Bidirectional effects of the tryptophan metabolite indole-3-acetaldehyde on colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) has a high incidence and mortality. Recent studies have shown that indole derivatives involved in gut microbiota metabolism can impact the tumorigenesis, progression, and metastasis of CRC. AIM: To investigate the effect of indole-3-acetaldehyde (IAAD) on CRC. METHODS: The effect of IAAD was evaluated in a syngeneic mouse model of CRC and CRC cell lines (HCT116 and DLD-1). Cell proliferation was assessed by Ki-67 fluorescence staining and cytotoxicity tests. Cell apoptosis was analysed by flow cytometry after staining with Annexin V-fluorescein isothiocyanate and propidium iodide. Invasiveness was investigated using the transwell assay. Western blotting and real-time fluorescence quantitative polymerase chain reaction were performed to evaluate the expression of epithelial-mesenchymal transition related genes and aryl hydrocarbon receptor (AhR) downstream genes. The PharmMapper, SEA, and SWISS databases were used to screen for potential target proteins of IAAD, and the core proteins were identified through the String database. RESULTS: IAAD reduced tumorigenesis in a syngeneic mouse model. In CRC cell lines HCT116 and DLD1, IAAD exhibited cytotoxicity starting at 24 h of treatment, while it reduced Ki67 expression in the nucleus. The results of flow cytometry showed that IAAD induced apoptosis in HCT116 cells but had no effect on DLD1 cells, which may be related to the activation of AhR. IAAD can also increase the invasiveness and epithelial-mesenchymal transition of HCT116 and DLD1 cells. At low concentrations (< 12.5 µmol/L), IAAD only exhibited cytotoxic effects without promoting cell invasion. In addition, predictions based on online databases, protein-protein interaction analysis, and molecular docking showed that IAAD can bind to matrix metalloproteinase-9 (MMP9), angiotensin converting enzyme (ACE), poly(ADP-ribose) polymerase-1 (PARP1), matrix metalloproteinase-2 (MMP2), and myeloperoxidase (MPO). CONCLUSION: Indole-3-aldehyde can induce cell apoptosis and inhibit cell proliferation to prevent the occurrence of CRC; however, at high concentrations (≥ 25 µmol/L), it can also promote epithelial-mesenchymal transition and invasion in CRC cells. IAAD activates AhR and directly binds MMP9, ACE, PARP1, MMP2, and MPO, which partly reveals why it has a bidirectional effect.

Function of macrophage-derived exosomes in chronic liver disease: From pathogenesis to treatment.

Chronic liver disease (CLD) imposes a heavy burden on millions of people worldwide. Despite substantial research on the pathogenesis of CLD disorders, no optimal treatment is currently available for some diseases, such as liver cancer. Exosomes, which are extracellular vesicles, are composed of various cellular components. Exosomes have unique functions in maintaining cellular homeostasis and regulating cell communication, which are associated with the occurrence of disease. Furthermore, they have application potential in diagnosis and treatment by carrying diverse curative payloads. Hepatic macrophages, which are key innate immune cells, show extraordinary heterogeneity and polarization. Hence, macrophage-derived exosomes may play a pivotal role in the initiation and progression of various liver diseases. This review focuses on the effects of macrophage-derived exosomes on liver disease etiology and their therapeutic potential, which will provide new insights into alleviating the global pressure of CLD.

Associations between Dietary Antioxidant Vitamin Intake and the Changes in Bone Mass in Chinese Adolescents: A 2.5-Year Longitudinal Study.

(1) Background: Optimal bone mass accumulation during adolescence is crucial for maximising peak bone mass during adulthood. Dietary antioxidant vitamins may contribute to bone mass accumulation. This 2.5-year-long longitudinal study aimed to evaluate the relationships between dietary vitamin A, C, and E intakes and the annual changes in bone parameters among Chinese adolescents. (2) Method: Subjects aged 10-18 years (n = 1418) were recruited from a secondary school in Jiangmen, China. Dietary vitamin A, C, and E intakes were assessed using 24 h dietary records over 3 consecutive days. The Sahara Clinical Bone Sonometer was used to measure the broadband ultrasound attenuation (BUA) and the speed of sound (SOS). Their annual changes were then calculated (i.e., BUA%/year, SOS%/year). The associations were detected after adjusting for the baseline bone phenotype; age; sex; weight; height; pubertal stage; physical activity; and dietary intakes of vitamin D, calcium and energy. (3) Results: A curvilinear relationship was found between the dietary intake of vitamin C and BUA%/year (p = 0.026); further analyses in the subgroups revealed that this relationship was observed in male adolescents (p = 0.012). A positive association was observed only in boys with a dietary vitamin C intake of ≥159.01 mg/day (ß = 0.395, p = 0.036). Moreover, a linear positive association was shown between the dietary intake of vitamin E and BUA%/year in female adolescents (ß = 0.082, p = 0.033). (4) Conclusion: Our findings indicated that dietary vitamin C intake has a threshold effect on bone mass gain in male adolescents and that dietary vitamin E intake could be a positive predictor of bone mass gain in female adolescents.

Analysis of the Association between Fat Mass Distribution and Bone Mass in Chinese Male Adolescents at Different Stages of Puberty.

BACKGROUND: Bone mineral acquisition during adolescence is crucial for maximizing peak bone mass. Fat mass (FM) and bone mass are closely related. This study investigated the association of FM distribution with bone mass in Chinese male adolescents. METHOD: A total of 693 male adolescents aged 10-18 years were recruited from a secondary school in Jiangmen, China. Their bone mass and body composition were measured by quantitative ultrasound and bioelectrical impedance analysis, respectively. The associations of the measures of fat distribution with bone parameters, i.e., broadband ultrasound attenuation, speed of sound (SOS), and stiffness index (SI), were analyzed using multiple linear regression. Age, height, body mass index, stage of puberty, physical activity, sedentary behavior, dietary energy intake, and dietary calcium and vitamin D intake were adjusted in the model. Further subgroup analyses of prepubertal and pubertal participants were conducted. RESULTS: The measures of fat distribution showed negative associations with SOS and SI in total subjects (p < 0.010). In prepubertal boys, the measures of fat distribution were only associated with SOS (ß = -0.377 to -0.393, p < 0.050). In pubertal boys, the measures of fat distribution had associations with all bone parameters (ß = -0.205 to -0.584, p < 0.050). The strongest association was between trunk FM and SOS (ß = -0.584, p < 0.001). CONCLUSION: This study supported that the measures of fat distribution were negatively associated with bone parameters in Chinese male adolescents. Trunk FM had the strongest association with bone parameter. These associations appear to be stronger in pubertal boys than in prepubertal boys.

Association between Body Composition and Bone Mineral Density in Children and Adolescents: A Systematic Review and Meta-Analysis.

BACKGROUND: Bone mass acquisition during growth is a major determinant of the risk of developing osteoporosis later in life. Body composition is an anthropometric determinant of bone mineral density (BMD) and significantly influences its development during childhood and adolescence. OBJECTIVE: This study aimed to systematically examine the association between body composition and bone mineral density in children and adolescents. METHODS: Observational studies addressing this association were identified from PubMed (MEDLINE), Embase, Scopus and the Cochrane Library (up to January 2021). The study populations consisted of healthy children and adolescents. The DerSimonian and Laird method was used to compute pooled estimates of effect size and the respective 95% confidence intervals for upper limbs, femoral neck (FN), lumbar spine (LS) and total body, respectively. Subgroup analyses were further performed based on age, sex and ethnicity. RESULTS: Thirty-one published studies were eligible for inclusion in this systematic review and meta-analysis, including three longitudinal studies. The combined population from all the studies amounted to 21,393 (11,205 males and 10,188 females). The pooled estimates of the correlation coefficients for lean mass (LM) and BMD ranged from 0.53 to 0.74 (p < 0.050), and the pooled regression coefficients ranged from 0.23 to 0.79 for FN, LS and total body (p < 0.050). For fat mass (FM), the pooled correlation coefficients ranged from 0.10 to 0.50 (p < 0.050) and the pooled regression coefficient was only significant for FN BMD with a weak strength (pooled ß = 0.07, p < 0.050). The pooled regression coefficients for body fat percentage (BF%) were between -0.54 and -0.04 (p < 0.050). The subgroup analysis revealed a stronger association in Asians than in Caucasians for LM and in males compared to females for BF% (p < 0.050). CONCLUSIONS: This systematic review and meta-analysis supports a positive association between LM and BMD. BF% appears to have a deleterious effect on bone acquisition in children and adolescents.

Effect of hormone therapy on muscle strength in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: This study aimed to evaluate the overall effects of hormone therapy (HT) on muscle strength in postmenopausal women through a systematic review and meta-analysis. METHODS: PubMed, Web of Science, Embase, and the Cochrane Central Register of Controlled Trials were systematically searched from the inception dates to August 2019. Randomized controlled trials (RCTs) that compared the effects of HT with either no therapy or placebo on muscle strength in postmenopausal women were eligible. The quality of studies was assessed using the Cochrane risk of bias tool. Measurements of changes in muscle strength compared to baseline were extracted for pooled analysis. The effect size was calculated as standardized mean differences using a random effects model. RESULTS: We identified nine studies with a combined population of 2,476 postmenopausal women. The studies included were assessed to be of good quality overall. The results showed that HT was not associated with muscle strength gain in postmenopausal women (standardized mean difference = 0.352; 95% confidence interval, -0.098 to 0.803; P = 0.125; I = 95.3%). The changes in muscle strength in women receiving HT were not significant. The results were unchanged when stratified by treatment type, muscle group, and treatment duration. CONCLUSIONS: The use of HT was not associated with the improvement of muscle strength in postmenopausal women. This finding suggested that HT might not improve muscle strength or that the effect size was too small to identify significant therapeutic efficacy.

[Value of color Doppler flow imaging in the diagnosis of subclinical varicocele].

OBJECTIVE: To identify the value of color Doppler flow imaging (CDFI) in the diagnosis of sterility caused by subclinical varicocele (SVC). METHODS: The spermatic veins of 56 sterile patients with seminal abnormality were examined with CDFI and the internal diameters and the time of blood reflux of pampiniform plexus of the veins were observed. In addition, selective X-ray examination of internal spermatic veins was performed for contrast analysis. RESULTS: The diameter of the pampiniform plexus was (2.24 +/- 0.16) mm under the static condition and (2.67 +/- 0. 26) mm during the Valsalva test. The time of blood reflux was (1 487 +/- 203.66) ms. The accuracy of CDFI for diagnosing SVC was 92.8%. CONCLUSION: CDFI has been proved of more value in the diagnosis of SVC than that of clinical varicocele in the etiological screening of male sterility.