RESUMO
OBJECTIVES: Vitamin B2 (riboflavin) has a prime role in metabolic reactions imperative to cell cycle and proliferation. We investigated the associations between serum concentrations of riboflavin flavin mononucleotide with the risk of pancreatic cancer in a nested case-control study involving 58 cases and 104 matched controls. METHODS: The Singapore Chinese Health Study, an ongoing prospective cohort study of 63,257 Chinese Singaporeans. Conditional logistic regression method was used to evaluate these associations with adjustment for potential confounders including the level of education, body mass index, smoking status, alcohol consumption, history of diabetes, serum cotinine and pyridoxal 5'-phosphate, estimated glomerular filtration rate, and total methyl donors (ie, the sum of serum choline, betaine, and methionine). RESULTS: The risk of pancreatic cancer increased with increasing level of serum riboflavin in a dose-dependent manner, especially in men (Ptrend = 0.003). The odds ratio (95% confidence intervals) of pancreatic cancer for the second and third tertiles of serum riboflavin, compared with the lowest tertile, were 9.92 (1.65-59.77) and 25.59 (3.09-212.00), respectively. This positive association was stronger in individuals with a longer follow-up period (≥7 years). CONCLUSIONS: The findings suggest a potential role of riboflavin in the development of pancreatic cancer, especially in men.
Assuntos
Mononucleotídeo de Flavina , Neoplasias Pancreáticas , Riboflavina , Humanos , Masculino , Estudos de Casos e Controles , Mononucleotídeo de Flavina/sangue , Neoplasias Pancreáticas/metabolismo , Estudos Prospectivos , Riboflavina/sangue , Fatores de Risco , Vitamina B 6RESUMO
OBJECTIVES: Assess if kynurenines metabolites are biomarkers of damage at labial salivary gland biopsy (LSGB). METHODS: This is a cross-sectional study including 99 patients with primary Sjögren's syndrome (AECG 2002 or ACR/EULAR 2017). Kynurenines were measured in plasma using liquid chromatography-tandem mass spectrometry. RESULTS: 95.9% were females, 51±12 years. Most had focal lymphocytic sialadenitis with focus score ≥1 (73.7%, n=73/99). The majority had mild to severe acinar atrophy (70.4%, n=57/81) and adipose infiltration (51.2%, n=39/80). Individuals with adipose infiltration were older (53.49±12.33 vs. 47.51±11.29 years, p=0.016), showed higher frequency of glandular dysfunction and higher kynurenines levels. Schirmer's test ≤ 5 mm/5min was found in 69.2% of individuals with adipose infiltration compared to 41% without (p=0.012) and unstimulated whole salivary flow (UWSF) was found in 87.2% compared to 70% without adipose infiltration (p=0.063). Additionally, individuals with adipose infiltration showed higher kynurenines metabolites compared with those without: quinolinic acid (503.35±193.30 vs. 427.35±285.76 nmol/L, p=0.029), kynurenine (1.99±0.6, 54 vs. 1.61±0.46 µmol/L, p=0.006), kynurenine/tryptophan ratio (KTR) (0.030±0.09 vs. 0.025±0.01, p=0.031) and anthranilic acid (03±4.96 vs. 16.46±5.24 nmol/L, p=0.022). CONCLUSIONS: Kynurenines are biomarkers of greater adipose infiltration in LSGB and glandular dysfunction suggesting that activation of interferon-γ pathway is involved in the salivary and lacrimal glands damage.