Objective To explore the effect of physical exercise on semen quality in order to provide basic data and theoretical basis for the improvement of male reproductive health. Methods A cross-sectional study was conducted on 1 059 males who visited the Reproductive Medicine Center of Shandong Maternal and Child Health Hospital for medical treatment and physical examination during July 2022 and April 2023. Their demographic data and physical exercise data were surveyed with questionnaires. Total sperm count, sperm concentration, total sperm motility, forward movement and normal sperm morphology were analyzed with computer aided analysis. Logistic regression model and multiple linear regression model were applied to analyze the effects of physical exercise on semen quality. Results After adjustment for confounding factors such as age, body mass index, alcohol consumption and smoking, logistic regression analysis showed that the risk of abnormal semen quality was increased in patients with moderate and heavy exercise intensity (OR=2.103, OR=2.229). Compared with the participants with physical exercise ≤10 min per session, those with >20 min per session had a lower risk of abnormal semen quality (OR=0.357, 0.256, 0.289 for exercise time for >20~30, >30~60, >60 min, respectively). There was no statistical significance between physical exercise frequency and semen quality (P>0.05). The participants having exercise well were at a lower risk for abnormal semen quality (OR=0.711). Multiple linear regression analysis revealed that the frequency of physical exercise was an influencing factor of sperm concentration (β=7.474, 95%CI: 4.800~10.149, P<0.05); the time of physical exercise per session was an influencing factor for total sperm count (β=20.632, 95%CI: 7.634~33.629); the intensity of physical exercise (β=-1.461, 95%CI: -2.392~-0.530) and time of physical exercise per session (β=2.608, 95%CI: 1.404~3.812, P<0.05) were influencing factors for percentage of forward motility sperm (P<0.05); and physical exercise intensity (β=-1.934, 95%CI: -3.238~-0.630), time of physical exercise per session (β=4.211, 95%CI: 2.525~5.897) and frequency of physical exercise (β=-2.008, 95%CI: -3.480~-0.536) were influencing factors of total sperm motility (P<0.05). Conclusion Physical exercise may affect semen quality, greater intensity of physical exercise may be a risk factor for abnormal semen quality, and longer physical exercise time may be related to improving semen quality. Therefore, proper physical exercise can help improve semen quality.

Microcystin-leucine arginine (MC-LR) is a common cyantotoxin produced by hazardous cyanobacterial blooms, and eutrophication is increasing the contamination level of MC-LR in drinking water supplies and aquatic foods. MC-LR has been linked to colorectal cancer (CRC) progression associated with tumor microenvironment, however, the underlying mechanism is not clearly understood. In present study, by using GEO, KEGG, GESA and ImmPort database, MC-LR related differentially expressed genes (DEGs) and pathway- and gene set-enrichment analysis were performed. Of the three identified DEGs (CXCL1, GUCA2A and GDF15), CXCL1 was shown a positive association with tumor infiltration, and was validated to have a dominantly higher upregulation in MC-LR-treated tumor-associated macrophages (TAMs) rather than in MC-LR-treated CRC cells. Both CRC cell/macrophage co-culture and xenograft mouse models indicated that MC-LR stimulated TAMs to secrete CXCL1 resulting in promoted proliferation, migration, and invasion capability of CRC cells. Furtherly, IP-MS assay found that interaction between TAMs-derived CXCL1 and CRC cell-derived IGHG1 may enhance CRC cell proliferation and migration after MC-LR treatment, and this effect can be attenuated by silencing IGHG1 in CRC cell. In addition, molecular docking analysis, co-immunoprecipitation and immunofluorescence further proved the interactions between CXCL1 and IGHG1. In conclusion, CXCL1 secreted by TAMs can trigger IGHG1 expression in CRC cells, which provides a new clue in elucidating the mechanism of MC-LR-mediated CRC progression.

BACKGROUND:The effects of metal exposure on semen quality and the role of oxidative damage in this process remain unclear. METHODS:We recruited 825 Chinese male volunteers, and 12 seminal metals (Mn, Cu, Zn, Se, Ni, Cd, Pb, Co, Ag, Ba, Tl, and Fe), the total antioxidant capacity (TAC), and reduced glutathione were measured. Semen parameters and GSTM1/GSTT1-null genotypes were also detected. Bayesian kernel machine regression (BKMR) was applied to evaluate the effect of the mixed exposure to metals on semen parameters. The mediation of TAC and moderation of GSTM1/GSTT1 deletion were analyzed. RESULTS:Most seminal metal concentrations were correlated with each other. The BKMR models revealed a negative association between the semen volume and metal mixture, with Cd (cPIP = 0.60) and Mn (cPIP = 0.10) as the major contributors. Compared to fixing all scaled metals at their median value (50th percentiles), fixing the scaled metals at their 75th percentiles decreased the TAC by 2.17 units (95%CI: -2.60, -1.75). Mediation analysis indicated that Mn decreased the semen volume, with 27.82% of this association mediated by TAC. Both the BKMR and multi-linear models showed that seminal Ni was negatively correlated with sperm concentration, total sperm count, and progressive motility, which was modified by GSTM1/GSTT1. Furthermore, Ni and the total sperm count showed a negative association in GSTT1 and GSTM1 null males (β[95%CI]: 0.328 [-0.521, -0.136]) but not in males with GSTT1 and/or GSTM1. Although Fe and the sperm concentration and total sperm count were positively correlated, they showed inverse "U" shapes in univariate analysis. CONCLUSION:Exposure to the 12 metals was negatively associated with semen volume, with Cd and Mn as the major contributors. TAC may mediate this process. GSTT1 and GSTM1 can modify the reduction in the total sperm count caused by seminal Ni exposure.

Microcystin-LR (MC-LR) affects bone health in adult mice via osteo-immunomodulation. However, its effect on osteoblasts and bone development is unclear. This study investigated the effect of MC-LR on bone osteoimmune and osteoblasts in the developing period. 18 Four-week-old male Sprague Dawley rats were divided into two groups (n = 9 per group) and exposed to 0 (control) and 1 μg/kg b.w. MC-LR (exposure) by intraperitoneal injection for four weeks. The heart blood was collected for serological examination, and the femur for morphological, histopathological, and biomechanical analysis. MC-LR exposure significantly weakened bone microstructures (bone volume, bone volume/total volume, bone trabecular number, connectivity density) and biomechanics (maximum loads and maximum deflection) (P < 0.05). Besides, MC-LR decreased serum procollagen type І car-boxy-terminal propeptide, osteocalcin, bone morphogenetic protein-2, osteoprotegerin, and receptor activator of nuclear factor κB ligand, while elevating osteoclasts number, matrix metalloproteinase-9, β-catenin, Runt-related transcription factor 2, and osterix in bone, and bone alkaline phosphate, C-terminal cross-linked telopeptide of type-I collagen, tartrate-resistant acid phosphatase-5b in serum (P < 0.05). Moreover, MC-LR increased CD4+ T-cells, CD4+/CD8+, M1 and M2 macrophages, and cells apoptosis in the bone marrow, interleukin-6, interleukin-17, and tumor necrosis factor-α in serum, decreased serum interleukin-10 (P < 0.05). Overall, MC-LR can promote bone resorption by activating osteoclasts via osteoimmunology, which may involve macrophages besides lymphocytes. MC-LR may inhibit bone formation by stopping the osteoblasts at an immature stage. Thus, MC-LR weakened bone microstructure and biomechanics in developing period. Its risk on bone development needs further study.

IntroductionMetabolic acidosis affects bone health. It remains unclear whether drinking natural mineral water is better for maintaining bone health in the youth with metabolic acidosis.Materials and MethodsSixty young female rats (3-weeks-old) were randomly divided into three groups and drank purified water (PW, as control), bicarbonate-rich natural mineral water (Bic-NMW), or sulfate-rich natural mineral water (Sul-NMW), which, respectively, contained calcium (0.17, 155, and 175 mg/L), bicarbonate (0.1360, and 139 mg/L) and sulfate (0, 35.6, and 532 mg/L), for 16 weeks. In the last 3 weeks, metabolic acidosis was induced in 10 rats per group by adding NH4Cl (0.28 mM) to drinking water. The rats' blood, urine, and femur were collected for assessing acid-base status, calcium metabolism, bone microstructure, and strength. The difference between the three groups was determined using one-way ANOVA followed by the Student–Newman–Keuls test or Dunnett's T3 test.ResultsCompared with the PW rats, the Bic-NMW rats and the Sul-NMW rats had less urine net acid excretion (−1.51, 0.20 vs. 10.77, EQ/L), higher bone mineral density (442.50, 407.49 vs. 373.28, mg/mm3), growth cartilage width (271.83, 283.83 vs. 233.27, μm) and cortical trabecular area (9.33, 9.55 vs. 5.05, mm2), and smaller cortical marrow cavity area (5.40, 5.49 vs. 7.27, mm2) in the femur (P < 0.05). Besides, the Bic-NMW rats had less serum calcium (2.53 vs. 2.68, mmol/L) and C-terminal cross-linked telopeptide of type-I collagen (1.35 vs. 1.93, ng/mL), and higher serum calcitonin (0.61 vs. 0.39, μg/L), femoral trabecular thickness (0.10 vs. 0.09, μm), bone volume/total volume (0.42 vs. 0.34, %), cortical bone area (15.91 vs. 12.80, mm2), and ultimate stress (35.12 vs. 29.32, MPa) (P < 0.05). The Sul-NMW rats had more osteoclasts (22.50 vs. 11.54, cells/field) (P < 0.05).ConclusionsDrinking natural mineral water, especially bicarbonate-rich natural mineral water, is effective in improving bone health in young rats with metabolic acidosis. These benefits include maintaining bone mineral density, and improving bone microstructure and biomechanical properties via moderating metabolic acidosis.

Microcystin-LR (MC-LR) exists widely in polluted food and water in humid and warm areas, and facilitates the progression of colorectal cancer (CRC). However, the molecular mechanism associated with the MC-LR-induced CRC progression remains elusive. The purpose of this study is to explore the role of the hub genes associated with MC-LR-induced CRC development at the molecular, cellular and clinical levels through bioinformatics and traditional experiments. By utilizing R, we screened and investigated the differentially expressed genes (DEGs) between the MC-LR and the control groups with the GEO, in which, HOXB4 highly expressed in MC-LR-treated group was identified and further explored as a hub gene. With the aid of TCGA, GEPIA, HPA, UALCAN, Cistrome, and TIMER, the increased mRNA and protein levels of HOXB4 in CRC tissue were found to be positively associated with high tumor stage and poor prognosis, and were linked to immune infiltration, especially tumor-associated macrophages and cancer-associated fibroblasts. Cox regression analysis and nomogram prediction model indicated that high HOXB4 expression was correlated to poor survival probability. To elucidate the mechanism of high HOXB4 expression induced by MC-LR, we overlapped the genes involved in the MC-LR-mediated CRC pathways and the HOXB4-correlated transcription genes. Importantly, C-myc instead of PPARG and RUNX1 promoted the high expression of HOXB4 through experiment validation, and was identified as a key target gene. Interestingly, C-myc was up-regulated by HOXB4 and maintained cell cycle progression. In addition, MC-LR was proved to up-regulate HOXB4 expression, thus promoting proliferation and migration of Caco2 cells and driving the cell cycle progression. In conclusion, MC-LR might accelerate CRC progression. In the process, MC-LR induced C-myc augmentation elevates the high expression of HOXB4 through increasing the S phase cell proportion to enhance Caco2 cell proliferation. Therefore, HOXB4 might be considered as a potential prognostic biomarker for CRC.

Objective To determine whether metformin(Met) inhibits the proliferation of colorectal cancer cells by inducing cell senescence, and to preliminarily explore the underlying mechanism. Methods LOVO and SW480 colorectal cancer cells were treated with different concentrations of Met(0, 2.5, 5.0, 10.0, 20.0 and 40.0 mmol/L). The cell viability was detected by CCK-8 assay, and apoptosis and cell cycle were detected by flow cytometry. According to the results of apoptosis, differences between control group (0 mmol/L) and 5.0 mmol/L Met group(n=3) were compared in following experiments. Cell proliferation was detected by CCK-8 assay, EdU assay, and clone formation assay, senescence metabolism was detected by senescence-associated β-galactosidase(SA-β-gal)staining, protein phosphatase 2A(PP2A) enzyme activity was measured with ELASA, and protein expression was detected with Western blotting. PP2A inhibitor LB-100 was used to treat the cells alone or combined with Met, and then the cells were divided into control group, Met group, Met+LB-100 group, and LB-100 group(n=3). Above experiments were performed again. Results Met treatment significantly inhibited LOVO and SW480 cells proliferation in a concentration- and time-dependent manner(P < 0.05). Under the treatment of low concentration(≤5.0 mmol/L) of Met, the cells presented no obvious apoptosis, but were obviously inhibited for proliferation and arrested at G0/G1 phase. The cells displayed a typical senescence-like morphology of large, flat and vacuolated, and the number of SA-β-gal positive cells was increased significantly. For PP2A, total protein expression showed no change, but phosphorylation level decreased obviously and PP2A activity increased statistically(P < 0.05), in the meantime, the phosphorylation level of downstream AKT protein decreased and senescence-related proteins p53 and P21 increased significantly. Treatment by PP2A inhibitor LB-100 combined with Met significantly reversed the inhibition of Met on cell proliferation and delayed Met-induced cell senescence. Conclusion Low concentration of Met can induce cell senescence through PP2A/AKT pathway and then inhibit the proliferation of colorectal cancer cells.

Background: Nickel is a component of biomedical alloys that is released during corrosion or friction and causes cytotoxicity, mutation, differentiation or even carcinogenesis in tissues. However, the mechanisms underlying the potential hazards of Nickel-containing alloys implanted in the human body by surgery remain uncertain. Objective: To study the effect of Ni(II) (NiCl2 center dot 6H(2)O) on cancer cells. Methods: A549 and RKO cells were treated with various concentrations of Ni(II) to determine the effect of Ni(II) on cellular viability using a CCK8 assay. Flow cytometry was performed to analyze the effect of Ni(II) on apoptosis and the cell cycle. Sphere-forming assays were conducted to examine the stemness properties of A549 and RKO cells. Western blotting was to evaluate the expression levels of SOX2, IDH1, HIF-1 alpha and beta-catenin. The expression of isocitrate dehydrogenase (IDH1) in rectum adenocarcinoma (READ) was analyzed by Gene Expression Profiling Interactive Analysis (GEPIA). Kaplan-Meier analysis was used to calculate the correlation between survival and IDH1 expression. Results: Long-term exposure (120 days) to 100 mu M Ni(II) significantly repressed cell proliferation, decreased colony formation and arrested the cell cycle at the G(0)/G(1) phase. In addition, the stem-like traits of A549 and RKO cells were significantly augmented. Ni(II) also significantly decreased the protein expression of IDH1 and the synthesis rate of NAPDH, which competitively inhibited alpha-ketoglutarate (alpha-KG) generation. The downregulation of IDH1 not only promoted beta-catenin accumulation in the cell nucleus in a HIF-1 alpha signaling-dependent manner but also induced the expression of the transcription factor SOX2 to maintain the stemness properties of cancer cells. Moreover, IDH1 expression negatively correlated with the clinicopathologic characteristics of READ. Conclusion: These findings demonstrate that chronic and continuous release of Ni(II) to the microenvironment suppresses IDH1 expression and augments the stemness properties of cancer cells via the activation HIF-1 alpha/beta-catenin/SOX2 pathway to enhance local tumor recurrence in patients with implanted Nickel-containing alloys at surgical sites.