Low-intensity shockwave therapy in the treatment of diabetic nephropathy: a prospective Phase 1 study

Low-Intensity Shockwave Therapy (LI-ESWT) in Diabetic Kidney Disease: Results from an Open-Label Interventional Clinical Trial

Purpose

Treatment with low-intensity shockwave therapy (LI-ESWT) is associated with angiogenesis and is suggested as a treatment for different types of vascular diseases. It was hypothesized that LI-ESWT improves the renal filtration barrier and halts the progression of GFR decline in diabetic kidney disease (DKD) potentially through VEGF and NO formation. We present the first data on LI-ESWT in human DKD.

Methods

The study was designed as an interventional, prospective, one-arm, Phase 1 study. We investigated change in GFR and albuminuria in 28 patients with DKD treated with six sessions of LI-ESWT over three weeks. The patients were followed for six months. Urine excretion of kidney injury markers, vascular endothelial growth factor (VEGF) and nitric oxide metabolites (NOx) was studied after LI-ESWT.

Results

There were no significant changes in GFR and albuminuria up to six months after LI-ESWT compared to baseline. Urine VEGF was transiently reduced one month after LI-ESWT, but there were no other significant changes in urine VEGF or NOx after LI-ESWT. Secondary analysis showed that NOx increased after LI-ESWT in patients who had low levels of NOx at baseline. Kidney injury marker trefoil factor 3 (TFF3) increased acutely after the first session of LI-ESWT indicating transient endothelial repair. Other markers of kidney injury were stable in relation to LI-ESWT.

Conclusion

LI-ESWT treatment did not significantly improve kidney function and albumin excretion. It is concluded that LI-ESWT is not harmful. A randomized blinded study should be performed to clarify whether adjunctive treatment with LI-ESWT is superior to standard treatment of DKD.

It Comes As a Shock: Kidney Repair Using Shockwave Therapy

Chronic kidney disease is a global health care burden, yet clinically-proven treatments are limited. Low-intensity shockwave, which utilizes ≈10% of the energy levels used in clinically indicated shockwave lithotripsy, is a promising technique to ameliorate ischemia and regenerate tissues. It has been demonstrated to improve healing in tissues such as bone, muscle, myocardium, and kidney via several mechanisms, particularly through promoting neovascularization. Low-intensity shockwave stimulates mechanoreceptors located primarily in endothelial and proximal tubular cells and subsequently upregulates vascular endothelial growth factors. This, in turn, promotes angiogenesis and ameliorates renal hypoxia, inflammation, and fibrosis, and ultimately preserves renal function. Furthermore, low-intensity shockwave can stimulate release of homing factors to attract endothelial progenitor or stem cells into injured kidneys for tissue repair. These effects may be beneficial in several kidney disease models, including renal artery stenosis, diabetic kidney disease, and various chronic kidney diseases, although most studies reported to date have been performed in animal models. Because of its low energy intensity, the procedure is relatively tolerable and safe, yet, more clinical studies are needed to establish its efficacy beyond currently existing strategies. Therefore, low-intensity shockwave therapy emerges as an alternative therapeutic approach that may offer a promising noninvasive intervention for treating renal diseases. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02515461; NCT03602807; and NCT03445247.

Novel therapeutic strategies for renovascular disease

PURPOSE OF REVIEW

Renovascular disease (RVD) remains an important cause of hypertension and renal dysfunction. Given the failure of renal revascularization to provide consistent clinical benefit in the Cardiovascular Outcomes for Renal Artery Lesions trial among others, further research has underscored the need for mechanistically targeted interventions to improve renal outcomes in patients in RVD. This review discusses novel therapeutic approaches for RVD in the post-Cardiovascular Outcomes for Renal Artery Lesions era.

RECENT FINDINGS

Emerging evidence indicates that renal inflammation, microvascular remodeling, and mitochondrial damage accelerate progression of renal injury and are important determinants of the response to revascularization. Experimental studies have identified interventions capable of ameliorating renal inflammation (e.g., cytokine inhibitors, mesenchymal stem cells), microvascular remodeling (proangiogenic interventions), and mitochondrial injury (mito-protective drugs), alone or combined with renal revascularization, to preserve the structure and function of the poststenotic kidney. Recent prospective pilot studies in patients with atherosclerotic RVD demonstrate the safety and feasibility of some of such interventions to protect the kidney.

SUMMARY

Experimental studies and pilot clinical trials suggest that therapies targeting renal inflammation, microvascular remodeling, and mitochondrial damage have the potential to preserve the structure and function of the stenotic kidney. Further studies in larger cohorts are needed to confirm their renoprotective effects and clinical role in human RVD.

Low-Energy Extracorporeal Shock Wave Therapy Ameliorates Kidney Function in Diabetic Nephropathy

Background

Diabetic nephropathy is the most common cause of end-stage renal disease. Traditional therapy for diabetic nephropathy has focused on supportive treatment, and there is no significant effective therapy. We investigated the effect of low-energy extracorporeal shock wave therapy on a diabetic nephropathy rat model.

Methods

Streptozotocin-induced diabetic nephropathy rats were treated with six sessions of low-energy extracorporeal shock wave therapy (weekly for six consecutive weeks) or left untreated. We assessed urinary creatinine and albumin, glomerular volume, renal fibrosis, podocyte number, renal inflammation, oxidative stress, and tissue repair markers (SDF-1 and VEGF) six weeks after the completion of treatment.

Results

The six-week low-energy extracorporeal shock wave therapy regimen decreased urinary albumin excretion as well as reduced glomerular hypertrophy and renal fibrosis in the rat model of diabetic nephropathy. Moreover, low-energy extracorporeal shock wave therapy increased podocyte number in diabetic nephropathy rats. This was likely primarily attributed to the fact that low-energy extracorporeal shock wave therapy reduced renal inflammation and oxidative stress as well as increased tissue repair potency and cell proliferation.

Conclusions

Low-energy extracorporeal shock wave therapy preserved kidney function in diabetic nephropathy. Low-energy extracorporeal shock wave therapy may serve as a novel noninvasive and effective treatment of diabetic nephropathy.