Gastrointestinal genetic reprogramming of vitamin A metabolic pathways in response of Roux-en-Y gastric bypass.

Roux-en-Y gastric bypass (RYGB) is one of the most performed bariatric surgical techniques. However, RYGB commonly results, as side effects, in nutritional deficiencies. This study aimed to examine changes in the expression of vitamin A pathway encoding genes in the gastrointestinal tract (GI) and to evaluate the potential mechanisms associated with hypovitaminosis A after RYGB. Intestinal biopsies were obtained through double-balloon endoscopy in 20 women with obesity (age 46.9±6.2 years; body mass index [BMI] 46.5±5.3 kg/m2 [mean±SD]) before and three months after RYGB (BMI, 38.2±4.2 kg/m2). Intestinal mucosal gene microarray analyses were performed in samples using a Human GeneChip 1.0 ST array (Affymetrix). Vitamin A intake was assessed from 7-day food records and serum retinol levels were evaluated by electrochemiluminescence immunoassay. Our results showed the following genes with significant downregulation (p≤0.05): LIPF (-0.60), NPC1L1 (-0.71), BCO1 (-0.45), and RBP4 (-0.13) in duodenum; CD36 (-0.33), and ISX (-0.43) in jejunum and BCO1 (-0.29) in ileum. No significant changes in vitamin A intake were found (784±694 retinol equivalents [RE] pre-operative vs. 809±753 RE post-operative [mean±SD]). Although patients were routinely supplemented with 3500 international units IU/day (equivalent to 1050 µg RE/day) of oral retinol palmitate, serum concentrations were lower in the post-operative when compared to pre-operative period (0.35±0.14 µg/L vs. 0.52±0.33 µg/L, respectively - P=0.07), both within the normal range. After RYGB, the simultaneous change in expression of GI genes, may impair carotenoid metabolism in the enterocytes, formation of nascent chylomicrons and transport of retinol, resulting in lower availability of vitamin A.

SAFETY AND EFFICACY OF EUS-GUIDED COIL PLUS CYANOACRYLATE VERSUS CONVENTIONAL CYANOACRYLATE TECHNIQUE IN THE TREATMENT OF GASTRIC VARICES: A RANDOMIZED CONTROLLED TRIAL.

BACKGROUND: One of the most feared complications with the use of cyanoacrylate for treatment of gastric varices is the occurrence of potentially life-threatening systemic embolism. Thus, endoscopists are turning towards new techniques, including endoscopic coiling, as a potentially safer and more effective treatment option. However, no studies have been performed comparing the two techniques. OBJECTIVE: This study aims to compare the safety and efficacy of endoscopic ultrasound guided coil and cyanoacrylate injection versus the conventional technique of injection of cyanoacrylate alone. DESIGN: A pilot randomized controlled trial. METHODS: Patients randomized into group I were treated with coil and cyanoacrylate, and those in group II with cyanoacrylate alone. Flow within the varix was evaluated immediately after the treatment session and one month following initial treatment. If thrombosis was confirmed, additional follow-up was performed 4 and 10 months following initial treatment. All patients underwent a thoracic computerized tomography scan after the procedure. RESULTS: A total of 32 patients, 16 in each group, were followed for an average of 9.9 months (range 1-26 months). Immediately after the procedure, 6 (37.5%) group-I patients and 8 (50%) group-II patients presented total flow reduction in the treated vessel (P=0.476). After 30 days, 11 (73.3%) group-I patients and 12 (75%) group-II patients were found to have varix thrombosis. In both groups, the majority of patients required only one single session for varix obliteration (73.3% in group I versus 80% in group II). Asymptomatic pulmonary embolism occurred in 4 (25%) group-I patients and 8 (50%) group-II patients (P=0.144). No significant difference between the groups was observed. CONCLUSION: There is no statistical difference between endoscopic ultrasound guided coils plus cyanoacrylate versus conventional cyanoacrylate technique in relation to the incidence of embolism. However, a greater tendency towards embolism was observed in the group treated using the conventional technique. Both techniques have similar efficacy in the obliteration of varices. Given the small sample size of our pilot data, our results are insufficient to prove the clinical benefit of the combined technique, and do not yet justify its use, especially in light of higher cost. Further studies with larger sample size are warranted.

Segurança e eficácia do uso de cianoacrilato + coil guiado por ultrassom endoscópico versus técnica convencional de cianoacrilato no tratamento de varizes gástricas: um ensaio clínico randomizado / Safety and efficacy of eus-guided coil plus cyanoacrylate versus conventional cyanoacrylate technique in the treatment of gastric varices: a randomized controlled trial

ABSTRACT BACKGROUND: One of the most feared complications with the use of cyanoacrylate for treatment of gastric varices is the occurrence of potentially life-threatening systemic embolism. Thus, endoscopists are turning towards new techniques, including endoscopic coiling, as a potentially safer and more effective treatment option. However, no studies have been performed comparing the two techniques. OBJECTIVE: This study aims to compare the safety and efficacy of endoscopic ultrasound guided coil and cyanoacrylate injection versus the conventional technique of injection of cyanoacrylate alone. DESIGN: A pilot randomized controlled trial. METHODS: Patients randomized into group I were treated with coil and cyanoacrylate, and those in group II with cyanoacrylate alone. Flow within the varix was evaluated immediately after the treatment session and one month following initial treatment. If thrombosis was confirmed, additional follow-up was performed 4 and 10 months following initial treatment. All patients underwent a thoracic computerized tomography scan after the procedure. RESULTS: A total of 32 patients, 16 in each group, were followed for an average of 9.9 months (range 1-26 months). Immediately after the procedure, 6 (37.5%) group-I patients and 8 (50%) group-II patients presented total flow reduction in the treated vessel (P=0.476). After 30 days, 11 (73.3%) group-I patients and 12 (75%) group-II patients were found to have varix thrombosis. In both groups, the majority of patients required only one single session for varix obliteration (73.3% in group I versus 80% in group II). Asymptomatic pulmonary embolism occurred in 4 (25%) group-I patients and 8 (50%) group-II patients (P=0.144). No significant difference between the groups was observed. CONCLUSION: There is no statistical difference between endoscopic ultrasound guided coils plus cyanoacrylate versus conventional cyanoacrylate technique in relation to the incidence of embolism. However, a greater tendency towards embolism was observed in the group treated using the conventional technique. Both techniques have similar efficacy in the obliteration of varices. Given the small sample size of our pilot data, our results are insufficient to prove the clinical benefit of the combined technique, and do not yet justify its use, especially in light of higher cost. Further studies with larger sample size are warranted.

RESUMO CONTEXTO: Uma das complicações mais temidas com o uso de cianoacrilato para tratamento de varizes gástricas é a ocorrência de embolia sistêmica potencialmente fatal. Assim, os endoscopistas estão se aprimorando com novas técnicas, incluindo o uso de coils endoscópico, como uma opção de tratamento potencialmente mais segura e eficaz. No entanto, nenhum estudo foi realizado comparando as duas técnicas. OBJETIVO: Este estudo tem como objetivo comparar a segurança e eficácia da injeção de coil com cianoacrilato guiados por ultrassom endoscópico versus a técnica convencional de injeção de cianoacrilato. DESIGN: Um ensaio piloto controlado aleatoriamente. MÉTODOS: Os pacientes randomizados para o grupo I foram tratados com coil + cianoacrilato e os do grupo II apenas com cianoacrilato. O fluxo dentro da variz foi avaliado imediatamente após a sessão de tratamento e um mês após o tratamento inicial. Se a trombose foi confirmada, o acompanhamento adicional era realizado em 4 e 10 meses após o tratamento inicial. Todos os pacientes foram submetidos a uma tomografia computadorizada torácica após o procedimento. RESULTADOS: Um total de 32 pacientes, 16 em cada grupo, foram acompanhados por uma média de 9,9 meses (variação de 1-26 meses). Imediatamente após o procedimento, 6 (37,5%) pacientes do grupo I e 8 (50%) pacientes do grupo II apresentaram redução total do fluxo no vaso tratado (P=0,476). Após 30 dias, 11 (73,3%) pacientes do grupo I e 12 (75%) pacientes do grupo II apresentaram trombose da variz. Em ambos os grupos, a maioria dos pacientes necessitou de apenas uma única sessão para obliteração da variz (73,3% no grupo I versus 80% no grupo II). Embolia pulmonar assintomática ocorreu em 4 (25%) pacientes do grupo I e em 8 (50%) pacientes no grupo II (P=0,144). Nenhuma diferença significativa entre os grupos foi observada. CONCLUSÃO Apesar de não haver diferença estatística entre os dois grupos em relação à incidência de embolia neste estudo piloto, observou-se maior tendência de embolia no grupo tratado pela técnica convencional.

Reduced intestinal FADS1 gene expression and plasma omega-3 fatty acids following Roux-en-Y gastric bypass.

BACKGROUND & AIMS: Roux-en-Y gastric bypass (RYGB) limits food ingestion and may alter the intestinal expression of genes involved in the endogenous synthesis of polyunsaturated fatty acids (PUFAs). These changes may decrease the systemic availability of bioactive PUFAs after RYGB. To study the impact of RYGB on the dietary ingestion and plasma concentration of PUFAs and on the intestinal expression of genes involved in their endogenous biosynthesis in severely obese women with type 2 diabetes. METHODS: Before, and 3 and 12 months after RYGB, obese women (n = 20) self-reported a seven-day dietary record, answered a food frequency query and provided plasma samples for alpha-linolenic (ALA), eicosapentaenoic (EPA), docosahexaenoic (DHA) and arachidonic (ARA) acid assessment by gas chromatography. Intestinal biopsies (duodenum, jejunum and ileum) were collected through double-balloon endoscopy before and 3 months after RYGB for gene expression analysis by microarray (Human GeneChip 1.0 ST array) and RT-qPCR validation. RESULTS: Compared to the preoperative period, patients had decreased intakes of PUFAs, fish and soybean oil (p < 0.05) and lower plasma concentrations of ALA and EPA (p < 0.001) 3 and 12 months after RYGB. FADS1 gene expression was lower in duodenum (RT-qPCR fold change = -1.620, p < 0.05) and jejunum (RT-qPCR fold change = -1.549, p < 0.05) 3 months following RYGB, compared to before surgery. CONCLUSION: RYGB decreased PUFA ingestion, plasma ALA and EPA levels, and intestinal expression of FADS1 gene. The latter encodes a key enzyme involved in endogenous biosynthesis of PUFAs. These data suggest that supplementation of omega-3 PUFAs may be required for obese patients undergoing RYGB. Clinical Trial Registry number and website: www.clinicaltrials.gov - NCT01251016; Plataforma Brasil - 19339913.0.0000.0068.