Effects of Therapy with Light Emitting Diode (LED) in the Calcaneal Tendon Lesions of Rats: A Literature Review

Effects of light-emitting diode therapy on hand stiffness and pain in non-steroidal anti-inflammatory drug-refractory patients with tenosynovitis

Objective

The objective of this study was to evaluate the safety and efficacy of light-emitting diode therapy (LEDT) in the management of pain and stiffness in patients with refractory hand tenosynovitis to non-steroidal anti-inflammatory drugs.

Methods

A total of 12 patients were enrolled in the study and received LEDT twice a week for four weeks. Sociodemographic, clinical, and laboratory data were collected, and the visual analog scale (VAS) pain and stiffness scores of each hand were assessed every two weeks. The thickness of the flexor tendon in the patients' hand was evaluated using ultrasonography. To investigate the molecular effects of LEDT, we measured the expression levels of type III collagen in tendon cells, with and without LEDT treatment.

Results

After undergoing LEDT, participants showed clinically significant improvements in VAS pain scores at weeks 2, 4, and 8 compared to their baseline, and in VAS stiffness scores at weeks 4 and 8. According to the ultrasonography results, there was a decreasing tendency in tendon thickness for each finger in week 8 compared to the baseline, but the difference was not statistically significant. No adverse events were reported. Additionally, our results indicated a significant increase in type III collagen levels in the LEDT group compared to the control group (1.48±0.18 vs. 0.99±0.02, p=0.031), indicating a potential molecular mechanism for the observed clinical improvements.

Conclusion

LEDT may provide a viable alternative to pharmacological treatments in the future, due to its simple and easy method of administration.

Production, immobilization and application of invertase from new wild strain Cunninghamella echinulata PA3S12MM

AIMS

The objective of this study was to determine the best conditions to produce invertase by Cunninghamella echinulata PA3S12MM and to immobilize and apply the enzyme.

METHODS AND RESULTS

The maximum production was verified in 8 days of cultivation at 28°C supplemented with 10 g L^-1 apple peel, reaching 1054.85 U ml^-1 . The invertase was purified from the DEAE-Sephadex column. The derivative immobilized in alginate-gelatin-calcium phosphate showed reusability >50% for 19 cycles. The derivative immobilized in glutaraldehyde-chitosan showed greater thermostability and at a different pH. The hydrolysis of 15 ml of sucrose 500 g L^-1 in a fixed bed reactor (total volume of 31 ml) produced 24.44 µmol min^-1 of glucose and fructose at a residence time of 30 min and a conversion factor of 0.5.

CONCLUSIONS

The new wild strain C. echinulata PA3S12MM presents high invertase production in medium supplemented with an agro-industrial residue and the immobilized enzyme showed high thermal stability and resistance at a different pH.

SIGNIFICANCE AND IMPACT OF THE STUDY

The fungus C. echinulata PA3S12MM is an excellent producer of invertases in Vogel medium supplemented with apple peel. The enzyme is promising for industrial application since it has good performance in reusability and inverted sugar production.

The effect of low-level red and near-infrared photobiomodulation on pain and function in tendinopathy: a systematic review and meta-analysis of randomized control trials

Background

Tendinopathy is a common clinical condition that can significantly affect a person’s physical function and quality of life. Despite exercise therapy being the mainstay of tendinopathy management, there are many potential adjunct therapies that remain under investigated, one of which is photobiomodulation (PBM). PBM uses varied wavelengths of light to create a biological effect. While PBM is used frequently in the management of tendinopathy, high quality evidence supporting its utility is lacking.

Methods

A systematic search of the Pubmed, CINAHL, SCOPUS, Cochrane Database, Web of Science and SPORTSDICUS databases was performed for eligible articles in August 2020. Randomized Control Trials that used red or near-infrared PBM to treat tendinopathy disorders that made comparisons with a sham or ‘other’ intervention were included. Pain and function data were extracted from the included studies. The data were synthesized using a random effects model. The meta-analysis was performed using the mean difference (MD) and standardized mean difference (SMD) statistics.

Results

A total of 17 trials were included (n = 835). When compared solely to other interventions PBM resulted in similar decreases in pain (MD -0.09; 95% CI − 0.79 to 0.61) and a smaller improvement in function (SMD -0.52; 95% CI − 0.81 to − 0.23). When PBM plus exercise was compared to sham treatment plus exercise, PBM demonstrated greater decreases in pain (MD 1.06; 95% CI 0.57 to 1.55) and improved function (MD 5.65; 95% CI 0.25 to 11.04). When PBM plus exercise was compared to other interventions plus exercise, no differences were noted in pain levels (MD 0.31; 95% CI − 0.07 to 0.70). Most studies were judged as low-risk of bias. The outcome measures were classified as very low to moderate evidence quality according to the Grading of Recommendation, Development and Evaluation tool.

Conclusion

There is very-low-to-moderate quality evidence demonstrating that PBM has utility as a standalone and/or adjunctive therapy for tendinopathy disorders.

Trial registration

PROPERO registration number: CRD42020202508.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-021-00306-z.

Effect of low intensity photobiomodulation associated with norbixin-based poly (hydroxybutyrate) membrane on post-tenotomy tendon repair. In vivo study

Purpose:

To evaluate the in vivo response of photobiomodulation therapy associated with norbixin-based poly(hydroxybutyrate) membrane (PHB) in tenotomized calcaneal tendon.

Methods:

Thirty rats were randomly allocated to six groups (n=5 each): LED groups (L1, L2 and L3) and membrane + LED groups (ML1, ML2 and ML3). The right calcaneal tendons of all animals were sectioned transversely and were irradiated with LED daily, one hour after surgery every 24 hours, until the day of euthanasia. At the end of the experiments the tendons were removed for histological analysis.

Results:

The histological analysis showed a significant reduction in inflammatory cells in the ML1, ML2 and ML3 groups (p=0.0056, p=0.0018 and p<0.0001, respectively) compared to those in the LED group. There was greater proliferation of fibroblasts in the ML1 (p<0.0001) and L3 (p<0.0001) groups. A higher concentration of type I collagen was also observed in the ML1 group (p=0.0043) replacing type III collagen.

Conclusion:

Photobiomodulation in association with norbixin-based PHB membrane led to control of the inflammatory process. However, it did not favor fibroblast proliferation and did not optimize type I collagen formation in the expected stage of the repair process.

Inhibitory effect of red LED irradiation on fibroblasts and co-culture of adipose-derived mesenchymal stem cells

The objective of this study was to evaluate the effects of red Light Emiting Diode (red LED) irradiation on fibroblasts in adipose-derived mesenchymal stem cells (ASC) co-culture on the scratch assay. We hypothesized that red LED irradiation could stimulate paracrine secretion of ASC, contributing to the activation of genes and molecules involved in cell migration and tissue repair. ASC were co-cultured with NIH/3T3 fibroblasts through direct contact and subjected to red LED irradiation (1.45 J/cm²/5min6s) after the scratch assay, during 4 days. Four groups were established: fibroblasts (F), fibroblasts + LED (FL), fibroblasts + ASC (FC) and fibroblasts + LED + ASC (FLC). The analyzes were based on Ctgf and Reck expression, quantification of collagen types I and III, tenomodulin, VEGF, TGF-β1, MMP-2 and MMP-9, as well as viability analysis and cell migration. Higher Ctgf expression was observed in FC compared to F. Group FC presented higher amount of tenomodulin and VEGF in relation to the other groups. In the cell migration analysis, a higher number of cells was observed in the scratched area of the FC group on the 4^th day. There were no differences between groups considering cell viability, Reck expression, amount of collagen types I and III, MMP-2 and TGF-β1, whereas TGF-β1 was not detected in the FC group and the MMP-9 in none of the groups. Our hypothesis was not supported by the results because the red LED irradiation decreased the healing response of ASC. An inhibitory effect of the LED irradiation associated with ASC co-culture was observed with reduction of the amount of TGF-β1, VEGF and tenomodulin, possibly involved in the reduced cell migration. In turn, the ASC alone seem to have modulated fibroblast behavior by increasing Ctgf, VEGF and tenomodulin, leading to greater cell migration. In conclusion, red LED and ASC therapy can have independent effects on fibroblast wound healing, but the combination of both does not have a synergistic effect. Therefore, future studies with other parameters of red LED associated with ASC should be tested aiming clinical application for tissue repair.