TLR4 signals through islet macrophages to alter cytokine secretion during diabetes.

Toll-like receptors (TLRs), particularly TLR4, may act as immune sensors for metabolic stress signals such as lipids and link tissue metabolic changes to innate immunity. TLR signalling is not only tissue-dependent but also cell-type dependent and recent studies suggest that TLRs are not restricted to innate immune cells alone. Pancreatic islets, a hub of metabolic hormones and cytokines, respond to TLR signalling. However, the source of TLR signalling within the islet remain poorly understood. Uncovering the specific cell source and its role in mediating TLR signalling, especially within type 2 diabetes (T2D) islet will yield new targets to tackle islet inflammation, hormone secretion dysregulation and ultimately diabetes. In the present study, we immuno-characterised TLRs linked to pancreatic islets in both healthy and obese diabetic mice. We found that while TLRs1-4 and TLR9 were expressed in mouse islets, these TLRs did not co-localise with insulin-producing ß-cells. ß-Cells from obese diabetic mice were also devoid of these TLRs. While TLR immunoreactivity in obese mice islets increased, this was driven mostly by increased islet endothelial cell and islet macrophage presence. Analysis of human islet single-cell RNA-seq databases revealed that macrophages were an important source of islet TLRs. However, only TLR4 and TLR8 showed variation and cell-type specificity in their expression patterns. Cell depletion experiments in isolated mouse islets showed that TLR4 signalled through macrophages to alter islet cytokine secretome. Together, these studies suggest that islet macrophages are a dominant source of TLR4-mediated signalling in both healthy and diabetic islets.

Surgical resection of solitary adrenal metastasis from esophageal carcinoma following esophagectomy.

The prognosis of esophageal carcinoma following esophagectomy is poor due to a high frequency of metastasis to periesophageal lymph nodes and distant organs. However, we experienced a case with good prognosis following resection of a solitary adrenal metastatic tumor. The patient was a 70-year-old man diagnosed with type 2 esophageal cancer (Lt-Ae, T2N1M0, Stage IIB) who was treated with esophagectomy. Eight months following surgery, solitary adrenal metastasis was detected by CT, and was resected. At 42 months follow-up he has had a good quality of life in the community without evidence of recurrence. To the best of our knowledge, only five cases with resected solitary adrenal metastases including our case, have been reported, and show a greater than 1-year survival. Consequently, we suggest that resection of solitary organ metastases is a good alternative, even following esophagectomy.

Tumor stroma as the main source of inhibin production in ovarian epithelial tumors.

PROBLEM: Elevated serum inhibin levels have been found in ovarian cancer patients; however, the source of the elevated inhibin is uncertain. Previous studies of activin in human ovarian cancer suggest that activin may promote the growth of the tumor. The aims of this study were to examine the source of elevated inhibin from ovarian epithelial tumors (OETs) and to preliminarily investigate the role of the gonadotropin-inhibin/activin relationship in the development of OET. METHOD OF STUDY: The protein and mRNA expression of alpha and betaA subunits of inhibin/activin were examined by immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR) in 120 OETs, including 30 benign cystadenomas, 30 borderline tumors, and 60 carcinomas. Stromal and epithelial cells were microdissected from 23 OETs to further examine the expression of alpha and betaA subunits by RT-PCR. Dimeric inhibin A and activin A production were measured by using the two-site ELISA from three OET cell lines in culture under treatment of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). RESULTS: betaA subunit was expressed in the epithelial component of 100% of the cystadenomas, in 80% of borderline tumors, and in 75% of the carcinomas, but not in tumor stroma. Inhibin alpha expression was not found in the epithelium of all OETs studied, but focal inhibin alpha immunoreactivity was seen in the tumor stroma (mainly luteinized stromal cells) in the majority of cases. Dimeric activin A was produced by all of the three OET cell lines with a 1.5-1.9-fold increment after FSH stimulation. However, activin A production was not augmented by LH treatment. No inhibin A was produced by the three OET cell lines with or without gonadotropin stimulation. CONCLUSIONS: The stroma of OET is the major source in the production of inhibin alpha (monomer). Dimeric inhibin A production may be the result of combined efforts of the tumor stroma (alpha subunit) and epithelium (betaA subunit). Cellular, compartmental expression of inhibin and activin subunits may play a role in the development of OET, although the mechanism remains undefined. The unopposed activin A production stimulated by FSH in OET cell lines suggests that activin production may represent one of the cellular mechanisms of growth promotion by FSH.

The effects of oxytocin and vasopressin on partner preferences in male and female prairie voles (Microtus ochrogaster).

This study compared the effects of centrally administered oxytocin (OT) and arginine vasopressin (AVP) on partner preference formation and social contact in male and female prairie voles (Microtus ochrogaster). After 1 hr of cohabitation and pretreatment with either AVP or OT, both males and females exhibited increased social contact and significant preference for the familiar partner. After pretreatment with either an OT receptor antagonist (OTA) or an AVP (V1a) receptor antagonist (AVPA), neither OT nor AVP induced a partner preference. In addition, treatment with OT+OTA or AVP+AVPA was associated with low levels of social contact in both sexes. Either AVP or OT is sufficient to facilitate social contact if either the OT or AVP receptor is available. However, the formation of partner preferences may require access to both AVP and OT receptors.

Estrogen modulates paracellular permeability of human endothelial cells by eNOS- and iNOS-related mechanisms.

Estradiol had a biphasic effect on permeability across cultures of human umbilical vein endothelial cells (HUVEC): at nanomolar concentrations it decreased the HUVEC culture permeability, but at micromolar concentrations it increased the permeability. The objective of the present study was to test the hypothesis that the changes in permeability were mediated by nitric oxide (NO)-related mechanisms. The results revealed dual modulation of endothelial paracellular permeability by estrogen. 1) An endothelial NO synthase (eNOS)-, NO-, and cGMP-related, Ca2+-dependent decrease in permeability was activated by nanomolar concentrations of estradiol, resulting in enhanced Cl- influx, increased cell size, and increases in the resistance of the lateral intercellular space (RLIS) and in the resistance of the tight junctions (RTJ); these effects appeared to be limited by the ability of cells to generate cGMP in response to NO. 2) An inducible NO synthase (iNOS)- and NO-related, Ca2+-independent increase in permeability was activated by micromolar concentrations of estradiol, resulting in enhanced Cl- efflux, decreased cell size, and decreased RLIS and RTJ. We conclude that the net effect on transendothelial permeability across HUVEC depends on the relative contributions of each of these two systems to the total paracellular resistance.

Effects of estrogen on tight junctional resistance in cultured human umbilical vein endothelial cells.

OBJECTIVE: To study the effects of estrogen on transendothelial paracellular permeability in women. METHODS: Human umbilical vein endothelial cells (HUVEC) obtained from women were grown on filters. The paracellular permeability characteristics were determined in terms of changes in the permeability to the polar acid pyranine (Ppyr) and as changes in the transendothelial electrical resistance (RTE). Tight junctional resistance characteristics were assayed by lowering luminal NaCl and measuring the dilution potential, and were expressed as the ratio of monoion mobility uCl/uNa (cation selectivity). RESULTS: Low extracellular calcium and hyperosmolarity increased Ppyr and decreased RTE. The former but not the latter condition abolished the endothelium-specific cation selectivity. Treatment with 10 nM of estradiol-17 beta had no effect on RTE, but it increased the cation selectivity. The effect of estradiol required 1-6 hours' incubation with the hormone; it was dose dependent and saturable, with a median effective concentration of estradiol of 1 nM. Diethylstilbestrol, but not estriol, could mimic the effect of estradiol, and the estrogen receptor antagonist ICI-182, 780 blocked it. CONCLUSION: Cultured HUVEC cells form patent tight junctions. Estrogens increase the cation selectivity across HUVEC cultures. The effect of estrogen may be mediated by an estrogen receptor. These effects may be important for vasculoprotection in cases of sudden changes in ions levels across the capillary wall, such as ischemia or reperfusion.

In vitro cytokine modulation of intercellular adhesion molecule-1 expression on systemic sclerosis dermal fibroblasts.

Our objective was to study the regulation of intercellular adhesion molecule-1 (ICAM-1) expression by cytokines on cultured fibroblasts obtained from systemic sclerosis and normal skin. ICAM-1 expression on dermal fibroblasts obtained from diffuse systemic sclerosis patients with early disease (< or = 2 years) and normal dermal fibroblasts incubated with and without cytokines was measured by radioimmunoassay and flow cytometry. Systemic sclerosis dermal fibroblasts expressed lower basal levels of ICAM-1 than did normal dermal fibroblasts. Both the normal and systemic sclerosis dermal fibroblasts increased their cell surface expression of ICAM-1 in response to interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) in a dose-dependent fashion. Systemic sclerosis dermal fibroblasts appeared to be hyperresponsive to IL-1 beta, TNF-alpha, and IFN-gamma. ICAM-1 expression in response to cytokine stimulation increased to a greater degree on systemic sclerosis compared to normal dermal fibroblasts. The enhanced ICAM-1 expression may play a role in the retention of leukocytes involved in systemic sclerosis skin lesions.

Serum LH levels in the differential diagnosis of hirsute anovulatory women.

Polycystic ovarian syndrome (PCO) occurs frequently in hirsute patients. A dissociated explosive response of LH to LHRH administration has been associated with the diagnosis of PCO. Twenty-four of 58 women seen because of hirsutism were found to have ovarian dysfunction based on clinical signs such as anovulation and irregular menstrual cycles. Plasma androgen levels were elevated in the patient group. The LHRH test (200 micrograms, iv) was applied to the 24 patients and compared with 13 normal ovulatory controls. Serum FSH levels before and after the LHRH test were normal in all patients. Two patterns of LH response to LHRH stimulation were observed: an explosive response in 17 patients (delta LH: 39.4 +/- 21.8 IU/l, control group: 7.35 +/- 4.4 IU/l, P < 0.01) and a normal response in 7 patients (delta LH: 7.53 +/- 2.41 IU/l). There was a significant correlation (r = 0.63, P < 0.05) between basal LH levels and LH response to LHRH. Sensitivity and specificity calculated for basal LH levels higher than 6.0 IU/l, considering the LHRH test as reference, were 58% and 85%, respectively. The positive predictive value measuring the possibility of LH higher than 6.0 IU/l to be from a patient with PCO (explosive response to LHRH) was 92%. These data suggest that, in hirsute anovulatory patients, basal LH levels may be a good predictor in the diagnosis of polycystic ovarian syndrome.

Serum LH levels in the differential diagnosis of hirsute anovulatory women

Polycystic ovarian syndrome (PCO) occurs frequently in hirsute patients. A dissociated explosive response of LH to LHRH administration has been associated with the diagnosis of PCO. Twenty-four of 58 women seen because of hirsutism were found to have ovarian dysfunction based on clinical signs such as anovulation and irregular menstrual cycles. Plasma androgen levels were elevated in the patient group. The LHRH test (200 micrograms, iv) was applied to the 24 patients and compared with 13 normal ovulatory controls. Serum FSH levels before and after the LHRH test were normal in all patients. Two patterns of LH response to LHRH stimulation were observed: an explosive response in 17 patients (delta LH: 39.4 +/- 21.8 IU/l, control group: 7.35 +/- 4.4 IU/l, P < 0.01) and a normal response in 7 patients (delta LH: 7.53 +/- 2.41 IU/l). There was a significant correlation (r = 0.63, P < 0.05) between basal LH levels and LH response to LHRH. Sensitivity and specificity calculated for basal LH levels higher than 6.0 IU/l, considering the LHRH test as reference, were 58 per cent and 85 per cent , respectively. The positive predictive value measuring the possibility of LH higher than 6.0 IU/l to be from a patient with PCO (explosive response to LHRH) was 92 per cent . These data suggest that, in hirsute anovulatory patients, basal LH levels may be a good predictor in the diagnosis of polycystic ovarian syndrome

In situ expression of cytokines and cellular adhesion molecules in the skin of patients with systemic sclerosis. Their role in early and late disease.

Cytokines and cellular adhesion molecules (CAMs) may play a role in the inflammatory and fibrotic processes underlying systemic sclerosis (SSc). We compared the immunohistological distribution of cytokines and CAMs in skin biopsies from 12 SSc patients and 14 normal (NL) individuals. Among CAMs, vascular cell adhesion molecule-1 (VCAM-1), which mediates leukocyte-endothelial adhesion, showed increased expression on SSc versus NL endothelium and stratum granulosum. P-selectin was up-regulated in SSc versus NL stratum granulosum. The CD44 lymphocyte homing receptor showed the most striking differences between SSc and NL: its expression was increased in SSc stratum granulosum, stratum spinosum, on lymphocytes, and macrophages. Regarding cytokines, interleukin-6 (IL-6) expression was increased on SSc versus NL endothelium and fibroblasts. Tumor necrosis factor-alpha (TNF-alpha) reactivity was more prevalent in SSc than NL stratum granulosum, whereas IL-8 expression was higher on SSc compared to NL endothelium. Some CAMs, such as VCAM-1 and P-selectin, and cytokines, namely TNF-alpha and IL-8, were more commonly found in skin biopsies taken from early (< or = 1 year's duration) SSc, while others, such as IL-6, showed up-regulation in the late stage of the disease. The results suggest that certain CAMs and cytokines may play a differential role in both the early, inflammatory, and the late, fibrotic stage of SSc.

The ontogeny of pulmonary defenses: alveolar macrophage function in neonatal and juvenile rhesus monkeys.

Using the technique of bronchoalveolar lavage, we isolated alveolar macrophages (AM) from the lower respiratory tract of newborn (1-4 days of age), infant (6-10 days of age), juvenile (3-6 months of age), and adult rhesus monkeys. The AM thus obtained were assayed in vitro to determine their chemotactic, phagocytic, and candidicidal capabilities. The predominant (greater than or equal to 89%) cell type in bronchoalveolar lavage effluent in all ages was the AM. Chemotaxis, phagocytosis, and killing of Candida albicans were markedly impaired in neonatal AM as compared with those from infants, juveniles, and adults. AM chemotactic activity achieved normal adult values by 6 days of age. Phagocytosis, and to a lesser extent candidicidal activity, were significantly improved in 6-day-old animals, but adult levels were still not achieved even by 6 months of age.

Comparison of human growth hormone levels in children with satisfactory and unsatisfactory growth.

Sixty-six children with satisfactory growth and 73 with unsatisfactory growth (both sexes) from three different age groups (1 year, 5 years and 10 years) were included in this study. It was observed that the serum concentrations of human growth hormone (hGH) in children with satisfactory growth ranged from 1.00 to 4.00 ng/ml and never exceeded 4.00 ng/ml. In a comparative study there was a significant increase in serum hGH levels in subjects of all age groups who were not growing satisfactorily. Twelve children between 12 and 13 months of age with unsatisfactory growth were nutritionally rehabilitated for 4 months and the changes in weight and serum hGH levels were assessed monthly. The results indicated a definite fall of hGH level after rehabilitation and reached the normal level 3 months after rehabilitation. Moreover, an inverse relationship between body weight and serum hGH level was observed.

Variability of daily creatinine excretion in healthy adults.

In order to determine the within-subject variability of creatinine excretion, the 24-h output was measured over 5 consecutive d in 12 subjects. The mean within-subject coefficient of variation was 3.6 per cent. There was much greater variation between subjects. The creatinine excretion in g/d was 30-40 per cent lower in Burmese subjects than in Europeans and North Americans, but the excretion per kg was slightly higher, suggesting that the Burmese are more muscular.