BACKGROUND:Previous studies of the research group have found that icariin-containing serum can delay the progression of knee osteoarthritis,promote chondrocyte proliferation and stem cell cartilage differentiation in rats,but there is still a lack of sufficient basis for clinical application.OBJECTIVE:To investigate the repair effect of icariin-containing serum on lipopolysaccharide-induced inflammatory damage of human chondrocytes.METHODS:The effect of icariin-containing serum on chondrocyte viability was detected by cell counting kit-8 method,and the optimal volume fraction and time of icariin-containing serum were screened.The cells were then divided into blank group,lipopolysaccharide group,icariin-containing serum group and lipopolysaccharide+icariin-containing serum group.After grouping,immunofluorescence was used to detect the secretion of type Ⅱ collagen in chondrocytes in each group.Real-time PCR was used to detect the expression of related genes.RESULTS AND CONCLUSION:(1)Icariin-containing serum showed good biosafety characteristics for human chondrocytes,and the cell viability reached the highest level after 48 hours of intervention when the icariin-containing serum volume fraction was 15％,and the follow-up experiments were carried out according to the conditions.(2)Compared with the blank group,lipopolysaccharide significantly inhibited the expression of type Ⅱ collagen in chondrocytes,while icariin-containing serum showed a positive mobilization effect,which could effectively promote the secretion of type Ⅱ collagen in chondrocytes under normal and inflammatory conditions.(3)The mRNA expression of type Ⅱ collagen and Aggrecan in chondrocytes decreased significantly under lipopolysaccharide stimulation,and the mRNA expression levels of matrix metalloproteinase 13 and a disintegrin-like and metalloproteinase with thrombospondin motifs-5 increased significantly.Icariin-containing serum promoted the mRNA expression of type Ⅱ collagen in human chondrocytes under inflammatory conditions and reduced the mRNA expression of matrix metalloproteinase 13 and a disintegrin-like and metalloproteinase with thrombospondin motifs-5 in chondrocytes after lipopolysaccharide intervention.Therefore,these findings indicate that the icariin-containing serum has good safety for human chondrocytes and plays an important role in maintaining the normal physiological functions of chondrocytes,promoting the synthesis of extracellular matrix,and inhibiting the secretion of inflammatory factors.

BACKGROUND:Previous studies of the research group have found that icariin-containing serum can delay the progression of knee osteoarthritis,promote chondrocyte proliferation and stem cell cartilage differentiation in rats,but there is still a lack of sufficient basis for clinical application.OBJECTIVE:To investigate the repair effect of icariin-containing serum on lipopolysaccharide-induced inflammatory damage of human chondrocytes.METHODS:The effect of icariin-containing serum on chondrocyte viability was detected by cell counting kit-8 method,and the optimal volume fraction and time of icariin-containing serum were screened.The cells were then divided into blank group,lipopolysaccharide group,icariin-containing serum group and lipopolysaccharide+icariin-containing serum group.After grouping,immunofluorescence was used to detect the secretion of type Ⅱ collagen in chondrocytes in each group.Real-time PCR was used to detect the expression of related genes.RESULTS AND CONCLUSION:(1)Icariin-containing serum showed good biosafety characteristics for human chondrocytes,and the cell viability reached the highest level after 48 hours of intervention when the icariin-containing serum volume fraction was 15％,and the follow-up experiments were carried out according to the conditions.(2)Compared with the blank group,lipopolysaccharide significantly inhibited the expression of type Ⅱ collagen in chondrocytes,while icariin-containing serum showed a positive mobilization effect,which could effectively promote the secretion of type Ⅱ collagen in chondrocytes under normal and inflammatory conditions.(3)The mRNA expression of type Ⅱ collagen and Aggrecan in chondrocytes decreased significantly under lipopolysaccharide stimulation,and the mRNA expression levels of matrix metalloproteinase 13 and a disintegrin-like and metalloproteinase with thrombospondin motifs-5 increased significantly.Icariin-containing serum promoted the mRNA expression of type Ⅱ collagen in human chondrocytes under inflammatory conditions and reduced the mRNA expression of matrix metalloproteinase 13 and a disintegrin-like and metalloproteinase with thrombospondin motifs-5 in chondrocytes after lipopolysaccharide intervention.Therefore,these findings indicate that the icariin-containing serum has good safety for human chondrocytes and plays an important role in maintaining the normal physiological functions of chondrocytes,promoting the synthesis of extracellular matrix,and inhibiting the secretion of inflammatory factors.

Natural antimicrobial peptides(AMPs)are promising candidates for the development of a new gener-ation of antimicrobials to combat antibiotic-resistant pathogens.They have found extensive applications in the fields of medicine,food,and agriculture.However,efficiently screening AMPs from natural sources poses several challenges,including low efficiency and high antibiotic resistance.This review focuses on the action mechanisms of AMPs,both through membrane and non-membrane routes.We thoroughly examine various highly efficient AMP screening methods,including whole-bacterial adsorption binding,cell membrane chromatography(CMC),phospholipid membrane chromatography binding,membrane-mediated capillary electrophoresis(CE),colorimetric assays,thin layer chromatography(TLC),fluorescence-based screening,genetic sequencing-based analysis,computational mining of AMP data-bases,and virtual screening methods.Additionally,we discuss potential developmental applications for enhancing the efficiency of AMP discovery.This review provides a comprehensive framework for identifying AMPs within complex natural product systems.

Objective:To evaluate the mediating effect of electrocardiographic (ECG) indicators in the association between short-term exposure to fine particulate matter (PM 2.5) and blood pressure and to explore the key PM 2.5 element constituents that produce the mediating effect. Methods:Based on a cross-sectional survey across 10 cities in the Beijing-Tianjin-Hebei region and surrounding areas, PM 2.5 and its element constituents were collected from the nearest air monitoring superstation. Blood pressure and ECG indicators of participants were obtained through physical examinations. A multivariate linear regression was used to evaluate the effect of short-term exposures to PM 2.5 on blood pressure. A mediation analysis was used to identify the mediating effect of ECG indicators in the association between exposure to PM 2.5 and its element constituents and blood pressure. Results:The age of the 1 793 participants was (65.1±13.3) years, and 885 (49.4%) were males. During the study period, the daily mean concentration of PM 2.5 was (70±45) μg/m 3, and the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and pulse pressure (PP) were (139±20), (82±11), (101±13), and (57±17) mmHg (1 mmHg=0.133 kPa), respectively. The results of the multivariate linear regression showed that for every 10 μg/m 3 increase in PM 2.5 on the same day (lag 0), DBP increased by 0.15 (95% CI: 0.02-0.28) mmHg, and PP decreased 0.18 (95% CI: 0.36-0.01) mmHg. The exposure to 14 elemental constituents, such as Ga, Co and Se, was associated with an increase in DBP, while the exposure to 17 elemental constituents, such as Cs, Se and Ag, was associated with a decrease in PP. At lag 0, the PM 2.5-induced increase in DBP was mediated by the QRS interval (mediation percentage of 18.98%), and the PM 2.5-induced decrease in PP was mediated by the QT interval (mediation percentage of -6.31%). The exposure to K, Br, Pb, Zn, Ca, Co, Pd, Cu, and As constituents was associated with increases in DBP mediated by prolonged QRS interval. The exposure to Pb, Zn, K, and As constituents was associated with decreases in PP mediated by prolonged QRS interval. Conclusion:ECG indicators such as QRS interval may mediate the association between short-term exposure to PM 2.5 and its element constituents and blood pressure.

Objective:To assess the effect of short-term exposures to atmospheric fine particulate matter (PM 2.5) and its components on cognitive function in middle-aged and older people aged 40-89 and identify key components that affect cognitive function. Methods:From October 2018 to March 2019, a cross-sectional survey of middle-aged and older people aged 40-89 was conducted across 10 cities in Beijing-Tianjin-Hebei and neighboring regions of China. Data on PM 2.5 and its components were collected from the nearest air supermonitoring stations to the residential addresses. The cognitive function was assessed using the Min-Mental State Examination (MMSE) scale. Multiple linear regression models were used to assess the effect of short-term exposures to PM 2.5 and its components on cognitive function in middle-aged and older people. The restricted cubic spline function was used to fit the exposure-response relationship between different components and changes in MMSE scores. Results:The age of the 1 978 respondents was (65.1±13.4) years, and 976 (49.34%) were males. During the study period, the daily mean concentration of PM 2.5 was (71.2±43.2) μg/m 3, and the MMSE score was (28.2±3.7). The results of the multiple linear regression model showed that short-term exposures to PM 2.5 and its components were associated with cognitive decline in middle-aged and older people after adjusting for confounding factors, and the effect was higher at lag 0-28 days. For an interquartile range (64.3 μg/m 3) increase in PM 2.5 at lag 0-28 d, the MMSE score decreased by 5.91 (95% CI: 0.04, 11.77). For an interquartile range increase in organic carbon (OC), antimony (Sb), chromium (Cr), zinc (Zn), tin (Sn), and cadmium (Cd), the MMSE scores of middle-aged and older people decreased by 5.71 (95% CI: 1.69, 9.73), 4.67 (95% CI: 2.50, 6.84), 4.49 (95% CI: 1.05, 7.92), 3.65 (95% CI: 0.89, 6.42), 2.76 (95% CI: 1.22, 4.30), and 1.72 (95% CI: 0.53, 2.92). Conclusions:Short-term exposures to atmospheric PM 2.5 and its components (OC, Sb, Cr, Zn, Sn, and Cd) are associated with cognitive decline in middle-aged and older people.

Objective:To investigate the acute effects of persistent high exposure to atmospheric fine particulate matter (PM 2.5) on residents' outpatient visits for respiratory diseases. Methods:We collected daily outpatient records from 92 hospitals in 13 cities across the Beijing-Tianjin-Hebei region, along with daily PM 2.5, nitrogen dioxide (NO 2), and meteorological data from 2013 to 2018. Five persistent high PM 2.5 exposure scenarios were defined in terms of daily mean PM 2.5 concentrations (>75 μg/m 3 and >150 μg/m 3), duration (≥2 days and ≥3 days), and whether or not there was concurrent exposure to high levels of NO 2 (daily mean NO 2 concentration >50 μg/m 3). A two-stage statistical analysis strategy based on a generalized linear model was applied to conduct a time-series analysis to assess the exposure-response relationship between persistent high PM 2.5 exposure scenarios and residents' outpatient visits for a variety of respiratory diseases, and to estimate excess outpatient visits. Results:During the period, M ( Q1, Q3) PM 2.5 and NO 2 concentrations were 61.2 (42.3, 95.1) μg/m 3 and 40.2 (31.4, 54.4) μg/m 3, respectively, and the daily respiratory disease outpatient visits were 57 (52, 66) cases. When compared with non-permanent high PM 2.5 exposure periods, exposure scenarios with PM 2.5 >75 μg/m 3 and lasting for ≥2 days caused an increased risk of outpatient visits for respiratory diseases by 2.10% (95% CI: 1.44%-2.77%), and resulted in 43 787 (95% CI: 30 025-57 757) excess visits; in this scenario, the concurrent exposure to high levels of NO 2 had a greater acute effect on respiratory disease visits than the absence of exposure to high levels of NO 2 ( P<0.001). The risk of respiratory disease visits increased substantially by 4.41% (95% CI: 3.15%-5.68%) when the daily mean PM 2.5 concentration exceeded 150 μg/m 3 for ≥2 days. Subgroup disease analyses showed that scenarios with daily mean PM 2.5 concentrations exceeding 75 μg/m 3 for ≥3 days caused a significant increase in the risk of lower respiratory tract infections, chronic lower respiratory disease, and asthma visits. Conclusions:Sustained persistent high PM 2.5 exposure increases the risk of outpatient visits for various respiratory diseases; concurrent exposure to high concentrations of NO 2 leads to a greater risk of visiting the clinic, suggesting that the prevention and control of PM 2.5 pollution should be synchronized with the control of mobile source emissions, to synergistically manage the compound pollution of PM 2.5 and NO 2 in the atmosphere.

Infertility is a common reproductive disorder affecting millions of couples worldwide. It is estimated that male factors account for about 30%-50% of infertility cases, and some studies have found that the concentration of male sperm gradually decreases over time, a trend that suggests the importance of male fertility. Many factors contribute to the decline of male fertility, among which environmental factors have received widespread attention. After reaching adulthood, spermatogonial stem cells will continue to produce sperm, but these cells exist outside the blood testicular barrier, which makes them highly sensitive to environmental conditions such as air pollution, tobacco smoke, radiation, and heavy metals. It is reported that exposure to these adverse environmental factors not only causes oxidative stress and DNA damage to germ cells, but also leads to abnormal epigenetic modification of sperm DNA, thereby causing a series of diseases. This article reviewed the abnormal methylation changes in DNA associated with exposure to environmental pollutants during spermatogenesis and how these changes affect the quantity, quality, and function of spermatozoa.

Natural antimicrobial peptides (AMPs) are promising candidates for the development of a new generation of antimicrobials to combat antibiotic-resistant pathogens. They have found extensive applications in the fields of medicine, food, and agriculture. However, efficiently screening AMPs from natural sources poses several challenges, including low efficiency and high antibiotic resistance. This review focuses on the action mechanisms of AMPs, both through membrane and non-membrane routes. We thoroughly examine various highly efficient AMP screening methods, including whole-bacterial adsorption binding, cell membrane chromatography (CMC), phospholipid membrane chromatography binding, membrane-mediated capillary electrophoresis (CE), colorimetric assays, thin layer chromatography (TLC), fluorescence-based screening, genetic sequencing-based analysis, computational mining of AMP databases, and virtual screening methods. Additionally, we discuss potential developmental applications for enhancing the efficiency of AMP discovery. This review provides a comprehensive framework for identifying AMPs within complex natural product systems.