Can the Realization of an External Wirsungostomy be an Option for High-Risk Pancreatic Anastomosis After Pancreaticoduodenectomy?

BACKGROUND: Clinically relevant postoperative pancreatic fistula (POPF) occurs in 15-20% of patients after pancreaticoduodenectomy (PD) and reintervention in the setting of Grade C POPF remains associated with a mortality rate of up to 25%. In patients at high risk of POPF, PD with external wirsungostomy (EW) could be a safe alternative that avoids pancreatico-enteric anastomosis while preserving the remnant pancreas. METHODS: Of the 155 consecutive patients who underwent PD from November 2015 to December 2020, 10 patients were managed using an EW, all with a fistula risk score (FRS) ≥ 7 and BMI ≥30 kg/m2, and/or major associated abdominal surgery. The pancreatic duct was cannulated with a polyethylene tube to allow good external drainage of the pancreatic fluid. We retrospectively analyzed postoperative complications and endocrine and exocrine insufficiencies. RESULTS: The median alternative FRS was 36.9% [22.1-45.2]. There was no postoperative death. The 90-day overall severe complication (grade ≥3) rate was 30% (n = 3 patients), no patient required reoperation, and 2 hospital readmissions occurred. 3 patients experienced Grade B POPF (30%), managed using image-guided drainage for 2 patients. The external pancreatic drain was removed after a median drainage time of 75 days [63-80]. Two patients presented with late symptoms (> 6 months) warranting interventional management (pancreaticojejunostomy and transgastric drainage). Six patients experienced significant weight loss (> 2 kg) 3 months after surgery. One year after surgery, 4 patients still complained of diarrhea and were treated with transit-delaying drugs. One patient presented new-onset diabetes one year after surgery, and 1 of the 4 patients with preexisting diabetes experienced worsening disease. CONCLUSION: EW after PD might be a solution to reduce post-operative mortality following PD in high-risk patients.

Methodological and ethical quality of surgical trials from 2016 to 2020.

PURPOSE: Randomized controlled trials (RCTs) are the gold standard tool used to evaluate therapeutic interventions. The published results showed that progress still needs to be made not only from a methodological point of view but also from an ethical point of view. The aim of this study was to evaluate the methodological and ethical qualities of randomized clinical trials in surgery over the last few years. METHODS: All of the articles chosen for review reported on randomized controlled surgical trials and were published in 10 international journals between 2016 and 2020. Eligible studies were identified, selected, and then evaluated based on a broad set of predetermined criteria. Methodological quality was evaluated using the Jadad scale, and ethical quality was evaluated using the Berdeu score. RESULTS: The methodological quality score (Jadad scale) ranged from 5 to 13, with a mean of 10.0 ± 1.54. The methodological quality was insufficient (score ≤ 9) for 162 trials (31.2%). The ethical quality score ranged from 0.25 to 1, with a mean of 0.8 ± 0.11. Fifty-two articles (10%) did not state that informed consent was requested from the participants, and 21 articles (4%) did not report either research ethics committee or institutional committee protocol approval. CONCLUSION: The randomized clinical surgical trials analyzed showed that they had satisfactory methods in only 70% of the cases and that they had respected the fundamental ethical principles in 90% of the cases. However, less than 8% of the studies reported planned interim analysis, prospectively defined stopping rules, and independent monitoring committee.

Antineutrophil Cytoplasm Antibody-Associated Vasculitides Valvular Impairment: Multicenter Retrospective Study and Systematic Review of the Literature.

OBJECTIVE: While myocardial impairment is a predictor of poor prognosis in antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV), little is known about valvular involvement. This study aims at describing the clinical presentation, management, and outcome of endocarditis associated with AAV. METHODS: We conducted a multicenter retrospective study in centers affiliated with the French Vasculitis Study Group. We included patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), or eosinophilic GPA with endocardial impairment. A systematic review was then performed through PubMed, Embase, and Cochrane Library from inception up to September 2020. RESULTS: The retrospective cohort included 9 patients (82%) with GPA, 1 (9%) with MPA, and 1 (9%) with unclassified AAV. Clinical presentation included acute valvular insufficiency (n = 7, 64%), cardiac failure (n = 3, 27%), dyspnea (n = 3, 27%), and no symptoms (n = 2, 18%). The aortic valve was the most frequently affected (n = 8/10, 80%), and vegetations were noted in 4 of 10 patients (40%). Six patients (55%) underwent surgical valvular replacement. No death from endocarditis was reported. The systematic review retrieved 42 patients from 40 references: 30 (71%) had GPA, 21 (50%) presented with vegetations, the aortic valve (n = 26, 62%) was the most frequently involved. Valvular replacement was required in 20 cases (48%) and 5 patients (13%) died from the endocarditic impairment. CONCLUSION: Endocarditis is a rare and potentially life-threatening manifestation of AAV. Acute valvular insufficiency may lead to urgent surgery. Implementing transthoracic echocardiography in standard assessment at baseline and follow-up of AAV might reduce the delay to diagnosis and allow earlier immunosuppressive treatment before surgery is needed.

Total Pelvic Exenteration, Cytoreductive Surgery, and Hyperthermic Intraperitoneal Chemotherapy for Rectal Cancer with Associate Peritoneal Metastases: Surgical Strategies to Optimize Safety.

BACKGROUND: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a curative treatment option for patients with peritoneal carcinomatosis. Total pelvic exenteration (TPE) is an established treatment option for locally advanced pelvic malignancy. These two procedures have high mortality and morbidity, and therefore, their combination is not currently recommended. Herein, we reported our experience on TPE associated with CRS/HIPEC with a critical analysis for rectal cancer with associate peritoneal metastases. METHODS: From March 2006 to August 2020, 319 patients underwent a CRS/HIPEC in our hospital. Among them, 16 (12 men and four women) underwent an associated TPE. The primary endpoints were perioperative morbidity and mortality. RESULTS: There was locally recurrent rectal cancer in nine cases, six locally advanced primary rectal cancer, and a recurrent appendiceal adenocarcinoma. The median Peritoneal Cancer Index (PCI) was 8. (4-16). Mean duration of the surgical procedure was 596 min (420-840). Complete cytoreduction (CC0) was achieved in all patients, while clear resection (R0) margins on the resected pelvic organs were achieved in 81.2% of cases. The median hospital stay was 46 days (26-129), and nine patients (56.2%) experienced severe complications (grade III to V) that led to death in two cases (12.5%). The total reoperation rate for patients was 6/16 (37.5%) and 3/16 (18.75%) with percutaneous radiological-guided drainage. CONCLUSIONS: In summary, TPE/extended TPE (ETPE) associated with CRS/HIPEC may be a reasonable procedure in selected patients at expert centers. Pelvic involvement should not be considered a definitive contraindication for CRS/HIPEC in patients with resectable peritoneal surface diseases if a R0 resection could be achieved on all sites. However, the morbidity and the mortality are high with this combination of treatment, and further research is needed to assess the oncologic benefit and quality of life before such a radical approach can be recommended.

Chronic kidney failure mineral bone disorder leads to a permanent loss of hematopoietic stem cells through dysfunction of the stem cell niche.

In chronic kidney disease (CKD), endothelial injury, is associated with disease progression and an increased risk for cardiovascular complications. Circulating cells with vascular reparative functions are hematopoietic and also reduced in CKD. To explore the mechanistic basis behind these observations, we have investigated hematopoietic stem cell (HSC) homeostasis in a mouse model for non-progressive CKD-mineral and bone disorder with experimentally induced chronic renal failure (CRF). In mice subjected to 12 weeks of CRF, bone marrow HSC frequencies were decreased and transplantation of bone marrow cells from CRF donors showed a decrease in long-term HSC repopulation compared to controls. This loss was directly associated with a CRF-induced defect in the HSC niche affecting the cell cycle status of HSC and could not be restored by the PTH-reducing agent cinacalcet. In CRF, frequencies of quiescent (G0) HSC were decreased coinciding with an increase in hematopoietic progenitor cells (HPC) in the S-and G2-phases of cell cycle. Moreover, in CRF mice, HSC-niche supporting macrophages were decreased compared to controls concomitant to impaired B lymphopoiesis. Our data point to a permanent loss of HSC and may provide insight into the root cause of the loss of homeostatic potential in CKD.

Abdominal Aortic Calcifications Influences the Systemic and Renal Hemodynamic Response to Renal Denervation in the DENERHTN (Renal Denervation for Hypertension) Trial.

BACKGROUND: The DENERHTN (Renal Denervation for Hypertension) trial confirmed the efficacy of renal denervation (RDN) in lowering daytime ambulatory systolic blood pressure when added to standardized stepped-care antihypertensive treatment (SSAHT) for resistant hypertension at 6 months. METHODS AND RESULTS: This post hoc exploratory analysis assessed the impact of abdominal aortic calcifications (AAC) on the hemodynamic and renal response to RDN at 6 months. In total, 106 patients with resistant hypertension were randomly assigned to RDN plus SSAHT or to the same SSAHT alone (control group). Total AAC volume was measured, with semiautomatic software and blind to randomization, from the aortic hiatus to the iliac bifurcation using the prerandomization noncontrast abdominal computed tomography scans of 90 patients. Measurements were expressed as tertiles. The baseline-adjusted difference in the change in daytime ambulatory systolic blood pressure from baseline to 6 months between the RDN and control groups was -10.1 mm Hg (P=0.0462) in the lowest tertile and -2.5 mm Hg (P=0.4987) in the 2 highest tertiles of AAC volume. Estimated glomerular filtration rate remained stable at 6 months for the patients in the lowest tertile of AAC volume who underwent RDN (+2.5 mL/min per 1.73 m2) but decreased in the control group (-8.0 mL/min per 1.73 m2, P=0.0148). In the 2 highest tertiles of AAC volume, estimated glomerular filtration rate decreased similarly in the RDN and control groups (P=0.2640). CONCLUSIONS: RDN plus SSAHT resulted in a larger decrease in daytime ambulatory systolic blood pressure than SSAHT alone in patients with a lower AAC burden than in those with a higher AAC burden. This larger decrease in daytime ambulatory systolic blood pressure was not associated with a decrease in estimated glomerular filtration rate. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Twenty-Four-Hour Blood Pressure Monitoring to Predict and Assess Impact of Renal Denervation: The DENERHTN Study (Renal Denervation for Hypertension).

The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure (BP) lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report here the effect of denervation on 24-hour BP and its variability and look for parameters that predicted the BP response. Patients with resistant hypertension were randomly assigned to denervation plus stepped-care treatment or treatment alone (control). Average and standard deviation of 24-hour, daytime, and nighttime BP and the smoothness index were calculated on recordings performed at randomization and 6 months. Responders were defined as a 6-month 24-hour systolic BP reduction ≥20 mm Hg. Analyses were performed on the per-protocol population. The significantly greater BP reduction in the denervation group was associated with a higher smoothness index (P=0.02). Variability of 24-hour, daytime, and nighttime BP did not change significantly from baseline to 6 months in both groups. The number of responders was greater in the denervation (20/44, 44.5%) than in the control group (11/53, 20.8%; P=0.01). In the discriminant analysis, baseline average nighttime systolic BP and standard deviation were significant predictors of the systolic BP response in the denervation group only, allowing adequate responder classification of 70% of the patients. Our results show that denervation lowers ambulatory BP homogeneously over 24 hours in patients with resistant hypertension and suggest that nighttime systolic BP and variability are predictors of the BP response to denervation. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Adherence to Antihypertensive Treatment and the Blood Pressure-Lowering Effects of Renal Denervation in the Renal Denervation for Hypertension (DENERHTN) Trial.

BACKGROUND: The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure-lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report the influence of adherence to antihypertensive treatment on blood pressure control. METHODS: One hundred six patients with hypertension resistant to 4 weeks of treatment with indapamide 1.5 mg/d, ramipril 10 mg/d (or irbesartan 300 mg/d), and amlodipine 10 mg/d were randomly assigned to renal denervation plus standardized stepped-care antihypertensive treatment, or the same antihypertensive treatment alone. For standardized stepped-care antihypertensive treatment, spironolactone 25 mg/d, bisoprolol 10 mg/d, prazosin 5 mg/d, and rilmenidine 1 mg/d were sequentially added at monthly visits if home blood pressure was ≥135/85 mm Hg after randomization. We assessed adherence to antihypertensive treatment at 6 months by drug screening in urine/plasma samples from 85 patients. RESULTS: The numbers of fully adherent (20/40 versus 21/45), partially nonadherent (13/40 versus 20/45), or completely nonadherent patients (7/40 versus 4/45) to antihypertensive treatment were not different in the renal denervation and the control groups, respectively (P=0.3605). The difference in the change in daytime ambulatory systolic blood pressure from baseline to 6 months between the 2 groups was -6.7 mm Hg (P=0.0461) in fully adherent and -7.8 mm Hg (P=0.0996) in nonadherent (partially nonadherent plus completely nonadherent) patients. The between-patient variability of daytime ambulatory systolic blood pressure was greater for nonadherent than for fully adherent patients. CONCLUSIONS: In the DENERHTN trial, the prevalence of nonadherence to antihypertensive drugs at 6 months was high (≈50%) but not different in the renal denervation and control groups. Regardless of adherence to treatment, renal denervation plus standardized stepped-care antihypertensive treatment resulted in a greater decrease in blood pressure than standardized stepped-care antihypertensive treatment alone. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Dose-effect relationship of perindopril 10, 14 and 20mg assessed by urine and plasma AcSDKP levels in mildly sodium-depleted healthy volunteers.

BACKGROUND: We describe a pharmacodynamic study of the dose-effect relationship of perindopril arginine at 10, 14, and 20mg with in vivo angiotensin-converting enzyme (ACE) activity, assessed by urine and plasma AcSDKP levels, as well as the effect on plasma active renin concentrations and blood pressure. METHODS: This randomized, double-blind, four-period, crossover study involved single-dose administration of perindopril arginine (10, 14, and 20mg or placebo) to 32 healthy male normotensive mildly sodium-depleted volunteers. Blood and urine were collected over 48h for AcSDKP, ACE activity, and plasma active renin measurements. RESULTS: There were dose-related increases in urinary AcSDKP excretion and plasma AcSDKP concentration after administration of perindopril, with significant between-period differences (estimate of the median difference in urinary excretion over 48h of AcSDKP, 49.1 [95% CI: 15.3-82.0] nmol for 14 versus 10mg, and 73.2 [95% CI: 44.9-106.3] nmol for 20 versus 14mg). Consequently, a dose-dependent increase in plasma active renin concentration was observed. Even though each dose of perindopril 10 to 20mg was associated with a significant 24-h ambulatory blood pressure reduction versus placebo, no dose-dependency was detected in these normotensive subjects. CONCLUSIONS: Administration of perindopril arginine 10, 14, or 20mg to mildly sodium-depleted healthy volunteers is associated with a dose-dependent inhibition of in vivo ACE activity with significant between-dose differences. This effect was associated with a dose-dependent increase in plasma active renin concentration, indicating a dose-dependent blockade of the renin angiotensin system.

Optimum and stepped care standardised antihypertensive treatment with or without renal denervation for resistant hypertension (DENERHTN): a multicentre, open-label, randomised controlled trial.

BACKGROUND: Conflicting blood pressure-lowering effects of catheter-based renal artery denervation have been reported in patients with resistant hypertension. We compared the ambulatory blood pressure-lowering efficacy and safety of radiofrequency-based renal denervation added to a standardised stepped-care antihypertensive treatment (SSAHT) with the same SSAHT alone in patients with resistant hypertension. METHODS: The Renal Denervation for Hypertension (DENERHTN) trial was a prospective, open-label randomised controlled trial with blinded endpoint evaluation in patients with resistant hypertension, done in 15 French tertiary care centres specialised in hypertension management. Eligible patients aged 18-75 years received indapamide 1·5 mg, ramipril 10 mg (or irbesartan 300 mg), and amlodipine 10 mg daily for 4 weeks to confirm treatment resistance by ambulatory blood pressure monitoring before randomisation. Patients were then randomly assigned (1:1) to receive either renal denervation plus an SSAHT regimen (renal denervation group) or the same SSAHT alone (control group). The randomisation sequence was generated by computer, and stratified by centres. For SSAHT, after randomisation, spironolactone 25 mg per day, bisoprolol 10 mg per day, prazosin 5 mg per day, and rilmenidine 1 mg per day were sequentially added from months two to five in both groups if home blood pressure was more than or equal to 135/85 mm Hg. The primary endpoint was the mean change in daytime systolic blood pressure from baseline to 6 months as assessed by ambulatory blood pressure monitoring. The primary endpoint was analysed blindly. The safety outcomes were the incidence of acute adverse events of the renal denervation procedure and the change in estimated glomerular filtration rate from baseline to 6 months. This trial is registered with ClinicalTrials.gov, number NCT01570777. FINDINGS: Between May 22, 2012, and Oct 14, 2013, 1416 patients were screened for eligibility, 106 of those were randomly assigned to treatment (53 patients in each group, intention-to-treat population) and 101 analysed because of patients with missing endpoints (48 in the renal denervation group, 53 in the control group, modified intention-to-treat population). The mean change in daytime ambulatory systolic blood pressure at 6 months was -15·8 mm Hg (95% CI -19·7 to -11·9) in the renal denervation group and -9·9 mm Hg (-13·6 to -6·2) in the group receiving SSAHT alone, a baseline-adjusted difference of -5·9 mm Hg (-11·3 to -0·5; p=0·0329). The number of antihypertensive drugs and drug-adherence at 6 months were similar between the two groups. Three minor renal denervation-related adverse events were noted (lumbar pain in two patients and mild groin haematoma in one patient). A mild and similar decrease in estimated glomerular filtration rate from baseline to 6 months was observed in both groups. INTERPRETATION: In patients with well defined resistant hypertension, renal denervation plus an SSAHT decreases ambulatory blood pressure more than the same SSAHT alone at 6 months. This additional blood pressure lowering effect may contribute to a reduction in cardiovascular morbidity if maintained in the long term after renal denervation. FUNDING: French Ministry of Health.

Eligibility for renal denervation: anatomical classification and results in essential resistant hypertension.

PURPOSE: To classify the renal artery (RA) anatomy based on specific requirements for endovascular renal artery denervation (RDN) in patients with drug-resistant hypertension (RH). MATERIALS AND METHODS: The RA anatomy of 122 consecutive RH patients was evaluated by computed tomography angiography and classified as two types: A (main RA ≥20 mm in length and ≥4.0 mm in diameter) or B (main RA <20 mm in length or main RA <4.0 mm in diameter). The A type included three subtypes: A1 (without accessory RAs), A2 (with accessory RAs <3.0 mm in diameter), and A3 (with accessory RAs ≥3.0 mm in diameter]. A1 and A2 types were eligible for RDN with the Simplicity Flex catheter. Type B included twi subtypes based on the main RA length and diameter. Patients were accordingly classified into three eligibility categories: complete (CE; both RAs were eligible), partial (PE; one eligible RA), and noneligibility (NE; no eligible RA). RESULTS: Bilateral A1 type was the most prevalent and was observed in 48.4 % of the patients followed by the A1/A2 type (18 %). CE, PE, and NE were observed in 69.7, 22.9, and 7.4 % of patients, respectively. The prevalence of accessory RAs was 41 %. CONCLUSIONS: Of RH patients, 30.3 % were not eligible for bilateral RDN with the current Simplicity Flex catheter. This classification provides the basis for standardized reporting to allow for pooling of results of larger patient cohorts in the future.

Indomethacin, amiloride, or eplerenone for treating hypokalemia in Gitelman syndrome.

Patients with Gitelman syndrome (GS), an inherited salt-losing tubulopathy, are usually treated with potassium-sparing diuretics or nonsteroidal anti-inflammatory drugs and oral potassium and magnesium supplementations. However, evidence supporting these treatment options is limited to case series studies. We designed an open-label, randomized, crossover study with blind end point evaluation to compare the efficacy and safety of 6-week treatments with one time daily 75 mg slow-release indomethacin, 150 mg eplerenone, or 20 mg amiloride added to constant potassium and magnesium supplementation in 30 patients with GS (individual participation: 48 weeks). Baseline plasma potassium concentration was 2.8±0.4 mmol/L and increased by 0.38 mmol/L (95% confidence interval [95% CI], 0.23 to 0.53; P<0.001) with indomethacin, 0.15 mmol/L (95% CI, 0.02 to 0.29; P=0.03) with eplerenone, and 0.19 mmol/L (95% CI, 0.05 to 0.33; P<0.01) with amiloride. Fifteen patients became normokalemic: six with indomethacin, three with eplerenone, and six with amiloride. Indomethacin significantly reduced eGFR and plasma renin concentration. Eplerenone and amiloride each increased plasma aldosterone by 3-fold and renin concentration slightly but did not significantly change eGFR. BP did not significantly change. Eight patients discontinued treatment early because of gastrointestinal intolerance to indomethacin (six patients) and hypotension with eplerenone (two patients). In conclusion, each drug increases plasma potassium concentration in patients with GS. Indomethacin was the most effective but can cause gastrointestinal intolerance and decreased eGFR. Amiloride and eplerenone have similar but lower efficacies and increase sodium depletion. The benefit/risk ratio of each drug should be carefully evaluated for each patient.

Silencing of miRNA-126 in kidney ischemia reperfusion is associated with elevated SDF-1 levels and mobilization of Sca-1+/Lin- progenitor cells.

Integrity of the capillary network in the kidney is essential in the recovery from ischemia/ reperfusion injury (IRI), a phenomenon central to kidney transplantation and acute kidney injury. MicroRNA- 126 (miR-126) is known to be important in maintaining vascular homeostasis by facilitating vascular regeneration and modulating the mobilization of vascular progenitor cells. Stromal cell-derived factor 1 (SDF-1), important in the mobilization of vascular progenitor cells, is a direct target of miR-126 and modulation of miR-126 was previously shown to affect the number of circulating Sca-1(+)/Lin(-) vascular progenitor cells in a mouse model for hind limb ischemia. Here, we assessed the in vivo contribution of miR-126 to progenitor cell mobilization and kidney function following IRI in mice. A three day follow up of blood urea levels following kidney IRI demonstrated that systemic antagomir silencing of miR-126 did not impact the loss or subsequent restoration of kidney function. However, whole kidney lysates displayed elevated gene expression levels of Sdf-1, Vegf-A and eNOS after IRI as a result of systemic silencing of miR-126. Furthermore, FACS-analysis on whole blood three days after surgery revealed a marked up regulation of the number of circulating Sca-1(+)/Lin(-) progenitor cells in the antagomir-126 treated mice, in an ischemia dependent manner. Our data indicate that silencing of miR-126 can enhance renal expression of Sdf-1 after IRI, leading to the mobilization of vascular progenitor cells into the circulation.

Thrombotic thrombocytopenic purpura due to anti-ADAMTS13 antibodies in multiple myeloma.

CONTEXT: Thrombotic thrombocytopenic purpura (TTP) is a particularly serious form of thrombotic microangiopathy (TMA) due to the risk of multiple organ dysfunction. Several etiological factors such as infection, auto-immune disease, certain medications and cancers have been associated with TTP. CLINICAL CASES: A 74-year-old hypertensive woman with a history of thromboembolic disease was hospitalized for acute kidney injury (AKI) associated with pneumonia. Initial investigations were suggestive of Pneumocystis jirovecii infection and myeloma cast nephropathy. Several days later, the patient presented features of TTP. Von Willebrand factor-cleaving protease activity was less than 5% with a high level of IgG antibody directed against ADAMTS13. Treatment consisted of monthly 4-day cycles of dexamethasone and melphalan in combination with plasmapheresis and resulted in a favorable outcome. Three years after ceasing treatment, the patient presented no signs of hemolysis, but required chronic hemodialysis. CONCLUSION: The association of TMA, especially TTP, and multiple myeloma is exceptional. The authors report such a case that induced irreversible renal damage, but with stable clinical and laboratory parameters with a follow-up of 4 years.

New drug therapies interfering with the renin-angiotensin-aldosterone system for resistant hypertension.

There is a persistent need for the development of new antihypertensive drugs, because the control of blood pressure is still not achievable in a significant proportion of hypertensive patients. Since the approval in 2007 of aliskiren, no other new antihypertensive based on new mechanism(s) of action have been approved. In fact, the development of promising novel drugs has been stopped for safety, efficacy or marketing reasons. Despite these difficulties, the pipeline is not dry and different new antihypertensive strategies targeting the renin-angiotensin-aldosterone pathway, are in clinical development stage. The dual angiotensin II receptor-neprilysin inhibitor LCZ696, a single molecule synthetized by cocrystallisation of valsartan and the neprilysin inhibitor prodrug AHU377 is in development for resistant hypertension and for heart failure. Daglutril is a dual neprylisin-endothelin converting enzyme inhibitor which was shown to decrease BP in patients with type 2 diabetic nephropathy. Aldosterone synthase inhibitors and the third and fourth generation non-steroidal dihydropyridine based mineralocorticoid receptors blockers are new ways to target the multiple noxious effects of aldosterone in the kidney, vessels and heart. Centrally acting aminopeptidase A inhibitors block brain angiotensin III formation, one of the main effector peptides of the brain renin angiotensin system. However, a long time will be still necessary to evaluate extensively the efficacy and safety of these new approaches. In the mean time, using appropriate and personalized daily doses of available drugs, decreasing physician inertia, improving treatment adherence, improving access to healthcare and reducing treatment costs remain major objectives to reduce the incidence of resistant hypertension.

Transcriptomic analysis of the effect of ifosfamide on MDCK cells cultivated in microfluidic biochips.

We investigated the behavior of renal cells cultivated in microfluidic biochips when exposed to 50 µM of ifosfamide, an antineoplastic drug treatment. The microarray analysis revealed that ifosfamide had any effect in Petri conditions. The microfluidic biochips induced an early inflammatory response in the MDCK in the untreated cells. This was attributed to cells adapting to the dynamics and micro environment created by the biochips. This led to modulations in the mitochondria dysfunction pathway, the Nrf-2 and oxidative stress pathways and some related cancer genes. When exposed to 50 µM of ifosfamide, we detected a modulation of the pathways related to the cancer and inflammation in the MDCK cultivated in the biochips via modulation of the ATM, p53, MAP Kinase, Nrf-2 and NFKB signaling. In addition, the genes identified and related proteins affected by the ifosfamide treatment in the biochips such as TXNRD1, HSP40 (DNAJB4 and DNAJB9), HSP70 (HSPA9), p21 (CDKN1A), TP53, IKBalpha (NFKBIA) are reported to be the molecular targets in cancer therapy. We also found that the integrin pathway was perturbed with the ifosfamide treatment. Finally, the MYC proto-oncogene appeared to be a potential bridge between the integrin signaling and the anti-inflammatory response.

Analysis of transcriptomic and proteomic profiles demonstrates improved Madin-Darby canine kidney cell function in a renal microfluidic biochip.

We have evaluated the influence of the microfluidic environment on renal cell functionality. For that purpose, we performed a time lapse transcriptomic and proteomic analysis in which we compared gene and protein expressions of Madin-Darby canine kidney cells after 24 h and 96 h of culture in both microfluidic biochips and plates. The transcriptomic and proteomic integration revealed that the ion transporters involved in calcium, phosphate, and sodium homoeostasis and several genes involved in H(+) transporters and pH regulation were up-regulated in microfluidic biochips. Concerning drug metabolism, we found Phase I (CYP P450), Phase II enzymes (GST), various multidrug resistance genes (MRP), and Phase III transporters (SLC) were also up-regulated in the biochips. Furthermore, the study shows that those inductions were correlated with the induction of the Ahr and Nrf-2 dependent pathways, which results in a global cytoprotective response induced by the microenvironment. However, there was no apoptosis situation or cell death in the biochips. Microfluidic biochips may thus provide an important insight into exploring xenobiotic injury and transport modifications in this type of bioartificial microfluidic kidney. Finally, the investigation demonstrated that combining the transcriptomic and proteomic analyses obtained from a cell "on chip" culture would provide a pertinent new tool in the mechanistic interpretation of cellular mechanisms for predicting kidney cell toxicity and renal clearance in vitro.