Growth plate,the developmental center of endochondral osteogenesis,can be divided morphologically and functionally into a resting zone,a proliferative zone,a prehypertrophic zone and a hypertrophic zone.Injuries to growth plate often lead to bone growth defects including limb length discrepancy and angulation deformity in children.Currently,their orthopedic corrective surgeries are invasive and limitedly effective and no effective biotherapy has been available.Previous studies on animal models of growth plate damage have investigated the related cellular and molecular events in the repair of damaged growth plates in the 4 distinct inflammatory,fibrogenic,osteogenic and remodeling phases.Related molecules involved in the regulation of the above processes,such as inflammatory cytokines tumor necrosis factor alpha,mitogenic platelet-derived growth factor and bone morphogenetic protein,are found to participate in the regulation of growth plate injury.Exploration of the mechanisms may provide new targets for biotherapy.In addition,development of cartilage tissue engineering,especially application of mesenchymal stem cells,also provides potential interventions for growth plate injury.

Objective To investigate the effect and mechanism of Feixin Decoction(Astragali Radix,Pericae Semen,Carthami Flos,Descurainiae Semen Lepidii Semen,Paeoniae Radix Rubra,etc.)on monocrotaline-induced pulmonary arterial hypertension(PAH)rats based on peroxisome proliferator-activated receptor-γ/nuclear factor-κB(PPAR-γ/NF-κB)signaling pathway.Methods Forty-eight male SD rats were randomly divided into normal group,model group,Sildenafil group(0.025 g·kg-1)and low-,medium-and high-dose of Feixin Decoction groups(11.7,23.4,46.8 g·kg-1).PAH rat model was established by single intraperitoneal injection of monocrotaline solution(60 mg·kg-1).After 1 hour of modeling,the rats were given intragastric administration once a day for 28 days.Hemodynamic and echocardiographic parameters including right ventricular systolic pressure(RVSP),mean pulmonary artery pressure(mPAP),right ventricular hypertrophy index(RVHI),pulmonary artery acceleration time(PAAT),pulmonary artery ejection time(PET),tricuspid annular plane systolic excursion(TAPSE),right ventricular internal diameter(RVIDd)and right ventricular anterior wall thickness(RVAWT)were measured in each group.The pathological changes of pulmonary arterioles were observed by HE staining.The expression level of α-smooth muscle actin(α-SMA)in rat pulmonary artery was detected by immunofluorescence.The levels of plasma interleukin-1β(IL-1β),IL-6 and tumor necrosis factor-α(TNF-α)were detected by ELISA.The expression levels of PPAR-γ/NF-κB signaling pathway-related proteins were detected by immunohistochemistry and Western Blot.Results Compared with the normal group,the RVSP,mPAP,RVHI,RVIDd and RVAWT of the model group were significantly increased(P＜0.01).PAAT,PAAT/PET and TAPSE were significantly decreased(P＜0.01).The wall of pulmonary arterioles was significantly thickened,and the percentage of wall thickness of pulmonary arterioles to vascular diameter and the percentage of vascular wall area to total cross-sectional area of pulmonary arterioles were significantly increased(P＜0.01).The positive expression rate of α-SMA protein in pulmonary artery was significantly increased(P＜0.01).The levels of plasma IL-1β,IL-6 and TNF-α were significantly increased(P＜0.01).The positive expression rate of PPAR-γ protein in lung tissue was significantly decreased(P＜0.01),and the positive expression rate of NF-κB protein was significantly increased(P＜0.01).The protein expressions of PPAR-γ and IκB-α in lung tissue were significantly down-regulated(P＜0.01).The protein expression ratio of p-NF-κB/NF-κB was significantly increased(P＜0.01).Compared with the model group,RVSP,mPAP,RVHI,RVIDd and RVAWT in each administration group were significantly decreased(P＜0.05,P＜0.01),while PAAT,PAAT/PET and TAPSE were significantly increased(P＜0.05,P＜0.01).The thickness of the vascular wall was significantly reduced,and the percentage of the wall thickness of the pulmonary arterioles to the diameter of the blood vessels and the percentage of the vascular wall area to the total cross-sectional area of the small arteries were significantly reduced(P＜0.05,P＜0.01).The positive expression rate of α-SMA protein in pulmonary artery was significantly decreased(P＜0.05,P＜0.01).The plasma levels of IL-1β,IL-6 and TNF-α were significantly decreased(P＜0.05,P＜0.01).The positive expression rate of PPAR-γ protein in lung tissue was significantly increased(P＜0.05,P＜0.01),and the positive expression rate of NF-κB protein was significantly decreased(P＜0.05,P＜0.01).The protein expression of PPAR-γ in lung tissue was significantly up-regulated(P＜0.05,P＜0.01),and the protein expression ratio of p-NF-κB/NF-κB was significantly decreased(P＜0.01).The protein expression of IκB-α in the lung tissue of rats in the high-dose group of Feixin Decoction was significantly up-regulated(P＜0.01).Conclusion Feixin Decoction can improve pulmonary artery pressure,right ventricular dysfunction and pulmonary vascular remodeling in PAH rats induced by monocrotaline.The mechanism may be related to the regulation of PPAR-γ/NF-κB signaling pathway to inhibit inflammatory response.

Objective To monitor heart-related parameters of hypoxic pulmonary hypertension(PH)mouse models induced by hypoxia alone and hypoxia combined with vascular endothelial growth factor receptor inhibitor SU5416 using echocardiography,and to construct the prediction equation of right ventricular systolic pressure(RVSP).Twenty-four C57BL/6J male mice were randomly divided into simple hypoxia group(group A),hypoxia combined with SU5416 group(group B),control group(group C),each group 8 mice.Hypoxic PH models were constructed with hypoxia alone and hypoxia combined with SU5416 in group A and group B,respectively.Echocardiography was performed before and during modeling(2,3,4 weeks after interventions),and the relevant parameters were obtained.RVSP was measured using right heart catheterization after the last echocardiography.The changes of ultrasonic parameters were observed,the correlations of ultrasonic parameters 4 weeks after intervention with RVSP were observed,and linear equations for predicting RVSP were established.Results With time going,during modeling,pulmonary artery diameter(PAD),PAD/aorta diameter(AOD)and right ventricle anterior wall thickness(RVAWT)increased,while heart rate,pulmonary artery acceleration time(PAAT),PAAT/pulmonary artery ejection time(PAET)and tricuspid annular plane systolic excursion(TAPSE)decreased in group A and B(all P＜0.05).Three and 4 weeks after interventions,PAET,PAAT/PAET and TAPSE in group B decreased compared with those in group A(all P＜0.05).Four weeks after interventions,RVSP in group A and B were highly correlated with PAD/AOD,RVAWT,PAAT,PAAT/PAET and TAPSE(all P＜0.05).The linear regression equations of PAAT/PAET and TAPSE for predicting RVSP in simple hypoxic PH mice models included RVSP=-161.7 ×(PAAT/PAET)+63.85,as well as RVSP=-36.53 ×TAPSE+71.55,while of predicting RVSP in hypoxia combined with VEGFR-2 inhibitor PH mouse models were as follows:RVSP=-266.4 ×(PAAT/PAET)+91.59,RVSP=-69.14 × TAPSE+116.5.Conclusion Four weeks after inerventions,the phenotypes of hypoxic PH mouse models induced by hypoxia alone and hypoxia combined with SU5416 became obvious.Prediction equations of RVSP established based on PAAT/PAET and TAPSE obtained with echocardiography could provide references for relevant research.

Pulmonary hypertension(PH)is a progressive pulmonary vascular disease that can lead to right heart failure and death.In recent years,the incidence of PH has been increasing year by year and there is a lack of effective treatment.TCM can play an important synergistic role in the treatment of PH.Pulmonary vascular remodeling is a core pathological feature of PH,which is closely related to the physiological structure and pathological changes of the collaterals.Based on the collateral disease theory,this article described the key pathogenesis of PH in TCM and Western medicine,including the lesions of the pulmonary and cardiovascular complexes and pulmonary vascular remodeling,analyzed the physiology of the"collateral-vessel"in PH,sorting out the pathological correlation,and explored TCM targeting pulmonary vascular remodeling in the identification and treatment of PH,so as to provide a new way of thinking for the clinical treatment of PH.

ObjectiveTo investigate the mechanism by which Feixin decoction treats hypoxic pulmonary hypertension （HPH） by regulating the peroxisome proliferator-activated receptor gamma （PPARγ）/nuclear factor-kappa B （NF-κB）/NOD-like receptor pyrin domain containing 3 （NLRP3） signaling pathway. MethodsForty-eight male SD rats were randomly allocated into normal， hypoxia， and low-， medium- and high-dose （5.85， 11.7， 23.4 g·kg^-1， respectively） Feixin decoction groups， with 8 rats in each group. Except the normal group， the remaining five groups were placed in a hypoxia chamber with an oxygen concentration of （10.0±0.5）% for 8 h per day， 28 days， and administrated with corresponding drugs during the modeling process. After 4 weeks of treatment， echocardiographic parameters ［pulmonary artery acceleration time （PAT）， pulmonary artery ejection time （PET）， right ventricular anterior wall thickness （RVAWd）， and tricuspid annular plane systolic excursion （TAPSE）］ were measured for each group. The right ventricular systolic pressure （RVSP） was measured by the right heart catheterization method， and the right ventricular hypertrophy index （RVHI） was calculated by weighing the heart. The pathological changes in pulmonary arterioles were observed by hematoxylin-eosin staining. The co-localization of α-smooth muscle actin （α-SMA） with NLRP3， N-terminal gasdermin D （N-GSDMD）， and cysteinyl aspartate-specific proteinase-1 （Caspase-1） in pulmonary arteries was detected by immunofluorescence. The protein levels of PPARγ， NF-κB， NLRP3， apoptosis-associated speck-like protein containing a CARD （ASC）， N-GSDMD， interleukin-1β （IL-1β）， interleukin-18（IL-18）， and cleaved Caspase-1 in the lung tissue was determined by Western blot. The ultrastructural changes in pulmonary artery smooth muscle cells （PASMCs） were observed by transmission electron microscopy. ResultsCompared with the normal group， the hypoxia group showed increased RVSP and RVHI （P<0.01）， decreased right heart function （P<0.01）， increased pulmonary vascular remodeling （P<0.01）， increased co-localization of α-SMA with NLRP3， N-GSDMD， and Caspase-1 in pulmonary arterioles （P<0.01）， up-regulated protein levels of NF-κB， NLRP3， ASC， N-GSDMD， IL-1β， IL-18， and cleaved Caspase-1 in the lung tissue （P<0.05， P<0.01）， a down-regulated protein level of PPARγ （P<0.05， P<0.01）， and pyroptosis in PASMCs. Compared with the hypoxia group， Feixin decoction reduced RVSP and RVHI， improved the right heart function and ameliorated pulmonary vascular remodeling （P<0.05， P<0.01）， decreased the co-localization of α-SMA with NLRP3， N-GSDMD， and Caspase-1 （P<0.05， P<0.01）， down-regulated the protein levels of NF-κB， NLRP3， ASC， N-GSDMD， IL-1β， IL-18， and cleaved Caspase-1 in the lung tissue （P<0.05， P<0.01）， up-regulated the protein level of PPARγ （P<0.05， P<0.01）， and alleviated pyroptosis in PASMCs. ConclusionFeixin decoction can ameliorate pulmonary vascular remodeling and right heart dysfunction in chronically induced HPH rats by regulating pyroptosis in PASMCs through the PPARγ/NF-κB/NLRP3 pathway.