Effect of low intensity ultra sound on bone regeneration and healing: a systematic review

ABSTRACT Objective: Low Intensity Pulsed Ultra Sound (LIPUS) is found to have stimulatory effect on bone healing and regeneration. This review aimed to assess whether LIPUS enhances bone regeneration and healing in terms of efficiency in improving clinical, radiographic, histologic parameters or serum and tissue biomarkers. Methods: A comprehensive search based on PRISMA guidelines with pre-determined eligibility criteria was conducted to identify randomized controlled clinical trials evaluating effectiveness of Low intensity pulsed ultrasound in bone regeneration and healing. The title and abstract of the entries in all languages yielded from the PubMed, Google scholar and Cochrane library were screened. Results: 14 eligible Randomized controlled trials testing the effectiveness of LIPUS was evaluated. More heterogeneity was seen in the screened studies with respect to sample characteristics, type of bone and outcome measures. The studies that screened histological parameters state that LIPUS is significantly beneficial than control. In terms of time for radiographic union, most of the studies stated that LIPUS was more effective than control but numberof studies are very few. Whereas studies which evaluated parameters such as healing time and radiographic union were showing highly inconsistent results regarding effectiveness of LIPUS. Conclusion: This review cannot give a definitive conclusion that LIPUS is effective in bone healing with respect to clinical parameters but a positive influence on radiographical and histological parameters in bone healing and regeneration is promising to pursue future research.

Low-intensity pulsed ultrasound ameliorates angiotensin II-induced cardiac fibrosis by alleviating inflammation via a caveolin-1-dependent pathway / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

OBJECTIVES@#Cardiac hypertrophy and fibrosis are major pathological manifestations observed in left ventricular remodeling induced by angiotensin II (AngII). Low-intensity pulsed ultrasound (LIPUS) has been reported to ameliorate cardiac dysfunction and myocardial fibrosis in myocardial infarction (MI) through mechano-transduction and its downstream pathways. In this study, we aimed to investigate whether LIPUS could exert a protective effect by ameliorating AngII-induced cardiac hypertrophy and fibrosis and if so, to further elucidate the underlying molecular mechanisms.@*METHODS@#We used AngII to mimic animal and cell culture models of cardiac hypertrophy and fibrosis. LIPUS irradiation was applied in vivo for 20 min every 2 d from one week before mini-pump implantation to four weeks after mini-pump implantation, and in vitro for 20 min on each of two occasions 6 h apart. Cardiac hypertrophy and fibrosis levels were then evaluated by echocardiographic, histopathological, and molecular biological methods.@*RESULTS@#Our results showed that LIPUS could ameliorate left ventricular remodeling in vivo and cardiac fibrosis in vitro by reducing AngII-induced release of inflammatory cytokines, but the protective effects on cardiac hypertrophy were limited in vitro. Given that LIPUS increased the expression of caveolin-1 in response to mechanical stimulation, we inhibited caveolin-1 activity with pyrazolopyrimidine 2 (pp2) in vivo and in vitro. LIPUS-induced downregulation of inflammation was reversed and the anti-fibrotic effects of LIPUS were absent.@*CONCLUSIONS@#These results indicated that LIPUS could ameliorate AngII-induced cardiac fibrosis by alleviating inflammation via a caveolin-1-dependent pathway, providing new insights for the development of novel therapeutic apparatus in clinical practice.

The effects of low intensity pulsed ultrasound on the expression of calcium transportation associated proteins during dentin-pulp complex injury and repair in rats / 实用口腔医学杂志

Objective: To investigate low intensity pulsed ultrasound (LIPUS) on the expression of L-type calcium ion channels(cav1. 2) and Na +-Ca2 + exchangers(NCX1) during dentin-pulp complex injury and repair in rats. Methods: Cavity preparation was made on the upper right first molar of 40 male adult SD rats,20 of them and the upper left first molar of the other 20 were randomly chosen for LIPUS irradiation(frequency: 1. 5 MHz,200 μs pulses,pulse repetition frequency: 1 KHz,ISATA 30 mW/cm2,20 min /d),so the animals were randomly allocated into 4 groups(n = 10): Control group,LIPUS group,cavity preparation group and cavity preparation + LIPUS group. At 1,3,7,14 d post-irradiation the rats were sacrificed respectively for HE stain and immunohistochemical analysis. Results: Reparative dentin formation was observed at 14 days after cavity preparation and LIPUS irradiation,the expression of Cav1. 2(L-type) and NCX1 in this group were increased significantly at day 1 and day 3. Compared with the control group, the expression of Cav1. 2 in LIPUS group increased at day 1 post-irradiation. Conclusion: LIPUS may enhance tertiary dentin formation and up-regulate the expression of Cav1. 2 and NCX1 at the early period of dentin injury.

The effects of low intensity pulsed ultrasound on the osteogenetic differentiation of BMSCs on titanium with different surface topography / 实用口腔医学杂志

Objective:To observe the effects of low intensity pulsed ultrasound(LIPUS) on the osteogenic differentiation of rat bone marrow mesenchymal stem cells(BMSCs) on titanium surface.Methods:BMSCs from Wistar rat bone marrow were respectively cultured on the flat titanium surface and the large grain blast acid etched(SLA) titanium surface,and induced by mineralization medium.Then,the cells were interfered by LIPUS and a control condition.Alkaline phosphatase(ALP) were quantitative determinated after 3 and 7 d mineralization induction respectively,ALP staining were observed after 14 d induction.Alizarin red staining were observed after 21 d mineralization induction.Osteogenic related protein and gene expressions were detected after mineralization induction.Results:ALP in culture medium of LIPUS group was higher than that of the control group after 3 d and 7 d mineralization induction(P＜0.05).LIPUS group showed stronger ALP staining and alizarin staining,and more mineralized nodules than control group.The expression of osteogenic related proteins,including Runx2,BMP2,OPN in LIPUS group increased.Osteogenic related genes expression,including ALP,Runx2,BMP2,OPN,OCN and Col-1 of the LIPUS group increased.Conclusion:The osteogenic differentiation of BMSCs on the fiat titanium surface or SLA titanium surface can be promoted by LIPUS.

Effect of low intensity pulsed ultrasound on repairing the periodontal bone of Beagle canines

OBJECTIVE@#To investigate the repairing effect of low intensity pulsed ultrasound (LIPUS) on the Beagle canines periodontal bone defect.@*METHODS@#A total of 12 Beagle dogs with periodontal bone defect model were randomly divided into control group, LIPUS group, guided tissue regeneration (GTR) group and LIPUS+GTR group, with three in each. After completion of the models, no other proceeding was performed in control group; LIPUS group adopt direct exposure to radiation line LIPUS processing 1 week after modeling; GTR group adopted treatment with GTR, following the CTR standard operation reference; LIPUS+GTR group was treated with LIPUS joint GTR. Temperature change before treatment and histopathological change of periodontal tissue after repair was observed.@*RESULTS@#There was no significant difference in temperature changes of periodontal tissue between groups (P>0.05). The amount and maturity of LIPUS+GTR group were superior to other groups; new cementum, dental periodontal bones of GTR group were superior to the control group but less than LIPUS group; new collagen and maturity of the control group is not high relatively.@*CONCLUSIONS@#LIPUS can accelerate the calcium salt deposition and new bone maturation, thus it can serve as promoting periodontal tissue repair, and shortening the periodontal tissue repair time.

Possible molecular mechanism of promotion of repair of acute achilles tendon rupture by low intensity-pulsed ultrasound treatment in a rat model / Posible mecanismo molecular de promoción de la ruptura aguda del tendón de aquiles por el tratamiento de ultrasonidos pulsados de baja intensidad en un modelo de rata

OBJECTIVE: This study investigated the effect of Low Intensity-pulsed Ultrasound (LIPUS) on the repair process of ruptured Achilles tendon using a rat model and also examined the regulation of a biological molecule that may contribute to this in vitro and in vitro. METHODS: To investigate the effect of LIPUS and its biological mechanism ofpromoting Achilles tendon repair after acute injury, ninety-eight male Sprague-Dawley (SD) rats (mean body weight, 258 ±9.8 g) aged 12 weeks were used in this study. To create the model, the Achilles tendon attachment site and musculotendinous junction were ruptured under direct vision. The leg on one side was exposed to LIPUS (frequency at 1.5 MHz, the repetition cycle at 1.0 kHz, the burst width at 200 msec and the power output at 45 mW/cm2), for 20 minutes daily with a 0.7 mm diameter probe. Results:Low Intensity-pulsed Ultrasound treatment accelerated the repair of the Achilles tendon compared to the untreated group, judged by electron microscopy. Both cyclo-oxygenase (COX)-2* and EP4* expressions were over-expressed in the LIPUS treated group in the inflammatory period, and TGFJ31* expression was markedly induced in LIPUS treated groups followed by collagen I* and III* expression in the repair and reconstitution process. CONCLUSION: These findings suggest that LIPUS is potentially able to accelerate the repair of acute ruptured Achilles tendon in several ways: by exaggerating inflammation by inducing COX-2 and EP4 and reconstituting tissue by inducing TGFJ31 followed by collagen I and III. (*: p < 0.05, **: 0.001).

OBJETIVO: Este estudio estuvo encaminado a investigar el efecto de los ultrasonidos pulsados de baja intensidad (LIPUS) sobre el proceso de reparación del tendón de Aquiles tras una ruptura, usando un modelo de rata. Asimismo, se examinó la regulación de una molécula biológica que puede contribuir a este proceso in vitro e in vitro. MÉTODOS: Con el fin de investigar el efecto de LIPUS y el mecanismo biológico por el cual este efecto promueve la reparación del tendón de Aquiles tras una lesión aguda, noventa y ocho ratas machos Sprague-Dawley (SD) (peso corporal promedio, 258 ± 9.8 g) de 12 semanas de edad fueron usadas en este estudio. Para crear el modelo, el sitio de ligazón microbiológica del tendón de Aquiles y la unión músculo-tendinosa fueron desgarrados bajo visión directa. La pierna de un lado fue expuesta a LIPUS (frecuencia de 1.5 MHz, ciclo de repetición de 1.0 kHz, ancho de ruptura de 200 msec, y potencia de salida de 45 mW/cm2), por 20 minutos diariamente con una sonda de 0.7 mm diámetro. RESULTADOS: El tratamiento de ultrasonidos pulsados de baja intensidad aceleró la reparación del tendón de Aquiles, en comparación con el grupo no tratado, según se apreció mediante el microscopio electrónico. Tanto la ciclo-oxygenasa (COX)-2* como las expresiones EP4* estuvieron sobe-expresadas en el grupo tratado con LIPUS en el periodo inflamatorio, y la expresión TGFfi1* fue marcadamente inducida en los grupos tratados con LIPUS seguidos por la expresión de colágeno I* y III* en el proceso de reparación y reconstitución. CONCLUSIÓN: Estos resultados sugieren que LIPUS puede potencialmente acelerar la reparación del tendón de Aquiles luego de un desgarramiento, de varias maneras: exagerando la inflamación mediante inducción de COX-2 y EP4 y reconstituyendo el tejido induciendo TGFfil seguido por colágeno I y III. (*: p < 0.05, **: 0.001).

Effect of Low Intensity Pulsed Ultrasound with Adipose-Derived Stem Cells on Bone Healing around a Titanium Implant in Tibia of Osteoporosis-Induced Rats