI in vivo could promote long-term survival of microencapsulated NPI in immune-competent mice without administration of antirejection drugs. Microencapsulated NPI that were cultured in vitro for 7 and 50 days or transplanted initially in immune-deficient C.B.-17 SCID-BEIGE mice for 100 days (in vivo cultured) were characterized and transplanted into streptozotocin-induced diabetic immune-competent BALB/c mice. Day 50 in vitro cultured and day 100 in vivo cultured microencapsulated NPI showed significantly higher insulin and DNA content, indicating maturation of NPI compared to day 7 in vitro cultured microencapsulated NPI. Interestingly, in vivo cultured microencapsulated NPI expressed lower levels of porcine antigens compared to day 7 and day 50 in vitro cultured microencapsulated NPI. Transplantation of day 7 in vitro cultured microencapsulated NPI did not reverse diabetes in immune-competent BALB/c mouse recipients. In contrast, transplantation of day 50 in vitro cultured and in vivo cultured microencapsulated NPI into diabetic immune-competent BALB/c mice resulted in the immediate reversal of hyperglycemia within 2 days posttransplantation. However, all recipients of day 50 in vitro cultured microencapsulated NPI eventually rejected their grafts by day 15 posttransplantation, while 6 of 10 BALB/c mouse recipients of in vivo cultured microencapsulated NPI maintained normoglycemia for 100 days posttransplantation. These results show that in vivo culture of NPI in immune-deficient mice results in the modulation of NPI, which allows for their long-term survival in immune-competent mice without antirejection therapy.

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Single-cell transcriptome lineage tracing of human pancreatic development identifies distinct developmental trajectories of alpha and beta cells

10.1101/2021.01.14.426320 ◽

2021 ◽

Author(s):

Li Lin ◽

Yufeng Zhang ◽

Weizhou Qian ◽

Yao Liu ◽

Yingkun Zhang ◽

...

Keyword(s):

Single Cell ◽

Beta Cells ◽

Developmental Process ◽

Islet Cells ◽

Developmental Trajectories ◽

Human Islets ◽

Lineage Tracing ◽

Cell Transcriptome

ABSTRACTIn comparison to mouse, the developmental process of human islets has not been properly elucidated. The advancement of single cell RNA-seq technology enables us to study the properties of alpha and beta cells at single cell resolution. By using mitochondrial genome variants as endogenous lineage-tracing markers, we found that human alpha and beta cells have different lineage features. This finding suggests specific endocrine progenitors for alpha and beta cells, which is different from mouse islet cells. This strategy was also applied to a study of chemically-induced islet cell reprogramming and was used to help identify artemether-induced alpha-to-beta trans-differentiation in human islets. The computational results of this study will inspire future studies to establish, maintain, and expand beta cell-specific progenitors in vitro and in vivo.

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