Upregulation of pituitary adenylate cyclase activating polypeptide and its receptor expression in the rat carotid body in chronic and intermittent hypoxia.

The carotid body (CB) plays important roles in cardiorespiratory changes in chronic and intermittent hypoxia. Pituitary adenylate cyclase activating polypeptide (PACAP) is involved in the regulation of respiratory chemoresponse. We hypothesized an upregulation of the expressions of PACAP and its receptor (PAC1) in the rat CB in chronic and intermittent hypoxia. The CB expressions of PACAP and PAC1 were examined in rats breathing 10% O(2) (in isobaric chamber for chronic hypoxia, 24 h/day) or in intermittent hypoxia (cyclic between air and 5% O(2) per minute, 8 h/day) for 7 days. Immunohistochemical studies showed that the PACAP and PAC1 proteins were localized in CB glomic clusters containing tyrosine hydroxylase. The proportional amount of cells with positive staining of PACAP and PAC1 was significantly increased in both hypoxic groups when compared with the normoxic control. In addition, the mRNA level of PAC1 expression was markedly elevated in the hypoxic groups, despite no changes in the PACAP expression. These results suggest an upregulation of PACAP and its receptor expression in the rat CB under chronic and intermittent hypoxic conditions. The PACAP binding to its receptor could activate the PKA signaling pathway leading to an increased CB excitability under hypoxic conditions.

Upregulation of erythropoietin and its receptor expression in the rat carotid body during chronic and intermittent hypoxia.

The carotid body (CB) plays important roles in cardiorespiratory changes in intermittent hypoxia (IH). Erythropoietin (EPO), a hypoxia-inducible factor (HIF)-1 target gene, is present in the chemoreceptive type-I cells in the CB but its expression and role in IH resembling sleep apnoeic conditions are not known. We hypothesized that IH upregulates the expression of EPO and its receptor (EPOr) in the rat CB. The CB expressions of EPO and EPOr were examined in rats breathing 10% O(2) (in isobaric chamber for CH, 24 hour/day) or in IH (cyclic between air and 5% O(2) per minute, 8 hour/day) for 3-28 days. Immunohistochemical studies revealed that the EPO and EPOr proteins were localized in CB glomic clusters. The proportional amount of cells with positive staining of EPO immunoreactivities was significantly increased in both IH and CH groups when compared with the normoxic control. The EPO expression was more markedly increased in the CH than that of the IH groups throughout the time course, reaching a peak level at day 14. The positive EPOr immunostaining was increased significantly in the 3-day CH group. By day 14, the EPOr expression elevated considerably at peak levels in both IH and CH rats, whereas the elevation was greater in the CH rats. These results suggest an upregulation of EPO and its receptor expression in the rat CB under IH and CH conditions, presumably mediated by the activation of HIF-1 pathway. The increased EPO binding to its receptor might play a role in the enhancement of CB excitability during the early pathogenesis in patients with sleep-disordered breathing.

Effects of combination of angiotensin-converting enzyme inhibitor and angiotensin receptor antagonist on inflammatory cellular infiltration and myocardial interstitial fibrosis after acute myocardial infarction.

OBJECTIVES: The goal of this study was to compare the relative efficacy of an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin receptor blocker (ARB) in suppressing the histopathologic changes that lead to ventricular remodeling after an acute myocardial infarction (AMI). BACKGROUND: Myocardial interstitial fibrosis in the noninfarcted region is a major histologic landmark resulting in cardiac dysfunction after AMI. However, the relative potency of an ACE inhibitor and ARB on suppressing the histopathologic changes was unclear. METHODS: Rats with AMI were randomized to fosinopril, valsartan or a combination of the two drugs for two or four weeks. The total, type I and type III collagen and activated fibroblasts and macrophages were quantified by histomorphometry. The expression of transforming growth factor-beta 1 (TGF-beta 1) messenger ribonucleic acid (mRNA) was determined by reverse transcription polymerase chain reaction. RESULTS: Acute myocardial infarction resulted in significant elevation of total (p < 0.001) and type I (p < 0.001) collagen and a twofold increase in TGF-beta 1 mRNA expression (p < 0.001) in the septum at two and four weeks. Macrophages and activated myofibroblasts infiltrated extensively in the infarct zone. Treatment with valsartan or combination therapy normalized the total and type I collagen (p < 0.001) as well as TGF-beta 1 mRNA level (p < 0.01) in the septum and was associated with the suppression of macrophages and myofibroblasts in the infarct zone (p < 0.01). Fosinopril was less effective than valsartan or combination therapy. CONCLUSIONS: The use of valsartan, especially combined with fosinopril, was more effective than fosinopril in the suppression of histopathologic changes resulting in cardiac remodeling after AMI. This study has important therapeutic implications in pharmacotherapy of clinical practice.

Macrophage migration inhibitory factor expression in male and female ethanol-fed rats.

Macrophage migration inhibitory factory (MIF) regulates macrophage accumulation at sites of injury and can promote the inflammatory response. We studied MIF expression in the intragastric feeding rat model for alcoholic liver injury. Male and age-matched female rats were fed ethanol or dextrose with fish oil. Two groups of male rats were fed medium-chain triglycerides with ethanol or dextrose. Analysis of liver histopathology, lipid peroxidation, endotoxin, mRNA, and immunohistochemistry for MIF, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were carried out. Male and female rats fed fish oil and ethanol showed necroinflammatory liver injury and had the highest expression of MIF, TNF-alpha, and IFN-gamma in the liver. Decreased levels of MIF protein were seen in rats with higher endotoxin levels, suggesting that preformed MIF is released into the circulation. MIF is an important mediator of the inflammatory response in alcoholic liver disease and a potential therapeutic target.

Induction of apoptosis by hexamethylene bisacetamide is p53-dependent associated with telomerase activity but not with terminal differentiation.

The present study investigated the relationships amongst apoptosis, terminal differentiation and telomerase activity in human colon carcinoma cells. We found that hexamethylene bisacetamide (HMBA) induced apoptosis in human colon carcinoma LoVo cells harbouring wild-type p53 but not in SW1116 cells harbouring mutant p53. HMBA reduced telomerase activity in both colon carcinoma cells but it did not induce differentiation in the colon carcinoma cells. Taken together, our results suggest that HMBA can induce apoptosis via a p53-dependent pathway, but apoptosis and terminal differentiation may be separately regulated in LoVo cells. Inhibition of telomerase activity may activate apoptosis through a p53-dependent mechanism.

Blood vessel morphometry in human colorectal lesions.

Neovascularisation in tumours of different cell origins has been well documented qualitatively. In this report, we have assessed vascular architecture in different pathological lesions of the colorectum by quantifying blood vessel parameters in order to detect subtle morphological changes using objective methods. Colorectal tissue samples were obtained from resected large bowels containing malignant tumours. Biopsies were taken from defined sites in the resected specimen and were classified as normal (N), potentially premalignant mucosa (PPM), adenomatous polyp (P) and adenocarcinoma (ADCA). All tissues were fixed in modified Karnovsky's fixative for 4 hrs and postfixed in 1% OsO4 for 1 hr. Samples were processed for EM under standardized procedures and embedded in Epon. 0.5 microns semithin sections from five patients per group were stained with toluidine blue. A multistage systematic sampling procedure was adopted. The inner outlines of all blood vessels in the lamina propria (LP) were digitised using a Zeiss VIDAS Image Analyzer at a final magnification of x1,050. The area of the reference (LP) was also measured. No attempt was made to distinguish between the different types of vessel. The morphometric blood vessels parameters quantified were volume density (Vv), numerical density (NA), length density (LV) and mean transverse sectional area (A). Statistically significant differences in Vv and A were detected between all groups except between N and PPM and between P and ADCA. No significant differences in NA and LV were present in any group comparisons. The mean values of all parameters were the highest in ADCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitative assessment of normal and potentially premalignant epithelium at different levels of human colorectal crypts.

The present study uses morphometric techniques to assess whether altered differentiation patterns exist in PPM which might reflect its premalignant status. Samples were obtained from resected malignant lesions of large bowels of 10 Chinese patients. Normal (N) samples were biopsied from the margins of each resected large bowel. Potentially premalignant (PPM) mucosae were obtained from within 2 cm of the margins of the malignant lesions. Tissues were processed for histological examination and using strict criteria, colorectal crypts were divided into basal (B), intermediate (I) and surface (S) segments. Interactive digitisation of sections from each group was used to generate the following morphometric parameters in each segment: nuclear profile circularity indices (NSF and NCI); nuclear numerical density (NA and NV); the degree of deviation of the major nuclear axis in relation to the epithelial-connective junction (AGDMAX); cell height (CH); the distance between nuclear apex to cell apex (DNACA); the distance between cell base to nuclear apex (DCBNA); stratification index (SI)--the ratio of DCBNA and CH; and the volume density of mucous vacuoles in the reference epithelium (VVMV,EP). In comparisons of different segments within groups, the nuclei at the S segment of N and PPM crypts were more irregular and less circular in shape than nuclei from other segments. There was a shift of nuclear profile shape (NSF and NCI) from circular to ellipsiodal between B and S segments. In comparisons of similar segments between groups, no significant nuclear shape changes were detected in nuclei of PPM crypts when compared with nuclei in similar segments of N crypts and the pattern of nuclear shape alterations resembled those of normal crypts. In comparisons of different segments within groups of N and PPM crypts, AGDMAX, DNACA, DCBNA, CH and SI parameters demonstrated that epithelial cells at the I segments have more centrally positioned nuclei with the tallest epithelial height when compared with epithelial cells in other segments of both crypts. In B segments, nuclear NA and NV were almost double those of other segments in both N and PPM crypts, with marked reductions in these parameters between B and I segments. VVMV,EP was significantly highest in the I segment and significantly lowest in the S segment of both groups. Both N and PPM crypts showed similar trends in VVMV,EP within the crypt segments but when comparing similar segments between both crypts, a significant difference was detected only between S segments. The alterations of nuclear shape and packing densities, orientation and mucous content in N crypts were similarly expressed in PPM crypts and distinct differences in numerical density (NV) and stratification index existed in crypts between these two groups when comparing similar segments. All values in PPM were consistently lower when compared with N crypts. These preliminary observations may represent a subtly altered state of cellular differentiation in PPM which may be a reflection of early preneoplastic transformation.

Transcriptional mRNA of BMP-2, 3, 4 and 5 in trigeminal nerve, benign and malignant peripheral nerve sheath tumors.

The aim of our study was to document whether relationships existed among bone morphogenetic proteins (BMPs), peripheral nerve and neoplastic lesions of nerve sheath tumors. The mRNA transcriptions of BMP-2, 3, 4 and 5 in 10 cases of schwannoma, three cases of malignant schwannoma and two cases of trigeminal neuralgia were detected using an in situ hybridization technique. Our results demonstrated that the myelin sheaths of Schwann cell from the peripheral neuroectomy of trigeminal neuralgia positively expressed mRNA of BMP-2, 3, 4, and 5. The most interesting finding was that the nerve fibers of trigeminal nerve showed only BMP-2 positive staining. All of the neoplastic lesions of nerve sheath showed a consistent but variant expression of BMP-2, 3, 4, and 5. The expression signals of BMP-2, 3, 5 mRNA in malignant schwannoma were relatively lower than in benign lesions except for the expression of BMP-4 mRNA. Our results indicated that selected members of BMPs were expressed in the peripheral nerves that might contribute to the health maintenance, proliferation, regeneration and neoplastic transformation of the peripheral nerve system. Furthermore, the effects of BMP-2, 3, 4 and 5 on peripheral nervous system during neoplastic transformation might be widespread, diverse and antagonistic.

Overexpression of iNOS and down-regulation of BMPs-2, 4 and 7 in retinoic acid induced cleft palate formation.

The present work studied the induction of cleft palate formation in embryos developed from pregnant BALB/c mice treated orally with retinoic acid (RA). Previous studies on mature somatic cell types showed that RA exerted inhibitory effects on inducible nitric oxide synthase (iNOS) production. For the first time, our study has shown that RA actually stimulates significant expression of iNOS at specific zones of the affected embryonic palatal tissues at three consecutive stages, from gestation day 13 (GD13) to day 16 (GD16). Enzymatically, iNOS facilitates intracellular nitric oxide (NO) synthesis from L-arginine. When NO reacts with reactive superoxides it may result in irreparable cell injury. NO was also reported to induce apoptosis in some mammalian cell systems. Based on our findings, we propose that such an increase in NO production might be associated with apoptosis in the embryonic palatal tissues in the RA-treated mice. The detrimental effects of NO resulted in a reduction in proliferating palatal cells and therefore disturbed the normal plasticity of the palatal shelves. With iNOS overexpression, our findings also showed that there was significant concomitant down-regulation in the expressions of Bone Morphogenetic Proteins (BMPs) -2, 4, and 7 with regional variations particularly in the palatal mesenchymal cells for those embryos developing cleft palate. Since specific spatial and temporal expressions of BMPs -2, 4, and 7 are critical during normal palatal morphogenesis, any deficiency in the epithelial-mesenchymal interaction may result in retarding growth at the embryonic palatal shelves. Taken together, our study has demonstrated cleft palate formation in the BALB/c embryos involved overexpression of iNOS and down-regulation of BMPs-2, 4 and 7.

A quantitative investigation of immunocytochemically stained blood vessels in normal, benign, premalignant and malignant human oral cheek epithelium.

The present study was designed to determine whether increased vascularity occurs during malignant transformation of human oral cheek epithelium. Nine normal (N) samples were taken from the resection margins of benign lesions; the pathological lesions were classified as chronic inflammation (CI; n = 11), fibrous hyperplasia (FH; n = 12), lichen planus (LIP; n = 8), dysplasia (DYS; n = 5), squamous cell carcinoma (SCC; n = 25; well differentiated [SCCWD]; n = 10; moderately to poorly differentiated [SCCMPD]; n = 15) and epithelium adjacent to carcinomas (EAC; n = 6). Sections were stained with monoclonal antibody (mAb) against vimentin using an ABC immunoperoxidase technique. All blood vessels present within a depth of 0.9 mm of lamina propria were quantified irrespective of their morphology. The blood vessel parameters quantified were volume density (VVBV, CT), number per unit area (NABV, CT), length per unit volume (LVBV, CT) and mean transverse sectional area (ABV). VVBV, CT increased significantly between normal and all pathological groups. Amongst the pathological groups, statistical differences were detected between CI and SCC, CI and EAC, FH and SCCWD, FH and EAC, LIP and SCC, LIP and EAC, DYS and SCCWD and DYS and EAC. The EAC group had the highest VVBV, CT and the values of NABV, CT and LVBV, CT were significantly higher in all the pathological groups when compared with the normal group. No significant differences were detected between any of the pathological group. The parameter ABV increased significantly between normal and DYS, FH, SCC, EAC, FH and EAC, FH and SCC, CI and EAC, CI and SCC, LIP and EAC and LIP and SCC. Spearman rank correlations detected a positive correlation between the severity of oral lesions and all of the blood vessel parameters. We conclude that a mAb against vimentin improved the identification of smaller blood vessels and the blood vessel data suggest that angiogenesis occurs in premalignant and malignant lesions of human oral cheek epithelium. Angiogenesis seems to play an essential role in sustaining the actively growing and transforming cells.

Bronchiectasis: not an orphan disease in the East.

Bronchiectasis is a common disease in the developing world. While the aetiology of bronchiectasis is diverse, many patients suffer from idiopathic disease. Although the pathogenesis of bronchiectasis is poorly understood, there are three distinct pathogenic elements, namely infection, inflammation and enzymatic actions. These interact to perpetuate airway destruction in many cases. There are four patient stereotypes: rapidly progressive, slowly progressive, indolent disease and haemoptysis-predominant. The diagnosis of bronchiectasis is best made with high resolution computed tomography, which should be followed by delineation of aetiology and evaluation of disease severity. Management of bronchiectasis is unsatisfactory and there are no disease-modifying drugs or treatment guidelines. Specific therapy to correct an underlying defect should be instituted whenever possible, although established disease often continues to deteriorate relentlessly. Treatment with prolonged, high-dose antibiotics is useful for exacerbations and probably also for some severely affected patients with frequent exacerbations who habour Pseudomonas aeruginosa in their airways. Commencement of long-term nebulised aminoglycoside, elective in-patient intravenous antibiotic therapy, long-term oral antibiotic or low-dose macrolide therapy requires special considerations. Inhaled corticosteroid therapy reduces chemokine expression in bronchiectasis in vivo, and may be useful for some patients. For severely affected patients, the use of non-invasive positive-pressure ventilation with supplementary oxygen sometimes helps. The lack of enthusiasm about bronchiectasis has already resulted in a lack of research in the treatment of this frustrating disease, and such research needs to be encouraged.

Exhaled nitric oxide in bronchiectasis: the effects of inhaled corticosteroid therapy.

SETTING: While exhaled nitric oxide (eNO) levels are reduced by inhaled corticosteroid therapy in asthma, such treatment effect is unclear in bronchiectasis. DESIGN: Stable non-smoking bronchiectasis patients were randomised to receive either fluticasone (1 mg/daily) or identical placebo via the Accuhaler device. RESULTS: Sixty non-smoking patients (38 women; mean age 56.4 +/- 12.7 years) were recruited. Of these, half received inhaled fluticasone and half placebo therapy. eNO was measured using a chemiluminescence analyser at 0, 4, 12, 24, 36 and 52 weeks. There was no significant difference in eNO levels between fluticasone and placebo patients over the study period. There was no correlation between baseline eNO with age, FEV1, FVC, 24 h sputum volume or number of bronchiectatic segments. Patients with Pseudomonas aeruginosa (PA) infection, but not their counterparts, displayed a correlation between 0- and 52-week eNO levels. PA infection was associated with significantly lower eNO levels among the patients. CONCLUSIONS: Inhaled fluticasone therapy, despite being an effective anti-inflammatory agent, has no significant effect on eNO production, either at individual time points or over the entire 52-week profile, in bronchiectasis. It appears that eNO might not reflect the extent of airway inflammation in bronchiectasis.

The assessment of proliferating cell nuclear antigen (PCNA) immunostaining in human benign and malignant epithelial lesions of the parotid gland.

Immunoreactivity of proliferating cell nuclear antigen (PCNA) was assessed in formalin-fixed, paraffin-embedded sections from human normal parotid gland (N; n = 12), chronic sialadenitis (CS; n = 8), Warthin's tumour (W; n = 10), benign pleomorphic adenoma (BPA; n = 11), mucoepidermoid carcinoma (MEC; n = 14), carcinoma in pleomorphic adenoma (CPA; n = 10) and adenoid cystic carcinoma (ACC; n = 12) of the parotid gland, using the monoclonal antibody PC 10. The morphometric parameters measured comprised PCNA labelling induces (PI = the numerical percentage of PCNA positive nuclei) and volume densities of PCNA positive nuclei(VV, PEP = the relative volume of positive nuclei per unit volume of reference epithelium). All parameters were expressed in relation to total positive, as well as to strongly- and weakly-positive nuclei. In general, the values of PCNA parameters increased progressively in benign lesions in comparison with the N group, and in malignant neoplasms in comparison with non-neoplastic groups and benign lesions. The strongly-positive parameters showed more statistically significant differences than weakly-positive ones, suggesting that weakly-stained nuclei may include some non-cycling cells and, therefore, that weakly-positive parameters may not be reliable proliferation markers. Values for all parameters in CPA were significantly higher than those in BPA, suggesting that these parameters may be used as diagnostic discriminators. Spearman rank correlation analysis showed a highly positive correlation between the morphometric parameters and the severity of the lesions. Furthermore, the mean values of PISP were significantly higher in patients who died of the malignant tumours than in those patients who survived. Our results indicate that PCNA indices might be useful markers for discriminating between benign (BPA) and malignant tumours of the parotid gland and that the parameter PISP may have prognostic applications.

Overexpression of BMP-2/4, -5 and BMPR-IA associated with malignancy of oral epithelium.

The aim of the present study was to determine the relationships between bone morphogenetic proteins (BMPs), BMP receptor type IA and carcinogenesis of oral epithelium. A retrospective study was performed on material obtained from oral mucosa, including nine cases of normal mucosa (NB), eight cases of nonspecific chronic inflammation (NCI), seven cases of hyperkeratosis (HK), five cases of squamous cell papilloma (SCP), 29 cases of squamous cell carcinoma (SCC) with various grades of differentiation and 10 cases of epithelium adjacent to carcinoma (EAC). Six cases of NB from hard palate (NHP) were chosen as a control group. The benign groups consisted of NCI, HK and SCP. The antibodies against BMP-2/4, -5, receptor BMPR-IA and purified bovine BMP (bBMP-McAb) were utilised using an immunocytochemical method. The results demonstrated that the immunostaining of BMP-2/4, BMP-5, BMPR-IA and bBMP-McAb was weak and not consistent in normal and benign groups. The immunoreactivity level was independent of the clinical and pathological grading of SCC. All cases of SCC showed positive staining for BMP-2/4, BMP-5, BMPR-IA and bBMP-McAb except for three cases and one case of SCC which negatively stained for BMP-2/4 and BMP-5, respectively. The staining intensity and proportion of the positively stained cells were markedly increased in SCC when compared with that of the normal and benign groups except for EAC. The metastatic carcinoma cells in lymph nodes were strongly and positively stained for BMP-2/4 and BMP-5 when compared with the primary lesions. Our results indicate that there was an overexpression of BMP-2/4, BMP-5, bBMP-McAb and BMPR-IA in the high-risk premalignant and malignant lesions of oral epithelium. Our findings suggest that BMP-2/4 and BMP-5 but not BMPR-IA might be involved in the metastasis of oral carcinoma cells.

p53 oncoprotein accumulation in adenoid cystic carcinoma of parotid and palatine salivary glands.

Previous studies have suggested that alterations of the p53 gene are the most common genetic abnormality in human cancer. The aims of the present study were to evaluate p53 protein (p53P) immunostaining in adenoid cystic carcinoma (ACC) of the salivary gland and to correlate the expression with patient survival. A total of 27 cases of ACC in the parotid gland (n = 12) and the minor palatine glands (n = 15) were studied, with ten cases each of normal parotid and palatine glands as non-neoplastic controls. Staining was performed with mouse monoclonal antibody DO-7 against p53 (Dako, USA) using the ABC method. Stained nuclei irrespective of intensity or frequency were considered as positive. The frequency of positive nuclei was evaluated as the p53P index (p53PI), the percentage of the total nuclei in the reference epithelium. Clinical survival data were available for patients for periods up to 156 months. Our data showed that no normal tissues showed immunoreactivity with p53P in their nuclei. Thirteen of 15 (87%) cases of palatal and two of 12 (17%) cases of parotid neoplasms stained with p53P and the p53PI ranged from 0.01 to 10%. The number of p53P positive tumors was significantly higher in palatal than in parotid neoplasms, suggesting that palatal ACCs may be more aggressive in comparison with parotid ACCs. Our data also showed that the number of p53P positive tumors was significantly increased in patients who died of tumors than in patients with no evidence of disease at the end of the follow-up period between 60 to 156 months. These results suggest that p53P may be involved in the development of salivary gland ACCs and that p53P analysis may be a useful indicator of poor prognosis.

Macrophages, neutrophils and tumour necrosis factor-alpha expression in bronchiectatic airways in vivo.

Bronchiectasis is increasingly being recognized as an inflammatory condition of the airways in which pathological permanent dilation occurs. We have obtained endobronchial biopsies in 14 patients with stable bronchiectasis and 15 control subjects. Airway neutrophils, macrophages and tumour necrosis factor-alpha (TNFalpha)-positive cells were stained with monoclonal antibodies and the densities of positive cells in the lamina propria were determined by using a computer image analyser. There was significantly higher neutrophil, macrophage and TNFalpha-positive cell densities in the lamina propria of bronchiectatic than control airways (P < 0.001, P < 0.001 and P=0.0002, respectively). Airway neutrophil density in bronchiectasis but not in controls, correlated with TNFalpha-positive cell density (r=0.71, P=0.004). A significant correlation between airway macrophage and TNFalpha-positive cell densities was demonstrated in both control and bronchiectatic airways (r=0.63, P=0.016 and r=0.60, P=0.02 respectively). Neutrophil density negatively correlated with per cent forced vital capacity (FVC%) predicted among patients with bronchiectasis (r=-0.53, P=0.04). Bronchiectasis patients who were regular sputum producers had a significantly higher macrophage, but not neutrophil density than their counterparts (P=0.02 and P=0.48 respectively). Our original findings suggest that airway macrophages could contribute to neutrophil influx into airway walls through their production of TNFalpha and therefore play an important role in the pathogenesis of bronchiectasis.

Down-regulation of aquaporin 3 in bronchiectatic airways in vivo.

Bronchiectasis is characterized pathologically by permanent abnormal bronchial dilation, and clinically by chronic sputum production. Aquaporin 3 (AQP3), a recently described water channel that is also found in large airway cell membrane, could play a role in the pathogenesis and particularly that of bronchorrhea in bronchiectasis. However, little is known of its in vivo distribution and physiological role in human airways. We have, therefore, performed this quantitative immunohistochemistry study on endobronchial biopsies to evaluate the expression and clinical relevance of AQP3 in patients with idiopathic bronchiectasis (n = 25, 15 F, 64.3 +/- 11.5 years) and control subjects (n = 14, 5 F, 57.5 +/- 12.0 years). Quantitative image analysis was performed to evaluate the expression of AQP3 in the bronchial epithelial cells. Our results show that AQP3 was predominantly expressed in the basal cells of the epithelial layer in both groups. Expression of AQP3 was significantly reduced in the basal, but not columnar, epithelial cells in bronchiectasis compared with control airways (p = 0.02, 0.35). Only bronchiectatic patients with regular sputum production, but not their counterparts, had significant downregulation of epithelial AQP3 expression compared with control airways (p = 0.004, 0.24). Our findings suggest that AQP3 could have an important role in the pathogenesis of increased mucus production in bronchiectasis.

Alteration in the expression of bone morphogenetic protein-2,3,4,5 mRNA during pathogenesis of cleft palate in BALB/c mice.

To identify the function of these bone morphogenetic proteins (BMP) during pathogenesis of cleft palate, an experimental model was established in BALB/c mice. Cleft palate was induced by exposure to retinoic acid on embryonic day (E)12. The expression of BMP-2,3,4,5 mRNA in normal and abnormal embryonic palatal shelves was then examined from E13 to E16 by in situ hybridization. The results showed that BMP-4 mRNA was expressed strongly and uniformly in normal epithelial cells and dispersed mesenchymal cells on E13. BMP-2,5 mRNA expression appeared only in dispersed mesenchymal cells. With the development of shelves, the staining density of BMP-2,4,5 decreased gradually in mesenchymal cells outside of the condensation and increased inside the condensation. After shelves had fused on E16, no positive signals for BMP-2,4,5 were detected in dispersed mesenchymal cells, but their expression persisted in the condensation. Exposure to retinoic acid delayed the formation of the condensation and decreased BMP-2,4,5 mRNA dramatically in mesenchyme from E13 to E15. BMP-3 mRNA expression were almost negative in either control or retinoic acid-treated groups during all stages. It was concluded that spatial and temporal expression of BMP-2,4,5 was required during normal palatogenesis, and that a deficiency of their mRNA expression may contribute to the pathogenesis of cleft palate.

Alteration of apoptosis in cleft palate formation and ectomesenchymal stem cells influenced by retinoic acid.

It has been shown that apoptosis is involved in normal embryonic development. The aim of the present study was to elucidate the role and alteration of apoptosis in the pathogenesis of cleft palate induced by retinoic acid (RA) and the ectomesenchymal stem (EMS) cells influenced by RA. RA was administered by gavage to pregnant C57BL/6N strain mice in the experimental group, and the control group received oil alone. Pregnant mice were killed at set periods of time thereafter and histologically analyzed. EMS cells explanted from the palatal shelves of embryonic mice were cultured and characterized by immunohistochemistry, growth curves and population-doubling time. The alterations of apoptosis of EMS cells and developing palatal shelves influenced by RA were evaluated by the terminal deoxynucleotidyl transferase-mediated UTP-biotin nick end-labeling (TUNEL) method. RA-treated mice showed formation of cleft palates resulted from the small size of the palatal shelves and their failure to lift. TUNEL staining showed that the number of apoptotic mesenchymal cells in palatal shelves in the RA-treated mice was increased significantly when compared with the control group. The primary culture of EMS cells proceeded successfully. The population-doubling time of RA-treated cells was much longer compared with non-treated EMS cells. RA also dramatically increased the number of apoptotic cells in EMS cells in vitro. We concluded that EMS cells are the crucial cells in palate development. RA could inhibit the proliferation and induced the apoptosis of EMS cells. The inhibition of growth and excess apoptosis of EMS cells may contribute to the formation of cleft palate and other orofacial congenital malformations.

Lycium barbarum polysaccharides protect rat liver from non-alcoholic steatohepatitis-induced injury.

BACKGROUND: Lycium barbarum polysaccharides (LBPs) are antioxidant and neuroprotective derivative from Wolfberry. However, whether LBP has a protective effect in non-alcoholic steatohepatitis (NASH)-induced hepatic injury is still unknown. OBJECTIVE: We aimed to study the possible hepatoprotective effects and mechanisms of LBP on a diet-induced NASH rat model. METHODS AND DESIGN: In this study, female rats were fed a high-fat diet to induce NASH with or without an oral 1 mg kg(-1) LBP feeding daily for 8 weeks. After 8 weeks, blood serum and liver samples from each rat were subjected to histological analysis, biochemical and molecular measurements. RESULTS: Compared with control rats, NASH rats showed typical NASH features including an increase in liver injury, lipid content, fibrosis, oxidative stress, inflammation and apoptosis. In contrast, NASH+LBP-co-treated rats showed (1) improved histology and free fatty acid levels; (2) re-balance of lipid metabolism; (3) reduction in profibrogenic factors through the TGF-ß/SMAD pathway; (4) improved oxidative stress through cytochrome P450 2E1-dependent pathway; (5) reduction in hepatic pro-inflammatory mediators and chemokines production; and (6) amelioration of hepatic apoptosis through the p53-dependent intrinsic and extrinsic pathways. The preventive effects of LBP were partly modulated through the PI3K/Akt/FoxO1, LKB1/AMPK, JNK/c-Jun and MEK/ERK pathways and the downregulation of transcription factors in the liver, such as nuclear factor-κB and activator protein-1. CONCLUSION: LBP is a novel hepatoprotective agent against NASH caused by abnormal liver metabolic functions.