Low-intensity Pulsed Ultrasound Group Research Articles

Effects of low-intensity pulsed ultrasound on knee osteoarthritis: A systematic review and meta-analysis of randomized controlled trials

Objective To systemically review the effects of low-intensity pulsed ultrasound (LIPUS) on pain relief and functional recovery in patients with knee osteoarthritis (KOA). Data sources PubMed, Web of Science, Cochrane Library, Physiotherapy Evidence Database (PEDro), and China National Knowledge Infrastructure (CNKI) were used from inception to 18 March 2022. Review Methods Meta-analysis was performed to evaluate pain and function recovery between control and LIPUS groups. Standardized mean difference (SMD) or mean difference (MD) and 95% confidence interval (CI) were calculated, and data were combined using the fixed or random-effect model. Results Thirteen studies involving 807 patients with KOA were included. Patients’ outcomes treated by LIPUS were improved significantly, including Visual analog scale (VAS) score (MD = −0.95, 95% CI: −1.43 to −0.48，P < 0.001), Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) score (MD = −4.35, 95% CI: −8.30 to −0.40, P = 0.0309), Lysholm score (SMD = 1.59, 95% CI: 1.29 to 1.90, P < 0.001), Lequesne index (MD = −1.33, 95% CI: −1.69 to −0.96, P < 0.001), Range of motion (ROM) (MD = 2.43, 95% CI: 0.39 to 4.46, P = 0.0197) and 50 meter walking time (SMD = 1.48, 95% CI: 0.46 to 2.49, P = 0.0044). Subgroup analyses showed monotherapy of LIPUS produced a better effect on reducing VAS score (P = 0.0213), and the shorter therapeutic period (≤4 weeks) produced a more significant effect on raising the WOMAC score (P = 0.0083). Conclusion LIPUS was beneficial for pain relief and functional knee recovery and maybe as an alternative therapy in KOA rehabilitation.

Effect of Low-Intensity Pulsed Ultrasound (LIPUS) on Alveolar Bone during Maxillary Expansion Using Clear Aligners.

The present study evaluated the possible effect of low-intensity pulsed ultrasound (LIPUS) on buccal bone plate thickness and height after maxillary arch expansion using clear aligners. The cone beam computed tomography (CBCT) of before and immediately after maxillary arch expansion (3 mm per side) of 28 adult patients (18 in LIPUS group and 10 in control) (average age 36.2 ± 13.2 years old) was analyzed. The wearing protocol of clear aligners in the LIPUS group was to change the aligners every 4 to 5 days, while the wearing protocol in the control group (without LIPUS) was to change the aligners every 7 to 10 days. Bone thickness at 3 mm and 6 mm from the buccal alveolar bone crests, along with the measurements of buccal alveolar bone heights, was measured in standardized sagittal sections. Data were analyzed through paired sample t-test and the Wilcoxon test. The results were given as mean ± standard deviation and 95% confidence intervals. p value < 0.05 was considered statistically significant. The results showed significant increase in bone height in both groups. However, comparison of both LIPUS and control groups showed no statistically significant difference in bone thickness or bone height. The results of this study showed that the use of LIPUS together with accelerated aligner tray change protocol did not affect alveolar bone integrity when compared to the control group.

Non-Invasive Local Acoustic Therapy Ameliorates Diabetic Heart Fibrosis by Suppressing ACE-Mediated Oxidative Stress and Inflammation in Cardiac Fibroblasts.

The extent of myocardial fibrosis is closely related to the prognosis of diabetic cardiomyopathy (DCM). Low-intensity pulsed ultrasound (LIPUS) has been reported to have multiple biological effects. However, the effect of LIPUS on diabetic heart fibrosis remains unclear. The present study aimed to investigate the effect of LIPUS on diabetic heart fibrosis and explore its underlying mechanisms. High glucose (HG) was applied to cultured neonatal rat cardiac fibroblasts (NRCFs) to mimic the in vivo hyperglycemia microenvironment. LIPUS (19.30mW/cm2 to 77.20mW/cm2) dose-dependently inhibited HG-induced fibrotic response in NRCFs. Also, LIPUS downregulated NADPH oxidase 4 (NOX4)-associated oxidative stress and nod-like receptor protein-3 (NLRP3) inflammasome activation in NRCFs. In vivo, diabetes in mice was induced with streptozotocin (STZ). Mice in the LIPUS group and STZ + LIPUS group were treated with LIPUS (77.20mW/cm2) twice a week for 12weeks and then euthanized at 12weeks or 24weeks post-diabetes. Treatment with LIPUS significantly ameliorated the progression of cardiac fibrosis (Masson staining 6.5 ± 2.3% vs. 2.8 ± 1.5%, P< 0.001) and dysfunction (E/A ratio 1.35 ± 0.14 vs. 1.59 ± 0.11, P< 0.05), as well as NOX4-associated oxidative stress (relative expression fold of NOX4 1.43 ± 0.12 vs. 1.07 ± 0.10, P< 0.01; relative DHE fluorescence 1.51 ± 0.13 vs. 1.28 ± 0.06, P< 0.05) and NLRP3 inflammasome activation (relative expression fold of NLRP3 1.57 ± 0.12 vs. 1.05 ± 0.16, P< 0.01), at 12weeks post-diabetes. At 24weeks post-diabetes, the heart function in diabetic mice treated with LIPUS was still significantly better than untreated diabetic mice (E/A ratio 1.08 ± 0.12 vs. 1.49 ± 0.14, P< 0.001). Further exploration revealed that LIPUS significantly attenuated the upregulated angiotensin-converting enzyme (ACE) and angiotensin II (AngII), in both HG-induced NRCFs and diabetic hearts (relative expression of ACE in myocardium 3.77 ± 0.55 vs. 1.07 ± 0.13, P< 0.001; AngII in myocardium 115.5 ± 21.77ng/ml vs. 84.28 ± 9.03ng/ml, P< 0.01). Captopril, an ACE inhibitor, inhibited NOX4-associated oxidative stress and NLRP3 inflammasome activation in both HG-induced NRCFs and diabetic hearts. Our results indicate that non-invasive local LIPUS therapy attenuated heart fibrosis and dysfunction in diabetic mice and the effect could be largely preserved at least 12weeks after suspending LIPUS stimulation. LIPUS ameliorated diabetic heart fibrosis by inhibiting ACE-mediated NOX4-associated oxidative stress and NLRP3 inflammasome activation in cardiac fibroblasts. Our study may provide a novel therapeutic approach to hamper the progression of diabetic heart fibrosis.

Low-Intensity Pulsed Ultrasound Promotes Osteogenic Differentiation of Reamer-Irrigator-Aspirator Graft-Derived Cells in Vitro.

Recently, reamer-irrigator-aspirator (RIA) systems have been increasingly used to harvest autologous bone grafts. RIA graft materials contain bone marrow, which provides a viable source to derive large numbers of mesenchymal stem cells. Low-intensity pulsed ultrasound (LIPUS) significantly accelerates the differentiation of stem cells derived from bone marrow. This in vitro study investigated the effect of LIPUS on the osteogenic activity and differentiation of RIA graft-derived cells. A small amount of RIA graft was obtained from seven patients. After the cells derived from RIA grafts were cultured, they were divided into two groups: the LIPUS and control groups. LIPUS was applied once daily for 20 min (1.5 MHz, pulse duration: 200 µs, pulse repetition rate: 1 kHz, spatial average-temporal average intensity: 30 mW/cm2). Alkaline phosphatase activity (113.4% and 130.1% on days 7 and 14), expression of osteoblast-related genes (ALP, Runx2) and mineralization (135.2% on day 21) of the RIA graft-derived cells were significantly higher in the LIPUS group than in the control group. However, LIPUS did not affect the cell proliferation of RIA graft-derived cells. This study indicates that LIPUS may enhance the healing of non-union and critical bone defects treated by autologous bone grafting using the RIA system.

Anti-inflammatory and Neuroprotective Effects of Transcranial Ultrasound Stimulation on Parkinson's Disease.

Low-intensity pulsed ultrasound (LIPUS) is a promising non-invasive neuromodulation tool for deep brain stimulation. Here, we investigated the impact of LIPUS, including neuroprotective effects, on the pathology of Parkinson's disease (PD) in an animal model. Sprague-Dawley rats were injected with 6-hydroxydopamine (6-OHDA) at two sites in the right striatum. LIPUS (1 MHz, 5% duty cycle, 1-Hz pulse repetition frequency, 15 min/d) stimulation was then applied to some of the rats (the 6-OHDA+LIPUS group) beginning 2 wk after the 6-OHDA administration, while the remaining rats (the 6-OHDA group) received no LIPUS stimulation. The 6-OHDA-induced inflammatory responses and expressions of neurotrophic factors were quantified with immunofluorescence activity. The safety of LIPUS was assessed using hematoxylin and eosin and Nissl staining. LIPUS treatment significantly inhibited 6-OHDA-induced glial activation and the phosphorylation of nuclear factor-κB p65 in the substantia nigra pars compacta. Further study revealed that LIPUS effectively preserved the levels of neurotrophic factors, dopamine transporter and tight junction proteins of the blood-brain barrier in the 6-OHDA+LIPUS group compared with the 6-OHDA group. These results indicate that LIPUS acts via multiple neuroprotective mechanisms in the PD rat model and suggest that LIPUS can be viewed as a potential treatment for PD.

Efficacy of Low-Intensity Pulsed Ultrasound for Orthodontic Pain Control: A Randomized Clinical Trial.

Objectives: This study aimed to assess the efficacy of low-intensity pulsed ultrasound (LIPUS) for orthodontic pain control. Materials and Methods: This spilt-mouth randomized controlled clinical trial was performed on 44 mandibular first molars of 22 orthodontic patients at the Orthodontics Department of Shahid Beheshti Dental University. Elastomeric separators were placed at the mesial and distal of mandibular right and left first molars by separating pliers. Randomly, LIPUS was used at one side for 7 min and the same device with 0-degree intensity was used as sham for the other side on the facial skin. The same procedure was repeated after 24 h. Patients recorded their level of pain at 1, 6, and 24 h, and also on days 2 to 7 after, using a visual analog scale (VAS). Results: The effect of type of treatment (P=0.019), time of assessment (P<0.000) and the interaction effect of type of treatment and time of assessment (P=0.055) on the pain score were all significant. The mean pain score in the LIPUS group was significantly lower than that in the control group at 24 h (P=0.002), 4 days (P=0.031) and 5 days (P=0.035). Conclusion: LIPUS can be safely used during orthodontic treatment for pain control since it is safe, non-invasive, low-cost, and easy to use.

Low-intensity pulsed ultrasound therapy suppresses coronary adventitial inflammatory changes and hyperconstricting responses after coronary stent implantation in pigs in vivo.

We demonstrated that coronary adventitial inflammation plays important roles in the pathogenesis of drug-eluting stent (DES)-induced coronary hyperconstricting responses in pigs in vivo. However, no therapy is yet available to treat coronary adventitial inflammation. We thus developed the low-intensity pulsed ultrasound (LIPUS) therapy that ameliorates myocardial ischemia by enhancing angiogenesis. We aimed to examine whether our LIPUS therapy suppresses DES-induced coronary hyperconstricting responses in pigs in vivo, and if so, what mechanisms are involved. Sixteen normal male pigs were randomly assigned to the LIPUS or the sham therapy groups after DES implantation into the left anterior descending (LAD) coronary artery. In the LIPUS group, LIPUS (32 cycles, 193 mW/cm2) was applied to the heart at 3 different levels (segments proximal and distal to the stent edges and middle of the stent) for 20 min at each level for every other day for 2 weeks. The sham therapy group was treated in the same manner but without LIPUS. At 4 weeks after stent implantation, we performed coronary angiography, followed by immunohistological analysis. Coronary vasoconstricting responses to serotonin in LAD at DES edges were significantly suppressed in the LIPUS group compared with the sham group. Furthermore, lymph transport speed in vivo was significantly faster in the LIPUS group than in the sham group. Histological analysis at DES edges showed that inflammatory changes and Rho-kinase activity were significantly suppressed in the LIPUS group, associated with eNOS up-regulation and enhanced lymph-angiogenesis. These results suggest that our non-invasive LIPUS therapy is useful to treat coronary functional abnormalities caused by coronary adventitial inflammation, indicating its potential for the novel and safe therapeutic approach of coronary artery disease.

Low-Intensity Pulsed Ultrasound Ameliorates Neuropathic Pain Induced by Partial Sciatic Nerve Ligation Via Regulating Macrophage Polarization

Inflammatory (M1-polarized) macrophages cause neuropathic pain (NP) after nerve injury through non-resolving neuroinflammation. However, increasing evidence suggests that converting M1 to anti-inflammatory M2 macrophages may rescue NP. In the present study, the therapeutic potential of low-intensity pulsed ultrasound (LIPUS) was investigated in a partial sciatic nerve ligation (PSL)-induced NP model. Materials and Methods: Abnormal pain sensation, such as tactile allodynia, was caused by PSL. Immediately after PSL induction, the mice were subjected to LIPUS treatment for 20 min/day for 7 days. LIPUS was used at an average intensity of 60 mW/cm2 and a frequency of 1.5 MHz. Results: In the behavioral test, the LIPUS group showed a significant improvement in the PSL-induced hypersensitivity compared to the PSL group not exposed to LIPUS. We found an increasing number of M2 macrophages in the injured sciatic nerves after LIPUS exposure. LIPUS treatment decreased expression of pro-inflammatory microglial markers in spinal cord. Conclusions: Our data suggest that LIPUS has an anti-nociceptive effect by increasing anti-inflammatory M2 macrophage and may be a suitable therapeutic candidate for NP.

The effect of low intensity pulsed ultrasound on mandibular condylar growth in young adult rats

There is a need for more effective methods to enhance mandibular growth in young adults with mandibular deficiency. Previous studies suggest that low intensity pulsed ultrasound (LIPUS) can enhance mandibular growth in growing individuals. This study aimed to evaluate the potential growth changes of the mandible following 4-week LIPUS application in young adult rats. Nineteen ≈120-day-old female rats were allocated to experimental (n = 10) and control (n = 9) groups. The animals in the experimental group were treated with LIPUS to their temporomandibular joints (TMJs) bilaterally, 20 min each day for 28 consecutive days. Animals were then euthanized; gross morphological evaluation was performed on 2D photographs and 3D virtual models of hemi-mandibles, and microstructural assessment was done for the mandibular condyle (MC). Evaluation of mineralization and microarchitecture properties of subchondral cancellous bone was performed by micro-computed tomography (μCT) scanning. Qualitative and histomorphometric analysis was done on condylar cartilage and subchondral bone following Alcian Blue/PAS and Goldner's Trichrome staining. Vital flourochrome (calcein green) labeling was also utilized to determine the amount of endochondral bone growth. Gross morphological evaluations showed a slight statistically non-significant increase especially in the main condylar growth direction in the LIPUS group. Moreover, 3D evaluation depicted an enhanced periosteal bone apposition at the site of LIPUS application. Microstructural analysis revealed that LIPUS stimulates both chondrogenesis and osteogenesis and enhances endochondral bone formation in young adult rat MC. Furthermore, the effect of LIPUS on osteogenic cells of subchondral cancellous bone was notable. To conclude, LIPUS can enhance young adult rats' MC residual growth potential.

Low-Intensity Pulsed Ultrasound Promotes Repair of 4-Vinylcyclohexene Diepoxide-Induced Premature Ovarian Insufficiency in SD Rats.

Women with premature ovarian insufficiency (POI) may be more vulnerable to a variety of health risks. To seek a new method to treat the disease, the effects of low-intensity pulsed ultrasound (LIPUS) on promoting repair of ovarian injury in female SD rats induced by 4-vinylcyclohexene diepoxide (VCD) were explored in this research. A total of 24 female SD rats were subjected to intraperitoneal injection of VCD to induce POI. Successful modeling was achieved in 22 rats, which were then randomized into VCD + LIPUS group (n = 13) and VCD group (n = 9). The control group (n = 5) was injected with equal normal saline. Hematoxylin and eosin staining, enzyme-linked immunosorbent assay, Western blot analysis, scanning electron microscope, immunohistochemistry, and terminal deoxynucleotidyl transferase-mediated nick end labeling assay were applied to detect the results. The results indicated that rats in the VCD group showed disorder in the estrous cycle, the number of atresia follicles and apoptosis granulosa cells increased (p < .05). After the LIPUS treatment, the estrous cycle recovered, the number of follicles increased (p < .05), the level of E2 and anti-Müllerian hormone enhanced (p < .05), and the follicle-stimulating hormone decreased (p < .05). The expression of NF-κB p65, TNFα, Bax, ATF4, and caspase-3 in ovarian tissue was significantly decreased (p < .05). These findings showed that LIPUS could promote the repair of the VCD-induced ovarian damage in SD rats, which has the potential to be further applied in the clinic.

Low-intensity pulsed ultrasound decreases major amputation in patients with critical limb ischemia: 5-year follow-up study.

Various therapeutic strategies for angiogenesis are performed to improve symptoms in patients with critical limb ischemia (CLI). Pre-clinical studies have shown that low-intensity pulsed ultrasound (LIPUS) exposure induces angiogenesis. LIPUS may be a new stratergy for treatment of CLI. The purpose of this pilot trial was to evaluate outcomes in patients with CLI who were treated with LIPUS. Fourteen patients with CLI, who were not candidates for angioplasty or surgical revascularization, were enrolled in this study. Historical control data were obtained from the Hiroshima University PAD database. The primary endpoints were major amputation and death. The outcomes were compared in 16 lower limbs of the 14 patients with CLI who were treated with LIPUS and in 14 lower limbs of 14 patients with CLI as historical controls. All patients were followed for after 5 years after treatment with LIPUS. The mean duration of LIPUS exposure in the LIPUS group was 381± 283 days. During the 5-year follow-up periods, there were 3 major amputations and 7 deaths in the LIPUS group and there were 14 major amputations and 7 deaths in the historical control group. The overall amputation-free survival rate was significantly higher in patients who were treated with LIPUS than in historical controls. There was no significant difference between overall mortality-free survival rates in the LIPUS group and historical control group. LIPUS is a noninvasive option for therapeutic angiogenesis with the potential to reduce the incidence of major amputations in patients with CLI.

Effects of low intensity pulsed ultrasound on expression of B-cell lymphoma-2 and BCL2-Associated X in premature ovarian failure mice induced by 4-vinylcyclohexene diepoxide

BackgroundPremature ovarian failure (POF) is a common disease in the field of Gynecology. Low intensity pulsed ultrasound (LIPUS) can promote tissue repair and improve function. This study was performed to determine the effects of LIPUS on granulosa cells (GCs) apoptosis and protein expression of B-cell lymphoma-2 (Bcl-2) and BCL2-Associated X (Bax) in 4-vinylcyclohexene diepoxide (VCD)-induced POF mice and investigate the mechanisms of LIPUS on ovarian function and reserve capacity.MethodsThe current POF mice model was administrated with VCD (160 mg/kg) by intraperitoneal injection for 15 consecutive days. The mice were divided into the POF group, LIPUS group and control group. In the LIPUS group, the right ovary of mice was treated by LIPUS (acoustic intensity was 200 mW/cm2, frequency was 0.3 MHz, and duty cycle was 20%) for 20 min, 15 consecutive days from day 16. The mice of the POF group and control group were treated without ultrasonic output. The basic observation and body weight were recorded. Hematoxylin and eosin staining (H&E staining) and enzyme-linked immunosorbent assay (ELISA) were applied to detect ovarian follicle development, ovarian morphology and sex hormone secretion. Ovarian GCs apoptosis was detected by TUNEL assay and immunohistochemistry.ResultsThe results showed that VCD can induce estrus cycle disorder, follicular atresia, sex hormone secretion decreased and GCs apoptosis in mice to establish POF model successfully. LIPUS significantly promoted follicular development, increased sex hormone secretion, inhibited excessive follicular atresia and GCs apoptosis. The mechanism might be achieved by increasing the protein expression of Bcl-2 and decreasing the expression of Bax in ovaries.ConclusionsLIPUS can improve the POF induced by VCD. These findings have the potential to provide novel methodological foundation for the future research, which help treat POF patients in the clinic.

Low-intensity pulsed ultrasound enhances angiogenesis in rabbit capsule tissue that acts as a novel vascular bed in vivo.

In vivo prevascularization followed by pedicled transfer has emerged as a promising strategy for tissue engineering in recent years. We recently demonstrated that capsule tissue could serve as a novel axial in vivo vascular bed, although its high-density microvessels could only be maintained for about a week. In this present study, we aimed to demonstrate whether low-intensity pulsed ultrasound (LIPUS) promotes angiogenesis in capsule tissue. After successful induction of capsule tissue using a skin expander, 24 rabbits were randomly divided into the LIPUS group and the control group. The LIPUS group received LIPUS treatment 3 times per week. After 2 and 4 weeks of treatment, angiogenesis of the capsule tissue was assessed using in vivo and in vitro methods, including contrast-enhanced ultrasound (CEUS), photoacoustic imaging (PAI), photoacoustic microscope (PAM), and CD31 immunohistochemistry. In vivo assessments (CEUS, PAI and PAM) showed that tissue perfusion, hemoglobin content and vascular density were all significantly higher in the LIPUS group, which was consistent with CD31 immunohistochemistry. The LIPUS also promoted protein and mRNA expression of vascular endothelial growth factor α (VEGFα) and basic fibroblast growth factor (bFGF) in capsule tissue. Furthermore, cell experiments showed that LIPUS enhanced tube formation of human microvascular endothelial cells (HMECs) and promoted secretion of VEGFα and bFGF. The LIPUS treatment promoted angiogenesis of the capsule tissue by stimulating release of angiogenic factors such as VEGFα and bFGF from endothelial cells, making the capsule tissue more potent and sustained when acting as in vivo vascular bed.

Impact of photobiomodulation and low-intensity pulsed ultrasound adjunctive interventions on orthodontic treatment duration during clear aligner therapy.

To assess the efficiency of low-intensity pulsed ultrasound (LIPUS) and photobiomodulation (PBM) interventions in accelerating orthodontic tooth movement during clear aligner therapy (CAT). This retrospective study was carried out on the records of 84 subjects who were treated using CAT. Twenty-eight patients were treated using CAT with a daily use of LIPUS for 20 minutes, 28 patients were treated using CAT with a daily use of PBM for 10 minutes, and 28 patients were treated using CAT alone. The total duration of treatment was recorded for all patients. One-way analysis of variance and post hoc Tukey test were used to assess whether there was any significant difference in total treatment duration among the three groups (P < .05). The mean treatment durations in days were 719 ± 220, 533 ± 242, and 528 ± 323 for the control, LIPUS, and PBM groups, respectively. The LIPUS group showed a 26% reduction, on average, in treatment duration when compared with the control group, whereas the PBM group showed an average 26.6% reduction in the treatment duration when compared with the control group. The results showed that there were statistically significant differences among the groups (P = .011). Treatment durations were significantly reduced in the LIPUS and PBM groups as compared with the control (P = .027 and P = .023, respectively), with no statistically significant differences between the LIPUS and PBM groups (P = .998). Daily use of LIPUS or PBM as adjunctive interventions during CAT could reduce the duration of orthodontic treatment.

Osteogenic effect of low-intensity pulsed ultrasound and whole-body vibration on peri-implant bone. An experimental in vivo study.

The aims of this study were (i) to compare the osteogenic impact of low-intensity pulsed ultrasound (LIPUS) and low-magnitude high-frequency (LMHF) loading achieved with whole-body vibration (WBV) on peri-implant bone healing and implant osseointegration in rat tibiae, and (ii) to examine their combined effect on these processes. Titanium implants were inserted in the bilateral tibiae of 28 Wistar rats. Rats were randomly divided into four groups: LIPUS+WBV, LIPUS, WBV, and control. LIPUS was applied to the implant placement site for 20min/day on 5days/week (1.5MHz and 30mW/cm2 ). WBV was applied for 15min/day on 5days/week (50Hz and 0.5g). In the LIPUS+WBV group, both stimuli were applied under the same stimulation conditions as in the LIPUS and WBV groups. After 4weeks of treatment, peri-implant bone healing and implant osseointegration were assessed using removal torque (RT) tests, micro-CT analyses of relative gray (RG) value, and histomorphometrical analyses of bone-to-implant contact (BIC) and peri-implant bone formation (BV/TV). The LIPUS+WBV group had significantly greater BIC than the WBV and control groups. Although there were no significant intergroup differences in RT, RG value, and BV/TV, these variables tended to be greater in the LIPUS+WBV group than the other groups. The combination of LIPUS and LMHF loading may promote osteogenic activity around the implant. However, further study of the stimulation conditions of LIPUS and LMHF loading is necessary to better understand the osteogenic effects and the relationship between the two stimuli.

Low-Intensity Pulsed Ultrasound Prompts Both Functional and Histologic Improvements While Upregulating the Brain-Derived Neurotrophic Factor Expression after Sciatic Crush Injury in Rats

The aim of this study was to determine that low-intensity pulsed ultrasound (LIPUS) at an intensity of 140 mW/cm2 promotes functional and histologic improvements in sciatic nerve crush injury in a rat model and to investigate changes over time in relevant growth factors and receptors, exploring the mechanism of LIPUS in the recovery process after injury. Toe angle in the toe-off phase, regenerative axonal length, myelinated nerve fiber density, diameter of myelinated nerve fiber, axon diameter and myelin sheath thickness were significantly higher in the LIPUS group than in the sham group. Gene and protein expression of brain-derived neurotrophic factor (BDNF) was upregulated in the LIPUS group. In conclusion, LIPUS contributed to rapid functional and histologic improvement and upregulated BDNF expression after sciatic nerve crush injury in rats.

Low-intensity pulsed ultrasound alleviating myelosuppression of Sprague-Dawley rats after combined treating by paclitaxel and carboplatin.

BackgroundOur team has previously reported that low intensity pulsed ultrasound (LIPUS) can alleviate myelosuppression in rats induced by single chemotherapy drugs. But in clinics, chemotherapy is often performed with multiple drugs simultaneously. To be closer to the clinical status quo, this experiment was designed to show whether it was the same effect of LIPUS on myelosuppression caused by combination therapy of chemotherapy drugs.MethodsThe rat model of myelosuppression was established by continuous injection of paclitaxel and carboplatin for 4 days. These myelosuppressive rats were randomly divided into LIPUS group (n=40) and control group (n=40). The LIPUS group was given continuous LIPUS irradiation for 7 days, while the control group was given sham irradiation (no energy output). The evaluation of blood cells counts, Hematoxylin-Eosin staining (H&E staining), scanning electron microscopy, enzyme-linked immunosorbent assay (ELISA) and real-time quantitative PCR (qPCR) was then performed.ResultsThe results showed in the LIPUS group the blood cells count, hematopoietic tissue of bone marrow, the colonies formed from adhering of bone marrow stromal cells, levels of hematopoietic regulators and adhesion molecules all increased (LIPUS group vs. control group, P<0.05).ConclusionsThe results indicated that LIPUS can relieve myelosuppression induced by combined treatment of paclitaxel and carboplatin. The mechanisms may be LIPUS can increase the levels of hematopoietic regulators and adhesion molecules.

Low-Intensity Pulsed Ultrasound Suppresses Synovial Macrophage Infiltration and Inflammation in Injured Knees in Rats

This study was designed to investigate how low-intensity pulsed ultrasound (LIPUS) suppresses traumatic joint inflammation and thereafter affects the progression of posttraumatic osteoarthritis. Intra-articular fracture (IAF) was created in the right knee of rats. LIPUS was applied to the knees with IAFs for 20 min/d for 2 wk—LIPUS(+) group. The study controls included rats that underwent sham surgery but no LIPUS treatment (control group) or underwent IAF surgery without LIPUS treatment—LIPUS(–) group. By histology, at 4 wk, leukocyte infiltration in the synovium was reduced in the LIPUS(+) group. Furthermore, LIPUS treatment reduced CD68+ macrophages in the synovium and limited their distribution mostly in the subintimal synovium. Measured with enzyme-linked immunosorbent assay, interleukin-1β (IL-1β) in the joint fluid of the LIPUS(+) group was reduced to about one-third that in the LIPUS(–) group. By reducing synovial macrophages and lowering IL-1β in the joint fluid, LIPUS is potentially therapeutic for posttraumatic osteoarthritis.

Low intensity pulsed ultrasound information technology intervention in diagnosis and prediction of Muscle Atrophy.

Objective:To discuss the effects and function of LIPUS on muscle atrophy (MA), analysis from various aspects through the study of low-intensity pulsed ultrasound (LIPUS) information technology intervention (ITI) in diagnosis and the prediction of muscle atrophy..Method:In this study conducted in our university, 74 healthy female SD rats aged three months, weighing 100-200g were selected. All rats were placed in sterile cages from June 2020 to September 2020. They were divided into three groups. In the OVO group and OVE group, the mice are treated with LIPUS, Finally, the changes of body weight, grasping power, biochemical indexes and glycogen content of gastrocnemius muscle were analyzed and recorded to explore the effect and value of LIPUS ITI combined with intermittent weight-bearing exercise in the treatment of MAResults:After weight-bearing running, the body weight of model (OVO) group, exercise (OVE) group and NC group had significant statistical significance (P<0.01). It was found that the weight of OVE group was much more as compared to OVO group. There was significant difference in body weight between OVO group and NC group (P<0.05). After LIPUS treatment, it was found that the weight of OVO group, OVE group, LIPUS group and OVE +LIPUS group increased. Compared with the NC group, there was significant statistical difference (P<0.01).Conclusion:Low intensity pulsed ultrasound ITI has a good effect on improving MA, so as to effectively improve the weight of gastrocnemius muscle. The combined application of the two is better for the improvement of muscular atrophy.

Effects of Low-Intensity Pulsed Ultrasound on Myelosuppression of Rats Induced by Chemotherapy Drugs With Cell Cycle Specificity.

To explore the ameliorating effects of low-intensity pulsed ultrasound (LIPUS) on Sprague Dawley rat myelosuppression induced by cell cycle specificity drugs (docetaxel, mitotic phase sensitive; and etoposide, gap 2 phase sensitive). Rats were respectively administered docetaxel (100 mg/kg) or etoposide (110 mg/kg) by intraperitoneal injection for 4 consecutive days. Then the rats were divided randomly into a LIPUS group and a non-LIPUS group. In the LIPUS group, the right femoral metaphysis of rats was treated by LIPUS (acoustic intensity, 200 mW/cm2 ; frequency, 0.3 MHz; and duty cycle, 20%) for 20 minutes on 7 consecutive days from day 5. The rats of the non-LIPUS group were treated without ultrasound output. A blood cell count, an enzyme-linked immunosorbent assay, a real-time quantitative polymerase chain reaction, and hematoxylin-eosin staining were applied to detect the results. Low-intensity pulsed ultrasound significantly promoted the counts of bone marrow nucleated cells, white blood cells, immunoglobulin A (IgA), IgG, granulocyte colony-stimulating factor, stem cell factor, and intercellular cell adhesion molecule 1 and reduced the counts of vascular cell adhesion molecule 1 whether in the docetaxel or etoposide group (P < .05). Low-intensity pulsed ultrasound only increased the expression level of IgM in the docetaxel group but decreased the level of interleukin 6 in the etoposide group (P < .05). Low-intensity pulsed ultrasound has potential to be a noninvasive treatment for myelosuppression caused by different cell cycle-sensitive chemotherapy drugs.