Association between dietary consumption of fatty acids and age-related macular degeneration in the National Health and Nutrition Examination Survey.

The aim of this study is to assess the relationship between dietary intake of fatty acids and the age-related macular degeneration (AMD) in the United States population. Adult participants of the 2005-2008 National Health and Nutrition Examination Survey (NHANES) were included in this nationwide cross-sectional study. Dietary fatty acid intake was obtained from two 24-h dietary recall interviews. The intake of dietary fatty acids was analyzed as a continuous and categorical variable. AMD status was assessed using nonmydriatic fundus photographs. Univariate and multivariate logistic regression analyses were used to assess the association between dietary fatty acid intake and AMD. The unweighted population included 4702 individuals of whom 374 had AMD. After adjusting for relevant variables, each 1 unit increase (1 mg/1000 kcal) intake of EPA (OR: 0.996, 95% CI: 0.993-0.996, P = 0.018), DPA (OR: 0.976, 95% CI: 0.962-0.990, P = 0.002), and DHA (OR: 0.996, 95% CI: 0.994-0.999, P = 0.003) were significantly decreased odds of any AMD. The highest versus lowest quartile of EPA (OR: 0.476, P for trend < 0.001), DPA (OR: 0.467, P for trend = 0.005) and DHA (OR: 0.586, P for trend = 0.008) were negatively associated with the odds of any AMD. Subgroup analysis showed that higher quartiles of EPA (OR: 0.461, P for trend < 0.002), DPA (OR: 0.467, P for trend = 0.006) and DHA (OR: 0.578, P for trend = 0.007) exhibited a negative association with early AMD. The study found no significant association between the intake of dietary fatty acids, including n-3 PUFA, and the odds of late AMD. In the 2005-2008 NHANES population, higher dietary DHA, DPA and EPA intake associated with decreased odds of early AMD. However, no clear association was found between specific types of FAs and late AMD.

MiR-34a ameliorates arterial blood flow in rats with lower limb arteriosclerosis obliterans via Sirt1 signaling pathway.

In this study, we investigated the impact of microRNA-34a (miR-34a) on lower limb arteriosclerosis obliterans in rats through the Sirtuin 1 (Sirt1) signaling pathway. Thirty-six Sprague-Dawley rats were divided into normal, model, and miR-34a mimics groups. Rats in the normal group were raised normally, while the model group underwent lower limb arteriosclerosis obliterans induction and received saline injections. The miR-34a mimics group also underwent arteriosclerosis obliterans modeling but received miR-34a mimics injections. Immunohistochemistry revealed significantly increased vascular endothelial growth factor (VEGF) expression in both model and miR-34a mimics groups compared to the normal group, with the miR-34a mimics group showing higher levels. Western blotting indicated elevated Sirt1 protein expression in both non-normal groups, with the miR-34a mimics group exhibiting significantly higher levels. Quantitative polymerase chain reaction (qPCR) demonstrated higher levels of miR-34a, VEGF mRNA, and Sirt1 mRNA in the model group compared to the normal group, but significantly lower levels than the miR-34a mimics group. Enzyme-linked immunosorbent assay (ELISA) showed increased VEGF content in the model group compared to the normal group but decreased compared to the miR-34a mimics group. Hemorrheological detection revealed a reduced PU index in both non-normal groups compared to the normal group, with a significant increase in the miR-34a mimics group compared to the model group. Overall, miR-34a upregulation enhanced VEGF expression in rat blood vessels, ameliorating arterial blood flow in lower limb arteriosclerosis obliterans through the Sirt1 signaling pathway.

Monoterpenoid indole alkaloids from Melodinus axillaris W.T.Wang exhibit anti-inflammatory activities by inhibiting the NF-κB signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Melodinus axillaris W.T.Wang has been widely used as an important medicine in China. In the folk of China, its whole plant has been used for fractures, rheumatic heart disease, testitis, hernia, abdominal pain, and dyspepsia, etc. Despite its extensive use, there is a shortage of literature investigating the specific bioactive compounds and underlying mechanisms responsible for their anti-inflammatory effects. This knowledge gap serves as the primary impetus for conducting this study, which aims to shed light on the previously unexplored therapeutic potential of M. axillaris. AIM OF THE STUDY: This study aims to investigate the material basis and potential mechanism of anti-inflammatory activity of M. axillaris. MATERIALS AND METHODS: Compounds were isolated from the 95% ethanol extract of M. axillaris using a systematic phytochemical method. The structures were established by extensive spectroscopic analysis, including 1D and 2D NMR, HR-ESI-MS, ECD calculation, and DP4+ analysis. The anti-inflammatory activities of ethanol extract and compounds from M. axillaris were tested by an inflammation model of LPS-stimulated RAW264.7 cells in vitro. Western blot analysis was employed to evaluate the expressions of COX-2, iNOS, and NF-κB signaling pathways, aiming to elucidate the underlying mechanisms. RESULTS: Eleven undescribed monoterpenoid indole alkaloids (MIAs), axillines A-K (1-11), along with thirteen known analogs were isolated from M. axillaris. Compound 1 was the first representative of vincadine alkaloid with unprecedented 6/5/9/6/6 skeletons. Compounds 1-11 and ethanol extract showed significant anti-inflammatory effects in vitro. Among them, compound 2 had the best activity of inhibiting NO release (IC50 = 3.7 ± 0.9 µM). Additionally, subsequent Western blot analysis revealed that 2 could significantly inhibit the up-regulation of NF-κB signaling pathways, iNOS, and COX-2 in LPS-stimulated RAW264.7 cells, thereby demonstrating its anti-inflammatory activity. CONCLUSION: This study provides support for the traditional use of M. axillaris in terms of its anti-inflammatory properties and highlights the potential of MIAs as promising candidates for further development as anti-inflammatory drugs.

Undescribed compounds from Clinopodium chinense (Benth.) O. Kuntze and their coagulation activity studies.

Four rare compounds (1-4), including one 1,4-epoxy-benzoxepane derivative and one ringed prenylated naphthoquinoid skeleton, as well as one isopimarane-type diterpenoid and one megastigmane-type glycoside, along with three known megastigmane-type glycosides (5-7) were isolated from the ethanol extracts of C. chinense. Their structures were determined on the basis of 1D, 2D NMR, HR-ESI-MS and DP4+ analysis. Meanwhile, the in vitro evaluation indicated that compound 2 and 6 exhibited excellent procoagulant activities, which can significantly shorten prothrombin time (PT) and activated partial thromboplastin time (APTT), respectively.

Monoterpenoid indole alkaloid dimers from the Melodinus axillaris induce G2/M phase arrest and apoptosis via p38 MAPK activation in HCT116 cells.

Four monoterpenoid indole alkaloid dimers (MIADs), axidimins A-D (1-4), which possesses unprecedented apidosperma-aspidosperma-type skeletons, along with twelve known MIAs were isolated from Melodinus axillaris. Their structures were established by comprehensive analysis of the HRESIMS, NMR, ECD calculation and DP4 + analysis. A possible biosynthetic pathway for axidimins A-D was proposed. In vitro, axidimins C and D exhibited significant cytotoxicities against HCT116 cells with IC50 values of 5.3 µM and 3.9 µM, respectively. The results obtained from flow cytometry and Western blot analysis clearly demonstrated that axidimins C and D significantly induced a reverse G2/M phase arrest and apoptosis of HCT116 cells. The potential mechanism of axidimins C and D on HCT116 cells were thoroughly discussed through the utilization of network pharmacology and molecular docking research. Subsequently, the selected targets were validated using Western blot and CETSA analysis, confirming that axidimins C and D exert its cytotoxic effects through the activation of the p38 MAPK pathway, ultimately leading to HCT116 cells death. This study provides evidence indicating that axidimins C and D have the potential to induce cell cycle arrest and apoptosis in HCT116 cells by modulating the p38 MAPK signaling pathway. These findings offer a novel perspective for the development of anti-colorectal cancer drugs.

Three Undescribed Flavonoids and Amide from Abrus mollis Hance with Hepatoprotective Effects.

Through a phytochemical investigation of Abrus mollis Hance, a folk medicinal plant in China, we isolated and identified three undescribed compounds, including two flavonoids and one amides alkaloid, along with nine known from this plant. Their structures were elucidated by analyses of 1D, 2D NMR, HR-ESI-MS, ECD, and DP4+ analysis. Furthermore, we evaluated the hepatoprotective effects of all twelve compounds on D-GalN-induced Brl-3 A cells. According to the results, at a concentration of 25 µM, the cell survival rates were observed to be 71.92±0.34 %, 70.03±1.29 %, and 69.11±1.90 % for compound 2, 4, and 11, respectively. Further experimental studies showed that compound 2 (EC50 5.76±0.37 µM) showed more significant protective activity than the bicyclol.

The causal effect of obesity on diabetic retinopathy: A two-sample Mendelian randomization study.

Background: The causal effect of obesity on diabetic retinopathy (DR) remains controversial. The aim of this study was to assess the causal association of generalized obesity evaluated by body mass index (BMI) and abdominal obesity evaluated by waist or hip circumference with DR, background DR, and proliferative DR using a two-sample Mendelian randomization (MR) analysis. Methods: Genetic variants associated with obesity at the genome-wide significance (P<5×10-8) level were derived using GWAS summary statistics from the UK Biobank (UKB) with a sample size of 461 460 individuals for BMI, 462 166 individuals for waist circumference, and 462 117 individuals for hip circumference. We obtained genetic predictors of DR (14 584 cases and 202 082 controls), background DR (2026 cases and 204 208 controls), and proliferative DR (8681 cases and 204 208 controls) from FinnGen. Univariable and multivariable Mendelian randomization analyses were conducted. Inverse variance weighted (IVW) was the main method used to analyze causality, accompanied by several sensitivity MR analyses. Results: Genetically predicted increased BMI [OR=1.239; 95% CI=(1.134, 1.353);P=1.94×10-06], waist circumference [OR=1.402; 95% CI=(1.242, 1.584); P=5.12×10-08], and hip circumference [OR=1.107; 95% CI=(1.003, 1.221); P=0.042] were associated with increased risk of DR. BMI [OR=1.625; 95% CI=(1.285, 2.057); P=5.24×10-05], waist circumference [OR=2.085; 95% CI=(1.54, 2.823); P=2.01×10-06], and hip circumference [OR=1.394; 95% CI=(1.085, 1.791); P=0.009] were correlated with the risk of background DR. MR analysis also supported a causal association between BMI [OR=1.401; 95% CI=(1.247, 1.575); P=1.46×10-08], waist circumference [OR=1.696; 95% CI=(1.455, 1.977); P=1.47×10-11], and hip circumference [OR=1.221; 95% CI=(1.076, 1.385); P=0.002] and proliferative DR. The association of obesity with DR continued to be significant after adjustment for type 2 diabetes. Conclusion: This study using two-sample MR analysis indicated that generalized obesity and abdominal obesity might increase the risk of any DR. These results suggested that controlling obesity may be effective in DR development.

The causal relationship between COVID-19 and increased intraocular pressure: A bidirectional two-sample Mendelian randomization study.

Background: Coronavirus disease 2019 (COVID-19) has brought great challenges to the global public health system and huge economic burdens to society, the causal effect of COVID-19 and intraocular pressure was blank. Objective: This study aimed to explore the causal association between coronavirus disease (COVID-19) susceptibility, severity and criticality and intraocular pressure (IOP) by bidirectional Mendelian randomization (MR) analysis. Materials and methods: Genetic associations with COVID-19 susceptibility, severity and criticality were obtained from the COVID-19 Host Genetics Initiative. Genetic associations with IOP were obtained from GWAS summary data. The standard inverse variance weighted (IVW) method was used in the primary assessment of this causality. Other methods were also implemented in supplementary analyses. Finally, sensitivity analysis was performed to evaluate the reliability and stability of the results. Results: The results showed that COVID-19 susceptibility had null effect on IOP (ß = 0.131; Se = 0.211; P = 0.533) as assessed by the IVW method. Moreover, the results revealed that COVID-19 severity, specifically, hospitalization due to COVID-19, had a positive effect on IOP with nominal significance (ß = 0.228; Se = 0.116; P = 0.049). However, there were null effect of COVID-19 criticality on IOP (ß = 0.078; Se = 0.065; P = 0.227). Sensitivity analysis showed that all the results were reliable and stable. The reverse MR analysis revealed that there was null effect of IOP on COVID-19. Conclusions: We demonstrated that hospitalization due to COVID-19 might increase IOP; therefore, greater attention should be given to monitoring IOP in inpatients with COVID-19.

Plasma lipid levels and risk of retinal vascular occlusion: A genetic study using Mendelian randomization.

The causal effects of plasma lipid levels and the risk of retinal vascular occlusion (RVO) have not been clearly identified, especially for high-density lipoprotein-cholesterol (HDL-C) and low-density lipoprotein-cholesterol (LDL-C). Here, we try to identify these causal risk factors using a two-sample Mendelian randomization (MR) analysis. Single nucleotide polymorphisms (SNPs) were chosen as instrumental variables (IVs). We obtained genetic variants associated with lipid exposure at the genome-wide significance (P<5×10-8) level from a meta-analysis of GWAS from the Global Lipids Genetics Consortium (GLGC) based on 188,577 individuals of mostly European ancestry for MR analyses. Meanwhile, we used lipid GWAS from UK Biobank (UKB) with a sample size of 115,078 individuals as a supplement. We obtained genetic predictors of RVO from a FinnGen biobank study. We conducted both univariable and multivariable MR (MVMR) analyses to identify the causal effects of RVO. Although inverse variance weighted (IVW) was the primary method used for MR analyses, MR-Egger and weighted-median methods were used as supplements to IVW. We determined the heterogeneity of IVs using Cochrane's Q test and I2 , and used the MR-Egger intercept and MR-PRESSO Global test to detect horizontal pleiotropy. A leave-one-out sensitivity analysis was conducted by removing a single variant from the analysis. Genetically predicted increased HDL-C level was associated with decreased risk of RVO from GLGC [OR=0.806; 95% CI=(0.659, 0.986); P=0.036], which was consistent with UKB results [OR=0.766; 95% CI=(0.635, 0.925); P=0.005]. MVMR analysis for plasma lipids [adjusted OR=0.639; 95% CI=(0.411, 0.992); P=0.046] or diabetes [adjusted OR=0.81; 95% CI=(0.67, 0.979); P=0.029] suggested that low HDL-C may be an independent risk factor for RVO. However, there was no evidence to support a causal association between LDL-C {GLGC [adjusted OR=1.015; 95% CI=(0.408, 2.523); P=0.975], UKB [OR=1.115; 95% CI=(0.884, 1.407); P=0.359]}, total cholesterol {GLGC [adjusted OR=0.904; 95% CI=(0.307, 2.659); P=0.854], UKB [OR=1.047; 95% CI=(0.816, 1.344); P=0.716]} or triglycerides {GLGC [OR=1.103; 95% CI=(0.883, 1.378); P=0.385], UKB [OR=1.003; 95% CI=(0.827, 1.217); P=0.098]} and RVO. Using two-sample MR analysis, our study suggested that dyslipidemia was a risk factor for RVO. Furthermore, our results indicated that a low HDL-C level may be an independent risk factor for RVO, suggesting that controlling HDL-C level may be effective in RVO development.

Topical administration of diminazene aceturate decreases inflammation in endotoxin-induced uveitis.

PURPOSE: Our previous study demonstrated that an intraperitoneal injection of Diminazene Aceturate (DIZE) attenuated uveitis by activating ocular angiotensin-converting enzyme 2 (ACE2). Here, we investigated the anti-inflammatory effects on the ocular anterior segment of a topical administration of a DIZE solution and explored the downstream target molecules involved in the anti-inflammatory mechanism after ACE2 activation. METHODS: Endotoxin-induced uveitis (EIU) in rats was induced by a subcutaneous injection of lipopolysaccharides (LPS, 200 µg) in 0.1 ml of sterile saline. DIZE (0.025, 0.05, or 0.1%) and dexamethasone (0.1%) solutions were applied topically (10 µl eyedrops) to both eyes 6X every two hours before and after LPS injection. The inflammation of the ocular anterior segment was observed and the clinical scores were evaluated 24 h after LPS injection. The total protein concentration and levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the aqueous humor were determined. CD11b-positive cells adjacent to the iris ciliary body (ICB) were stained by immunohistochemistry. The mRNA levels of inflammatory cytokines and mediators, including IL-1ß, TNF-α, COX-2, and iNOS or NF-κB subunit p65 in the ICB, were analyzed by real time RT-PCR. The protein expression of NF-κB p65 and the phosphorylated protein of p38 MAPK were detected by western blotting. RESULTS: A topical administration of DIZE decreased clinical scores and the total protein concentration, as well as TNF-α and IL-6 levels in the aqueous humor. Meanwhile, the mRNA levels of inflammatory cytokines and mediators, including IL-1ß, TNF-α, COX-2, and iNOS in the ICB, were downregulated. DIZE reduced the recruitment of CD11b-positive cells adjacent to the ICB. Furthermore, DIZE downregulated the expressions of NF-κB subunit p65 at protein and mRNA levels and inhibited the phosphorylation of p38 MAPK protein in the ICB. CONCLUSIONS: A topical administration of DIZE suppressed ocular inflammation in EIU and decreased the levels of inflammatory cytokines. DIZE attenuated the activation of NF-κB and p38 MAPK in EIU, which may be associated with ACE2-mediated anti-inflammatory effects. Our data provided further evidence that DIZE may represent a novel class of drug for the management of ocular inflammation.

Activation of liver X receptor protects inner retinal damage induced by N-methyl-D-aspartate.

PURPOSE: To investigate whether activation of liver X receptors (LXRs) protects N-methyl-D-aspartic (NMDA)-induced retinal neurotoxicity in mice and to explore the underlying mechanism. METHODS: Inner retinal damage was induced by intravitreal injection of NMDA. A synthetic LXR ligand TO901317 (TO90, 50 mg/kg/d) or vehicle was intragastrically administrated from 3 days before to 1 day or 7 days after NMDA injection. The severity of retinal damage was evaluated with histological analysis and TUNEL staining, and retinal functions were evaluated by ERG. The expressions of caspase-3, bax, bcl-2, TNF-α, and BACE1, the rate-limiting enzyme in the formation of amyloid ß (Aß), in the retina were examined by real-time PCR and ELISA. The levels of LXRs, NF-κB subunit p65, p-p38 mitogen-activated protein kinase (MAPK), and an LXR target gene ABCA1 were detected with real-time PCR and Western blotting. The localization and protein expression of Aß in the retina was assessed by immunohistochemistry and Western blotting. RESULTS: The NMDA enhanced the expression of LXRß but not LXRα and ABCA1 in mouse retina. Nevertheless, administration of TO90 after NMDA injection not only enhanced the expression of LXRß but also upregulated the level of ABCA1, suggesting retinal LXRs were activated in a ligand-dependent manner. The LXRα expression was unchanged in the vehicle and the TO90-treated groups. Activation of LXRß with TO90 inhibited cell death in the ganglion cell layer (GCL) and inner nuclear layer (INL), preserved ERG b- and a-wave amplitudes, and the b/a ratio in the NMDA-treated mice. Meanwhile, TO90 suppressed the elevation of apoptosis factors caspase-3 and bax induced by NMDA and upregulated the level of an antiapoptotic factor bcl-2. The TO90 also inhibited the increase of p-p38 MAPK and proinflammatory cytokine TNF-α after NMDA injection. Furthermore, activation of LXR attenuated the activation of NF-κB, and reduced gene expression of BACE1 and accumulation of Aß induced by NMDA. CONCLUSIONS: Activation of LXRß with a synthetic LXR ligand TO90 protects the inner retinal damage induced by NMDA in mice. We speculate the protective effect is associated with inhibition of the NF-κB signaling pathway and reduction of Aß formation in retina. The LXR agonists may become a new class of neuroprotective agent for retinal diseases associated with glutamate-induced excitotoxicity.

[The extraction and analysis of a- and b- wave from electroretinogram in human].

OBJECTIVE: To determine the frequency range of a-b wave complex in the dark- and light-adapted electroretinogram (ERG) and to isolate the pure a- and b- waves. METHODS: Case series study. Full-field ERGs were recorded in 16 eyes of 8 normal volunteers from October to November 2011. Digital filtering technique was used to extract the a- and b-waves from dark- and light-adapted ERG responses. The timings of a- and b-wave were measured to determine the frequency range of a-b wave complex. Major frequency components were determined from power spectra using fast Fourier transform (FFT). The effect of different order settings in the digital filter were compared to investigate the optimum condition, where the oscillatory potential (OP) was completely removed while the amplitudes and phases of the a- and b- waves were less affected. The Student-t test was used to compare the frequency range of a-b wave complex in dark- and light-adapted ERG. RESULTS: The averaged frequency range of the dark-adapted a-b wave complex was from (14.99 ± 2.39) to (25.35 ± 3.77) Hz, compared with (25.22 ± 6.56) to (32.47 ± 3.68) Hz for the light-adapted a-b wave complex, respectively, indicating the frequency range of the dark-adapted a-b wave complex was significantly less than the light-adapted a-b wave complex (t = 7.910, 7.693; both P < 0.01). The third order of the digital filter and a passband of 1 to 45 Hz was the best choice in term of removing the high frequency OP from the waveform of ERG and keeping the amplitude and phase of the a- and b- waves. CONCLUSIONS: The frequency of a-b wave complex is lower than that of OP. Therefore the a- and b- waves can be isolated from OP using different digital filter settings in human ERG. A third order and a passband of 1 to 45 Hz is the best choice to extract pure a- and b- waves from the original ERG.