Increased circulating calcitonin in cirrhosis. Relation to severity of disease and calcitonin gene-related peptide

Recent discoveries in microbiota dysbiosis, cholangiocytic factors, and models for studying the pathogenesis of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a cholangiopathy caused by genetic and microenvironmental changes, such as bile homeostasis disorders and microbiota dysbiosis. Therapeutic options are limited, and proven surveillance strategies are currently lacking. Clinically, PSC presents as alternating strictures and dilatations of biliary ducts, resulting in the typical “beaded” appearance seen on cholangiography. The pathogenesis of PSC is still unclear, but cholangiocytes play an essential role in disease development, wherein a reactive phenotype is caused by the secretion of neuroendocrine factors. The liver–gut axis is implicated in the pathogenesis of PSC owing to the dysbiosis of microbiota, but the underlying mechanism is still poorly understood. Alterations in cholangiocyte responses and related signalling pathways during PSC progression were elucidated by recent research, providing novel therapeutic targets. In this review, we summarise the currently known underlying mechanisms of PSC pathogenesis caused by the dysbiosis of microbiota and newly reported information regarding cholangiocytes in PSC. We also summarise recently reported in vitro and in vivo models for studying the pathogenesis of PSC.

Treated with interferon and the gene polymorphism of CGRP and its receptor

OBJECTIVE

This case-control study aims to investigate the relationship of polymorphisms of four gene loci (CGRP rs155209 and rs3781719, RAMP1 rs3754701 and rs7590387) with the prognosis of interferon therapy for chronic hepatitis B (CHB).

MATERIALS AND METHODS

A total of 317 CHB patients receiving interferon alone for the first time were recruited in northern China, and peripheral blood samples were obtained. The single-nucleotide polymorphisms (SNPs) in rs155209, rs3781719, rs3754701, and rs7590387 were genotyped using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Univariate and multivariate logistic regression methods were employed to assess the correlation between CHB prognosis treated with interferon and polymorphisms of these gene loci.

RESULTS

The study clearly demonstrated the relevance of polymorphisms of rs155209, rs3781719, rs3754701, and rs7590387 with DNA response and ALT response after interferon treatment. CHB patients with CGRP rs155209C had a lower risk of developing DNA response (CT vs. TT: OR = 0.159, 95% CI = 0.086-0.294, P_adj < 0.001; CC vs. TT: OR = 0.131, 95% CI = 0.059-0.288, P_adj < 0.001), as well as a lower risk of developing ALT response (CT vs. TT: OR = 0.530, 95% CI = 0.323-0.869, P_adj < 0.05). Moreover, CHB patients with RAMP1 rs3754701T allele were more prone to develop DNA response (AT vs. AA: OR = 2.061, 95% CI = 1.237-3.435, P_adj < 0.05; TT vs. AA: OR = 5.676, 95% CI =1.247-25.837, P_adj < 0.05), and they also more likely to develop ALT response (AT vs. AA: OR = 1.766, 95% CI = 1.098-2.840, P_adj < 0.05). We did not find a significant association between CGRP rs3781719 or RAMP1 rs7590387 and DNA response or ALT response.

CONCLUSION

This study revealed that CGRP rs155209 and RAMP1 rs3754701 polymorphisms, but not CGRP rs3781719 and RAMP1 rs7590387, were correlated with interferon therapy prognosis for CHB in Han Chinese population, and RAMP1 rs3754701T was a protective factor for ALT response and DNA response, but CGRP rs155209C carriers were less prone to DNA and ALT responses.

Knockout of α-calcitonin gene-related peptide attenuates cholestatic liver injury by differentially regulating cellular senescence of hepatic stellate cells and cholangiocytes

α-Calcitonin gene-related peptide (α-CGRP) is a 37-amino acid neuropeptide involved in several pathophysiological processes. α-CGRP is involved in the regulation of cholangiocyte proliferation during cholestasis. In this study, we aimed to evaluate if α-CGRP regulates bile duct ligation (BDL)-induced liver fibrosis by using a α-CGRP knockout (α-CGRP^-/-) mouse model. α-CGRP^-/- and wild-type (WT) mice were subjected to sham surgery or BDL for 7 days. Then, liver fibrosis and cellular senescence as well as the expression of kinase such as p38 and C-Jun N-terminal protein kinase (JNK) in mitogen-activated protein kinases (MAPK) signaling pathway were evaluated in total liver, together with measurement of cellular senescence in cholangiocytes or hepatic stellate cells (HSCs). There was enhanced hepatic expression of Calca (coding α-CGRP) and the CGRP receptor components (CRLR, RAMP-1 and RCP) in BDL and in both WT α-CGRP^-/- and BDL α-CGRP^-/- mice, respectively. Moreover, there was increased CGRP serum levels and hepatic mRNA expression of CALCA and CGRP receptor components in late-stage PSC samples compared to healthy control samples. Depletion of α-CGRP reduced liver injury and fibrosis in BDL mice that was associated with enhanced cellular senescence of hepatic stellate cells and reduced senescence of cholangiocytes as well as decreased activation of p38 and JNK MAPK signaling pathway. Cholangiocyte supernatant from BDL α-CGRP^-/- mice inhibited the activation and increased cellular senescence of cultured human HSCs (HHSCs) compared to HHSCs stimulated with BDL cholangiocyte supernatant. Taken together, endogenous α-CGRP promoted BDL-induced cholestatic liver fibrosis through differential changes in senescence of HSCs and cholangiocytes and activation of p38 and JNK signaling. Modulation of α-CGRP/CGRP receptor signaling may be key for the management of biliary senescence and liver fibrosis in cholangiopathies.

Medullary Thyroid Carcinoma

Medullary thyroid carcinoma (MTC) is subdivided into sporadic (75%) and hereditary (25%) forms. Several germline mutations in the RET proto-oncogene are the source of distinct clinical phenotypes in hereditary MTC including familial MTC (FMTC) and multiple endocrine neoplasia 2A (MEN 2A) and 2B (MEN 2B). The higher the penetrance of the MEN 2 phenotype the earlier the progression of MTC which forms the basis for the currently recommended codon-related concept of prophylactic thyroidectomy. In patients with sporadic MTC, routine calcitonin (CT) measurement in nodular goiter patients has been shown to reduce the frequency of advanced tumor stages. Patients with CT levels over 100 pg/ml after pentagastrin stimulation are recommended for total thyroidectomy. In patients with unexpected sporadic MTC after histological examination, completion thyroidectomy is currently only recommended when CT levels remain elevated. The extent of lymph node dissection in patients with MTC is controversial. However, with respect to lymphonodal micrometastases, systematic compartment-oriented microdissection has been shown to reduce the frequency of lymphonodal recurrence. On the other hand, to avoid unnecessary lymph node dissection, a more individualized concept is required in the future. New chemotherapeutic agents (tyrosine kinase inhibitors), therapeutic nuclids (90Yttrium-labeled octreotide), and chemoembolization of liver metastases are currently the most promising therapeutical concepts in patients with distant metastases.

Diagnóstico, tratamento e seguimento do carcinoma medular de tireoide: recomendações do Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia

Introdução O carcinoma medular de tireoide (CMT) origina-se das células parafoliculares da tireoide e corresponde a 3-4% das neoplasias malignas da glândula. Aproximadamente 25% dos casos de CMT são hereditários e decorrentes de mutações ativadoras no proto-oncogene RET (REarranged during Transfection). O CMT é uma neoplasia de curso indolente, com taxas de sobrevida dependentes do estádio tumoral ao diagnóstico. Este artigo descreve diretrizes baseadas em evidências clínicas para o diagnóstico, tratamento e seguimento do CMT. Objetivo O presente consenso, elaborado por especialistas brasileiros e patrocinado pelo Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia, visa abordar o diagnóstico, tratamento e seguimento dos pacientes com CMT, de acordo com as evidências mais recentes da literatura. Materiais e métodos: Após estruturação das questões clínicas, foi realizada busca das evidências disponíveis na literatura, inicialmente na base de dados do MedLine-PubMed e posteriormente nas bases Embase e SciELO – Lilacs. A força das evidências, avaliada pelo sistema de classificação de Oxford, foi estabelecida a partir do desenho de estudo utilizado, considerando-se a melhor evidência disponível para cada questão. Resultados Foram definidas 11 questões sobre o diagnóstico, 8 sobre o tratamento cirúrgico e 13 questões abordando o seguimento do CMT, totalizando 32 recomendações. Como um todo, o artigo aborda o diagnóstico clínico e molecular, o tratamento cirúrgico inicial, o manejo pós-operatório e as opções terapêuticas para a doença metastática. Conclusões O diagnóstico de CMT deve ser suspeitado na presença de nódulo tireoidiano e história familiar de CMT e/ou associação com feocromocitoma, hiperparatireoidismo e/ou fenótipo sindrômico característico, como ganglioneuromatose e habitus marfanoides. A punção aspirativa por agulha fina do nódulo, a dosagem de calcitonina sérica e o exame anatomopatológico podem contribuir na confirmação do diagnóstico. A cirurgia é o único tratamento que oferece a possibilidade de cura. As opções de tratamento da doença metastática ainda são limitadas e restritas ao controle da doença. Uma avaliação pós-cirúrgica criteriosa para a identificação de doença residual ou recorrente é fundamental para definir o seguimento e a conduta terapêutica subsequente.

Roles of vascular mediators in the pathogenesis of hepatopulmonary syndrome in rats

AIM: To explore the roles of endothelin-1 (ET-1), nitric oxide (NO) and calcitonin gene-related peptide (CGRP) in the pathogenesis of hepatopulmonary syndrome (HPS) in rats.

METHODS: Thirty-two male Wistar rats were randomly and averagely divided into 4 groups: sham operation group, common bile duct ligation (CBDL) 3-wk group, CBDL 4-wk group and CBDL 5-wk group. HPS model was induced by CBDL. Liver function and pathological changes of liver and lung were observed. The concentrations of ET-1 and CGRP in plasma, liver and lung tissues were detected by radioimmunoassay (RIA) and the NO content in serum, liver and lung tissues was measured with nitrate reductase method.

RESULTS: During the pathogenesis of HPS, liver was damaged with inflammation and fibrous hyperplasia. Fibrosis caused the formation of false lobules. Lung structural alterations such as alveolar capillary dilation and angiogenesis, thickened alveolar septa and decreased alveolar capacity were observed. The levels of ET-1, NO and CGRP in plasma, liver and lung tissues were gradually increased from the 3rd to 5th wk after CBDL, which were positively correlated with alanine aminotransferase level (plasma, ET-1: r = 0.9889, P = 0.0111; NO: r = 0.9935, P = 0065; CGRP: r = 0.9714, P = 0.0286; liver tissue: r = 0.9969, P = 0.0035; r = 0.9993, P = 0.0070; r = 0.9507, P = 0.0493; lung tissue: r = 0.9939, P = 0.0061; r = 0.9991, P = 0.0009; r = 0.9557, P = 0.0443).

CONCLUSION: The levels of ET-1, NO and CGRP in plasma, liver and lung are increased markedly during the process of HPS formation, suggesting that vascular mediators such as ET-1, NO and CGRP may play important roles in the pathogenesis of HPS.

Calcitonin levels do not decrease with weaning in chronic alcoholism

OBJECTIVE

Alcohol might increase calcitonin but this assertion is mainly based on the acute effect of the drug in small animals and humans. The aim of this study was to investigate the effect of chronic alcoholic intoxication on plasma calcitonin (CT) levels.

DESIGN

20 smoking male subjects admitted to be weaned from chronic daily alcohol consumption >100 g were included after informed consent. Blood was sampled upon admission (T0) and after 5 (T5) and 21 (T21) days of alcohol weaning to measure mean erythrocyte volume, gamma-glutamyltransferase (GGT), calcium, gastrin, and CT levels. The control group consisted of 30 male subjects with daily alcohol consumption <20 g.

MAIN OUTCOME

The characteristics of the alcohol group were as follows (mean +/- SD): age 41.2 +/- 13 years old; mean erythrocyte volume: 96.0 +/- 4.2 microm(3) (N: 85-95); calcium level: 94.7 +/- 3.7 mg/L (N: 85-105); gastrinemia: 59.3 +/- 14.9 ng/mL (N: <120). At T0 and T21, three alcoholic subjects had CT levels above 10 pg/mL, usually considered as the normal cut-off value. There was no correlation between CT and the different biochemical parameters at T0, T5, and T21. There was no difference between CT levels at the different stages in the alcohol group (T0: 6.4 +/- 3.6 pg/mL; T5: 6.5 +/- 5.3 pg/mL; T21: 8.4 +/- 5.6), although GGT significantly decreased with weaning duration (T0: 248 +/- 354 IU/L; T5: 211 +/- 290 IU/L; T21: 79 +/- 90 IU/L; ANOVA, p <0.05). But a significant difference was found between mean CT levels in the alcohol group and in the control group (3.1 +/- 0.7 pg/mL, p <0.0001).

CONCLUSIONS

This study suggests that mean CT levels of chronically alcoholic smoking male subjects are higher than those of an age- and sex-matched control group. However, most alcoholic patients exhibited CT levels <10 pg/mL. No decrease in CT levels was noted over a short period of alcohol weaning. As CT measurement is currently recommended in thyroid nodule assessment, this finding may be important to know how to decipher borderline values of CT.

Volatile anesthetics inhibit calcitonin gene-related peptide receptor-mediated responses in pithed rats and human neuroblastoma cells

Calcitonin gene-related peptide (CGRP) has a potent vasodilatory effect that is mediated by specific receptors predominantly coupled to the activation of adenylate cyclase. The effects of volatile anesthetics on CGRP-induced vasodilation are unclear. We studied the effects of sevoflurane and isoflurane on CGRP-induced vasodilation in pithed rats and CGRP receptor-mediated responses in SK-N-MC cells, which are used as a model system to study the CGRP receptor and its downstream pathways. Male Wistar rats were pithed by inserting a stainless steel rod into the spinal cord. Mean arterial pressure (MAP) and cardiac output were maintained at approximately 100 mmHg and 50 ml.min(-1), respectively, with continuous infusion of noradrenaline. After 30 min of inhalation of anesthetics, CGRP (0.1, 0.3, 1.0, and 3.0 microg/kg) was administered intravenously. In SK-N-MC cells, CGRP-, forskolin-, or cholera toxin-induced cAMP production was measured with or without anesthetics using radioimmunoassays. CGRP receptor binding density and affinity for the agonist were determined with (2-[125I]iodohystidyl10) CGRP with or without the anesthetics. Sevoflurane (4%) and isoflurane (2%) significantly inhibited the decrease in MAP and systemic vascular resistance. Furthermore, both anesthetics significantly inhibited CGRP- but not forskolin-induced cAMP production. Sevoflurane (4%) and isoflurane (4%) significantly inhibited cholera toxin-induced cAMP production. Both anesthetics did not affect ligand binding. These data suggest that sevoflurane and isoflurane inhibit CGRP-induced vasodilation at the site between the CGRP receptor and adenylate cyclase activation. The inhibitory site of volatile anesthetics on the CGRP receptor-mediated response involves Gs protein.

Effects of transmitters and interleukin-10 on rat hepatic fibrosis induced by CCl4

AIM: To study the effects of transmitters ET, AgII, PGI₂, CGRP and GG on experimental rat hepatic fibrosis and the antifibrogenic effects of IL-10.

METHODS: One hundred SD rats were randomly divided into 3 groups: control group (N): intraperitoneal injection with saline 2 mL·kg^-1 twice a week; the fibrogenesis group (C): intraperitoneal injection with 50% CCl₄ 2 mL·kg^-1 twice a week; IL-10 treated group (E): besides same dosage of CCl₄ given, intraperitoneal injection with IL-10 4 μg·kg^-1 from the third week. In the fifth, the seventh and the ninth week, rats in three groups were selected randomly to collect plasma and liver tissues. The levels of ET, AgII, PGI₂, CGRP and GG were assayed by radioimmunoassay (RIA). The liver fibrosis was observed with silver staining.

RESULTS: The hepatic fibrosis was developed with the increase of the injection frequency of CCl₄. The ET, AgII, PGI₂, CGRP and GG levels in serum of group N were 71.84 ± 60.2 ng·L^-1, 76.21 ± 33.3 ng·L^-1, 313.03 ± 101.71 ng·L^-1, 61.97 ± 21.4 ng·L^-1 and 33.62 ± 14.37 ng·L^-1, respectively; the levels of them in serum of group C were 523.30 ± 129.3 ng·L^-1, 127.24 ± 50.0 ng·L^-1, 648.91 ± 357.29 ng·L^{- 1}, 127.15 ± 62.0 ng·L^-1 and 85.26 ± 51.83 ng·L^{- 1}, respectively; the levels of them in serum of group E were 452.52 ± 99.5 ng·L^-1, 90.60 ± 44.7 ng·L^-1, 475.57 ± 179.70 ng·L^-1, 102.2 ± 29.7 ng·L^-1 and 38.05 ± 19.94 ng·L^-1, respectively. The histological examination showed that the degrees of the rats liver fibrosis in group E were lower than those in group C.

CONCLUSION: The transmitters ET, AgII, PGI₂, CGRP and GG play a significant role in the rat hepatic fibrosis induced by CCl₄. IL-10 has the antagonistic action on these transmitters and can relieve the degree of the liver fibrosis.

Dyssynchronous electrical and mechanical systole in patients with cirrhosis

BACKGROUND/AIMS

Previous investigations have shown a prolonged QT interval in some patients with cirrhosis. The aim of this study was to investigate the relation between electrical and mechanical systole in patients with different degrees of severity of cirrhosis.

METHODS

Forty-eight patients with cirrhosis and portal hypertension, studied during a haemodynamic investigation, were compared to 17 controls.

RESULTS

A prolonged QTc (above 0.440 s(1/2)) was found in 37% of the cirrhotic patients vs. 5.9% in the controls (P=0.03), and there was a correlation to liver dysfunction (P<0.02). A direct relation between QT and time of mechanical systole (tS) was observed in controls (r=0.58, P<0.01), and cirrhotic patients (r=0.44, P<0.002). In patients with a prolonged QTc interval, the difference between electrical and mechanical systole time was substantially longer than in patients with a normal QTc interval (0.078 vs. 0.031 s, P<0.005). The QT values were related to markers of hyperdynamic circulation (r=-0.48 to 0.56, P<0.05-0.001). CONCLUSIONS; Prolonged repolarization, as evidenced by prolonged QTc, is related to both impaired liver function and systemic circulatory dysfunction. In addition these patients have alterations in the cardiac excitation-contraction relation with compromised association between electrical and mechanical function.