Aim Diabetic foot ulcers are associated with an increased risk of death. We evaluated whether ulcer severity at presentation predicts mortality. Methods Patients from a national, retrospective, cohort of veterans with type 2 diabetes who developed incident diabetic foot ulcers between January 1, 2006 and September 1, 2010, were followed until death or the end of the study period, January 1, 2012. Ulcers were characterized as early stage, osteomyelitis, or gangrene at presentation. Cox proportional hazard regression identified independent predictors of death, controlling for comorbidities, laboratory parameters, and healthcare utilization. Results 66,323 veterans were included in the cohort and followed for a mean of 27.7 months: 1-, 2-, and 5-year survival rates were 80.80%, 69.01% and 28.64%, respectively. Compared to early stage ulcers, gangrene was associated with an increased risk of mortality (HR 1.70, 95% CI 1.57 – 1.83, p<0.001). The magnitude of this effect was greater than diagnosed vascular disease, i.e., coronary artery disease, peripheral arterial disease, or stroke. Conclusion Initial diabetic foot ulcer severity is a more significant predictor of subsequent mortality than coronary artery disease, peripheral arterial disease, or stroke. Unrecognized or under-estimated vascular disease and/or sepsis secondary to gangrene should be explored as possible causal explanations.

Patients with diabetes and obesity are at increased risk of developing disturbances in intestinal function. In this study, we characterized jejunal function in the clinically relevant leptin-deficient ob/ob mouse, a model of diabetes and obesity. We measured transepithelial short circuit current (Isc), across freshly isolated segments of jejunum from 12-week-old ob/ob and lean C57BL/6J (female and male) mice. The basal Isc was significantly decreased (~30%) in the ob/ob mice (66.5±5.7 μA/cm2 [n=20]) (P< 0.05) compared with their lean counterparts (95.1±9.1 μA/cm2 [n=19]). Inhibition with clotrimazole (100 μM, applied bilaterally) was significantly reduced in the ob/ob mice (−7.92%±3.67% [n=15]) (P<0.05) compared with the lean mice (10.44%±7.92% [n=15]), indicating a decreased contribution of Ca2+-activated K+ (KCa) channels in the ob/ob mice. Inhibition with ouabain (100 μM, applied serosally) was significantly reduced in the ob/ob mice (1.40%±3.61%, n=13) (P< 0.05) versus the lean mice (18.93%±3.76% [n=18]), suggesting a potential defect in the Na+/K+-adenosine triphosphate (ATP)ase pump with leptin-deficiency. Expression of cystic fibrosis transmembrane conductance regulatory protein (CFTR) (normalized to glyceraldehyde-3-phosphate dehydrogenase [GAPDH]) was significantly decreased ~twofold (P<0.05) in the ob/ob mice compared with the leans, whilst crypt depth was unchanged. Villi length was significantly increased by ~25% (P<0.05) in the ob/ob mice compared with the leans and was associated with an increase in Villin and GLUT5 expression. GLUT2 and SGLT-1 expression were both unchanged. Our data suggests that reduced basal jejunal Isc in ob/ob mice is likely a consequence of reduced CFTR expression and decreased activity of the basolateral KCa channel and Na+/K+-ATPase. Understanding intestinal dysfunctions in ob/ob jejunum may allow for the development of novel drug targets to treat obesity and diabetes.

Cystic fibrosis (CF) results from the loss or reduction in function of the CFTR (cystic fibrosis transmembrane conductance regulatory protein) chloride channel. The third most common CFTR mutation seen clinically is R117H. Genistein, a naturally occurring phytoestrogen, is known to stimulate CFTR function in vitro. We aimed to determine whether route of administration of genistein could mediate differential effects in R117H male and female CF mice. Mice were fed (4 weeks) or injected subcutaneously (1 week) with the following: genistein 600 mg/kg diet (600Gd); genistein-free diet (0Gd); genistein injection 600 mg/kg body weight (600Gi); dimethyl sulfoxide control (0Gi). In male R117H mice fed 600Gd, basal short circuit current (Isc) was unchanged. In 600Gd-fed female mice, there was a subgroup that demonstrated a significant increase in basal Isc (53.14±7.92 μA/cm2, n=6, P<0.05) and a subgroup of nonresponders (12.05±6.59 μA/cm2, n=4), compared to 0Gd controls (29.3±6.5 μA/cm2, n=7). In R117H mice injected with 600Gi, basal Isc was unchanged in both male and female mice compared to 0Gi controls. Isc was measured in response to the following: the adenylate cyclase activator forskolin (10 μM, bilateral), bumetanide (100 μM, basolateral) to indicate the Cl− secretory component, and acetazolamide (100 μM, bilateral) to indicate the HCO3− secretory component; however, there was no effect of genistein (diet or injection) on any of these parameters. Jejunal morphology (ie, villi length, number of goblet cells per villus, crypt depth, and number of goblet cells per crypt) in R117H mice suggested no genistein-mediated difference among the groups. Serum levels of genistein were significantly elevated, compared to respective controls, by either 600Gd (equally elevated in males and females) or 600Gi (elevated more in females versus males). These data suggest a sex-dependent increase in basal Isc of R117H mice and that the increase is also specific for route of administration.

In the ob/ob leptin‐deficient mouse the role of intestinal secretion is unclear. The goal of this study was to characterize jejunal function. We measured transepithelial short circuit current (Isc), across jejunum from ob/ob and lean mice (aged 14 weeks). Basal Isc was significantly decreased in the ob/ob mice (50.5±9.5 μA/cm2, n=5) compared to lean mice (95.2±20.3 μA/cm2, n=4, P<0.05). The Isc in response to forskolin (10 μM, bilateral) was similar in both groups, indicating a comparable cAMP‐dependent Isc. The Isc in response to bumetanide (100 μM, basolateral) and to acetazolamide (100 μM, bilateral) was similar for both groups, indicating analogous Cl− and HCO3− secretory components. Crypt depth was similar for both groups, indicating that structural changes do not contribute towards the reduced Isc of the ob/ob mice. Villi length was significantly increased (~100 μm) in the ob/ob mice, suggesting a greater surface area for absorptive function. Expression of the transporter protein, Glut5 (normalized to GAPDH), was significantly increased 2‐fold in ob/ob mice. These data suggest that basal jejunal Isc in ob/ob mice is ~1/2 that of lean mice, and may reflect a reduced fluidity of the jejunal content in the ob/ob mice, which may contribute to the associated diabetic phenotype. Current studies aim to determine whether the contribution of key epithelial transporters is similarly reduced in the ob/ob mice.

Plantago major (PM), commonly known as common plantain, is a temperate perennial herb. Traditionally, its seeds and leaves have been ingested or applied externally to treat inflammation and infection. Studies showed PM possesses inhibitory effects towards a variety of tumors and cancer cell lines, including mice Ehrlich ascites carcinoma and breast adenocarcinoma, gastric, leukaemia, ovary, melanoma, and renal human cell lines. While PM has been shown to exhibit selective cytotoxic activity against cancer cells, its quantitative potential as a chemopreventive agent on colon cancer has yet to be elucidated. In this study, C57BL/6 mice (N = 30) of 9 wk old were randomized into three groups (N = 10). Positive and experimental mice groups were injected with Azoxymethane (AOM; 5 mg/kg body weight) at the onset and second wk of the 8-wk duration of the in vivo study while the negative group received no injection. The mice in the experimental group were given daily oral feedings of 20 mg/ml of PM from the onset of the study while the negative and positive control groups were given a sterilized water placebo. All groups were sacrificed after 8 wks and 25 mm cuts of the proximal colon were analyzed for aberrant crypt foci (ACF). PM feeding significantly reduced the number of AOM-induced ACF in the proximal colon compared to the water-fed positive control AOM-induced group (7.02 ± 2.61 &lt; 32.1 ± 9.86; P &lt; 0.0003). The negative control, water placebo group had minimal ACF (2.0 ± 1.56) compared to the experimental and positive control groups. The potency index of the herb was calculated as 4.57. Percent inhibition of AOM-induced ACF formation of 78.1% was obtained with the PM treatment. On average, all three groups gained weight (calculated as % increase) through the course of the experiment (experimental, 6.93 &lt; negative control 15.6 &lt; positive control 39.4). Histological (H&E) slides of the proximal colon displayed a significantly higher apoptotic index than the positive control (AOM only) (2.0 &gt; 0.6) and a lower mitotic index (MI) than control (1.5 &lt; 2.8). Caspase 3 induction was identified in human colon cancer cells (COLO-205) treated with PM (5mg/ml) in chamber slides, using a specific carboxyfluorecein (FAM) labeled peptide fluoromethyl ketone (FMK) caspase inhibitor (FAM-Peptide-FMK). Caspase 3 activation was also observed in immunofluorescent slides of PM treated proximal colon tissues. Through inhibition of AOM-induced ACF via apoptosis, our data suggests PM to be a prospective chemopreventive and potential therapeutic agent for colon cancer. Citation Information: Cancer Prev Res 2010;3(12 Suppl):A50.