Reduced Expression of the Co-regulator TLE1 in Type 2 Diabetes Is Associated with Increased Islet α-Cell Number.

ß-Cell dysfunction in type 2 diabetes (T2D) is associated with loss of cellular identity and mis-expression of alternative islet hormones, including glucagon. The molecular basis for these cellular changes has been attributed to dysregulation of core ß-cell transcription factors, which regulate ß-cell identity through activating and repressive mechanisms. The TLE1 gene lies near a T2D susceptibility locus and, recently, the glucagon repressive actions of this transcriptional coregulator have been demonstrated in vitro. We investigated whether TLE1 expression is disrupted in human T2D, and whether this is associated with increased islet glucagon-expressing cells. Automated image analysis following immunofluorescence in donors with (n = 7) and without (n = 7) T2D revealed that T2D was associated with higher islet α/ß cell ratio (Control: 0.7 ± 0.1 vs T2D: 1.6 ± 0.4; P < .05) and an increased frequency of bihormonal (insulin+/glucagon+) cells (Control: 0.8 ± 0.2% vs T2D: 2.0 ± 0.4%, P < .05). In nondiabetic donors, the majority of TLE1-positive cells were mono-hormonal ß-cells (insulin+/glucagon-: 98.2 ± 0.5%; insulin+/glucagon+: 0.7 ± 0.2%; insulin-/glucagon+: 1.1 ± 0.4%; P < .001). TLE1 expression was reduced in T2D (Control: 36 ± 2.9% vs T2D: 24 ± 2.6%; P < .05). Reduced islet TLE1 expression was inversely correlated with α/ß cell ratio (r = -0.55; P < .05). TLE1 knockdown in EndoC-ßH1 cells was associated with a 2.5-fold increase in glucagon gene mRNA and mis-expression of glucagon in insulin-positive cells. These data support TLE1 as a putative regulator of human ß-cell identity, with dysregulated expression in T2D associated with increased glucagon expression potentially reflecting ß- to α-cell conversion.

In Situ Analysis Reveals That CFTR Is Expressed in Only a Small Minority of ß-Cells in Normal Adult Human Pancreas.

CONTEXT: Although diabetes affects 40% to 50% of adults with cystic fibrosis, remarkably little is known regarding the underlying mechanisms leading to impaired pancreatic ß-cell insulin secretion. Efforts toward improving the functional ß-cell deficit in cystic fibrosis-related diabetes (CFRD) have been hampered by an incomplete understanding of whether ß-cell function is intrinsically regulated by cystic fibrosis transmembrane conductance regulator (CFTR). Definitively excluding meaningful CFTR expression in human ß-cells in situ would contribute significantly to the understanding of CFRD pathogenesis. OBJECTIVE: To determine CFTR messenger ribonucleic acid (mRNA) and protein expression within ß-cells in situ in the unmanipulated human pancreas of donors without any known pancreatic pathology. DESIGN: In situ hybridization for CFTR mRNA expression in parallel with insulin immunohistochemical staining and immunofluorescence co-localization of CFTR with insulin and the ductal marker, Keratin-7 (KRT7), were undertaken in pancreatic tissue blocks from 10 normal adult, nonobese deceased organ donors over a wide age range (23-71 years) with quantitative image analysis. RESULTS: CFTR mRNA was detectable in a mean 0.45% (range 0.17%-0.83%) of insulin-positive cells. CFTR protein expression was co-localized with KRT7. One hundred percent of insulin-positive cells were immunonegative for CFTR. CONCLUSIONS: For the first time, in situ CFTR mRNA expression in the unmanipulated pancreas has been shown to be present in only a very small minority (<1%) of normal adult ß-cells. These data signal a need to move away from studying endocrine-intrinsic mechanisms and focus on elucidation of exocrine-endocrine interactions in human cystic fibrosis.

Complications related to entry techniques for laparoscopy in 159 dogs and cats.

OBJECTIVE: To report the frequency and risk factors of complications related to 3 entry techniques for laparoscopy in small animals. STUDY DESIGN: Single-institution retrospective case series. ANIMALS: 159 client-owned dogs and cats. METHODS: Medical records were reviewed for dogs and cats undergoing laparoscopic surgery with carbon dioxide (CO2 ) insufflation between 2006 and 2018. Data including entry site, entry technique, signalment, body conformation, complications, and operating surgeon/resident were analyzed by univariate regression analysis. Factors with P < .25 were included in multivariate regression analysis. RESULTS: Complications occurred in 33 of 159 (21%) surgeries and were considered minor (CO2 leaks, omental insufflation, repeated entry) in 30 of 33 (91%) cases. The Ternamian visual entry, modified Hasson, and Veress needle entry techniques were associated with complications in 7 (9%), 17 (26%), and 9 (60%) surgeries, respectively. Major complications occurred in 3 of 159 (2%) surgeries, in which entry-related hemorrhage prompted conversion to an open technique (2 [13%] entries with Veress needle) and 1 [1%] with the Ternamian visual). Entry location and entry technique remained significant in the final multivariate model. Complications were 11.7 times more likely after a paramedian entry than after a midline entry; the odds ratio of complications were 5 and 28 times higher after modified Hasson and Veress needle entries, respectively, than after Ternamian visual entry. CONCLUSION: In this study, a Ternamian visual entry technique and midline entry site appeared associated with fewer complications than 2 other techniques. CLINICAL SIGNIFICANCE: The findings in this study are preliminary, and superiority of any entry technique must be reevaluated in a prospective randomized controlled study.