Comparison of Low Dose Rate and High Dose Rate Brachytherapy Boost Techniques in Prostate Cancer: Evaluation of Toxicity

PURPOSE/OBJECTIVE(S)

The ASCENDE-RT trial has been criticized for higher rates of chronic severe toxicity (18% genitourinary (GU)) than expected with a low dose rate (LDR) boost technique. We compared clinical outcomes of LDR and high dose rate (HDR) boost in the acute and chronic setting from a large single institution experience over a continuous 20-year period, with a focus on GU and gastrointestinal (GI) toxicity during treatment of prostate cancer.

MATERIALS/METHODS

We retrospectively reviewed patients treated with LDR boost (2003 - 2013) and HDR boost (2014 - 2018). Clinical and treatment-related prognostic factors including age, stage, androgen deprivation therapy (ADT), dosimetry details, and toxicity data were recorded. Toxicity was scored according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Multi-variable analysis (MVA) was performed to evaluate variables associated with toxicity.

RESULTS

A total of 184 men were evaluated (87 LDR and 97 HDR) with a median follow-up of 7.1 years and 4.0 years, respectively. Most patients (92% LDR and 57% HDR) received ADT in addition to BT. The median EBRT dose was 46 Gy for LDR and 45 Gy for HDR (range 25 - 50 Gy). Prostate D90% was similar at 104% and 105% in the LDR and HDR groups, respectively. Urethra D10% and Rectum V100% were both higher with LDR compared to HDR with 155% vs 119% and 0.436% vs 0.073%, respectively. Severe (grade 3+) toxicity was rare (Table 1), with 3.4% of LDR patients experiencing grade 3 chronic GU toxicity. With HDR, 3.1% and 1% of patients experienced acute and chronic grade 3 GU toxicity, respectively. Although non-severe GU toxicity (grade 1-2) was similar between groups (95% LDR vs 89% HDR, p = 0.16), LDR patients experienced more grade 2 GU events (80.5% acute; 82.8% chronic) compared to HDR patients (45.4% acute; 57.7% chronic). There were no severe GI toxicities in the acute or chronic period. Non-severe acute GI toxicity was more common with HDR, while non-severe chronic GI toxicity was more common with LDR. On MVA, acute GU toxicity (any grade) was associated with short term ADT (p = 0.01) and Urethra D10% (p < 0.05); Chronic GU toxicity (any grade) was associated with age (p = 0.09) and Prostate V150cc (p = 0.07) but not BT boost technique.

CONCLUSION

This comparative retrospective analysis of BT boost techniques reveals the overall rate of severe GU and GI toxicity to be low with both LDR and HDR. HDR boost appears to have a slightly more favorable ratio of Grade 1 to Grade 2 GU toxicity and improved urethra/rectum dosimetry. Our analysis suggests that the dosimetric advantages of HDR may deliver small reductions in GU toxicity.

p16 INK4A drives nonalcoholic fatty liver disease phenotypes in high fat diet fed mice through biliary E2F1/FOXO1/IGF-1 signaling

BACKGROUND AND AIMS

NAFLD is characterized by steatosis, hepatic inflammation, and fibrosis, which can develop into NASH. Patients with NAFLD/NASH have increased ductular reaction (DR) and biliary senescence. High fat/high cholesterol diet feeding increases biliary senescence, DR, and biliary insulin-like growth factor-1 (IGF-1) expression in mice. p16/IGF-1 converges with fork-head box transcription factor O1 (FOXO1) through E2F1. We evaluated p16 inhibition on NAFLD phenotypes and biliary E2F1/FOXO1/IGF-1 signaling.

APPROACH AND RESULTS

4-week wild-type (C57BL/6J) male mice were fed a control diet (CD) or high fat/high cholesterol diet and received either p16 or control Vivo Morpholino (VM) by tail vein injection 2× during the 16th week of feeding. We confirmed p16 knockdown and examined: (i) NAFLD phenotypes; (ii) DR and biliary senescence; (iii) serum metabolites; and (iv) biliary E2F1/FOXO1/IGF-1 signaling. Human normal, NAFLD, and NASH liver samples and isolated cholangiocytes treated with control or p16 VM were evaluated for p16/E2F1/FOXO1/IGF-1 signaling. p16 VM treatment reduced cholangiocyte and hepatocyte p16. In wild-type high fat/high cholesterol diet mice with control VM, there were increased (i) NAFLD phenotypes; (ii) DR and biliary senescence; (iii) serum metabolites; and (iv) biliary E2F1/FOXO1/IGF-1 signaling; however, p16 VM treatment reduced these parameters. Biliary E2F1/FOX-O1/IGF-1 signaling increased in human NAFLD/NASH but was blocked by p16 VM. In vitro , p16 VM reduced biliary E2f1 and Foxo1 transcription by inhibiting RNA pol II binding and E2F1 binding at the Foxo1 locus, respectively. Inhibition of E2F1 reduced biliary FOXO1 in vitro.

CONCLUSION

Attenuating hepatic p16 expression may be a therapeutic approach for improving NAFLD/NASH phenotypes.

Gallstone and Gallbladder Disease: Biliary Tract and Cholangiopathies

Cholestatic liver diseases are named primarily due to the blockage of bile flow and buildup of bile acids in the liver. Cholestasis can occur in cholangiopathies, fatty liver diseases, and during COVID-19 infection. Most literature evaluates damage occurring to the intrahepatic biliary tree during cholestasis; however, there may be associations between liver damage and gallbladder damage. Gallbladder damage can manifest as acute or chronic inflammation, perforation, polyps, cancer, and most commonly gallstones. Considering the gallbladder is an extension of the intrahepatic biliary network, and both tissues are lined by biliary epithelial cells that share common mechanisms and properties, it is worth further evaluation to understand the association between bile duct and gallbladder damage. In this comprehensive article, we discuss background information of the biliary tree and gallbladder, from function, damage, and therapeutic approaches. We then discuss published findings that identify gallbladder disorders in various liver diseases. Lastly, we provide the clinical aspect of gallbladder disorders in liver diseases and ways to enhance diagnostic and therapeutic approaches for congruent diagnosis. © 2023 American Physiological Society. Compr Physiol 13:4909-4943, 2023.

Endothelin Receptor-A Inhibition Decreases Ductular Reaction, Liver Fibrosis, and Angiogenesis in a Model of Cholangitis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) leads to ductular reaction and fibrosis and is complicated by vascular dysfunction. Cholangiocyte and endothelial cell crosstalk modulates their proliferation in cholestatic models. Endothelin (ET)-1 and ET-2 bind to their receptor, ET-A, and cholangiocytes are a key source of ET-1 after bile duct ligation. We aimed to evaluate the therapeutic potential of ET-A inhibition in PSC and biliary-endothelial crosstalk mediated by this pathway.

METHODS

Wild-type and multidrug resistance 2 knockout (Mdr2-/-) mice at 12 weeks of age were treated with vehicle or Ambrisentan (ET-A antagonist) for 1 week by daily intraperitoneal injections. Human control and PSC samples were used.

RESULTS

Mdr2-/- mice at 4, 8, and 12 weeks displayed angiogenesis that peaked at 12 weeks. Mdr2-/- mice at 12 weeks had enhanced biliary ET-1/ET-2/ET-A expression and secretion, whereas human PSC had enhanced ET-1/ET-A expression and secretion. Ambrisentan reduced biliary damage, immune cell infiltration, and fibrosis in Mdr2-/- mice. Mdr2-/- mice had squamous cholangiocytes with blunted microvilli and dilated arterioles lacking cilia; however, Ambrisentan reversed these alterations. Ambrisentan decreased cholangiocyte expression of pro-angiogenic factors, specifically midkine, through the regulation of cFOS. In vitro, ET-1/ET-A caused cholangiocyte senescence, endothelial cell angiogenesis, and macrophage inflammation. In vitro, human PSC cholangiocyte supernatants increased endothelial cell migration, which was blocked with Ambrisentan treatment.

CONCLUSIONS

ET-A inhibition reduced biliary and liver damage in Mdr2-/- mice. ET-A promotes biliary angiocrine signaling that may, in turn, enhance angiogenesis. Targeting ET-A may prove therapeutic for PSC, specifically patients displaying vascular dysfunction.

Prolonged administration of a secretin receptor antagonist inhibits biliary senescence and liver fibrosis in Mdr2 -/- mice

BACKGROUND AND AIMS

Secretin (SCT) and secretin receptor (SR, only expressed on cholangiocytes within the liver) play key roles in modulating liver phenotypes. Forkhead box A2 (FoxA2) is required for normal bile duct homeostasis by preventing the excess of cholangiocyte proliferation. Short-term administration of the SR antagonist (SCT 5-27) decreased ductular reaction and liver fibrosis in bile duct ligated and Mdr2 -/- [primary sclerosing cholangitis (PSC), model] mice. We aimed to evaluate the effectiveness and risks of long-term SCT 5-27 treatment in Mdr2 -/- mice.

APPROACH AND RESULTS

In vivo studies were performed in male wild-type and Mdr2 -/- mice treated with saline or SCT 5-27 for 3 months and human samples from late-stage PSC patients and healthy controls. Compared with controls, biliary SCT/SR expression and SCT serum levels increased in Mdr2 -/- mice and late-stage PSC patients. There was a significant increase in ductular reaction, biliary senescence, liver inflammation, angiogenesis, fibrosis, biliary expression of TGF-β1/VEGF-A axis, and biliary phosphorylation of protein kinase A and ERK1/2 in Mdr2 -/- mice. The biliary expression of miR-125b and FoxA2 decreased in Mdr2 -/- compared with wild-type mice, which was reversed by long-term SCT 5-27 treatment. In vitro , SCT 5-27 treatment of a human biliary PSC cell line decreased proliferation and senescence and SR/TGF-β1/VEGF-A axis but increased the expression of miR-125b and FoxA2. Downregulation of FoxA2 prevented SCT 5-27-induced reduction in biliary damage, whereas overexpression of FoxA2 reduced proliferation and senescence in the human PSC cell line.

CONCLUSIONS

Modulating the SCT/SR axis may be critical for managing PSC.

Loss of apical sodium bile acid transporter alters bile acid circulation and reduces biliary damage in cholangitis

Primary sclerosing cholangitis (PSC) is characterized by increased ductular reaction (DR), liver fibrosis, hepatic total bile acid (TBA) levels, and mast cell (MC) infiltration. Apical sodium BA transporter (ASBT) expression increases in cholestasis, and ileal inhibition reduces PSC phenotypes. FVB/NJ and multidrug-resistant 2 knockout (Mdr2-/-) mice were treated with control or ASBT Vivo-Morpholino (VM). We measured 1) ASBT expression and MC presence in liver/ileum; 2) liver damage/DR; 3) hepatic fibrosis/inflammation; 4) biliary inflammation/histamine serum content; and 5) gut barrier integrity/hepatic bacterial translocation. TBA/BA composition was measured in cholangiocyte/hepatocyte supernatants, intestine, liver, serum, and feces. Shotgun analysis was performed to ascertain microbiome changes. In vitro, cholangiocytes were treated with BAs ± ASBT VM, and histamine content and farnesoid X receptor (FXR) signaling were determined. Treated cholangiocytes were cocultured with MCs, and FXR signaling, inflammation, and MC activation were measured. Human patients were evaluated for ASBT/MC expression and histamine/TBA content in bile. Control patient- and PSC patient-derived three-dimensional (3-D) organoids were generated; ASBT, chymase, histamine, and fibroblast growth factor-19 (FGF19) were evaluated. ASBT VM in Mdr2-/- mice decreased 1) biliary ASBT expression, 2) PSC phenotypes, 3) hepatic TBA, and 4) gut barrier integrity compared with control. We found alterations between wild-type (WT) and Mdr2-/- mouse microbiome, and ASBT/MC and bile histamine content increased in cholestatic patients. BA-stimulated cholangiocytes increased MC activation/FXR signaling via ASBT, and human PSC-derived 3-D organoids secrete histamine/FGF19. Inhibition of hepatic ASBT ameliorates cholestatic phenotypes by reducing cholehepatic BA signaling, biliary inflammation, and histamine levels. ASBT regulation of hepatic BA signaling offers a therapeutic avenue for PSC.NEW & NOTEWORTHY We evaluated knockdown of the apical sodium bile acid transporter (ASBT) using Vivo-Morpholino in Mdr2KO mice. ASBT inhibition decreases primary sclerosing cholangitis (PSC) pathogenesis by reducing hepatic mast cell infiltration, altering bile acid species/cholehepatic shunt, and regulating gut inflammation/dysbiosis. Since a large cohort of PSC patients present with IBD, this study is clinically important. We validated findings in human PSC and PSC-IBD along with studies in novel human 3-D organoids formed from human PSC livers.

Development and Characterization of Human Primary Cholangiocarcinoma Cell Lines

Cholangiocarcinoma (CCA) is the second most common primary liver tumor and is associated with late diagnosis, limited treatment options, and a 5-year survival rate of around 30%. CCA cell lines were first established in 1971, and since then, only 70 to 80 CCA cell lines have been established. These cell lines have been essential in basic and translational research to understand and identify novel mechanistic pathways, biomarkers, and disease-specific genes. Each CCA cell line has unique characteristics, reflecting a specific genotype, sex-related properties, and patient-related signatures, making them scientifically and commercially valuable. CCA cell lines are crucial in the use of novel technologies, such as three-dimensional organoid models, which help to model the tumor microenvironment and cell-to-cell crosstalk between tumor-neighboring cells. This review highlights crucial information on CCA cell lines, including: i) type of CCA (eg, intra- or extrahepatic), ii) isolation source (eg, primary tumor or xenograft), iii) chemical digestion method (eg, trypsin or collagenase), iv) cell-sorting method (colony isolation or removal of fibroblasts), v) maintenance-medium choice (eg, RPMI or Dulbecco's modified Eagle's medium), vi) cell morphology (eg, spindle or polygonal shape), and vii) doubling time of cells.

Mast cells selectively target large cholangiocytes during biliary injury via H2HR-mediated cAMP/pERK1/2 signaling

Bile ducts are heterogenous in structure and function, and primary sclerosing cholangitis (PSC) damages specific bile ducts leading to ductular reaction (DR), mast cell (MC) infiltration, increased histamine release, inflammation, and fibrosis. Bile duct ligation (BDL) induces large duct damage via cyclic adenosine monophosphate (cAMP)/extracellular signal-related protein kinase (ERK) signaling, and large cholangiocytes express H2 histamine receptor (H2HR). We evaluated how MCs interact with large cholangiocytes during cholestasis. Male wild-type (WT) and MC-deficient (Kit^W-sh ) mice 10-12 weeks of age were subjected to BDL for 7 days. Select Kit^W-sh mice were injected with MCs pretreated with control or H2HR antagonist (ranitidine, 25 μm, 48 h) via tail vein injection. In vitro, MC migration toward small mouse cholangiocytes (SMCCs) and large mouse cholangiocytes (LMCCs) treated with lipopolysaccharide or histamine (±ranitidine) was measured. LMCCs were stimulated with MC supernatants pretreated with control, α-methyl-dl-histidine (to block histamine release), or ranitidine. Liver damage, large duct DR/senescence, inflammation, fibrosis, and cAMP/ERK immunoreactivity increased in BDL WT and Kit^W-sh +MC mice but decreased in BDL Kit^W-sh and Kit^W-sh +MC-H2HR mice. In vitro, MCs migrate toward damaged LMCCs (but not SMCCs) blocked by inhibition of H2HR. Loss of MC histamine or MC-H2HR decreases LMCC proliferation, senescence, H2HR, and cAMP/ERK levels. Human PSC livers have increased MC number found near DR, senescent ducts, and H2HR-positive ducts. Conclusion: Infiltrating MCs preferentially interact with large ducts via H2HR signaling promoting biliary and liver damage. Mediation of MCs may be a therapeutic strategy for PSC.

Biliary Epithelial Senescence in Liver Disease: There Will Be SASP

Cellular senescence is a pathophysiological phenomenon in which proliferative cells enter cell cycle arrest following DNA damage and other stress signals. Natural, permanent DNA damage can occur after repetitive cell division; however, acute stress or other injuries can push cells into premature senescence and eventually a senescence-associated secretory phenotype (SASP). In recent years, there has been increased evidence for the role of premature senescence in disease progression including diabetes, cardiac diseases, and end-stage liver diseases including cholestasis. Liver size and function change with aging, and presumably with increasing cellular senescence, so it is important to understand the mechanisms by which cellular senescence affects the functional nature of the liver in health and disease. As well, cells in a SASP state secrete a multitude of inflammatory and pro-fibrogenic factors that modulate the microenvironment. Cellular SASP and the associated, secreted factors have been implicated in the progression of liver diseases, such as cholestatic injury that target the biliary epithelial cells (i.e., cholangiocytes) lining the bile ducts. Indeed, cholangiocyte senescence/SASP is proposed to be a driver of disease phenotypes in a variety of liver injuries. Within this review, we will discuss the impact of cholangiocyte senescence and SASP in the pathogenesis of cholestatic disorders.

Mast Cells Regulate Ductular Reaction and Intestinal Inflammation in Cholestasis Through Farnesoid X Receptor Signaling

BACKGROUND AND AIMS

Cholestasis is characterized by increased total bile acid (TBA) levels, which are regulated by farnesoid X receptor (FXR)/FGF15. Patients with primary sclerosing cholangitis (PSC) typically present with inflammatory bowel disease (IBD). Mast cells (MCs) (i) express FXR and (ii) infiltrate the liver during cholestasis promoting liver fibrosis. In bile-duct-ligated (BDL) MC-deficient mice (B6.Cg-Kit^W-sh /HNihrJaeBsmJ [Kit^W-sh ]), ductular reaction (DR) and liver fibrosis decrease compared with BDL wild type, and MC injection exacerbates liver damage in normal mice.

APPROACH AND RESULTS

In this study, we demonstrated that MC-FXR regulates biliary FXR/FGF15, DR, and hepatic fibrosis and alters intestinal FXR/FGF15. We found increased MC number and biliary FXR expression in patients with liver injury compared with control. Histamine and FGF19 serum levels and small heterodimer partner expression increase in patients PSC and PSC-IBD compared with healthy controls. MC injection increased liver damage, DR, inflammation, biliary senescence/senescence-associated secretory phenotype (SASP), fibrosis, and histamine in Kit^W-sh mice. Inhibition of MC-FXR before injection reduced these parameters. BDL and Kit^W-sh mice injected with MCs displayed increased TBA content, biliary FXR/FGF15, and intestinal inflammation, which decreased in BDL Kit^W-sh and Kit^W-sh mice injected with MC-FXR. MCs increased ileal FXR/FGF15 expression in Kit^W-sh mice that was reduced following FXR inhibition. BDL and multidrug resistance 2/ATP-binding cassette family 2 member 4 knockout (Mdr2^-/- ) mice, models of PSC, displayed increased intestinal MC infiltration and FXR/FGF15 expression. These were reduced following MC stabilization with cromolyn sodium in Mdr2^-/- mice. In vitro, MC-FXR inhibition decreased biliary proliferation/SASP/FGF and hepatic stellate cell activation.

CONCLUSIONS

Our studies demonstrate that MC-FXR plays a key role in liver damage and DR, including TBA regulation through alteration of intestinal and biliary FXR/FGF15 signaling.

Mast Cells Promote Nonalcoholic Fatty Liver Disease Phenotypes and Microvesicular Steatosis in Mice Fed a Western Diet

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) is simple steatosis but can develop into nonalcoholic steatohepatitis (NASH), characterized by liver inflammation, fibrosis, and microvesicular steatosis. Mast cells (MCs) infiltrate the liver during cholestasis and promote ductular reaction (DR), biliary senescence, and liver fibrosis. We aimed to determine the effects of MC depletion during NAFLD/NASH.

APPROACH AND RESULTS

Wild-type (WT) and Kit^W-sh (MC-deficient) mice were fed a control diet (CD) or a Western diet (WD) for 16 weeks; select WT and Kit^W-sh WD mice received tail vein injections of MCs 2 times per week for 2 weeks prior to sacrifice. Human samples were collected from normal, NAFLD, or NASH mice. Cholangiocytes from WT WD mice and human NASH have increased insulin-like growth factor 1 expression that promotes MC migration/activation. Enhanced MC presence was noted in WT WD mice and human NASH, along with increased DR. WT WD mice had significantly increased steatosis, DR/biliary senescence, inflammation, liver fibrosis, and angiogenesis compared to WT CD mice, which was significantly reduced in Kit^W-sh WD mice. Loss of MCs prominently reduced microvesicular steatosis in zone 1 hepatocytes. MC injection promoted WD-induced biliary and liver damage and specifically up-regulated microvesicular steatosis in zone 1 hepatocytes. Aldehyde dehydrogenase 1 family, member A3 (ALDH1A3) expression is reduced in WT WD mice and human NASH but increased in Kit^W-sh WD mice. MicroRNA 144-3 prime (miR-144-3p) expression was increased in WT WD mice and human NASH but reduced in Kit^W-sh WD mice and was found to target ALDH1A3.

CONCLUSIONS

MCs promote WD-induced biliary and liver damage and may promote microvesicular steatosis development during NAFLD progression to NASH through miR-144-3p/ALDH1A3 signaling. Inhibition of MC activation may be a therapeutic option for NAFLD/NASH treatment.

Mast Cells Induce Ductular Reaction Mimicking Liver Injury in Mice Through Mast Cell-Derived Transforming Growth Factor Beta 1 Signaling

BACKGROUND AND AIMS

Following liver injury, mast cells (MCs) migrate into the liver and are activated in patients with cholestasis. Inhibition of MC mediators decreases ductular reaction (DR) and liver fibrosis. Transforming growth factor beta 1 (TGF-β1) contributes to fibrosis and promotes liver disease. Our aim was to demonstrate that reintroduction of MCs induces cholestatic injury through TGF-β1.

APPROACH AND RESULTS

Wild-type, Kit^W-sh (MC-deficient), and multidrug resistance transporter 2/ABC transporter B family member 2 knockout mice lacking l-histidine decarboxylase were injected with vehicle or PKH26-tagged murine MCs pretreated with 0.01% dimethyl sulfoxide (DMSO) or the TGF-β1 receptor inhibitor (TGF-βRi), LY2109761 (10 μM) 3 days before sacrifice. Hepatic damage was assessed by hematoxylin and eosin (H&E) and serum chemistry. Injected MCs were detected in liver, spleen, and lung by immunofluorescence (IF). DR was measured by cytokeratin 19 (CK-19) immunohistochemistry and F4/80 staining coupled with real-time quantitative PCR (qPCR) for interleukin (IL)-1β, IL-33, and F4/80; biliary senescence was evaluated by IF or qPCR for p16, p18, and p21. Fibrosis was evaluated by sirius red/fast green staining and IF for synaptophysin 9 (SYP-9), desmin, and alpha smooth muscle actin (α-SMA). TGF-β1 secretion/expression was measured by enzyme immunoassay and qPCR. Angiogenesis was detected by IF for von Willebrand factor and vascular endothelial growth factor C qPCR. In vitro, MC-TGF-β1 expression/secretion were measured after TGF-βRi treatment; conditioned medium was collected. Cholangiocytes and hepatic stellate cells (HSCs) were treated with MC-conditioned medium, and biliary proliferation/senescence was measured by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium and qPCR; HSC activation evaluated for α-SMA, SYP-9, and collagen type-1a expression. MC injection recapitulates cholestatic liver injury characterized by increased DR, fibrosis/TGF-β1 secretion, and angiogenesis. Injection of MC-TGF-βRi reversed these parameters. In vitro, MCs induce biliary proliferation/senescence and HSC activation that was reversed with MCs lacking TGF-β1.

CONCLUSIONS

Our study demonstrates that reintroduction of MCs mimics cholestatic liver injury and that MC-derived TGF-β1 may be a target in chronic cholestatic liver disease.

The interplay between mast cells, pineal gland, and circadian rhythm: Links between histamine, melatonin, and inflammatory mediators

Our daily rhythmicity is controlled by a circadian clock with a specific set of genes located in the suprachiasmatic nucleus in the hypothalamus. Mast cells (MCs) are major effector cells that play a protective role against pathogens and inflammation. MC distribution and activation are associated with the circadian rhythm via two major pathways, IgE/FcεRI- and IL-33/ST2-mediated signaling. Furthermore, there is a robust oscillation between clock genes and MC-specific genes. Melatonin is a hormone derived from the amino acid tryptophan and is produced primarily in the pineal gland near the center of the brain, and histamine is a biologically active amine synthesized from the decarboxylation of the amino acid histidine by the L-histidine decarboxylase enzyme. Melatonin and histamine are previously reported to modulate circadian rhythms by pathways incorporating various modulators in which the nuclear factor-binding near the κ light-chain gene in B cells, NF-κB, is the common key factor. NF-κB interacts with the core clock genes and disrupts the production of pro-inflammatory cytokine mediators such as IL-6, IL-13, and TNF-α. Currently, there has been no study evaluating the interdependence between melatonin and histamine with respect to circadian oscillations in MCs. Accumulating evidence suggests that restoring circadian rhythms in MCs by targeting melatonin and histamine via NF-κB may be promising therapeutic strategy for MC-mediated inflammatory diseases. This review summarizes recent findings for circadian-mediated MC functional roles and activation paradigms, as well as the therapeutic potentials of targeting circadian-mediated melatonin and histamine signaling in MC-dependent inflammatory diseases.

Functional Role of the Secretin/Secretin Receptor Signaling During Cholestatic Liver Injury

The gastrointestinal peptide, secretin (Sct) is an important homeostatic regulator of pancreatic and liver secretory function. With regard to the liver, discoveries have been made, in the last decades, indicating a key role for the secretin/secretin receptor axis during normal or cholestatic conditions. Since large cholangiocytes are the only cells to express secretin receptor in the liver, research on secretin also expanded our knowledge on biliary epithelia. In this review we examined in detail the role of the secretin/secretin receptor axis, not only on biliary secretion, but also on cholangiocyte proliferation and senescence, as well as in prompting fibrotic processes involving biliary epithelia. Relevant data on human chronic cholestatic liver diseases, such as primary biliary cholangitis or primary sclerosing cholangitis, and obtained in animal models mimicking the diseases or in correlative studies on human are also reported. The aim of this review is to provide an update on the progress regarding the interactions between secretin and the biliary epithelia in normal and pathological conditions, underlining the aspects that suggests modulation of secretin pathway as a possible therapeutic approach for chronic cholestatic human liver disease.

The Dynamic Interplay Between Mast Cells, Aging/Cellular Senescence, and Liver Disease

Mast cells are key players in acute immune responses that are evidenced by degranulation leading to a heightened allergic response. Activation of mast cells can trigger a number of different pathways contributing to metabolic conditions and disease progression. Aging results in irreversible physiological changes affecting all organs, including the liver. The liver undergoes senescence, changes in protein expression, and cell signaling phenotypes during aging, which regulate disease progression. Cellular senescence contributes to the age-related changes. Unsurprisingly, mast cells also undergo age-related changes in number, localization, and activation throughout their lifetime, which adversely affects the etiology and progression of many physiological conditions including liver diseases. In this review, we discuss the role of mast cells during aging, including features of aging (e.g., senescence) in the context of biliary diseases such as primary biliary cholangitis and primary sclerosing cholangitis and nonalcoholic fatty liver disease.

Downregulation of p16 Decreases Biliary Damage and Liver Fibrosis in the Mdr2/ Mouse Model of Primary Sclerosing Cholangitis

Biliary senescence and hepatic fibrosis are hallmarks of cholangiopathies including primary sclerosing cholangitis (PSC). Senescent cholangiocytes display senescence-associated secretory phenotypes [SASPs, e.g., transforming growth factor-1 (TGF-1)] that further increase biliary senescence (by an autocrine loop) and trigger liver fibrosis by paracrine mechanisms. The aim of this study was to determine the effect of p16 inhibition and role of the TGF-1/microRNA (miR)-34a/sirtuin 1 (SIRT1) axis in biliary damage and liver fibrosis in the Mdr2/ mouse model of PSC. We treated (i) in vivo male wild-type (WT) and Mdr2/ mice with p16 Vivo-Morpholino or controls before measuring biliary mass [intrahepatic bile duct mass (IBDM)] and senescence, biliary SASP levels, and liver fibrosis, and (ii) in vitro intrahepatic murine cholangiocyte lines (IMCLs) with small interfering RNA against p16 before measuring the mRNA expression of proliferation, senescence, and fibrosis markers. p16 and miR-34a increased but SIRT1 decreased in Mdr2/ mice and PSC human liver samples compared to controls. p16 immunoreactivity and biliary senescence and SASP levels increased in Mdr2/ mice but decreased in Mdr2/ mice treated with p16 Vivo-Morpholino. The increase in IBDM and hepatic fibrosis (observed in Mdr2/ mice) returned to normal values in Mdr2/ mice treated with p16 Vivo-Morpholino. TGF-1 immunoreactivity and biliary SASPs levels were higher in Mdr2/ compared to those of WT mice but returned to normal values in Mdr2/ mice treated with p16 Vivo-Morpholino. The expression of fibrosis/senescence markers decreased in cholangiocytes from Mdr2/ mice treated with p16 Vivo-Morpholino (compared to Mdr2/ mice) and in IMCLs (after p16 silencing) compared to controls. Modulation of the TGF-1/miR-34a/SIRT1 axis may be important in the management of PSC phenotypes.

Amelioration of Large Bile Duct Damage by Histamine-2 Receptor Vivo-Morpholino Treatment

Histamine binds to one of the four G-protein-coupled receptors expressed by large cholangiocytes and increases large cholangiocyte proliferation via histamine-2 receptor (H2HR), which is increased in patients with primary sclerosing cholangitis (PSC). Ranitidine decreases liver damage in Mdr2^-/- (ATP binding cassette subfamily B member 4 null) mice. We targeted hepatic H2HR in Mdr2^-/- mice using vivo-morpholino. Wild-type and Mdr2^-/- mice were treated with mismatch or H2HR vivo-morpholino by tail vein injection for 1 week. Liver damage, mast cell (MC) activation, biliary H2HR, and histamine serum levels were studied. MC markers were determined by quantitative real-time PCR for chymase and c-kit. Intrahepatic biliary mass was detected by cytokeratin-19 and F4/80 to evaluate inflammation. Biliary senescence was determined by immunofluorescence and senescence-associated β-galactosidase staining. Hepatic fibrosis was evaluated by staining for desmin, Sirius Red/Fast Green, and vimentin. Immunofluorescence for transforming growth factor-β₁, vascular endothelial growth factor-A/C, and cAMP/ERK expression was performed. Transforming growth factor-β₁ and vascular endothelial growth factor-A secretion was measured in serum and/or cholangiocyte supernatant. Treatment with H2HR vivo-morpholino in Mdr2^-/--mice decreased hepatic damage; H2HR protein expression and MC presence or activation; large intrahepatic bile duct mass, inflammation and senescence; and fibrosis, angiogenesis, and cAMP/phospho-ERK expression. Inhibition of H2HR signaling ameliorates large ductal PSC-induced damage. The H2HR axis may be targeted in treating PSC.

Bile Acid Receptor Therapeutics Effects on Chronic Liver Diseases

In the past ten years, our understanding of the importance of bile acids has expanded from fat absorption and glucose/lipid/energy homeostasis into potential therapeutic targets for amelioration of chronic cholestatic liver diseases. The discovery of important bile acid signaling mechanisms, as well as their role in metabolism, has increased the interest in bile acid/bile acid receptor research development. Bile acid levels and speciation are dysregulated during liver injury/damage resulting in cytotoxicity, inflammation, and fibrosis. An increasing focus to target bile acid receptors, responsible for bile acid synthesis and circulation, such as Farnesoid X receptor and apical sodium-dependent bile acid transporter to reduce bile acid synthesis have resulted in clinical trials for treatment of previously untreatable chronic liver diseases such as non-alcoholic steatohepatitis and primary sclerosing cholangitis. This review focuses on current bile acid receptor mediators and their effects on parenchymal and non-parenchymal cells. Attention will also be brought to the gut/liver axis during chronic liver damage and its treatment with bile acid receptor modulators. Overall, these studies lend evidence to the importance of bile acids and their receptors on liver disease establishment and progression.

Differential Effect of Oxicam Non-Steroidal Anti-Inflammatory Drugs on Membranes and Their Consequence on Membrane Fusion

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly used analgesics and antipyretics, which form an interesting drug group because of their new and alternate functions. The ability of the NSAIDs belonging to the oxicam chemical group to induce membrane fusion at low physiologically relevant concentrations is a new function that has drawn considerable attention. Membrane fusion is dependent on the interplay of physicochemical properties of both drugs and membranes. Here, we have elucidated the effects of different oxicam drugs, Meloxicam, Piroxicam, Tenoxicam, Lornoxicam, and Isoxicam, on an identical membrane-mimetic system. This highlights only the differential effects of the drugs on drug-membrane interactions, which in turn modulate their role as membrane fusogens. The partitioning behavior and the location of the drugs in dimyristoylphosphatidylcholine vesicles have been studied using second-derivative absorption spectroscopy, fluorescence quenching, steady-state fluorescence anisotropy, and time-resolved fluorescence lifetime measurements. Fusion kinetics has been monitored by fluorescence assays and dynamic light scattering was used to provide a snapshot of the vesicle diameter distribution at different time points. The differential perturbing effect of the drugs on the membrane is dependent both on their partitioning and location. Although partitioning governs the extent of fusion, the location modulates the rates of each step.

Relation of iron stores to oxidative stress in type 2 diabetes

BACKGROUND

Recent studies revealed elevated serum ferritin levels predict new-onset type 2 diabetes. Further studies proved ferritin to be an important and independent predictor of the development of diabetes. The link between hyperglycemia, enhanced free radical activity (oxidative stress) and serum iron and its stores (serum ferritin levels) levels is not clear.

OBJECTIVES

The present study is an attempt to understand the relationship between serum ferritin levels and oxidative stress (measured by malondialdehyde).

MATERIALS AND METHODS

The study comprised of 30 apparently healthy controls and 30 type 2 diabetic patients who attended the outpatient and inpatient departments of Medical College, Kolkata. Levels of fasting blood glucose, postprandial blood glucose, serum iron, serum ferritin, glycosylated hemoglobin (HbA1c) and malondialdehyde (MDA), serum urea and creatinine were estimated. The statistical software SPSS 11.0 and Systat 8.0 were used for the analysis of the data and Microsoft Word and Excel have been used to generate tables and graphs.

RESULTS

Serum iron (82.16 ± 13.24 μg/dl), serum ferritin (224.53 ± 96.06 μg/L), HbA1c (8.62 ± 1.79%), MDA (2.66 ± 0.76 nmol/ml) levels were significantly higher in type 2 diabetics compared with apparently healthy controls. Elevations in serum iron, ferritin and HbA1c are accompanied by a parallel increase in blood glucose. Based on groups of glycemic control, i.e. HbA1c levels >8%, serum ferritin levels were highest, 258.63 ± 22.67 μg/dl. There is an inverse correlation of serum ferritin levels to MDA levels in the diabetic cases of longer duration of more than 10 years.

CONCLUSION

Serum ferritin level in the present study is found to be higher in the newly diagnosed cases and lower in those patients suffering from diabetes for more than 10 years. This study probably suggests that serum ferritin can represent either as a pro-oxidant or as an antioxidant in a time-dependent manner.

Prevalence of Tinea capitis in school going children in Kolkata, West Bengal

Background:

In recent years the incidence of Tinea capitis, infection of scalp by dermatophytes, has increased in United Kingdom and North America. The trend may be similar in India. The objective of this study is to find the prevalence of Tinea capitis in school going urban children in Kolkata, West Bengal state.

Materials and Methods:

The present study is a cross-sectional study conducted in a government higher primary school in Kolkata.

Results:

Totally 505 students were screened and 52 were diagnosed to have Tinea capitis by clinical examination, giving a prevalence rate of 10% among school children. Prevalence rates among the age groups of 6–8, 9–11 and 12–14 years were almost the same, ranging from 9 to 11%. The prevalence rate was significantly high among the boys (14%). There was no significant difference in prevalence of infection among coconut oil users and castor oil users. Measures of general hygiene were similar among those who were infected with Tinea capitis and those who were not. The commonest clinical type of infection found was dull grey patches. Itching with hair loss was the major symptom and most of the infected children had cervical lymphadenopathy. The potassium hydroxide studies revealed endothrix spores in majority of samples.

Conclusion:

Tinea capitis in prevalent in school going urban children in Kolkata, West Bengal state and necessary measures must be undertaken to curtail this incidence.

Comparison of bioactive glass coated and hydroxyapatite coated titanium dental implants in the human jaw bone

BACKGROUND

Current trends in clinical dental implant therapy include modification of titanium surfaces for the purpose of improving osseointegration by different additive (bioactive coatings) and subtractive processes (acid etching, grit-blasting). The aim of this study was to evaluate and compare the behaviour of hydroxyapatite and the newly developed bioactive glass coated implants (62 implants) in osseous tissue following implantation in 31 patients.

METHODS

Bioactive glass and hydroxyapatite was suitably coated on titanium alloy. Hydroxyapatite coating was applied on the implant surface by air microplasma spray technique and bioactive glass coating was applied by vitreous enamelling technique. The outcome was assessed up to 12 months after prosthetic loading using different clinical and radiological parameters.

RESULTS

Hydroxyapatite and bioactive glass coating materials were non-toxic and biocompatible. Overall results showed that bioactive glass coated implants were as equally successful as hydroxyapatite in achieving osseointegration and supporting final restorations.

CONCLUSIONS

The newly developed bioactive glass is a good alternative coating material for dental implants.

Thermal Stability of Structurally Controlled Lamellae and Hexagonal Mesoporous Silicate Thin Films

Thin films of mesoporous materials have been synthesized recently as lamellar, one dimensional hexagonal and cubic structures at substrate surfaces as well as at air/liquid interfaces. The present work investigates thermally induced structural changes of lamellar and one-dimensional hexagonal(1-dH) mesostructured silicate thin films, which is less known at the moment. The 1-dH films proved to be much more thermally stable than the lamellar ones; Open-pore one dimensionalhexagonalmesoporous thin films are obtained by the calcination of the films, where as the lamellarphase has collapsed after the surfactants removal.

Application of chemically modified rice husk for the removal of heavy metals from aqueous solution

The removal efficiency of lead, cadmium and zinc from aqueous solution on adsorption by using rice husk, a non-conventional material in its natural and chemically modified form has been presented in this paper. It has been observed that rate of adsorption is dependent on the nature of the adsorbent, adsorbent dose, particle size of the adsorbent, concentration, pH, contact time, temperature, etc. Under identical experimental condition chemically modified rice husk was found to possess greater adsorption capacity for all metals than untreated rice husk and chemically modified rice husk ash. Chemically modified rice husk could remove 99.8% Pb, 95% Cd and 97% Zn from aqueous solution at room temperature.

Leaching of lead and cadmium from glass dinnerware

Heavy metals like lead and cadmium were found to leach out from food contact surface of opal glass dinnerware when treated with five food acids as a leaching solution. The leachates used were: acetic acid, tartaric acid, citric acid, lactic acid and ascorbic acid at three different concentrations 2%, 4%, and 8% (v/v). At room temperature, duration of leaching varied from 1h to 24h in each case. The amount of metals leached in individual acid was found to be maximum at the 4% acid concentration. Release of Pb and Cd was faster in first 2h leaching period. Maximum amount of Pb and Cd were leached in 4% acetic acid at room temperature.