Intrarenal delivery of bFGF-loaded liposome under guiding of ultrasound-targeted microbubble destruction prevent diabetic nephropathy through inhibition of inflammation.

Basic fibroblast growth factor (bFGF) has shown great therapeutic effects for diabetic nephropathy (DN). However, its clinical applications are limited due to its short half-life, low stability and poor penetration. Herein, a bFGF-loaded liposome (bFGF-lip) was constructed and combined with ultrasound-targeted microbubble destruction (UTMD) to overcome these drawbacks. bFGF-lip exhibited spherical morphology with a diameter of 171.1 ± 14.2 nm and a negative zeta potential of -5.15 ± 2.08 mV, exhibiting a sustained-release profile of bFGF. DN rat models were successfully induced by streptozotocin. After treatment with bFGF-lip + UTMD, the concentration of bFGF in kidney of DN rats was significantly enhanced in comparison with free bFGF treatment. Additionally, the morphology and the function of the kidneys were obviously recovered after bFGF-lip + UTMD treatment as shown by ultrasonography and histological analyse. The molecular mechanism was associated with the inhibition of renal inflammation. After treatment with bFGF-lip + UTMD, the activation of NF-κB was obviously reduced in the renal tissues, and downstream inflammatory mediators including TGF-ß1, MCP-1, IL-6 and IL-1ß were also down regulated. In addition, inflammation-induced cellular apoptosis of renal tubular cells was also significantly inhibited by detecting Bax, caspase-3 and Bcl-2. Therefore, bFGF-lip in combination with UTMD might be a potential strategy to reverse the progression of early DN.

Combination of coenzyme Q10-loaded liposomes with ultrasound targeted microbubbles destruction (UTMD) for early theranostics of diabetic nephropathy.

Diabetic nephropathy (DN) is one of the most common and lethal microvascular complications of diabetes. This study aimed to explore whether coenzymeQ10 (CoQ10) as an antioxidant combined with ultrasound-targeted microbubble destruction (UTMD) could reverse the progress of early diabetic nephropathy (DN). CoQ10 has great potential to treat early DN. However, the clinical application of CoQ10 has been limited because of its low aqueous solubility and non-specific distribution. Therefore, CoQ10-loaded liposomes (CoQ10-lip) were prepared and combined with ultrasound microbubbles for the early theranostics of DN. CoQ10-lip exhibited a good round morphology with a diameter of 183±1.7nm and a negative zeta potential of -25.3mV, which was capable of prolonging the release of the encapsulated CoQ10. The early DN rat models were induced by streptozotocin (STZ) and confirmed by contrast-enhanced ultrasound (CEUS) and 24-h urinary albumin. After the administration of CoQ10-lip combined with the UTMD technique to rats with early DN, the morphology and function of the kidney were evaluated by ultrasonography, histological and molecular analyses. The renal hemodynamics were significantly improved, moreover, 24-h urinary protein, and oxidative stress indexes were modulated after treatment with CoQ10-lip+UTMD indicating recovery of renal function. An elevated level of Nphs2 protein and reduced caspase 3 level indicated the preservation of podocytes and inhibition of cell apoptosis after CoQ10-lip+UTMD treatment. The molecular mechanism was associated with the upregulation of Bcl-2 and the downregulation of Bax. Moreover, the combination of CoQ10-lip and ultrasound microbubbles demonstrated a better protective effect on the damaged kidney than the other groups (free CoQ10 or CoQ10-lip+/- UTMD). Conclusively, CoQ10-lip in combination with ultrasound microbubbles might be a potential strategy to reverse the progress of early DN.