Quantitative 3D OPT and LSFM datasets of pancreata from mice with streptozotocin-induced diabetes

Mouse models for streptozotocin (STZ) induced diabetes probably represent the most widely used systems for preclinical diabetes research, owing to the compound’s toxic effect on pancreatic β-cells. However, a comprehensive view of pancreatic β-cell mass distribution subject to STZ administration is lacking. Previous assessments have largely relied on the extrapolation of stereological sections, which provide limited 3D-spatial and quantitative information. This data descriptor presents multiple ex vivo tomographic optical image datasets of the full β-cell mass distribution in mice subject to single high and multiple low doses of STZ administration, and in glycaemia recovered mice. The data further include information about structural features, such as individual islet β-cell volumes, spatial coordinates, and shape as well as signal intensities for both insulin and GLUT2. Together, they provide the most comprehensive anatomical record of the effects of STZ administration on the islet of Langerhans in mice. As such, this data descriptor may serve as reference material to facilitate the planning, use and (re)interpretation of this widely used disease model.

Measurement(s)	Fluorescent antibody staining of Insulin and GLUT2 in whole mouse pancreata
Technology Type(s)	Optical Projection Tomography • Light Sheet Fluorescence Microscopy (Ultramicroscope)
Factor Type(s)	mouse genotype • Streptozotocin dosage
Sample Characteristic - Organism	Mus musculus

Insights into the etiology and physiopathology of MODY5/HNF1B pancreatic phenotype with a mouse model of the human disease

Maturity-onset diabetes of the young type 5 (MODY5) is due to heterozygous mutations or deletion of HNF1B. No mouse models are currently available to recapitulate the human MODY5 disease. Here, we investigate the pancreatic phenotype of a unique MODY5 mouse model generated by heterozygous insertion of a human HNF1B splicing mutation at the intron-2 splice donor site in the mouse genome. This Hnf1bsp2/+ model generated with targeted mutation of Hnf1b mimicking the c.544+1G>T (T) mutation identified in humans, results in alternative transcripts and a 38% decrease of native Hnf1b transcript levels. As a clinical feature of MODY5 patients, the hypomorphic mouse model Hnf1bsp2/+ displays glucose intolerance. Whereas Hnf1bsp2/+ isolated islets showed no altered insulin secretion, we found a 65% decrease in pancreatic insulin content associated with a 30% decrease in total large islet volume and a 20% decrease in total β-cell volume. These defects were associated with a 30% decrease in expression of the pro-endocrine gene Neurog3 that we previously identified as a direct target of Hnf1b, showing a developmental etiology. As another clinical feature of MODY5 patients, the Hnf1bsp2/+ pancreases display exocrine dysfunction with hypoplasia. We observed chronic pancreatitis with loss of acinar cells, acinar-to-ductal metaplasia, and lipomatosis, with upregulation of signaling pathways and impaired acinar cell regeneration. This was associated with ductal cell deficiency characterized by shortened primary cilia. Importantly, the Hnf1bsp2/+ mouse model reproduces the pancreatic features of the human MODY5/HNF1B disease, providing a unique in vivo tool for molecular studies of the endocrine and exocrine defects and to advance basic and translational research. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Retraction Note: Transient cytokine treatment induces acinar cell reprogramming and regenerates functional beta cell mass in diabetic mice

This article has been retracted; see accompanying Retraction Note, which can be accessed via a link at the top of the paper.

Sperm count in Swedish clinical stage I testicular cancer patients following adjuvant treatment

BACKGROUND

Little is known regarding sperm production following adjuvant treatment in testicular cancer (TC) clinical stage I (CS I) patients.

PATIENTS AND METHODS

A total of 182 TC patients aged 18-50 years were prospectively included during 2001-2006 at any given time within 5 years of orchiectomy. Semen samples were delivered postorchiectomy but before further treatment, 6, 12, 24, 36 and 60 months (T0-T60) after completed therapy. Total sperm number (TSN) and sperm concentration (SC) were used as measurements of testicular function. Four groups according to treatment modality were identified; Radiotherapy; To a total dose of 25.2 Gy to the infradiaphragmal paraaortic and ipsilateral iliac lymph nodes (RT, N = 70), one cycle of adjuvant BEP (bleomycin, etoposide, cisplatin, 5 day regimen) (BEP, N = 62), one cycle of adjuvant carboplatin AUC 7 (Carbo, N = 22), and patients managed by surveillance (SURV, N = 28).

RESULTS

In the cross-sectional analysis, a significant but transient drop in mean TSN and mean SC (T0-T60) was seen at T6 after radiotherapy. Apart from a significant increase in mean SC at T12 compared with baseline, no significant differences were observed in the other treatment groups. In 119 patients delivering 3 or more samples, values in TSN and SC were rather stable over time. Azoospermic patients (N = 11) were observed in most treatment groups except for in the BEP group. During follow-up, one azoospermic patient belonging to the Carbo group became normospermic.

CONCLUSIONS

No clinically significant long-term effect on TSN or SC associated with adjuvant treatment in TC CSI patients was found. However, as patients may have low sperm counts before orchiectomy as well as after adjuvant treatment, we offer sperm banking before orchiectomy as assisted reproductive measures may be necessary regardless of treatment given.

The effect of hypergastrinemia following sleeve gastrectomy and pantoprazole on type 2 diabetes mellitus and beta-cell mass in Goto-Kakizaki rats

PURPOSE

Metabolic surgery alters the secretion of gastrointestinal hormones that influence glycemic control. Elevated gastrin has been suggested to benefit patients with type 2 diabetes and has been reported following sleeve gastrectomy in rats. The present study compares the effect of hypergastrinemia following sleeve gastrectomy with proton-pump inhibitor therapy on glycemic control and beta-cell mass in lean, diabetic animals.

METHODS

Thirty-three diabetic Goto-Kakizaki rats were randomized into pantoprazole + sham operation (GK-PPI), sleeve gastrectomy (GK-SG) and vehicle + sham operation (GK-V). Body weight, glucose parameters, HbA1c, glucagon-like peptide 1, gastrin, insulin and lipids were evaluated for eighteen postoperative weeks. Total beta-cell mass was quantified by optical projection tomography.

RESULTS

After surgery, body weight development was equal among groups (P _g = 0.75). Fasting and stimulated gastrin increased for GK-PPI and GK-SG vs. GK-V (p < 0.05 for all). Fasting blood glucose was decreased for GK-PPI and GK-SG vs. GK-V (p < 0.05 and p = 0.052). HbA1c was lower for GK-SG vs. GK-V at 6 weeks and for GK-PPI vs. GK-V at twelve- and eighteen weeks postoperative (p < 0.05 for all); a borderline difference was observed for GK-SG vs. GK-V at 18 weeks (p = 0.054). Total- and LDL cholesterol was elevated for GK-PPI compared to the other two groups (p < 0.05 for all). Beta-cell mass did not differ among groups (p = 0.35).

CONCLUSIONS

Hypergastrinemia following sleeve gastrectomy and pantoprazole has a similar, modest effect on glycemic control in Goto-Kakizaki rats but does not enhance beta-cell mass after 18 weeks. Hypergastrinemia in the setting of T2DM might be of clinical relevance.

Biochemical profiling of diabetes disease progression by multivariate vibrational microspectroscopy of the pancreas

Despite the dramatic increase in the prevalence of diabetes, techniques for in situ studies of the underlying pancreatic biochemistry are lacking. Such methods would facilitate obtaining mechanistic understanding of diabetes pathophysiology and aid in prognostic and/or diagnostic assessments. In this report we demonstrate how a multivariate imaging approach (orthogonal projections to latent structures - discriminant analysis) can be applied to generate full vibrational microspectroscopic profiles of pancreatic tissues. These profiles enable extraction of known and previously unrecorded biochemical alterations in models of diabetes, and allow for classification of the investigated tissue with regards to tissue type, strain and stage of disease progression. Most significantly, the approach provided evidence for dramatic alterations of the pancreatic biochemistry at the initial onset of immune-infiltration in the Non Obese Diabetic model for type 1 diabetes. Further, it enabled detection of a previously undocumented accumulation of collagen fibrils in the leptin deficient ob/ob mouse islets. By generating high quality spectral profiles through the tissue capsule of hydrated human pancreata and by in vivo Raman imaging of pancreatic islets transplanted to the anterior chamber of the eye, we provide critical feasibility studies for the translation of this technique to diagnostic assessments of pancreatic biochemistry in vivo.

Spatial and quantitative datasets of the pancreatic β-cell mass distribution in lean and obese mice

A detailed understanding of pancreatic β-cell mass distribution is a key element to fully appreciate the pathophysiology of models of diabetes and metabolic stress. Commonly, such assessments have been performed by stereological approaches that rely on the extrapolation of two-dimensional data and provide very limited topological information. We present ex vivo optical tomographic data sets of the full β-cell mass distribution in cohorts of obese ob/ob mice and their lean controls, together with information about individual islet β-cell volumes, their three-dimensional coordinates and shape throughout the volume of the pancreas between 4 and 52 weeks of age. These data sets offer the currently most comprehensive public record of the β-cell mass distribution in the mouse. As such, they may serve as a quantitative and topological reference for the planning of a variety of in vivo or ex vivo experiments including computational modelling and statistical analyses. By shedding light on intra- and inter-lobular variations in β-cell mass distribution, they further provide a powerful tool for the planning of stereological sampling assessments.

Intra-islet lesions and lobular variations in β-cell mass expansion in ob/ob mice revealed by 3D imaging of intact pancreas

The leptin deficient ob/ob mouse is a widely used model for studies on initial aspects of metabolic disturbances leading to type 2 diabetes, including insulin resistance and obesity. Although it is generally accepted that ob/ob mice display a dramatic increase in β-cell mass to compensate for increased insulin demand, the spatial and quantitative dynamics of β-cell mass distribution in this model has not been assessed by modern optical 3D imaging techniques. We applied optical projection tomography and ultramicroscopy imaging to extract information about individual islet β-cell volumes throughout the volume of ob/ob pancreas between 4 and 52 weeks of age. Our data show that cystic lesions constitute a significant volume of the hyperplastic ob/ob islets. We propose that these lesions are formed by a mechanism involving extravasation of red blood cells/plasma due to increased islet vessel blood flow and vessel instability. Further, our data indicate that the primary lobular compartments of the ob/ob pancreas have different potentials for expanding their β-cell population. Unawareness of the characteristics of β-cell expansion in ob/ob mice presented in this report may significantly influence ex vivo and in vivo assessments of this model in studies of β-cell adaptation and function.

A novel mouse model of tuberous sclerosis complex (TSC): eye-specific Tsc1-ablation disrupts visual-pathway development

Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome that is best characterised by neurodevelopmental deficits and the presence of benign tumours (called hamartomas) in affected organs. This multi-organ disorder results from inactivating point mutations in either the TSC1 or the TSC2 genes and consequent activation of the canonical mammalian target of rapamycin complex 1 signalling (mTORC1) pathway. Because lesions to the eye are central to TSC diagnosis, we report here the generation and characterisation of the first eye-specific TSC mouse model. We demonstrate that conditional ablation of Tsc1 in eye-committed progenitor cells leads to the accelerated differentiation and subsequent ectopic radial migration of retinal ganglion cells. This results in an increase in retinal ganglion cell apoptosis and consequent regionalised axonal loss within the optic nerve and topographical changes to the contra- and ipsilateral input within the dorsal lateral geniculate nucleus. Eyes from adult mice exhibit aberrant retinal architecture and display all the classic neuropathological hallmarks of TSC, including an increase in organ and cell size, ring heterotopias, hamartomas with retinal detachment, and lamination defects. Our results provide the first major insight into the molecular etiology of TSC within the developing eye and demonstrate a pivotal role for Tsc1 in regulating various aspects of visual-pathway development. Our novel mouse model therefore provides a valuable resource for future studies concerning the molecular mechanisms underlying TSC and also as a platform to evaluate new therapeutic approaches for the treatment of this multi-organ disorder.

Editors' choice: Conditional deletion of Tsc1 in the eye results in hamartoma formation and defects in retinal ganglion cell development – a novel mouse model providing insights into visual pathway involvement in TSC.

Targeted Disruption of ALK Reveals a Potential Role in Hypogonadotropic Hypogonadism

Mice lacking ALK activity have previously been reported to exhibit subtle behavioral phenotypes. In this study of ALK of loss of function mice we present data supporting a role for ALK in hypogonadotropic hypogonadism in male mice. We observed lower level of serum testosterone at P40 in ALK knock-out males, accompanied by mild disorganization of seminiferous tubules exhibiting decreased numbers of GATA4 expressing cells. These observations highlight a role for ALK in testis function and are further supported by experiments in which chemical inhibition of ALK activity with the ALK TKI crizotinib was employed. Oral administration of crizotinib resulted in a decrease of serum testosterone levels in adult wild type male mice, which reverted to normal levels after cessation of treatment. Analysis of GnRH expression in neurons of the hypothalamus revealed a significant decrease in the number of GnRH positive neurons in ALK knock-out mice at P40 when compared with control littermates. Thus, ALK appears to be involved in hypogonadotropic hypogonadism by regulating the timing of pubertal onset and testis function at the upper levels of the hypothalamic-pituitary gonadal axis.

Differential regulation of myosin heavy chains defines new muscle domains in zebrafish

Numerous muscle lineages are formed during myogenesis within both slow- and fast-specific cell groups. New muscle domains are identified along the anteroposterior axis in zebrafish and are defined by individual nonoverlapping expression of myosin heavy chain isoforms differentially regulated by retinoic acid and wnt.

Numerous muscle lineages are formed during myogenesis within both slow- and fast-specific cell groups. In this study, we show that six fast muscle–specific myosin heavy chain genes have unique expression patterns in the zebrafish embryo. The expression of tail-specific myosin heavy chain (fmyhc2.1) requires wnt signaling and is essential for fast muscle organization within the tail. Retinoic acid treatment results in reduced wnt signaling, which leads to loss of the fmyhc2.1 domain. Retinoic acid treatment also results in a shift of muscle identity within two trunk domains defined by expression of fmyhc1.2 and fmyhc1.3 in favor of the anteriormost myosin isoform, fmyhc1.2. In summary, we identify new muscle domains along the anteroposterior axis in the zebrafish that are defined by individual nonoverlapping, differentially regulated expression of myosin heavy chain isoforms.

Transient cytokine treatment induces acinar cell reprogramming and regenerates functional beta cell mass in diabetic mice

Reprogramming of pancreatic exocrine cells into cells resembling beta cells may provide a strategy for treating diabetes. Here we show that transient administration of epidermal growth factor and ciliary neurotrophic factor to adult mice with chronic hyperglycemia efficiently stimulates the conversion of terminally differentiated acinar cells to beta-like cells. Newly generated beta-like cells are epigenetically reprogrammed, functional and glucose responsive, and they reinstate normal glycemic control for up to 248 d. The regenerative process depends on Stat3 signaling and requires a threshold number of Neurogenin 3 (Ngn3)-expressing acinar cells. In contrast to previous work demonstrating in vivo conversion of acinar cells to beta-like cells by viral delivery of exogenous transcription factors, our approach achieves acinar-to-beta-cell reprogramming through transient cytokine exposure rather than genetic modification.

Improving signal detection in emission optical projection tomography via single source multi-exposure image fusion

We demonstrate a technique to improve structural data obtained from Optical Projection Tomography (OPT) using Image Fusion (IF) and contrast normalization. This enables the visualization of molecular expression patterns in biological specimens with highly variable contrast values. In the approach, termed IF-OPT, different exposures are fused by assigning weighted contrasts to each. When applied to projection images from mouse organs and digital phantoms our results demonstrate the capability of IF-OPT to reveal high and low signal intensity details in challenging specimens. We further provide measurements to highlight the benefits of the new algorithm in comparison to other similar methods.

Cancer patients' awareness about their diagnosis: a population-based study

BACKGROUND

The aim of the study was to evaluate Norwegian cancer patients' awareness of their prior cancer diagnosis in a general population-based study.

METHODS

A cross-sectional population-based study of cancer patients' responses to the index question: 'Do you have or have you had cancer?' was carried out. We assessed correctness of the response in relation to cancer site, date of diagnosis, marital status, age and education. Smoking was chosen as a marker of health awareness. A total of 65,330 persons participated in the Nord-Trøndelag Health Survey (HUNT-II), performed in 1995-1997. The database of HUNT-II was merged with the Cancer Registry of Norway (CRN), thus identifying each of the 2983 (4 percent) participants with an invasive cancer diagnosis.

RESULTS

Excluding basal cell epithelioma, a total of 20 percent of the patients denied their prior cancer diagnosis. This group consisted mainly of men (54 percent) and those who were diagnosed as very young or as elderly. More smokers than non-smokers were unaware of their prior malignancy (24 percent versus 20 percent).

CONCLUSIONS

A 20 percent rate of patients who denied their former malignancy is surprisingly and unacceptably high. Disclosure of a cancer diagnosis should help the patient to develop increased health awareness. It should enable a person to report his or her former cancer diagnosis when necessary.

Excessive annual BMI increase after chemotherapy among young survivors of testicular cancer

Increased body mass index (BMI) is claimed to be a complication among survivors of testicular cancer (TCSs), especially after receiving cisplatin-based chemotherapy. This study compares changes in BMI (kg m(-2)) in TCSs with those observed in age-matched men from the population (controls). Associations between treatment, age and potential BMI changes were sought. In 1999, a survey was performed at the NRH of 444 unilaterally orchiectomised TCSs treated from 1980 to 1990. BMI at survey was recorded in each TCS. Information on principal treatment (surgery only: SURG; radiotherapy only: RAD; chemotherapy +/- surgery or radiotherapy: CHEM+/-) and pretreatment BMI was retrieved from the medical records. The age-matched controls had BMI measurements from population surveys from 1985 and 1996. The annual BMI increase was calculated based on the difference in the two BMI measurements divided by observation time. TCSs displayed a lower pretreatment mean BMI than the controls, whereas no difference was found post-treatment. However, the annual BMI increase in TCSs exceeded that of the controls (0.19 vs 0.15, P=1.4 x 10(-7)). The SURG and CHEM+/- groups showed the greatest annual BMI increase. The multiple regression analysis showed that young TC patients who received chemotherapy displayed an excessive annual BMI increase. Oncologists and young TCSs should be aware of the risk of excessive BMI increase, in particular, after the use of chemotherapy.

Gastrointestinal presentation of germ cell malignancy

OBJECTIVES

To summarize monoinstitutional experience with gastrointestinal (GI) presentations of germ cell malignancy and to review recent medical literature on this issue.

METHODS

Retrospective review of 5 cases with advanced germ cell malignancy (testicular 2 and retroperitoneal 3) and involvement of the upper GI tract and a comparison with published observation.

RESULTS

In 4 patients the duodenum and in 1 patient the distal part of the esophagus were involved in germ cell malignancy. In 3 patients grade 3 or grade 4 anemia represented the principle initial symptom. Ulceration of the upper GI tract was in 1 case complicated by an aortoduodenal fistula with rupture of the aorta. This patient and 2 other cases needed emergency surgery due to GI hemorrhage before and/or during the initial phase of chemotherapy. Our observations compare well with the literature, showing the need of multimodality therapy of these complications.

CONCLUSION

In young males with a malignant tumor in the upper GI tract, the diagnosis of germ cell malignancy should be considered. Treatment of this condition requires a multimodality approach, not rarely including emergency surgery. Though these patients often belong to a poor-prognosis group, our results and the literature review show that long-term survival is possible using modern treatment principles. In particular, the risk of GI hemorrhage, during the initial phase of therapy, should not be overseen.