Cell Cycle Analysis of the Postnatal Mouse Pancreas

Webb, Stanley; Dore, Bruce A.; Grogan, McLean

doi:10.1159/000241578

Cited by 9 publications

(11 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results for the control tissues agree with previous findings obtained by other methods in showing a higher frequency of polyploid nuclei in the liver (Epstein, 1967; Brodsky & Uryvaeva, 1977, 1985) than in the pancreas (Larsen & Nielsen, 1978; Webb et al. 1982; Ornitz et al.…”

Section: Discussionsupporting

confidence: 91%

“…Possible beneficial properties of polyploidy include protection against accumulation of recessive mutations or enhanced biosynthetic capability. Polyploid cells often occur in tissues with specialized biosynthetic secretary or storage functions (Brodsky & Uryvaeva, 1977, 1985; Webb et al. 1982), as is the case with the liver, pancreas and corpus luteum.…”

Section: Discussionmentioning

confidence: 99%

“…1999). There is also an age‐related increase in the frequency of polyploid nuclei in the mouse pancreas (Webb et al. 1982) and liver (Alfert & Geschwind, 1958; Inamdar, 1958; Epstein, 1967; Evans, 1976; Brodsky & Uryvaeva, 1977).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Polyploid cells in the mouse ovary

et al. 2003

View full text Add to dashboard Cite

Cell ploidy in the ovarian follicle and corpus luteum was investigated by DNA in situ hybridization to a reiterated, chromosome 3 transgene in mice that were hemizygous for the transgene. This approach was first validated by analysis of mouse kidney, pancreas and liver control tissues, which contain different frequencies of polyploid nuclei. Polyploid nuclei (with multiple hybridization signals) were seen in histological sections of both ovarian follicles and corpora lutea. The frequency of polyploid nuclei in follicles showed no consistent relationship with age (between 6 weeks and 10 months) but polyploid nuclei were significantly more abundant in corpora lutea than follicles (6.3% vs. 2.5%). This implies that production of polyploid cells is more closely associated with differentiation of ovarian follicles into corpora lutea than with the age of the female. Polyploidy tended to be more frequent in corpora lutea of mice that had mated even if they did not become pregnant. This study has highlighted the presence of polyploid cells in the mouse ovarian follicle and corpus luteum and has identified mating as a possible trigger for polyploidy in the corpus luteum. Further work is required to determine the physiological role of polyploid ovarian cells in reproduction.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Polyploid cells in the mouse ovary

et al. 2003

View full text Add to dashboard Cite

show abstract

“…There was a high incidence of tetraploid cells in the pancreas of the mouse compared with that of the rat. Webb et al (1982) reported a n incidence of diploid nuclei in the adult mouse pancreas similar to that found in the present study, although those workers considered that most of the remaining nuclei were in S, G2, or M phase. In the present study, the remaining nuclei made up a single symmetrical peak with tetraploid DNA content.…”

Section: Ratsupporting

confidence: 85%

Changes in numbers of pancreatic acinar cell nuclei and in DNA content during raw soya flour feeding in mice

Morgan

1990

Am. J. Anat.

View full text Add to dashboard Cite

Nuclei of pancreatic cells were isolated by trypsin-detergent digestion of fresh tissue and stained with propidium iodide, and nuclear DNA was measured by flow cytometry. Samples were isolated from mice fed either chow or raw soya flour (RSF) for periods ranging from 1 day to 48 weeks, beginning at 4 weeks of age. In chow-fed mice, the pancreas contained about 80% diploid (2N) and 20% tetraploid (4N) cells at the start of the study, but tetraploidy gradually increased to about 40% 2 weeks later (6 weeks of age) and remained at this level from that time onwards. Low levels of octaploid nuclei (8N) were also present in some animals after 2 weeks. In RSF-fed mice, about 20% tetraploid nuclei were also present for 1 and 2 days after starting RSF, but by 4 days tetraploidy had increased significantly to 40% and by 14 days had further increased to 50%. This level was significantly higher than that seen in chow-fed animals and was maintained for up to 48 weeks. Significantly higher numbers of octaploid nuclei were also present in the RSF-fed animals. In both chow- and RSF-fed mice, most cells were mononuclear, averaging 70% in chow-fed and 64% in RSF-fed animals. This difference was significant. This study shows that the mouse pancreas differs from the rat pancreas in the absence of a large population of binucleate acinar cells and the presence of considerable nuclear tetraploidy. Raw soya flour feeding leads to significant changes in these features, but in this species these changes do not appear to predispose to neoplasia.

show abstract

“…In mammals, polyploid cells have been observed in different tissues including the placenta, bone marrow, heart, liver, and pancreas [ 2 , 4 ]. Interestingly, in the pancreas both the endocrine and exocrine cells undergo programmed polyploidization when mice are weaned resulting in a heterogeneous population of cells with different ploidy status [ 4 , 5 ]. The biological significance of polyploid cells in the pancreas is not known.…”

Section: Introductionmentioning

confidence: 99%

Atypical E2f functions are critical for pancreas polyploidization

et al. 2018

View full text Add to dashboard Cite

The presence of polyploid cells in the endocrine and exocrine pancreas has been reported for four decades. In rodents, pancreatic polyploidization is initiated after weaning and the number of polyploid cells increases with age. Surprisingly the molecular regulators and biological functions of polyploidization in the pancreas are still unknown. We discovered that atypical E2f activity is essential for polyploidization in the pancreas, using an inducible Cre/LoxP approach in new-born mice to delete ubiquitously the atypical E2f transcription factors, E2f7 and E2f8. In contrast to its critical role in embryonic survival, conditional deletion of both of both atypical E2fs in newborn mice had no impact on postnatal survival and mice lived until old age. However, deficiency of E2f7 or E2f8 alone was sufficient to suppress polyploidization in the pancreas and associated with only a minor decrease in blood serum levels of glucose, insulin, amylase and lipase under 4 hours starvation condition compared to wildtype littermates. In mice with fewer pancreatic polyploid cells that were fed ad libitum, no major impact on hormones or enzymes levels was observed. In summary, we identified atypical E2fs to be essential for polyploidization in the pancreas and discovered that postnatal induced loss of both atypical E2fs in many organs is compatible with life until old age.

show abstract

Cell Cycle Analysis of the Postnatal Mouse Pancreas

Cited by 9 publications

References 9 publications

Polyploid cells in the mouse ovary

Polyploid cells in the mouse ovary

Changes in numbers of pancreatic acinar cell nuclei and in DNA content during raw soya flour feeding in mice

Atypical E2f functions are critical for pancreas polyploidization

Contact Info

Product

Resources

About