Arginine, Transsulfuration, and Folic Acid Pathway Metabolomics in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

The impact of homocysteine on patients with diabetic nephropathy: a mendelian randomization study

BACKGROUND/AIMS

Homocysteine (Hcy) has been associated with an increased risk of diabetic nephropathy (DN) in patients, but there is still controversy. This study aims to investigate the causal relationship between plasma Hcy and DN.

METHODS

A Mendelian randomization (MR) study using data from 2 samples was employed to infer causal relationships. The aggregated genetic data associated with Hcy was derived from the largest genome-wide association study (GWAS) to date, involving 44,147 individuals of European ancestry.Data on SNP-diabetic nephropathy, creatinine, and urea nitrogen were obtained from the IEU GWAS database. The analysis method employed a fixed-effect or random-effect inverse variance-weighted approach to estimate effects.Additional analysis methods were used to assess stability and sensitivity. The potential for pleiotropy was evaluated using the MR-Egger intercept test.

RESULTS

Using 12 SNPs as instrumental variables, two-sample MR analysis revealed no evidence of a causal relationship between genetically predicted plasma Hcy levels and diabetic nephropathy, as well as creatinine and blood urea nitrogen levels. This finding is consistent with the results obtained from other testing methods.

CONCLUSIONS

Two-sample Mendelian Randomization analysis found no evidence of a causal relationship between plasma homocysteine levels and diabetic nephropathy, creatinine, or urea.

Genetic information supports a causal relationship between trace elements, inflammatory proteins, and COPD: evidence from a Mendelian randomization analysis

Objective

Dietary factors and nutritional status may be among the risk factors for Chronic Obstructive Pulmonary Disease (COPD). There exists a certain correlation between trace elements and COPD. Through Mendelian Randomization (MR) analysis, we investigated the causal relationships between trace elements, inflammatory proteins, and COPD.

Methods

We employed MR, multivariable MR (MVMR), and two-step MR (TSMR) approaches to assess the causal links between 15 trace elements and COPD, with 91 inflammatory proteins serving as mediators to further elucidate the tripartite causal relationships.

Results

Trace elements such as Folate (OR = 1.293, 95%CI 1.027-1.628; p = 0.029), Vitamin D (OR = 1.331, 95%CI 1.071-1.654; p = 0.010), Vitamin B12 (OR = 1.424, 95%CI 1.108-1.828; p = 0.006), and Iron (OR = 0.741, 95%CI 0.580-0.946; p = 0.016) demonstrated causal relationships with COPD. No causal relationship was observed in reverse MR. After adjusting for BMI, Folate (OR = 1.633, 95%CI 1.098-2.429; p = 0.015), Iron (OR = 0.507, 95%CI 0.31-0.778; p = 0.001), and Vitamin D (OR = 1.511, 95%CI 1.029-2.217; p = 0.034) were identified as independent risk factors for COPD, whereas Vitamin B12 (OR = 1.118, 95%CI 0.751-1.666; p = 0.581) was not. Mediation analysis indicated that CDCP1 (5.76%) may play a mediating role between Iron and COPD.

Conclusion

Trace elements such as Folate, Vitamin D, Vitamin B12, and Iron have causal relationships with COPD. After BMI adjustment, Folate, Vitamin D, and Iron emerge as independent risk factors. Furthermore, the inflammatory protein CDCP1 may partially mediate the causal relationship between Iron and COPD, offering a scientific basis for dietary recommendations that could benefit COPD patients. The supplementation of trace elements may be advantageous for individuals suffering from COPD.

[Shenqi Chongcao Formula ameliorates inflammatory response in rats with pulmonary fibrosis by activating the ASS1/src/STAT3 signaling pathway]

OBJECTIVE

To observe the effect of Shenqi Chongcao (SQCC) Formula on the ASS1/src/STAT3 signaling pathway in a rat model of lung fibrosis and explore its therapeutic mechanism.

METHODS

A total of 120 male SD rats were divided equally into 5 groups, including a blank control group with saline treatment and 4 groups of rat models of idiopathic pulmonary fibrosis induced by intratracheal instillation of bleomycin. One day after modeling, the rat models were treated with daily gavage of 10 mL/kg saline, SQCC decoction (0.423 g/kg), pirfenidone (10 mL/kg), or intraperitoneal injection of arginine deiminase (ADI; 2.25 mg/kg, every 3 days) for 28 days. After the treatments, the lung tissues of the rats were collected for calculating the lung/body weight ratio, observing histopathology using HE and Masson staining, and analyzing the inflammatory cells in BALF using Giemsa staining. Serum chemokine ligand 2 (CCL2) and transforming growth factor-β1 (TGF-β1) levels were measured with ELISA. The protein expressions of src, p-srcTry529, STAT3, and p-STAT3Try705 and the mRNA expressions of ASS1, src and STAT3 in the lung tissues were detected using Western blotting and RT-qPCR.

RESULTS

The neutrophil, macrophage and lymphocyte counts and serum levels of CCL2 and TGF-β1 were significantly lower in SQCC, pirfenidone and ADI treatment groups than in the model group at each time point of measurement (P < 0.05). P-srcTry529 and p-STAT3Try705 protein expression levels and ASS1, src, and STAT3 mRNA in the lung tissues were also significantly lower in the 3 treatment groups than in the model group (P < 0.05).

CONCLUSION

SQCC Formula can alleviate lung fibrosis in rats possibly by activating the ASS1/src/STAT3 signaling pathway in the lung tissues.

Targeting type I PRMTs as promising targets for the treatment of pulmonary disorders: Asthma, COPD, lung cancer, PF, and PH

Pulmonary disorders, including asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis (PF), pulmonary hypertension (PH), and lung cancer, seriously impair the quality of lives of patients. A deeper understanding of the occurrence and development of the above diseases may inspire new strategies to remedy the scarcity of treatments. Type I protein arginine methyltransferases (PRMTs) can affect processes of inflammation, airway remodeling, fibroblast proliferation, mitochondrial mass, and epithelial dysfunction through substrate methylation and non-enzymatic activity, thus affecting the occurrence and development of asthma, COPD, lung cancer, PF, and PH. As potential therapeutic targets, inhibitors of type I PRMTs are developed, moreover, representative compounds such as GSK3368715 and MS023 have also been used for early research. Here, we collated structures of type I PRMTs inhibitors and compared their activity. Finally, we highlighted the physiological and pathological associations of type I PRMTs with asthma, COPD, lung cancer, PF, and PH. The developing of type I PRMTs modulators will be beneficial for the treatment of these diseases.