Pulmonary hypertension(PH)is a serious cardiovascular condition that significantly impacts pa-tients'quality of life.Currently available clinical medications lack selectivity for pulmonary blood vessels,often produce substantial side effects,and are prohibitively expensive.Therefore,it is crucial to explore the mechanisms underlying the onset and progression of PH and to develop new,effective treatments.Ubiquitination is a key form of protein post-transla-tional modification in which specific E3 enzymes recognize substrate proteins and induce ubiquitination,leading to chang-es in their activity or stability.During the onset of PH,the activities of ubiquitin ligases and deubiquitinases undergo vari-ous changes,resulting in altered ubiquitination levels of different proteins.These variations primarily influence the degra-dation rates of substrate proteins within cells,thereby regulating essential physiological processes.Proteasomes play a vi-tal role in the degradation of ubiquitinated proteins,and inhibitors targeting these complexes have been developed,demon-strating therapeutic efficacy in experimental settings of PH.However,their low specificity presents significant challenges for practical applications.In this context,we summarize the relevant mechanisms of ubiquitination regulation in the onset of PH and highlight its practical significance for future therapeutic strategies.

Pulmonary hypertension(PH)is a serious cardiovascular condition that significantly impacts pa-tients'quality of life.Currently available clinical medications lack selectivity for pulmonary blood vessels,often produce substantial side effects,and are prohibitively expensive.Therefore,it is crucial to explore the mechanisms underlying the onset and progression of PH and to develop new,effective treatments.Ubiquitination is a key form of protein post-transla-tional modification in which specific E3 enzymes recognize substrate proteins and induce ubiquitination,leading to chang-es in their activity or stability.During the onset of PH,the activities of ubiquitin ligases and deubiquitinases undergo vari-ous changes,resulting in altered ubiquitination levels of different proteins.These variations primarily influence the degra-dation rates of substrate proteins within cells,thereby regulating essential physiological processes.Proteasomes play a vi-tal role in the degradation of ubiquitinated proteins,and inhibitors targeting these complexes have been developed,demon-strating therapeutic efficacy in experimental settings of PH.However,their low specificity presents significant challenges for practical applications.In this context,we summarize the relevant mechanisms of ubiquitination regulation in the onset of PH and highlight its practical significance for future therapeutic strategies.

Objective To elucidate the causal relationship between high-density lipoprotein cholesterol(HDL-C)and colorectal cancer(CRC)through Mendelian randomization.Methods Mendelian randomi-zation analysis was conducted using genetic instrumental variables selected from a genome-wide association study dataset.The main methods included inverse variance weighted,MR-Egger,weighted median,simple mode,and weighted mode method;among which,inverse variance weighted method served as the primary analytical approach.Sensitivity analyses were performed to verify the robustness of results.Results A total of 41 genetic instrumental variables associated with HDL-C were identified.Inverse variance weighted method(OR=0.84,95% CI:0.73-0.96,P=0.01)and weighted median method(OR=0.82,95% CI:0.67-0.99,P=0.04)indicated a negative correlation between genetically-determined HDL-C and CRC risk.Sensitivity analyses confirmed the absence of heterogeneity and horizontal pleiotropy(P>0.05).Conclusion A causal relationship exists between HDL-C and CRC risk,with rs1077834 as a potential key determinant in the influence of HDL-C on CRC risk.

Objective To investigate the ameliorative effects and potential mechanism of Lithocarpus litseifoliu on renal function and inflammation in mice with hyperuricemic nephropathy(HN).Methods The HN model was established by the combined administration of adenine and potassium oxyzate.The mice were randomly divided into normal control group,model control group,benzbromarone group,and high,medium and low dose groups of Lithocarpus litseifoliu.Different drugs were given to the mice,and their body mass was recorded once a week.The levels of uric acid(UA),creatinine(Cr),urine protein(UP),blood urea nitrogen(BUN)and urine urea nitrogen(UUN)as well as the levels of tumor necrosis factor α(TNF-α)and interleukin 6(IL-6)in serum or urine of each group were collected and measured on the 21st day.Hematoxylin-eosin(HE)staining was performed to observe kidney tissue injury in mice;real-time PCR(RT-PCR)was performed to determine ATP-binding cassette subfamily G member 2(ABCG2),urate transporter protein(URAT1),glucose transporter protein 9(GLUT9),and cytosolic factor NF-κB p50(κB p50)in kidney tissues.Results Compared with the normal control group,the body mass of mice in the model control group was significantly lower after the second weeks of modeling(P＜0.05),and the levels of UA,Cr,UP,BUN,UUN,TNF-α,IL-6 contents and GLUT9 mRNA and κB p50 mRNA expression contents of kidney tissues were significantly higher(P＜0.01,P＜0.05).Compared with the model control group,the levels of Cr,UP,BUN and UUN contents and renal tissue nuclear cytokine κB p50 mRNA expression were significantly lower in the high,medium and low dose groups of Lithocarpus litseifoliu(P＜0.01,P＜0.05).The UA levels were significantly lower in the high dose group of Lithocarpus litseifoliu(P＜0.05),and renal ABCG2 mRNA expression was significantly higher in the medium dose group(P＜0.01).The renal URAT1 mRNA expression was significantly decreased in the low dose group(P＜0.01).Conclusion Lithocarpus litseifoliu has shown ameliorative effects on HN mice,and the mechanism may be related to the modulation of renal uric acid transporters,improvement of renal function and anti-inflammation effects.