Recent data suggest that the phosphatidylinositol 3-kinase (PI3-K)/Akt/mammalian target of rapamycin (mTOR) pathway is important in diabetic nephropathy. The effect of mTOR blockade by sirolimus (SRL) in diabetic kidney disease in rats was investigated. Diabetes was induced by streptozotocin in male Sprague-Dawley rats. Sixteen weeks later, diabetic animals were divided into the following groups: diabetes (D; n ‫؍‬ 8), diabetes ؉ SRL at 1 mg/kg per d, SRL trough level 2.3 ؎ 0.25 ng/ml (D؉SRL; n ‫؍‬ 7); and diabetes ؉ normoglycemia maintained by insulin implants (D؉NG; n ‫؍‬ 5). There was an age-matched nondiabetic group (ND; n ‫؍‬ 6). All animals were followed for 4 wk. The D group showed glomerular hypertrophy (mean glomerular volume 5.0 ؎ 0.4 in D versus 3.3 ؎ 0.2 10 6 3 in ND; P < 0.05) without renal hyperplasia (calculated by reverse transcription-PCR of proliferative cell nuclear antigen) and albuminuria (29 ؎ 4 in D versus 1.4 ؎ 1.5 mg/24 h in ND; P < 0.05). Both D؉NG and D؉SRL groups had a significant reduction of albuminuria, although glomerular hypertrophy was still present. SRL treatment did not modify the number of infiltrating renal ED1 ؉ cells. Diabetic animals had greater expression of p-Akt and mTOR, unlike ND rats. NG and SRL treatment reduced p-Akt and normalized mTOR. It is interesting that D؉SRL was associated with a significant reduction of renal TGF-␤1 and glomerular connective tissue growth factor. SRL treatment reduced glomerular ␣-smooth muscle actin overexpression and reduced significantly the mesangial matrix accumulation that is characteristic of diabetic nephropathy. In conclusion, mTOR blockade by low-dose SRL has a beneficial effect in diabetic kidney disease, suggesting that the mTOR pathway has an important pathogenic role in diabetic nephropathy.

Diabetic nephropathy is the main cause of end-stage renal disease requiring dialysis in developed countries.In this study, we demonstrated the therapeutic effect of hepatocyte growth factor (HGF) on advanced rather than early diabetic nephropathy using a rat model of streptozotocin-induced diabetes. Early diabetic nephropathy (16 weeks after induction of diabetes) was characterized by albuminuria, hyperfiltration, and glomerular hypertrophy, whereas advanced diabetic nephropathy showed prominent transforming growth factor (TGF)-␤1 upregulation, mesangial expansion, and glomerulosclerosis. An SP1017-formulated human HGF (hHGF) plasmid was administered by intramuscular injection combined with electroporation over a 30-day follow-up in rats with early and advanced diabetic nephropathy. hHGF gene therapy upregulated endogenous rat HGF in the diabetic kidney (rat HGF by RT-PCR was threefold higher than in diabetic rats without therapy). hHGF gene therapy did not improve functional or morphologic abnormalities in early diabetic nephropathy. hHGF gene therapy reduced albuminuria and induced strong regression of mesangial expansion and glomerulosclerosis in advanced diabetic nephropathy. These findings were associated with suppression of renal TGF-␤1 and mesangial connective tissue growth factor (CTGF) upregulation, inhibition of renal tissue inhibitor of metalloproteinase (TIMP)-1 expression, and reduction of renal interstitial myofibroblasts. In conclusion, our results suggest that hHGF gene therapy may be considered as an innovative therapeutic strategy to treat advanced diabetic nephropathy.

Renal involvement in systemic lupus erythematosus is a common complication that significantly worsens morbidity and mortality. Although treatment with corticosteroids and cytotoxic drugs may be useful in many cases, morbidity associated with these drugs and the relapsing nature of the disease make it necessary to develop new treatment strategies. Five-month old female NZB/W F1 mice were divided into the following groups: CYP group (n = 10), cyclophosphamide (CYP) 50 mg/kg intraperitoneally every 10 days; RAPA 1 group (n = 10) oral daily sirolimus (SRL), 1 mg/kg; RAPA 12 group (n = 13), oral daily SRL, 12mg/kg; FTY group (n = 10), oral fingolimod (FTY720), 2 mg/kg three times per week. An additional group of 13 non-treated mice were used as a control (control group). Follow-up was performed over four months. Animal survival, body weight, anti-DNA antibodies and proteinuria were determined. Kidneys were processed for conventional histology and immunofluorescence for IgG and complement. Total histological score (HS) was the sum of mesangial expansion, endocapillary proliferation glomerular deposits, extracapillary proliferation, interstitial infiltrates, tubular atrophy and interstitial fibrosis. All treated groups had lower proteinuria at the end of the follow-up with respect to the control group (P < 0.0001). Serum anti-DNA antibodies were appropriately controlled in RAPA 1 and CYP groups, but not in FTY or RAPA 12 groups. SRL and CYP arrested, and perhaps reversed almost all histological lesions. FTY720 ameliorated histological lesions but did not control mesangial expansion or interstitial infiltrates. SRL produces great improvement in murine lupus nephritis, while FTY720 seems a promising alternative if used in appropriate doses.

ObjectivesRisankizumab is an interleukin-23 inhibitor under study for the treatment of patients with psoriatic arthritis (PsA). The phase 3 KEEPsAKE 2 trial investigated the efficacy and safety of risankizumab versus placebo in patients with active PsA who had previous inadequate response or intolerance to ≤2 biological therapies (Bio-IR) and/or ≥1 conventional synthetic disease-modifying antirheumatic drug (csDMARD-IR). Results through week 24 are reported here.MethodsAdults with PsA who were Bio-IR and/or csDMARD-IR were randomised to receive subcutaneously administered risankizumab 150 mg or placebo at weeks 0, 4 and 16 during a 24-week, double-blind treatment period. The primary endpoint was the proportion of patients who achieved ≥20% improvement in American College of Rheumatology score (ACR20) at week 24. Secondary endpoints assessed key domains of PsA and patient-reported outcomes.ResultsA total of 444 patients (median age 53 years, range 23–84 years) were randomised to risankizumab (n=224) or placebo (n=220); 206 patients (46.5%) were Bio-IR. At week 24, a significantly greater proportion of patients receiving risankizumab achieved the primary endpoint of ACR20 (51.3% vs 26.5%, p<0.001) and all secondary endpoints (p<0.05) compared with placebo. Serious adverse events were reported for 4.0% and 5.5% of risankizumab-treated and placebo-treated patients, respectively; serious infections were reported for 0.9% and 2.3%, respectively.ConclusionTreatment with risankizumab resulted in significant improvements versus placebo in key disease outcomes and was well tolerated in patients with PsA who were Bio-IR and/or csDMARD-IR.Trial registration numberNCT03671148.