ABSTRACT
Dietary factors are believed to potentially influence the risk of pancreatitis. Here, we systematically investigated the causal relationships between dietary habits and pancreatitis by using two-sample Mendelian randomization (MR). Large-scale genome-wide association study (GWAS) summary statistics for dietary habits were obtained from the UK Biobank. GWAS data for acute pancreatitis (AP), chronic pancreatitis (CP), alcohol-induced AP (AAP) and alcohol-induced CP (ACP) were from the FinnGen consortium. We performed univariable and multivariable MR analyses to evaluate the causal association between dietary habits and pancreatitis. Genetically driven alcohol drinking was associated with increased odds of AP, CP, AAP and ACP (all with p < 0.05). Genetic predisposition to higher dried fruit intake was associated with reduced risk of AP (OR = 0.280, p = 1.909 × 10-5) and CP (OR = 0.361, p = 0.009), while genetic predisposition to fresh fruit intake was associated with reduced risk of AP (OR = 0.448, p = 0.034) and ACP (OR = 0.262, p = 0.045). Genetically predicted higher consumption of pork (OR = 5.618, p = 0.022) or processed meat (OR = 2.771, p = 0.007) had a significant causal association with AP, and genetically predicted higher processed meat intake increased the risk of CP (OR = 2.463, p = 0.043). Our MR study showed that fruit intake may be protective against pancreatitis, whereas dietary intake of processed meat has potential adverse impacts. These findings may inform prevention strategies and interventions directed toward dietary habits and pancreatitis.
Subject(s)
Genetic Predisposition to Disease , Pancreatitis, Chronic , Humans , Mendelian Randomization Analysis , Genome-Wide Association Study , Acute Disease , Feeding Behavior , Polymorphism, Single NucleotideABSTRACT
BACKGROUND: Postmenopausal osteoporosis results from estrogen withdrawal and is characterized mainly by bone resorption. Shikonin is a bioactive constitute of Chinese traditional herb which plays a role in antimicrobial and antitumor activities. The study was designed to investigate the role of shikonin on postmenopausal osteoporosis and explore its underlying mechanisms. METHODS: Immunofluorescence staining was performed to evaluate the effects of shikonin on actin ring formation. The expression levels of the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) pathway were determined by Western blot analysis. To determine whether shikonin influences the receptor activator of nuclear factor-κB ligand (RANKL)-induced association between receptor activator of NF-κB (RANK) and tumor necrosis factor receptor associated factor 6 (TRAF6), immunofluorescence staining and immunoprecipitation experiments were performed. During our validation model, histomorphometric examination and micro-computed tomography (CT) were conducted to assess the morphology of osteoporosis. RESULTS: Shikonin prevented bone loss by inhibiting osteoclastogenesis in vitro and improving bone loss in ovariectomized mice in vivo. At the molecular level, Western blot analysis indicated that shikonin inhibited the phosphorylation of inhibitor of NF-κB (IκB), P50, P65, extracellular regulated protein kinases (ERK), c-Jun N-terminal kinase (JNK), and P38. Interaction of TRAF6 and RANK was prevented, and downstream MAPK and NF-κB signaling pathways were downregulated. CONCLUSION: Osteoclastic bone resorption was reduced in the presence of shikonin in vitro and in vivo. Shikonin is a promising candidate for treatment of postmenopausal osteoporosis.
Subject(s)
Bone Resorption/etiology , Bone Resorption/metabolism , Naphthoquinones/pharmacology , Osteogenesis/drug effects , RANK Ligand/metabolism , Signal Transduction/drug effects , TNF Receptor-Associated Factor 6/metabolism , Animals , Biomarkers , Bone Resorption/drug therapy , Bone Resorption/pathology , Cell Differentiation , Cell Survival/drug effects , Disease Models, Animal , Disease Susceptibility , Female , Fluorescent Antibody Technique , Gene Expression Regulation/drug effects , Humans , Immunohistochemistry , Mice , Mitogen-Activated Protein Kinases/metabolism , Models, Biological , NF-kappa B/metabolism , Naphthoquinones/chemistry , Osteoclasts/drug effects , Osteoclasts/metabolism , Osteoporosis, Postmenopausal , Ovariectomy/adverse effects , Protein Binding , Receptor Activator of Nuclear Factor-kappa B/genetics , Receptor Activator of Nuclear Factor-kappa B/metabolism , X-Ray MicrotomographyABSTRACT
Postmenopausal osteoporosis is caused by the deficiency of estrogen, which breaks bone homeostasis and induces levels of pro-inflammatory cytokines. Muscone is a potent anti-inflammatory agent and is used to treat bone fracture in traditional Chinese medicine. However, its anti-osteoclastogenic effects remain unclear. For in vitro study, morphology tests of osteoclastogenesis were firstly performed. And then, factors in RANK-induced NF-κB and MAPK pathways were examined by RT-PCR and Western blot, and the binding of TNF receptor-associated factor (TRAF)6 to RANK was inspected by coimmunoprecipitation and immunofluorescence staining. For in vivo experiments, C57BL/6 ovariectomized (OVX) mice were used for detection, including H&E staining, TRAP staining, and micro CT. As a result, muscone reduced OVX-induced bone loss in mice and osteoclast differentiation in vitro, by inhibiting TRAF6 binding to RANK, and then suppressed NF-κB and MAPK signaling pathways. The expression of the downstream biomarkers was finally inhibited, including NFATc1, CTR, TRAP, cathepsin K, and MMP-9. The inflammatory factors, TNF-a and IL-6, were also reduced by muscone. Taken together, muscone inhibited the binding of TRAF6 to RANK induced by RANKL, thus blocking NF-kB and MAPK pathways, and down-regulating related gene expression. Finally, muscone inhibited osteoclastogenesis and osteoclast function by blocking RANK-TRAF6 binding, as well as downstream signaling pathways in vitro. Muscone also reduced ovariectomy-induced bone loss in vivo.