Lactobacillus rhamnosus GG supernatant upregulates serotonin transporter expression in intestinal epithelial cells and mice intestinal tissues

BACKGROUND

The role that probiotics play in relieving irritable bowel syndrome (IBS) has been demonstrated; however, the mechanism by which IBS is affected remains unclear. In this study, serotonin transporter (SERT) mRNA and serotonin transporter protein (SERT-P) levels in HT-29, Caco-2 cells, and mice intestinal tissues were examined after treatment with Lactobacillus rhamnosus GG supernatant (LGG-s).

METHODS

HT-29 and Caco-2 cells were treated with different concentrations of LGG-s for 12 and 24 h and C57BL/6 mice received supplements of different concentrations for 4 weeks. SERT mRNA and SERT-P levels were detected by real-time PCR and Western blotting.

KEY RESULTS

SERT mRNA and SERT-P levels in HT-29 and Caco-2 cells were higher than those in the control 24 h after treatment. Undiluted LGG-s upregulated SERT mRNA levels by 9.4-fold in the first week, which dropped in the second week. The double-diluted LGG-s upregulated SERT mRNA by 2.07-fold in the first week; levels dropped to 1.75-fold within the second week and under base expression levels by the third week, while they again climbed to 1.56-fold in the fourth week. The triple-diluted LGG-s could not upregulate SERT mRNA expression until the end of the fourth week. The SERT-P levels in the double-diluted LGG-s group were higher than that in the control but fluctuated with time. SERT-P levels in the triple-diluted LGG-s were higher than that in the control in the last 2 weeks and increased with time.

CONCLUSIONS & INFERENCES

LGG-s can upregulate SERT mRNA and SERT-P levels in intestinal epithelial cells and mice intestinal tissues.

Associations of depression with impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in Chinese adults

AIM

To examine the association between depression and impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in middle-aged and elderly Chinese people, and whether depression was associated with different treatment regimens or durations of diabetes.

METHODS

A cross-sectional study was performed among 229,047 adults living in the community aged ≥ 40 years from 25 centres in China. The self-reported depression rating scale Patient Health Questionnaire 9 (PHQ-9) was used to diagnose probable and sub-threshold depression. Glucose metabolism status was determined according to World Health Organization 1999 diagnostic criteria.

RESULTS

The numbers of participants with normal glucose regulation, impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes were 120,458, 59,512, 24,826 and 24,251, respectively. The prevalence of sub-threshold depression in the total sample of participants was 4.8% (4.8%, 4.8%, 4.4% and 5.6% from normal glucose regulation to previously diagnosed diabetes, respectively), and the prevalence of probable depression was 1.1% (1.1%, 1.0%, 0.9% and 1.8% from normal glucose regulation to previously diagnosed diabetes, respectively). Compared with participants with normal glucose regulation, those with previously diagnosed diabetes had increased odds of probable depression [odds ratio (OR) = 1.61, 95% confidence interval (CI) 1.39-1.87] and sub-threshold depression (OR = 1.14, 95% CI 1.06-1.24), after adjustment for multiple confounding factors. Newly diagnosed diabetes or impaired glucose regulation was not associated with depression. Among those with previously diagnosed diabetes, insulin treatment was associated with greater odds of depression compared with no treatment or oral anti-diabetic medicine.

CONCLUSION

Previously diagnosed diabetes, but not newly diagnosed diabetes or impaired glucose regulation, was associated with a higher prevalence of depression. Patients receiving insulin were more likely to have depression than those not receiving treatment or being treated with oral anti-diabetic medicine.

Genome-wide identification and expression analysis of the CPP-like gene family in soybean

Cysteine-rich polycomb-like protein (CPP-like) genes are a group of transcription factors with highly conserved cysteine-rich domains and are widely distributed in animals and plants, but do not present in yeast. Previous studies have shown that members of this family play important roles in the development of reproductive tissue and in the control of cell division in plants. In this study, whole genome identification of soybean CPP transcription factors was performed using bioinformatic methods. The results showed that there were 20 CPP transcription factors in the soybean genome, which encoded for 28 distinct CPP proteins. These transcription factors were distributed on 16 of 20 chromosomes. Phylogenetic relationship analysis showed that expression of CPP gene family members occurred before the differentiation of monocotyledons and dicotyledons. RNA-Seq analysis showed that 5 genes were highly expressed in all tissues, including Glyma10g39080, Glyma01g44670, Glyma101g66920, Glyma02g01540, and Glyma20g28740. One gene (Glyma14g14750) was specifically expressed in young leaves, while 2 genes (Glyma02g01540 and Glyma10g01580) were highly expressed in root nodules. Quantitative reverse transcriptase-polymerase chain reaction analysis revealed that the expression levels of most genes increased in the roots under high temperature stress. Our findings indicate that these genes are not only involved in growth and development, but also in the responses to high temperature stress in soybean roots.

Cohn process influences the functional anticoagulant activity of human protein C

Cohn fraction IV (CFIV) is a byproduct of a plasma fractionation process known as the Cohn process. It is an inexpensive source of protein C, retaining about 90% of protein C (PC) in human plasma. We investigated whether PC is affected during the Cohn process and evaluated correlations among coagulant activity, amidolytic activity and PC antigen during the Cohn process. CFIV was redissolved with citrate-buffered saline for 5 h at 4°C, and then centrifuged at 3500 g for 40 min at 4°C. Functional anticoagulant activity was measured with a one-stage coagulation method based on activated partial thromboplastin time. The functional amidolytic activity of PC was determined using chromogenic substrate assay, and measurement of PC antigen was performed by ELISA. In CFIV, anticoagulant activity declined significantly, with a loss of >80%, while amidolytic activity was not significantly altered, compared to PC antigen. Prior to the Cohn process, high-rank correlations were observed in cryosupernatant, with rs = 0.921 for anticoagulant and amidolytic activities (P = 0.009), 0.896 for anticoagulant activity and antigen (P = 0.014) and 0.832 for amidolytic activity and antigen (P = 0.031). After the Cohn process in CFIV, there was also a high correlation between amidolytic activity and antigen (rs = 0.782, P = 0.038). There were no significant correlations between anticoagulant activity and antigen (rs = 0.223, P = 0.653), or anticoagulant and amidolytic activity (rs = 0.236, P = 0.675). We conclude that the Cohn process significantly influences the anticoagulant activity of PC. Compared to the antigen, PC lost greater than 80% of its anticoagulant activity, but retained its amidolytic activity, during the Cohn process.

Transfer of dietary aflatoxin B1 to milk aflatoxin M1 and effect of inclusion of adsorbent in the diet of dairy cows

The objectives of this study were to investigate the transfer of aflatoxin from feed to milk and to evaluate the effects of Solis Mos (SM; Novus International Inc., St. Charles, MO) on milk aflatoxin M1, plasma biochemical parameters, and ruminal fermentation of dairy cows fed varying doses of aflatoxin B1 (AFB1). Three groups of 8 multiparous Holstein cows in late lactation (days in milk = 271 ± 29; milk yield = 21.6 ± 3.1 kg/d) were assigned to 1 of 3 experiments in a crossover design. Cows in experiment 1 received no aflatoxin, cows in experiment 2 received 20 µg of AFB1/kg of dry matter, and cows in experiment 3 received 40 µg of AFB1/kg of dry matter. Cows in each experiment were assigned to 1 of 2 treatments: control or 0.25% SM. Each experiment consisted of 2 consecutive periods with the first 4 d (d 1 to 4) as adaptation, followed by AFB1 challenge for 7 d (d 5 to 11), and finally clearance for 5 d (d 12 to 16) in each period. Samples of total mixed ration and milk were collected on d 1, 2, and 10 to 14 of each period. Blood samples were collected from the coccygeal vein on d 1, 11, and 14 of each period. Rumen fluid was collected by oral stomach tube 2 h after the morning feeding on d 1 and 11 of each period. Adding SM to basal or AFB1-contaminated diets at 0.25% had no effect on lactation performance, liver function, or immune response. However, addition of SM improved antioxidative status, as indicated by increased plasma concentrations of superoxide dismutase and reduced malondialdehyde regardless of dietary AFB1 level. Addition of SM to the AFB1-free diet eliminated the background AFM1 in milk and increased total ruminal volatile fatty acid (99.6 vs. 94.2 mM) concentrations. Adding SM to the AFB1-contaminated diet in experiment 2 decreased the AFM1 concentration (88.4 vs. 105.3 ng/L) and the transfer of aflatoxin to milk (0.46 vs. 0.56%), and increased total volatile fatty acid concentration (99.8 vs. 93.4 mM). Adding SM to diets with 40 µg/kg of AFB1 did not elicit changes in rumen parameters or AFM1 output. These results indicated that adding SM to diets containing 0 or 20 µg of AFB1/kg decreased milk AFM1 concentration, improved antioxidative status, and altered rumen fermentation, whereas adding SM to a diet containing 40 µg of AFB1/kg did not reduce AFB1 transfer but did increase the antioxidant status of the liver.

Relationship between eNOS gene polymorphism and cerebral infarction of young and middle-aged Chinese Han population

PURPOSE

To discuss the relationship between the acute cerebral infarction of differently aged population and the variable number tandem repeat polymorphism of endothelial nitric oxide synthase (eNOS) gene.

METHODS

The genotypes of 129 acute cerebral infarction patients and 100 healthy control subjects were determined by PCR and polyacrylamide gel electrophoresis (PAGE).

RESULTS

In the patient group, the frequency of allelic gene a was higher than that in the control group (13.56 % vs 3 %, p < 0.01), and the frequencies of the patients followed the descending order from young through middle-aged to elderly (42.31 % vs 17.2 % vs 5.8 %). The frequencies of the young, middle-aged and elderly population in the control group differed significantly (5.55 % vs 2.94 % vs 2.63 %), and those of the young and middle-aged population in the two groups also differed statistically significantly.

CONCLUSION

The ab genotype of eNOS 4th intron is correlated with the acute cerebral infarction of young and middle-aged Chinese Han population that may involve allelic gene a as an independent risk factor (Tab. 3, Fig. 3, Ref. 13).

Phytoestrogen α-zearalanol exerts antiapoptotic effects in differentiated pc12 cells via oestrogen receptor α

Our previous studies have demonstrated that phytoestrogen α-zearalanol (α-ZAL) possesses potential benefits in alleviating cell apoptotic death just like oestrogen. However, the underlying mechanism is not fully understood. This study was designed to test the hypothesis that the neuroprotective effect of α-ZAL is mediated by oestrogen receptor (ER) as α-ZAL owns the benzene ring structure may interact with ER. The present results showed a significant increase in apoptosis in differentiated PC12 cells after a 24-hr exposure to amyloid β-peptide fragment 25-35 (Aβ25-35 ), accompanied by decreasing of bcl-2 expression and increasing bax expression, whereas a pre-treatment with α-ZAL ameliorated these changes induced by Aβ25-35 . In addition, the α-ZAL-mediated cytoprotection was abrogated by ERα antagonist but not by ERβ antagonist. In summary, these data suggest that α-ZAL intervenes against Aβ-induced apoptosis via intersecting bcl-2-bax apoptotic pathway in an ERα-sensitive manner.

Frequency and features of TP53 mutation in 30 Chinese patients with sporadic basal cell carcinoma

BACKGROUND

Basal cell carcinoma (BCC) is a prevalent form of nonmelanoma skin cancer. Although numerous studies in white populations suggest that mutations in the TP53 gene play an important role in the development of BCC, it is not clear whether this is also the case in East Asian populations such as in China.

AIM

To investigate the frequency and the features of TP53 mutation in sporadic BCC in a Chinese population.

METHODS

In total, 30 patients with sporadic BCC, who had previously taken part in a study on PTCH1 mutations, were enrolled. BCC and control cells were obtained by laser-capture microdissection, and DNA was amplified and sequenced for analysis of TP53 mutations.

RESULTS

In the 30 BCC samples, 6 TP53 point mutations were found (frequency of 20%), and 4 of these 6 mutations had ultraviolet (UV)-specific alterations. Combining these results with those of the previous study on PTCH1 mutations, we found that two patients with had three types of genetic alterations (each had two PTCH1 mutations and one TP53 point mutation). A further two patients each had one PTCH1 mutation and one UV signature TP53 mutation. In addition, the total number of UV-specific mutations of PTCH1 and TP53 accounted for 20% of the total patient group.

CONCLUSIONS

The incidence of TP53 mutation in BCC in our Chinese subjects was lower than that reported for white populations. Many of the patients carried mutations of other genes in addition to of TP53. The majority of TP53 mutations were UV-induced specific alterations. However, the results of the two studies on TP53 and PTCH1 indicated that the incidence of UV-specific mutations is much lower in Chinese than in white populations.

Effects of Aspergillus Oryzae Culture and 2-Hydroxy-4-(Methylthio)-Butanoic Acid on In vitro Rumen Fermentation and Microbial Populations between Different Roughage Sources

An in vitro experiment was conducted to evaluate the effects of Aspergillus oryzae culture (AOC) and 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on rumen fermentation and microbial populations between different roughage sources. Two roughage sources (Chinese wild rye [CWR] vs corn silage [CS]) were assigned in a 2×3 factorial arrangement with HMB (0 or 15 mg) and AOC (0, 3, or 6 mg). Gas production (GP), microbial protein (MCP) and total volatile fatty acid (VFA) were increased in response to addition of HMB and AOC (p<0.01) for the two roughages. The HMB and AOC showed inconsistent effects on ammonia-N with different substrates. For CWR, neither HMB nor AOC had significant effect on molar proportion of individual VFA. For CS, acetate was increased (p = 0.02) and butyrate was decreased (p<0.01) by adding HMB and AOC. Increase of propionate was only occurred with AOC (p<0.01). Populations of protozoa (p≤0.03) and fungi (p≤0.02) of CWR were differently influenced by HMB and AOC. Percentages of F. succinogenes, R. albus, and R. flavefaciens (p<0.01) increased when AOC was added to CWR. For CS, HMB decreased the protozoa population (p = 0.01) and increased the populations of F. succinogenes and R. albus (p≤0.03). Populations of fungi, F. succinogenes (p = 0.02) and R. flavefacien (p = 0.03) were increased by adding AOC. The HMB×AOC interactions were noted in MCP, fungi and R. flavefacien for CWR and GP, ammonia-N, MCP, total VFA, propionate, acetate/propionate (A/P) and R. albus for CS. It is inferred that addition of HMB and AOC could influence rumen fermentation of forages by increasing the number of rumen microbes.

Infiltrating Foxp3(+) regulatory T cells from spontaneously tolerant kidney allografts demonstrate donor-specific tolerance

Foxp3(+) regulatory T cells (Tregs) have an essential role in immune and allograft tolerance. However, in both kidney and liver transplantation in humans, FOXP3(+) Tregs have been associated with clinical rejection. Therefore, the role and function of graft infiltrating Tregs have been of great interest. In the studies outlined, we demonstrated that Foxp3(+) Tregs were expanded in tolerant kidney allografts and in draining lymph nodes in the DBA/2 (H-2(d) ) to C57BL/6 (H-2(b) ) mouse spontaneous kidney allograft tolerance model. Kidney allograft tolerance was abrogated after deletion of Foxp3(+) Tregs in DEpletion of REGulatory T cells (DEREG) mice. Kidney allograft infiltrating Foxp3(+) Tregs (K-Tregs) expressed elevated levels of TGF-β, IL-10, interferon gamma (IFN-γ), the transcriptional repressor B lymphocyte-induced maturation protein-1 (Blimp-1) and chemokine receptor 3 (Cxcr3). These K-Tregs had the capacity to transfer dominant tolerance and demonstrate donor alloantigen-specific tolerance to skin allografts. This study demonstrated the crucial role, potency and specificity of graft infiltrating Foxp3(+) Tregs in the maintenance of spontaneously induced kidney allograft tolerance.

Efficacy and safety of entecavir treatment in a heterogeneous CHB population from a ‘real-world’ clinical practice setting in China

Chronic hepatitis B infection is an important cause of liver-related mortality in China. This study assessed the efficacy and safety of entecavir in a heterogeneous patient population from a ‘real-world’ clinical practice setting in China. This prospective, observational cohort provides 48-week data on 2600 patients from 50 sites in China who received entecavir (0.5 or 1.0 mg) and were assessed for virologic, serologic and biochemical responses. Patients were nucleos(t)ide-na€ıve or -experienced and had compensated or decompensated liver function. At Week 48, 1545/2424 (64%) patients with compensated liver disease and 30/44 (68%) patients with decompensated liver disease achieved HBV DNA<50 IU/mL. Greater proportions of nucleos(t)ide-na€ıve than nucleos(t)ide-experienced (69% vs 53%), and adefovir-experienced than lamivudine/ telbivudine-experienced (62% vs 52%) patients achieved this endpoint. Most patients with HBV DNA<50 IU/mL also achieved HBV DNA<12 IU/L (60%, 45% and 61% of nucleos(t)ide-na€ıve, nucleos(t)ide-experienced and decompensated patients, respectively). In patients with compensated liver disease, ALT values normalized in 1532/1792 patients (85%), and HBeAg loss and HBeAg seroconversion were observed in 17% and 15% of treatment-na€ıve and 15% and 11% of treatment-experienced patients. Entecavir was generally well tolerated. Adverse event rates were comparable between treatment-na€ıve and treatment-experienced patients with compensated liver disease, but were higher in decompensated than in compensated patients, consistent with previous reports in these patients with more advanced disease. Four patients discontinued treatment due to adverse events. In a ‘real-world’ setting, entecavir was efficacious and well tolerated throughout 48 weeks in a heterogeneous Chinese CHB population.

Influence of the XbaI polymorphism in the estrogen receptor-α gene on human spermatogenic defects

Polymorphisms of estrogen receptor (ER) genes have been implicated in male infertility, but studies of this association have produced conflicting results. The present study was conducted to examine whether polymorphisms within the ERα and ERβ genes are susceptibility factors for human male idiopathic infertility in Chinese men. We investigated the association between the ERα gene gene and PvuII and XbaI polymorphisms and the ERβ gene and RsaI and AluI polymorphisms and idiopathic male infertility in Han Chinese men. A total of 204 men with oligozoospermia (sperm count <20 x 10(6)/mL) or azoospermia and 252 fertile control men were included in this study. The analysis revealed a strong association between the XbaI genotype distribution and impaired spermatogenesis (P = 0.0018). The frequency of the G allele was significantly lower in patients than in controls (P = 0.003). Furthermore, serum levels of follicle-stimulating hormone and luteinizing hormone in XbaI AA carriers were significantly higher than those in AG or GG carriers. Our findings further support a possible role of ERα in male infertility. Further studies are needed to replicate our findings, as well as to elucidate more fully the biological mechanisms of the modulation of ERα on human spermatogenesis.

Magnetic topology changes induced by lower hybrid waves and their profound effect on edge-localized modes in the EAST tokamak

Strong mitigation of edge-localized modes has been observed on Experimental Advanced Superconducting Tokamak, when lower hybrid waves (LHWs) are applied to H-mode plasmas with ion cyclotron resonant heating. This has been demonstrated to be due to the formation of helical current filaments flowing along field lines in the scrape-off layer induced by LHW. This leads to the splitting of the outer divertor strike points during LHWs similar to previous observations with resonant magnetic perturbations. The change in the magnetic topology has been qualitatively modeled by considering helical current filaments in a field-line-tracing code.

Endometrial cancer metastasize to the skin of lower leg and vagina: case report and literature review

Endometrial cancer is the most frequent malignancy of the female reproductive system, while cutaneous metastasis is extremely rare in endometrial cancer. The authors herein report a case ofendometrial adenocarcinoma (FIGO Stage IIIC2, Grade 2) with metastasis to the skin of right lower leg and vaginal orifice. The patient was treated with local excision and combination chemotherapy, but she did not respond to therapy and died within 11 months. The authors reviewed the clinico-pathologic features, treatment, and prognosis of such case with cutaneous metastasis.

Changes in the oligomerization potential of the division inhibitor UgtP co-ordinate Bacillus subtilis cell size with nutrient availability

How cells co-ordinate size with growth and development is a major, unresolved question in cell biology. In previous work we identified the glucosyltransferase UgtP as a division inhibitor responsible for increasing the size of Bacillus subtilis cells under nutrient-rich conditions. In nutrient-rich medium, UgtP is distributed more or less uniformly throughout the cytoplasm and concentrated at the cell poles and/or the cytokinetic ring. Under these conditions, UgtP interacts directly with FtsZ to inhibit division and increase cell size. Conversely, under nutrient-poor conditions, UgtP is sequestered away from FtsZ in punctate foci, and division proceeds unimpeded resulting in a reduction in average cell size. Here we report that nutrient-dependent changes in UgtP's oligomerization potential serve as a molecular rheostat to precisely co-ordinate B. subtilis cell size with nutrient availability. Our data indicate UgtP interacts with itself and the essential cell division protein FtsZ in a high-affinity manner influenced in part by UDP glucose, an intracellular proxy for nutrient availability. These findings support a model in which UDP-glc-dependent changes in UgtP's oligomerization potential shift the equilibrium between UgtP•UgtP and UgtP•FtsZ, fine-tuning the amount of FtsZ available for assembly into the cytokinetic ring and with it cell size.

Posthatch development of intestinal morphology and digestive enzyme activities in domestic pigeons (Columba livia)

The gastrointestinal tract plays an important role in studies of avian ontogenies because of its key function in nutrient intake. The pattern of intestinal development during postnatal growth in domestic pigeons (Columba livia), as an altricial bird, would be different from the pattern observed in precocial poultry. In this study, the intestinal morphology, mucosal enzyme activities, and pancreatic enzyme activities were determined from hatch to 14 d of age in pigeons. Rapid morphological development was observed immediately after hatching. Villus area and crypt depth increased in parallel in the duodenum and jejunum and more slowly in the ileum. Mucosal enzyme activities per gram of duodenum, jejunum, and ileum varied significantly with segment and age. There were also intestinal segment × age interactions, in which enzyme activity increased most dramatically in the jejunum as compared with the duodenum and ileum for sucrase and maltase activity from day of hatch to 8 d, and for alkaline phosphatase activity through 14 d. However, aminopeptidase-N activity increased most dramatically from day of hatch to 3 d in the ileum as compared with the duodenum and jejunum. Changes in carbohydrate-digesting enzymes activity in duodenum, jejunum, ileum, and pancreas are more pronounced than for protein-digesting enzymes activity from 3 d after hatching. Intestinal total enzyme activities exhibited a steady increase, which was highly correlated with BW. Pancreatic enzymes indicated patterns somewhat similar to those for intestinal enzymes. It was concluded that development of the absorptive area and the capacity for hydrolysis in the duodenum, jejunum, and ileum was rapid immediately after hatching, although rates of development were different in the 3 segments. Young pigeons differ from poultry, in whom intestinal and pancreatic digestive enzyme activities per gram of tissue are generally constant or decline during postnatal development. Also, the data seem consistent with the idea that intestinal hydrolysis may be a determining step in digestion and hence growth.

Effects of methionine hydroxy copper supplementation on lactation performance, nutrient digestibility, and blood biochemical parameters in lactating cows

The objective of this study was to investigate the effects of methionine hydroxy Cu [(HMTBA)(2)-Cu] supplementation on lactation performance, nutrient digestibility, and blood biochemical parameters in lactating cows. Thirty lactating Holstein cows were assigned to 1 of 3 treatments in a randomized block design: (1) Cu sulfate only (S): 12 mg of Cu provided by CuSO(4) per kilogram of concentrate; (2) Cu sulfate and (HMTBA)(2)-Cu (SM): 6 mg of Cu provided by CuSO(4) and 6 mg of Cu provided by (HMTBA)(2)-Cu per kilogram of concentrate; or (3) (HMTBA)(2)-Cu only (M): 12 mg of Cu provided by (HMTBA)(2)-Cu per kilogram of concentrate. The level of dietary Cu was determined according to the NRC (2001) requirement. This experiment lasted for 120 d, with the first 20 d for adaptation and with sample and data collection beginning on d 21. The milk yield and 4% fat-corrected milk yield of cows in the SM treatment tended to increase compared with those in the S and M treatments. Cows fed SM also tended to have higher NDF and ADF apparent digestibility values than did cows fed S or M. Plasma Cu concentration significantly increased for the SM treatment compared with the S and M treatments. Cows fed S had higher plasma K concentration than did cows in the other 2 treatments. In conclusion, replacing one-half of the dietary Cu sulfate with (HMTBA)(2)-Cu increased plasma Cu concentration and tended to improve the neutral and acid detergent fiber apparent digestibility values and the lactation performance of lactating dairy cattle.

Dentin regeneration using deciduous pulp stem/progenitor cells

Reparative dentin formation is essential for maintaining the integrity of dentin structure during disease or trauma. In this study, we investigated stem/progenitor cell-based tissue engineering for dentin regeneration in a large animal model. Porcine deciduous pulp stem/progenitor cells (PDPSCs) were mixed with a beta-tricalcium phosphate (β-TCP) scaffold for dentin regeneration. Different concentrations of PDPSCs were tested to determine the optimal density for dentin regeneration. Aliquots of 5×10(5) PDPSCs in 1 mL resulted in the highest number of cells attached to the scaffold and the greatest alkaline phosphatase activity. We labeled PDPSCs with green fluorescent protein (GFP) and used the optimal cell numbers mixed with β-TCP to repair pulp chamber roof defects in the premolars of swine. Four weeks after transplantation, GFP-positive PDPSCs were observed in PDPSC-embedded scaffold constructs. At 16 weeks after transplantation, the PDPSCs mixed with β-TCP significantly regenerated the dentin-like structures and nearly completely restored the pulp chamber roof defects. This study demonstrated that the PDPSC/scaffold construct was useful in direct pulp-capping and provides pre-clinical evidence for stem/progenitor cell-based dentin regeneration.

Serotonin transporter gene promoter region polymorphisms and serotonin transporter expression in the colonic mucosa of irritable bowel syndrome patients

BACKGROUND

The role of serotonin transporter (SERT) gene polymorphism in irritable bowel syndrome (IBS) has been demonstrated. However, the expression of SERT mRNA and proteins in the colonic mucosa with different 5-HTT gene-linked polymorphic region (5-HTTLPR) genotypes remains unknown. We examined SERT mRNA and protein levels in colon biopsies from patients with different 5-HTTLPR genotypes and evaluated the links between the polymorphism and the expression levels.

METHODS

Two hundred and fifty-four patients with IBS and 120 healthy subjects were studied. DNA samples were extracted from peripheral blood and genotyped by polymerase chain reaction (PCR). SERT mRNA and protein levels were evaluated by quantitative real time PCR and western blotting. The promoter efficiency of the serotonin transporter promoter (SERT-P) was evaluated with luciferase reporter system.

KEY RESULTS

The frequency of the L/L genotype in C-IBS group was significantly higher than that in the control and D-IBS. However, the S/S genotype in D-IBS was significantly higher than that in C-IBS. The transcriptional efficiency of the L/L genotype was significantly higher than that in the L/S and S/S genotype. Patients with the L/L genotype demonstrated increased production of the SERT protein when compared with L/S and S/S patients. The l variant increased SERT promoter activity by 2.43-fold when compared with the s variant.

CONCLUSIONS & INFERENCES

Polymorphism in the promoter region of the SERT gene can influence the expression of SERT mRNA and the levels of the SERT protein in the colonic mucosa, thereby playing a key role in motility-related symptoms of IBS patients.